Genetic Attributes of E. coli Isolates from Chlorinated Drinking Water

PubMed Central

Blyton, Michaela D. J.; Gordon, David M.

2017-01-01

Escherichia coli, is intimately associated with both human health and water sanitation. E. coli isolates from water can either be (i) host associated commensals, indicating recent faecal contamination; (ii) diarrheal pathogens or (iii) extra-intestinal pathogens that pose a direct health risk; or (iv) free-living. In this study we genetically characterised 28 E. coli isolates obtained from treated drinking water in south eastern Australia to ascertain their likely source. We used full genome sequencing to assign the isolates to their phylogenetic group and multi-locus sequence type. The isolates were also screened in silico for several virulence genes and genes involved in acquired antibiotic resistance. The genetic characteristics of the isolates indicated that four isolates were likely human pathogens. However, these isolates were not detected in sufficient numbers to present a health risk to the public. An additional isolate was a human associated strain. Nine isolates were water associated free-living strains that were unlikely to pose a health risk. Only 14% of the isolates belonged to the host associated phylogenetic group (B2) and only a single isolate had any antibiotic resistance genes. This suggests that the primary source of the drinking water E. coli isolates may not have been recent human faecal contamination. PMID:28107364

Genetic Attributes of E. coli Isolates from Chlorinated Drinking Water.

PubMed

Blyton, Michaela D J; Gordon, David M

2017-01-01

Escherichia coli, is intimately associated with both human health and water sanitation. E. coli isolates from water can either be (i) host associated commensals, indicating recent faecal contamination; (ii) diarrheal pathogens or (iii) extra-intestinal pathogens that pose a direct health risk; or (iv) free-living. In this study we genetically characterised 28 E. coli isolates obtained from treated drinking water in south eastern Australia to ascertain their likely source. We used full genome sequencing to assign the isolates to their phylogenetic group and multi-locus sequence type. The isolates were also screened in silico for several virulence genes and genes involved in acquired antibiotic resistance. The genetic characteristics of the isolates indicated that four isolates were likely human pathogens. However, these isolates were not detected in sufficient numbers to present a health risk to the public. An additional isolate was a human associated strain. Nine isolates were water associated free-living strains that were unlikely to pose a health risk. Only 14% of the isolates belonged to the host associated phylogenetic group (B2) and only a single isolate had any antibiotic resistance genes. This suggests that the primary source of the drinking water E. coli isolates may not have been recent human faecal contamination.

Genomic Comparative Study of Bovine Mastitis Escherichia coli.

PubMed

Kempf, Florent; Slugocki, Cindy; Blum, Shlomo E; Leitner, Gabriel; Germon, Pierre

2016-01-01

Escherichia coli, one of the main causative agents of bovine mastitis, is responsible for significant losses on dairy farms. In order to better understand the pathogenicity of E. coli mastitis, an accurate characterization of E. coli strains isolated from mastitis cases is required. By using phylogenetic analyses and whole genome comparison of 5 currently available mastitis E. coli genome sequences, we searched for genotypic traits specific for mastitis isolates. Our data confirm that there is a bias in the distribution of mastitis isolates in the different phylogenetic groups of the E. coli species, with the majority of strains belonging to phylogenetic groups A and B1. An interesting feature is that clustering of strains based on their accessory genome is very similar to that obtained using the core genome. This finding illustrates the fact that phenotypic properties of strains from different phylogroups are likely to be different. As a consequence, it is possible that different strategies could be used by mastitis isolates of different phylogroups to trigger mastitis. Our results indicate that mastitis E. coli isolates analyzed in this study carry very few of the virulence genes described in other pathogenic E. coli strains. A more detailed analysis of the presence/absence of genes involved in LPS synthesis, iron acquisition and type 6 secretion systems did not uncover specific properties of mastitis isolates. Altogether, these results indicate that mastitis E. coli isolates are rather characterized by a lack of bona fide currently described virulence genes.

Genomic Comparative Study of Bovine Mastitis Escherichia coli

PubMed Central

Kempf, Florent; Slugocki, Cindy; Blum, Shlomo E.; Leitner, Gabriel; Germon, Pierre

2016-01-01

Escherichia coli, one of the main causative agents of bovine mastitis, is responsible for significant losses on dairy farms. In order to better understand the pathogenicity of E. coli mastitis, an accurate characterization of E. coli strains isolated from mastitis cases is required. By using phylogenetic analyses and whole genome comparison of 5 currently available mastitis E. coli genome sequences, we searched for genotypic traits specific for mastitis isolates. Our data confirm that there is a bias in the distribution of mastitis isolates in the different phylogenetic groups of the E. coli species, with the majority of strains belonging to phylogenetic groups A and B1. An interesting feature is that clustering of strains based on their accessory genome is very similar to that obtained using the core genome. This finding illustrates the fact that phenotypic properties of strains from different phylogroups are likely to be different. As a consequence, it is possible that different strategies could be used by mastitis isolates of different phylogroups to trigger mastitis. Our results indicate that mastitis E. coli isolates analyzed in this study carry very few of the virulence genes described in other pathogenic E. coli strains. A more detailed analysis of the presence/absence of genes involved in LPS synthesis, iron acquisition and type 6 secretion systems did not uncover specific properties of mastitis isolates. Altogether, these results indicate that mastitis E. coli isolates are rather characterized by a lack of bona fide currently described virulence genes. PMID:26809117

Population structure of Cladophora-borne Escherichia coli in nearshore water of Lake Michigan.

PubMed

Byappanahalli, Muruleedhara N; Whitman, Richard L; Shively, Dawn A; Ferguson, John; Ishii, Satoshi; Sadowsky, Michael J

2007-08-01

We previously reported that the macrophytic green alga Cladophora harbors high densities (up to 10(6) colony-forming units/g dry weight) of the fecal indicator bacteria, Escherichia coli and enterococci, in shoreline waters of Lake Michigan. However, the population structure and genetic relatedness of Cladophora-borne indicator bacteria remain poorly understood. In this study, 835 E. coli isolates were collected from Cladophora tufts (mats) growing on rocks from a breakwater located within the Indiana Dunes National Lakeshore in northwest Indiana. The horizontal fluorophore enhanced rep-PCR (HFERP) DNA fingerprinting technique was used to determine the genetic relatedness of the isolates to each other and to those in a library of E. coli DNA fingerprints. While the E. coli isolates from Cladophora showed a high degree of genetic relatedness (92% similarity), in most cases, however, the isolates were genetically distinct. The Shannon diversity index for the population was very high (5.39). Both spatial and temporal influences contributed to the genetic diversity. There was a strong association of isolate genotypes by location (79% and 80% for lake- and ditch-side samplings, respectively), and isolates collected from 2002 were distinctly different from those obtained in 2003. Cladophora-borne E. coli isolates represented a unique group, which was distinct from other E. coli isolates in the DNA fingerprint library tested. Taken together, these results indicate that E. coli strains associated with Cladophora may be a recurring source of indicator bacteria to the nearshore beach.

Assessment of pit latrines in a peri-urban community in KwaZulu-Natal (South Africa) as a source of antibiotic resistant E. coli strains.

PubMed

Beukes, Lorika S; King, Tracy L B; Schmidt, Stefan

2017-11-01

Due to the frequent use of antibiotics and recurring illnesses related to multidrug-resistant (MDR) bacteria in South Africa, we determined if MDR Escherichia coli were present in pit latrine fecal sludge samples obtained from a peri-urban community in KwaZulu-Natal, South Africa. The abundance of E. coli in pit latrine samples was established using a most probable number (MPN) method with species confirmation done using biochemical tests and polymerase chain reaction (PCR). Forty-four randomly selected E. coli pit latrine isolates were further characterized, using the European committee on antimicrobial susceptibility testing (EUCAST) disk diffusion method to establish antibiotic resistance profiles for these E. coli isolates. The resulting MPN values for E. coli ranged from one to 6.2 log 10 MPN per gram of fresh pit latrine fecal sludge. While only 3 out of 44 E. coli pit latrine isolates showed no resistance to any of the 12 tested antibiotics, most isolates were resistant to two or more antibiotics. The majority of isolates showed resistance to at least one of the two tested aminoglycosides, one isolate showed resistance to the carbapenem ertapenem, and although resistance was not detected for tigecycline four pit latrine E. coli isolates showed intermediate resistance to this antibiotic. However, about 14% of the E. coli pit latrine isolates were categorized as MDR, all of which showed resistance to four or more antibiotics. The presence of MDR E. coli strains in pit latrine samples demonstrates that these facilities are potential sources for MDR bacteria. Copyright © 2017 Elsevier GmbH. All rights reserved.

Abundance and characteristics of the recreational water quality indicator bacteria Escherichia coli and enterococci in gull faeces

USGS Publications Warehouse

Fogarty, L.R.; Haack, S.K.; Wolcott, M.J.; Whitman, R.L.

2003-01-01

Aims: To evaluate the numbers and selected phenotypic and genotypic characteristics of the faecal indicator bacteria Escherichia coli and enterococci in gull faeces at representative Great Lakes swimming beaches in the United States. Methods and Results: E. coli and enterococci were enumerated in gull faeces by membrane filtration. E. coli genotypes (rep-PCR genomic profiles) and E. coli (Vitek?? GNI+) and enterococci (API?? rapid ID 32 Strep and resistance to streptomycin, gentamicin, vancomycin, tetracycline and ampicillin) phenotypes were determined for isolates obtained from gull faeces both early and late in the swimming season. Identical E. coli genotypes were obtained only from single gull faecal samples but most faecal samples yielded more than one genotype (median of eight genotypes for samples with 10 isolates). E. coli isolates from the same site that clustered at ???85% similarity were from the same sampling date and shared phenotypic characteristics, and at this similarity level there was population overlap between the two geographically isolated beach sites. Enterococcus API?? profiles varied with sampling date. Gull enterococci displayed wide variation in antibiotic resistance patterns, and high-level resistance to some antibiotics. Conclusions: Gull faeces could be a major contributor of E. coli (105-109 CFU g-1) and enterococci (104-108 CFU g-1) to Great Lakes recreational waters. E. coli and enterococci in gull faeces are highly variable with respect to their genotypic and phenotypic characteristics and may exhibit temporal or geographic trends in these features. Significance and Impact of the Study: The high degree of variation in genotypic or phenotypic characteristics of E. coli or enterococci populations within gull hosts will require extensive sampling for adequate characterization, and will influence methods that use these characteristics to determine faecal contamination sources for recreational waters.

Escherichia coli-producing extended-spectrum beta-lactamase CTX-M-15 in a captive South American tapir (Tapirus terrestris).

PubMed

Klimes, Jiri; Machalkova, Marketa; Dolejska, Monika; Cizek, Alois; Janoszowska, Dagmar; Alexa, Pavel; Albrechtova, Katerina; Vojtech, Jiri; Literak, Ivan

2013-03-01

Only a few reports exist on the occurrence of resistant bacteria in zoo animals. Therefore, an isolation of multiresistant Escherichia coli from the lungs of a captive South American tapir (Tapirus terrestris) lead to its characterization and further investigation of samples from animals inhabiting the same paddock and from the shared environment. The tapir suffered from an intermandibular abscess and pneumonia and was euthanatized after unsuccessful therapy, including administration of antibiotics. The authors performed selective isolation of extended-spectrum beta-lactamase (ESBL)-positive E. coli strains and identification of resistance genes using polymerase chain reaction. Seven multiresistant, ESBL-producing E. coli isolates were obtained, all belonging to the B2 phylogenetic group and showing identical profile on pulsed-field gel electrophoresis. These isolates carried several resistance genes, including the gene bla(CTX-M-15). This case demonstrates the transmission of related epidemiologically important E. coli isolates whose potential transmission to other animals and zoo staff can be assumed.

Characterization of Escherichia coli and other Enterobacteriaceae in producer-distributor bulk milk.

PubMed

Ntuli, V; Njage, P M K; Buys, E M

2016-12-01

The current study was undertaken to characterize Escherichia coli and other Enterobacteriaceae in raw and pasteurized producer-distributor bulk milk (PDBM). A total of 258 samples were collected from purchase points in 8 provinces in South Africa. The samples were tested for antibiotic residues, phosphatase, total aerobic bacteria, coliforms, and E. coli counts. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used for identification of isolates. Escherichia coli isolates were characterized for virulence factors, antimicrobial resistance, serotypes, and presumptive E. coli O157:H7. Antibiotic residues and alkaline phosphatase were detected in 2% of both raw and pasteurized PDBM (n=258) and 21% pasteurized PDBM (n=104) samples, respectively. A total of 729 isolates belonging to 21 genera and 59 species were identified. Escherichia coli, Enterobacter cloacae, Klebsiella oxytoca, and Raoultella ornithinolytica were the most abundant species. Spoilage Enterobacteriaceae species exceeded 50% of the total isolates. Escherichia coli was detected and isolated from 36% of the milk samples. Thirty-one E. coli isolates harbored virulence genes stx1/stx2 and 38% (n=121) were presumptive O157:H7. The prevalence of samples with presumptive shigatoxin producing E. coli was 10%. Antimicrobial-resistant E. coli isolates were detected in 70% of the milk samples with 36% of stx1/stx2 positive E. coli showing multi-drug resistance. Information obtained from the study will be used for modeling the public health risk posed by milkborne pathogens in PDBM, which in many cases is consumed by poor and vulnerable members of the population. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antimicrobial resistance trends among Escherichia coli isolates obtained from dairy cattle in the northeastern United States, 2004-2011.

PubMed

Cummings, Kevin J; Aprea, Victor A; Altier, Craig

2014-01-01

Monitoring antimicrobial resistance trends among bacteria isolated from food animals and people is necessary to inform risk analyses and guide public policy regarding antimicrobial use. Our objectives were to describe the antimicrobial resistance status of Escherichia coli isolates from dairy cattle in the northeastern United States and to identify trends in resistance to selected antimicrobial agents over time. We collected data retrospectively for all bovine E. coli isolates that were obtained from samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. We investigated temporal trends in the prevalence of resistant E. coli for each antimicrobial agent using the Cochran-Armitage trend test. Antimicrobial susceptibility testing was performed on 3373 bovine E. coli isolates from clinical samples submitted during the study period. Overall resistance to each antimicrobial agent ranged from 2.7% (enrofloxacin) to 91.3% (oxytetracycline). There was evidence of a significantly decreasing trend in prevalence of resistance to several agents: chlortetracycline, florfenicol, neomycin, oxytetracycline, spectinomycin, and trimethoprim/sulfamethoxazole. However, a significantly increasing trend in prevalence of resistance to enrofloxacin was also evident. These results do not support the idea that current antimicrobial use practices on dairy operations are driving a general increase in the emergence and dissemination of drug-resistant E. coli in the region served by the laboratory. However, resistance to some drugs remained consistently high during the study period, and increasing resistance to enrofloxacin is a key area of concern.

SURVIVAL OF ESCHERICHIA COLI 0157:H7 IN DAIRY CATTLE FEED WATER

EPA Science Inventory

Cattle feed waters from two dairy farms were used in a study to determine the survival characteristics of the bacterial pathogen Escherichia coli )157:H7 and wild-type E. coli. The E. coli 0157:H7 inoculum consisted of a consortium of isolates obtained from dairy cattle. Fresh ma...

Genotypic characterization of ESBL-producing E. coli from imported meat in South Korea.

PubMed

Kim, Young-Jo; Moon, Jin-San; Oh, Deog-Hwan; Chon, Jung-Whan; Song, Bo-Ra; Lim, Jong-Su; Heo, Eun-Jeong; Park, Hyun-Jung; Wee, Sung-Hwan; Sung, Kidon

2018-05-01

Twenty extended-spectrum β-lactamase (ESBL)-producing E. coli strains were isolated from imported meat in South Korea. ESBL strains of E. coli were detected in chicken (14/20) more often than in pork (6/20) and beef (0/20); the highest number (12/20) was detected in Brazilian meats. The bla CTX-M genes were predominant in meats from many countries. E. coli from pork imported from France produced the bla CTX-M-58 enzyme, which has never been documented previously in ESBL-producing bacteria from clinical or environmental sources. Additionally, the coexistence of the bla CTX-M-2 and bla OXA-1 enzymes in EC12-5 isolate was found for the first time in an ESBL E. coli isolate. A rare bla CTX-M type, bla CTX-M-25 , was found in 40% of ESBL E. coli isolates. Phenotypic susceptibility testing showed that E. coli isolates were resistant to up to eleven antibiotics, including ciprofloxacin. For the first time, a new combination in an integron gene cassette, aacA4-cmlA6-qacEΔ1, was found in an E. coli isolate from poultry imported from Brazil. Three E. coli ST117 isolates, from an avian pathogenic lineage producing CTX-M-94, harbored fimH, fyuA, iutA, papC, rfc, and traT virulence genes and were not susceptible to quinolones. For the first time, rfc and papG virulence factors were detected in ESBL E. coli strains isolated from meat products. Even though E. coli CC21 and CC22 were obtained from meats from the USA and Brazil, respectively, they had a similarity coefficient higher than 99% in rep-PCR and the same MLST type (ST117), phenotypic antibiotic resistance pattern, integron gene (qacEΔ1), and plasmid DNA profile. This study indicates that imported meat products may be a source of ESBL-producing E. coli strains in South Korea. Published by Elsevier Ltd.

Adherence and virulence genes of Escherichia coli from children diarrhoea in the Brazilian Amazon.

PubMed

Benevides-Matos, Najla; Pieri, Fabio A; Penatti, Marilene; Orlandi, Patrícia P

2015-03-01

The bacterial pathogen most commonly associated with endemic forms of childhood diarrhoea is Escherichia coli . Studies of epidemiological characteristics of HEp-2 cell-adherent E. coli in diarrhoeal disease are required, particularly in developing countries. The aim of this study was evaluate the presence and significance of adherent Escherichia coli from diarrhoeal disease in children. The prevalence of LA, AA, and DA adherence patterns were determined in HEp-2 cells, the presence of virulence genes and the presence of the O serogroups in samples obtained from 470 children with acute diarrhoea and 407 controls in Porto Velho, Rondônia, Brazil. E. coli isolates were identified by PCR specific for groups of adherent E. coli . Out of 1,156 isolates obtained, 128 (11.0%) were positive for eae genes corresponding to EPEC, however only 38 (29.6%) of these amplified bfpA gene . EAEC were isolated from 164 (14.1%) samples; of those 41(25%), 32 (19%) and 16 (9.7%) amplified eagg , aggA or aafA genes, respectively and aggA was significantly associated with diarrhoea ( P = 0.00006). DAEC identified by their adhesion pattern and there were few isolates. In conclusion, EAEC was the main cause of diarrhoea in children, especially when the aggA gene was present, followed by EPEC and with a negligible presence of DAEC.

[Hospital and community-acquired β-lactamases-producing Escherichia coli and Klebsiella pneumoniae at hospitals in Hermosillo, Sonora].

PubMed

Navarro-Navarro, Moisés; Robles-Zepeda, Ramón Enrique; Garibay-Escobar, Adriana; Ruiz-Bustos, Eduardo

2011-01-01

To determine the prevalence of extended-spectrum β-lactamases (ESBL)-producing Esherichia coli and Klebsiella pneumoniae in hospitals of Hermosillo, Sonora, Mexico. To detect ESBL-production, 1 412 bacterial isolates obtained over a one year period (2008-2009) were analyzed using the double-disk synergy test, with and without clavulanic acid. Hospitalaryacquired ESBL-producing E.coli and K.pneumoniae (31.8% and 35.3%) were isolated with higher prevalence that community-acquired isolates (14.4% and 0.0%) (p<0.005). Our study shows the presence of ESBL-producing bacteria in the three hospitals.

Impact of a Stewardship-Initiated Restriction on Empirical Use of Ciprofloxacin on Nonsusceptibility of Escherichia coli Urinary Isolates to Ciprofloxacin.

PubMed

O'Brien, Kristen A; Zhang, Jingwen; Mauldin, Patrick D; Gomez, Juanmanuel; Hurst, John M; Sean Boger, M; Bosso, John A

2015-05-01

To evaluate the impact of a stewardship-initiated restriction on empirical use of ciprofloxacin on the nonsusceptibility of Escherichia coli urinary isolates to ciprofloxacin over time while controlling for the use of other key antibiotics with gram-negative activity. Retrospective single-center study. Large tertiary and quaternary care academic medical center. Of 3714 E. coli urinary isolates. The susceptibilities of the E. coli urinary isolates to ciprofloxacin, ceftriaxone, cefepime, piperacillin-tazobactam, meropenem, trimethoprim-sulfamethoxazole, and nitrofurantoin obtained over a 7-year period (January 1, 2006-December 31, 2012) from adult inpatients were evaluated for potential relationships with antibiotic use over time by using multiple variable regression analysis. After introduction of the restriction on empirical use of ciprofloxacin in the first quarter of 2011, ciprofloxacin use declined from 141.1-39.8 defined daily doses/1000 patient-days, and the percentage of E. coli isolates that were not susceptible to ciprofloxacin decreased from 41.5-32.8%. With all antibiotics evaluated included in the model, no apparent relationships were found between the percentage of E. coli isolates nonsusceptible to ciprofloxacin and antibiotic use. However, when nonsignificant variables were eliminated (p>0.20), ciprofloxacin use was found to be positively associated with the percentage of E. coli isolates nonsusceptible to ciprofloxacin (p=0.037), whereas ceftriaxone use was negatively associated (p=0.045). The restriction and subsequent reduction of ciprofloxacin use was found to have a positive effect on the susceptibility of E. coli urinary isolates to ciprofloxacin. © 2015 Pharmacotherapy Publications, Inc.

Population structure of Cladophora-borne Escherichia coli in nearshore water of Lake Michigan

USGS Publications Warehouse

Byappanahalli, M.N.; Whitman, R.L.; Shively, D.A.; Ferguson, J.; Ishii, S.; Sadowsky, M.J.

2007-01-01

We previously reported that the macrophytic green alga Cladophora harbors high densities (up to 106 colony-forming units/g dry weight) of the fecal indicator bacteria,Escherichia coli and enterococci, in shoreline waters of Lake Michigan. However, the population structure and genetic relatedness of Cladophora-borne indicator bacteria remain poorly understood. In this study, 835 E. coli isolates were collected fromCladophora tufts (mats) growing on rocks from a breakwater located within the Indiana Dunes National Lakeshore in northwest Indiana. The horizontal fluorophore enhanced rep-PCR (HFERP) DNA fingerprinting technique was used to determine the genetic relatedness of the isolates to each other and to those in a library of E. coli DNA fingerprints. While the E. coli isolates from Cladophora showed a high degree of genetic relatedness (⩾92% similarity), in most cases, however, the isolates were genetically distinct. The Shannon diversity index for the population was very high (5.39). Both spatial and temporal influences contributed to the genetic diversity. There was a strong association of isolate genotypes by location (79% and 80% for lake- and ditch-side samplings, respectively), and isolates collected from 2002 were distinctly different from those obtained in 2003. Cladophora-borne E. coli isolates represented a unique group, which was distinct from other E. coli isolates in the DNA fingerprint library tested. Taken together, these results indicate that E. coli strains associated with Cladophora may be a recurring source of indicator bacteria to the nearshore beach.

Shiga toxin-producing Escherichia coli distribution and characterization in a pasture-based cow-calf production system.

PubMed

Baltasar, Patrícia; Milton, Stewart; Swecker, William; Elvinger, François; Ponder, Monica

2014-05-01

Shiga toxin-producing Escherichia coli (STEC) strains are commonly found in cattle gastrointestinal tracts. In this study, prevalence and distribution of E. coli virulence genes (stx1, stx2, hlyA, and eaeA) were assessed in a cow-calf pasture-based production system. Angus cows (n = 90) and their calves (n = 90) were kept in three on-farm locations, and fecal samples were collected at three consecutive times (July, August, and September 2011). After enrichment of samples, stx1, stx2, eaeA, and hlyA were amplified and detected with a multiplex PCR (mPCR) assay. Fecal samples positive for stx genes were obtained from 93.3% (84 of 90) of dams and 95.6% (86 of 90) of calves at one or more sampling times. Age class (dam or calf), spatial distribution of cattle (farm locations B, H, K), and sampling time influenced prevalence and distribution of virulence genes in the herd. From 293 stx-positive fecal samples, 744 E. coli colonies were isolated. Virulence patterns of isolates were determined through mPCR assay: stx1 was present in 41.9% (312 of 744) of the isolates, stx2 in 6.5% (48 of 744), eaeA in 4.2% (31 of 744), and hlyA in 2.4% (18 of 744). Prevalence of non-O157 STEC was high among the isolates: 33.8% (112 of 331) were STEC O121, 3.6% (12 of 331) were STEC O103, and 1.8% (6 of 331) were STEC O113. One isolate (0.3%) was identified as STEC O157. Repetitive element sequence-based PCR (rep-PCR) fingerprinting was used to study genetic diversity of stx-positive E. coli isolates. Overall, rep-PCR fingerprints were highly similar, supporting the hypothesis that strains are transmitted between animals but not necessarily from a dam to its calf. Highly similar STEC isolates were obtained at each sampling time, but isolates obtained from dams were more diverse than those from calves, suggesting that strain differences in transference may exist. Understanding the transfer of E. coli from environmental and animal sources to calves may aid in developing intervention strategies to reduce E. coli colonization of young cattle.

Veterinary Hospital Dissemination of CTX-M-15 Extended-Spectrum Beta-Lactamase-Producing Escherichia coli ST410 in the United Kingdom.

PubMed

Timofte, Dorina; Maciuca, Iuliana Elena; Williams, Nicola J; Wattret, Andrew; Schmidt, Vanessa

2016-10-01

We characterized extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR) in 32 Escherichia coli extended spectrum cephalosporin (ESC)-resistant clinical isolates from UK companion animals from several clinics. In addition, to investigate the possible dissemination of ESBL clinical isolates within a veterinary hospital, two ESBL-producing E. coli isolates from a dog with septic peritonitis and a cluster of environmental ESC-resistant E. coli isolates obtained from the same clinic and during the same time period, as these two particular ESBL-positive clinical isolates, were also included in the study. Molecular characterization identified bla CTX-M to be the most prevalent gene in ESC-resistant isolates, where 66% and 27% of clinical isolates carried bla CTX-M-15 and bla CTX-M-14, respectively. The only PMQR gene detected was aac(6')-Ib-cr, being found in 34% of the ESC E. coli isolates and was associated with the carriage of bla CTX-M-15 . The clinical and environmental isolates investigated for hospital dissemination had a common ESBL/AmpC phenotype, carried bla CTX-M-15 , and co-harbored bla OXA-1, bla TEM-1, bla CMY-2, and aac(6')-Ib-cr. Multilocus sequence typing identified them all as ST410, while pulse-field gel electrophoresis demonstrated 100% homology of clinical and environmental isolates, suggesting hospital environmental dissemination of CTX-M-15-producing E. coli ST410.

Multi-scale temporal and spatial variation in genotypic composition of Cladophora-borne Escherichia coli populations in Lake Michigan.

PubMed

Badgley, Brian D; Ferguson, John; Vanden Heuvel, Amy; Kleinheinz, Gregory T; McDermott, Colleen M; Sandrin, Todd R; Kinzelman, Julie; Junion, Emily A; Byappanahalli, Muruleedhara N; Whitman, Richard L; Sadowsky, Michael J

2011-01-01

High concentrations of Escherichia coli in mats of Cladophora in the Great Lakes have raised concern over the continued use of this bacterium as an indicator of microbial water quality. Determining the impacts of these environmentally abundant E. coli, however, necessitates a better understanding of their ecology. In this study, the population structure of 4285 Cladophora-borne E. coli isolates, obtained over multiple three day periods from Lake Michigan Cladophora mats in 2007-2009, was examined by using DNA fingerprint analyses. In contrast to previous studies that have been done using isolates from attached Cladophora obtained over large time scales and distances, the extensive sampling done here on free-floating mats over successive days at multiple sites provided a large dataset that allowed for a detailed examination of changes in population structure over a wide range of spatial and temporal scales. While Cladophora-borne E. coli populations were highly diverse and consisted of many unique isolates, multiple clonal groups were also present and accounted for approximately 33% of all isolates examined. Patterns in population structure were also evident. At the broadest scales, E. coli populations showed some temporal clustering when examined by year, but did not show good spatial distinction among sites. E. coli population structure also showed significant patterns at much finer temporal scales. Populations were distinct on an individual mat basis at a given site, and on individual days within a single mat. Results of these studies indicate that Cladophora-borne E. coli populations consist of a mixture of stable, and possibly naturalized, strains that persist during the life of the mat, and more unique, transient strains that can change over rapid time scales. It is clear that further study of microbial processes at fine spatial and temporal scales is needed, and that caution must be taken when interpolating short term microbial dynamics from results obtained from weekly or monthly samples. Copyright © 2010 Elsevier Ltd. All rights reserved.

Multi-scale temporal and spatial variation in genotypic composition of Cladophora-borne Escherichia coli populations in Lake Michigan

USGS Publications Warehouse

Badgley, B.D.; Ferguson, J.; Heuvel, A.V.; Kleinheinz, G.T.; McDermott, C.M.; Sandrin, T.R.; Kinzelman, J.; Junion, E.A.; Byappanahalli, M.N.; Whitman, R.L.; Sadowsky, M.J.

2011-01-01

High concentrations of Escherichia coli in mats of Cladophora in the Great Lakes have raised concern over the continued use of this bacterium as an indicator of microbial water quality. Determining the impacts of these environmentally abundant E. coli, however, necessitates a better understanding of their ecology. In this study, the population structure of 4285 Cladophora-borne E. coli isolates, obtained over multiple three day periods from Lake Michigan Cladophora mats in 2007-2009, was examined by using DNA fingerprint analyses. In contrast to previous studies that have been done using isolates from attached Cladophora obtained over large time scales and distances, the extensive sampling done here on free-floating mats over successive days at multiple sites provided a large dataset that allowed for a detailed examination of changes in population structure over a wide range of spatial and temporal scales. While Cladophora-borne E. coli populations were highly diverse and consisted of many unique isolates, multiple clonal groups were also present and accounted for approximately 33% of all isolates examined. Patterns in population structure were also evident. At the broadest scales, E. coli populations showed some temporal clustering when examined by year, but did not show good spatial distinction among sites. E. coli population structure also showed significant patterns at much finer temporal scales. Populations were distinct on an individual mat basis at a given site, and on individual days within a single mat. Results of these studies indicate that Cladophora-borne E. coli populations consist of a mixture of stable, and possibly naturalized, strains that persist during the life of the mat, and more unique, transient strains that can change over rapid time scales. It is clear that further study of microbial processes at fine spatial and temporal scales is needed, and that caution must be taken when interpolating short term microbial dynamics from results obtained from weekly or monthly samples.

Impact of enumeration method on diversity of Escherichia coli genotypes isolated from surface water.

PubMed

Martin, E C; Gentry, T J

2016-11-01

There are numerous regulatory-approved Escherichia coli enumeration methods, but it is not known whether differences in media composition and incubation conditions impact the diversity of E. coli populations detected by these methods. A study was conducted to determine if three standard water quality assessments, Colilert ® , USEPA Method 1603, (modified mTEC) and USEPA Method 1604 (MI), detect different populations of E. coli. Samples were collected from six watersheds and analysed using the three enumeration approaches followed by E. coli isolation and genotyping. Results indicated that the three methods generally produced similar enumeration data across the sites, although there were some differences on a site-by-site basis. The Colilert ® method consistently generated the least diverse collection of E. coli genotypes as compared to modified mTEC and MI, with those two methods being roughly equal to each other. Although the three media assessed in this study were designed to enumerate E. coli, the differences in the media composition, incubation temperature, and growth platform appear to have a strong selective influence on the populations of E. coli isolated. This study suggests that standardized methods of enumeration and isolation may be warranted if researchers intend to obtain individual E. coli isolates for further characterization. This study characterized the impact of three USEPA-approved Escherichia coli enumeration methods on observed E. coli population diversity in surface water samples. Results indicated that these methods produced similar E. coli enumeration data but were more variable in the diversity of E. coli genotypes observed. Although the three methods enumerate the same species, differences in media composition, growth platform, and incubation temperature likely contribute to the selection of different cultivable populations of E. coli, and thus caution should be used when implementing these methods interchangeably for downstream applications which require cultivated isolates. © 2016 The Society for Applied Microbiology.

CTX-M-15-Producing E. coli Isolates from Food Products in Germany Are Mainly Associated with an IncF-Type Plasmid and Belong to Two Predominant Clonal E. coli Lineages

PubMed Central

Irrgang, Alexandra; Falgenhauer, Linda; Fischer, Jennie; Ghosh, Hiren; Guiral, Elisabet; Guerra, Beatriz; Schmoger, Silvia; Imirzalioglu, Can; Chakraborty, Trinad; Hammerl, Jens A.; Käsbohrer, Annemarie

2017-01-01

Extended-spectrum beta-lactamases (ESBL) mediating resistance to 3rd generation cephalosporins are a major public health issue. As food may be a vehicle in the spread of ESLB-producing bacteria, a study on the occurrence of cephalosporin-resistantu Escherichia coli in food was initiated. A total of 404 ESBL-producing isolates were obtained from animal-derived food samples (e.g., poultry products, pork, beef and raw milk) between 2011 and 2013. As CTX-M-15 is the most abundant enzyme in ESBL-producing E. coli causing human infections, this study focusses on E. coli isolates from food samples harboring the blaCTX-M-15 gene. The blaCTX-M-15 gene was detected in 5.2% (n = 21) of all isolates. Molecular analyses revealed a phylogenetic group A ST167 clone that was repeatedly isolated from raw milk and beef samples over a period of 6 months. The analyses indicate that spread of CTX-M-15-producing E. coli in German food samples were associated with a multireplicon IncF (FIA FIB FII) plasmid and additional antimicrobial resistance genes such as aac(6)-Ib-cr, blaOXA−1, catB3, different tet-variants as well as a class 1 integron with an aadA5/dfrA17 gene cassette. In addition, four phylogenetic group A ST410 isolates were detected. Three of them carried a chromosomal copy of the blaCTX-M-15 gene and a single isolate with the gene on a 90 kb IncF plasmid. The blaCTX-M-15 gene was always associated with the ISEcp1 element. In conclusion, CTX-M-15-producing E. coli were detected in German food samples. Among isolates of different matrices, two prominent clonal lineages, namely A-ST167 and A-ST410, were identified. These lineages may be important for the foodborne dissemination of CTX-M-15-producing E. coli in Germany. Interestingly, these clonal lineages were reported to be widely distributed and especially prevalent in isolates from humans and livestock. Transmission of CTX-M-15-harboring isolates from food-producing animals to food appears probable, as isolates obtained from livestock and food samples within the same time period exhibit comparable characteristics as compared to isolates detected from human. However, the routes and direction of transmission need further investigation. PMID:29209306

Studies on occurrence, characterisation and decontamination of emerging pathogenic Escherichia coli (STEC, ETEC and EIEC) in table eggs.

PubMed

Vinayananda, C O; Fairoze, Nadeem; Madhavaprasad, C B; Byregowda, S M; Nagaraj, C S; Bagalkot, Prashanth; Karabasanavar, Nagappa

2017-12-01

1. Escherichia coli is one of the most common facultative anaerobic species present in the gastrointestinal tract of animals and human beings. Usually they occur as commensals, but some serotypes can cause significant illnesses in humans as well as mammals and birds. 2. The occurrence of E. coli in different categories of table eggs collected from markets was evaluated. Isolates were analysed for the presence of virulence genes, antibiotic susceptibility pattern and efficacy of peracetic acid and chlorine for the purpose of decontaminating table eggs. 3. Significant differences were observed in the occurrence of E. coli between different groups viz. processed (cleaned, washed, sanitised and packed eggs), unprocessed (un-cleaned, un-sanitised and loose eggs) and free range (eggs obtained from backyard poultry) table eggs. Overall, E. coli occurred in table eggs at 28.6% with 22.9, 29.2 and 50.0% occurrence in processed, unprocessed and free-range table eggs, respectively. 4. A total of 24 isolates of E. coli were obtained and screened for virulence genes viz. STH, SLT1/2 and INVE genes. Of the 24 isolates recovered, 10 typeable isolates belonged to O141, O119, O9, O120 and O101 serotypes, while the remaining 14 were untypeable. Antibiograms of the isolates showed multiple antimicrobial resistance (MAR) index in the range of 0.13-0.40. 5. Peracetic acid (PAA) and chlorine (CL) were studied for their sanitisation efficacy; concentrations of 100 mg/kg of PAA and 200 mg/kg of CL completely inactivated E. coli over the egg surface and also resulted in 2.58 and 2.38 log reduction in total viable counts (TVC), respectively. 6. The presence of virulence-associated shiga-like toxin (SLT1/2) and invasion E (INVE) genes and antimicrobial resistance among the emerging serotypes of pathogenic E. coli isolated from table eggs has public health implications. It underscores the need to implement better management practices across the production systems and marketing channels to produce E. coli-free wholesome eggs for consumers.

Characterization of Escherichia coli isolates from different fecal sources by means of classification tree analysis of fatty acid methyl ester (FAME) profiles.

PubMed

Seurinck, Sylvie; Deschepper, Ellen; Deboch, Bishaw; Verstraete, Willy; Siciliano, Steven

2006-03-01

Microbial source tracking (MST) methods need to be rapid, inexpensive and accurate. Unfortunately, many MST methods provide a wealth of information that is difficult to interpret by the regulators who use this information to make decisions. This paper describes the use of classification tree analysis to interpret the results of a MST method based on fatty acid methyl ester (FAME) profiles of Escherichia coli isolates, and to present results in a format readily interpretable by water quality managers. Raw sewage E. coli isolates and animal E. coli isolates from cow, dog, gull, and horse were isolated and their FAME profiles collected. Correct classification rates determined with leaveone-out cross-validation resulted in an overall low correct classification rate of 61%. A higher overall correct classification rate of 85% was obtained when the animal isolates were pooled together and compared to the raw sewage isolates. Bootstrap aggregation or adaptive resampling and combining of the FAME profile data increased correct classification rates substantially. Other MST methods may be better suited to differentiate between different fecal sources but classification tree analysis has enabled us to distinguish raw sewage from animal E. coli isolates, which previously had not been possible with other multivariate methods such as principal component analysis and cluster analysis.

Probable secondary transmission of antimicrobial-resistant Escherichia coli between people living with and without pets

PubMed Central

CHUNG, Yeon Soo; PARK, Young Kyung; PARK, Yong Ho; PARK, Kun Taek

2017-01-01

Companion animals are considered as one of the reservoirs of antimicrobial-resistant (AR) bacteria that can be cross-transmitted to humans. However, limited information is available on the possibility of AR bacteria originating from companion animals being transmitted secondarily from owners to non-owners sharing the same space. To address this issue, the present study investigated clonal relatedness among AR E. coli isolated from dog owners and non-owners in the same college classroom or household. Anal samples (n=48) were obtained from 14 owners and 34 non-owners; 31 E. coli isolates were collected (nine from owners and 22 from non-owners). Of 31 E. coli, 20 isolates (64.5%) were resistant to at least one antimicrobial, and 16 isolates (51.6%) were determined as multi-drug resistant E. coli. Six isolates (19.4%) harbored integrase genes (five harbored class I integrase gene and one harbored class 2 integrase gene, respectively). Pulsed-field gel electrophoretic analysis identified three different E. coli clonal sets among isolates, indicating that cross-transmission of AR E. coli can easily occur between owners and non-owners. The findings emphasize a potential risk of spread of AR bacteria originating from pets within human communities, once they are transferred to humans. Further studies are needed to evaluate the exact risk and identify the risk factors of secondarily transmission by investigating larger numbers of isolates from pets, their owners and non-owners in a community. PMID:28190823

Probable secondary transmission of antimicrobial-resistant Escherichia coli between people living with and without pets.

PubMed

Chung, Yeon Soo; Park, Young Kyung; Park, Yong Ho; Park, Kun Taek

2017-03-18

Companion animals are considered as one of the reservoirs of antimicrobial-resistant (AR) bacteria that can be cross-transmitted to humans. However, limited information is available on the possibility of AR bacteria originating from companion animals being transmitted secondarily from owners to non-owners sharing the same space. To address this issue, the present study investigated clonal relatedness among AR E. coli isolated from dog owners and non-owners in the same college classroom or household. Anal samples (n=48) were obtained from 14 owners and 34 non-owners; 31 E. coli isolates were collected (nine from owners and 22 from non-owners). Of 31 E. coli, 20 isolates (64.5%) were resistant to at least one antimicrobial, and 16 isolates (51.6%) were determined as multi-drug resistant E. coli. Six isolates (19.4%) harbored integrase genes (five harbored class I integrase gene and one harbored class 2 integrase gene, respectively). Pulsed-field gel electrophoretic analysis identified three different E. coli clonal sets among isolates, indicating that cross-transmission of AR E. coli can easily occur between owners and non-owners. The findings emphasize a potential risk of spread of AR bacteria originating from pets within human communities, once they are transferred to humans. Further studies are needed to evaluate the exact risk and identify the risk factors of secondarily transmission by investigating larger numbers of isolates from pets, their owners and non-owners in a community.

Prevalence and antimicrobial susceptibility of Escherichia coli O157 in beef at butcher shops and restaurants in central Ethiopia.

PubMed

Beyi, Ashenafi Feyisa; Fite, Akafete Teklu; Tora, Ephrem; Tafese, Asdesach; Genu, Tadele; Kaba, Tamirat; Beyene, Tariku Jibat; Beyene, Takele; Korsa, Mesula Geloye; Tadesse, Fanos; De Zutter, Lieven; Goddeeris, Bruno Maria; Cox, Eric

2017-03-03

Ethiopia bears the largest burden of foodborne diseases in Africa, and diarrheal diseases are the second leading causes of premature deaths. Enterohemorrhagic Escherichia coli O157 causes an asymptomatic infection to severe diarrhea and/or hemolytic-uremic syndrome in humans. A total of 440 beef carcass and in-contact surface swabs from 55 butcher shops and 85 minced beef samples from 40 restaurants in central Ethiopia were collected and examined for the presence of E. coli O157. Standard microbiological methods were used to isolate and identify E. coli O157 and to characterize the antimicrobial resistance of the isolates. E. coli O157 was detected in 4.5% carcass swabs (n = 5) and 3.6% cutting board swabs (n = 4) samples from butcher shops. E. coli O157 was not detected in any of the minced beef samples obtained from restaurants. All isolates (n = 9) were 100% susceptible to five drugs, but five isolates were resistant to amoxicillin, two isolates to streptomycin and three isolates to chloramphenicol. One isolate was resistant to two drugs and another to three drugs. The present study shows a low prevalence of E. coli O157 in beef sold at butcher shops. Nevertheless, given the low infective dose of this pathogen and the deep-rooted tradition of consuming raw or undercooked beef, the current prevalence should not be considered lightly from a public health perspective.

Characteristics of Quinolone Resistance in Escherichia coli Isolates from Humans, Animals, and the Environment in the Czech Republic

PubMed Central

Röderova, Magdalena; Halova, Dana; Papousek, Ivo; Dolejska, Monika; Masarikova, Martina; Hanulik, Vojtech; Pudova, Vendula; Broz, Petr; Htoutou-Sedlakova, Miroslava; Sauer, Pavel; Bardon, Jan; Cizek, Alois; Kolar, Milan; Literak, Ivan

2017-01-01

Escherichia coli is a common commensal bacterial species of humans and animals that may become a troublesome pathogen causing serious diseases. The aim of this study was to characterize the quinolone resistance phenotypes and genotypes in E. coli isolates of different origin from one area of the Czech Republic. E. coli isolates were obtained from hospitalized patients and outpatients, chicken farms, retailed turkeys, rooks wintering in the area, and wastewaters. Susceptibility of the isolates grown on the MacConkey agar with ciprofloxacin (0.05 mg/L) to 23 antimicrobial agents was determined. The presence of plasmid-mediated quinolone resistance (PMQR) and ESBL genes was tested by PCR and sequencing. Specific mutations in gyrA, gyrB, parC, and parE were also examined. Multilocus sequence typing and pulsed-field gel electrophoresis were performed to assess the clonal relationship. In total, 1050 E. coli isolates were obtained, including 303 isolates from humans, 156 from chickens, 105 from turkeys, 114 from the rooks, and 372 from wastewater samples. PMQR genes were detected in 262 (25%) isolates. The highest occurrence was observed in isolates from retailed turkey (49% of the isolates were positive) and inpatients (32%). The qnrS1 gene was the most common PMQR determinant identified in 146 (56%) followed by aac(6′)-Ib-cr in 77 (29%), qnrB19 in 41 (16%), and qnrB1 in 9 (3%) isolates. All isolates with high level of ciprofloxacin resistance (>32 mg/L) carried double or triple mutations in gyrA combined with single or double mutations in parC. The most frequently identified substitutions were Ser(83)Leu; Asp(87)Asn in GyrA, together with Ser(80)Ile, or Glu(84)Val in ParC. Majority of these isolates showed resistance to beta-lactams and multiresistance phenotype was found in 95% isolates. Forty-eight different sequence types among 144 isolates analyzed were found, including five major clones ST131 (26), ST355 (19), ST48 (13), ST95 (10), and ST10 (5). No isolates sharing 100% relatedness and originating from different areas were identified. In conclusion, our study identified PMQR genes in E. coli isolates in all areas studied, including highly virulent multiresistant clones such as ST131 producing CTX-M-15 beta-lactamases. PMID:28119674

Dynamics of extended-spectrum cephalosporin resistance in pathogenic Escherichia coli isolated from diseased pigs in Quebec, Canada.

PubMed

Jahanbakhsh, Seyedehameneh; Smith, Matthew G; Kohan-Ghadr, Hamid-Reza; Letellier, Ann; Abraham, Sam; Trott, Darren J; Fairbrother, John Morris

2016-08-01

The aim of this study was to investigate the evolution with time of ceftiofur-resistant Escherichia coli clinical isolates from pigs in Québec, Canada, between 1997 and 2012 with respect to pathotypes, clones and antimicrobial resistance. Eighty-five ceftiofur-resistant E. coli isolates were obtained from the OIE (World Organisation for Animal Health) Reference Laboratory for Escherichia coli. The most prevalent pathovirotypes were enterotoxigenic E. coli (ETEC):F4 (40%), extraintestinal pathogenic E. coli (ExPEC) (16.5%) and Shiga toxin-producing E. coli (STEC):F18 (8.2%). Susceptibility testing to 15 antimicrobial agents revealed a high prevalence of resistance to 13 antimicrobials, with all isolates being multidrug-resistant. blaCMY-2 (96.5%) was the most frequently detected β-lactamase gene, followed by blaTEM (49.4%) and blaCTX-M (3.5%). Pulsed-field gel electrophoresis (PFGE) applied to 45 representative E. coli isolates revealed that resistance to ceftiofur is spread both horizontally and clonally. In addition, the emergence of extended-spectrum β-lactamase-producing E. coli isolates carrying blaCTX-M was observed in 2011 and 2012 in distinct clones. The most predominant plasmid incompatibility (Inc) groups were IncFIB, IncI1, IncA/C and IncFIC. Resistance to gentamicin, kanamycin and chloramphenicol as well as the frequency of blaTEM and IncA/C significantly decreased over the study period, whereas the frequency of IncI1 and multidrug resistance to seven antimicrobial categories significantly increased. These findings reveal that extended-spectrum cephalosporin-resistant porcine E. coli isolates in Québec belong to several different clones with diverse antimicrobial resistance patterns and plasmids. Furthermore, blaCMY-2 was the major β-lactamase gene in these isolates. From 2011, we report the emergence of blaCTX-M in distinct clones. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Detection and characterization of fecal verotoxin-producing Escherichia coli from healthy cattle.

PubMed Central

Montenegro, M A; Bülte, M; Trumpf, T; Aleksić, S; Reuter, G; Bulling, E; Helmuth, R

1990-01-01

Verotoxin-producing Escherichia coli isolates from feces of healthy cattle were identified by DNA hybridization with verotoxin 1- and verotoxin 2-specific gene probes. Among 259 animals investigated, 28 (10.8%) were found to carry verotoxin-producing E. coli strains. Characterization of the verotoxin-producing isolates revealed a heterogeneous population in terms of serotype and toxin type. Nearly 40% of the strains belonged to serogroups known to be pathogenic for humans, i.e., O22, O39, O82, O91, O113, O116, O126, and O136. Two isolates from different bulls were identified as serotype O157:H7. Results obtained in this study indicate that cattle may be an important source of verotoxigenic E. coli involved in human disease. Images PMID:2199502

[Multilocus Sequence Typing analysis of human Campylobacter coli in Granada (Spain)].

PubMed

Carrillo-Ávila, J A; Sorlózano-Puerto, A; Pérez-Ruiz, M; Gutiérrez-Fernández, J

2016-12-01

Different subtypes of Campylobacter spp. have been associated with diarrhoea and a Multilocus Sequence Typing (MLST) method has been performed for subtyping. In the present work, MLST was used to analyse the genetic diversity of eight strains of Campylobacter coli. Nineteen genetic markers were amplified for MLST analysis: AnsB, DmsA, ggt, Cj1585c, CJJ81176-1367/1371, Tlp7, cj1321-cj1326, fucP, cj0178, cj0755/cfrA, ceuE, pldA, cstII, cstIII. After comparing the obtained sequences with the Campylobacter MLST database, the allele numbers, sequence types (STs) and clonal complexes (CCs) were assigned. The 8 C. coli isolates yielded 4 different STs belonging to 2 CCs. Seven isolates belong to ST-828 clonal complex and only one isolate belong to ST-21. Two samples came from the same patient, but were isolated in two different periods of time. MLST can be useful for taxonomic characterization of C. coli isolates.

Virulence gene content in Escherichia coli isolates from poultry flocks with clinical signs of colibacillosis in Brazil.

PubMed

De Carli, Silvia; Ikuta, Nilo; Lehmann, Fernanda Kieling Moreira; da Silveira, Vinicius Proença; de Melo Predebon, Gabriela; Fonseca, André Salvador Kazantzi; Lunge, Vagner Ricardo

2015-11-01

Escherichia coli is a commensal bacterium of the bird's intestinal tract, but it can invade different tissues resulting in systemic symptoms (colibacillosis). This disease occurs only when the E. coli infecting strain presents virulence factors (encoded by specific genes) that enable the adhesion and proliferation in the host organism. Thus, it is important to differentiate pathogenic (APEC, avian pathogenic E. coli) and non-pathogenic or fecal (AFEC, avian fecal E. coli) isolates. Previous studies analyzed the occurrence of virulence factors in E. coli strains isolated from birds with colibacillosis, demonstrating a high frequency of the bacterial genes cvaC, iroN, iss, iutA, sitA, tsh, fyuA, irp-2, ompT and hlyF in pathogenic strains. The aim of the present study was to evaluate the occurrence and frequency of these virulence genes in E. coli isolated from poultry flocks in Brazil. A total of 138 isolates of E. coli was obtained from samples of different tissues and/or organs (spleen, liver, kidney, trachea, lungs, skin, ovary, oviduct, intestine, cloaca) and environmental swabs collected from chicken and turkey flocks suspected to have colibacillosis in farms from the main Brazilian producing regions. Total DNA was extracted and the 10 virulence genes were detected by traditional and/or real-time PCR. At least 11 samples of each gene were sequenced and compared to reference strains. All 10 virulence factors were detected in Brazilian E. coli isolates, with frequencies ranging from 39.9% (irp-2) to 68.8% (hlyF and sitA). Moreover, a high nucleotide similarity (over 99%) was observed between gene sequences of Brazilian isolates and reference strains. Seventy-nine isolates were defined as pathogenic (APEC) and 59 as fecal (AFEC) based on previously described criteria. In conclusion, the main virulence genes of the reference E. coli strains are also present in isolates associated with colibacillosis in Brazil. The analysis of this set of virulence factors can be used to differentiate between APEC and AFEC isolates in Brazil. © 2015 Poultry Science Association Inc.

Frequency of iss and irp2 genes by PCR method in Escherichia coli isolated from poultry with colibacillosis in comparison with healthy chicken in poultry farms of Zabol, South East of Iran.

PubMed

Sadeghi Bonjar, M S; Salari, S; Jahantigh, M; Rashki, A

2017-03-01

There is no special trait for differentiation of Avian Pathogenic Escherichia coli from Avian Fecal Escherichia coli. This investigation is aimed, as a case control study, to evaluate and compare the frequency of iss and irp2 in 43 AFEC strains and also 40 and 56 E. coli strains isolated from the liver and kidney of chickens with colibacillosis, respectively, farmed in Zabol, as a border region of Iran, by PCR. 86.9% and 37.2% of isolates collected from chickens with colibacillosis and feces samples obtained from healthy chickens were positive for iss gene, respectively (P<0.05). On average, 59.3% of E. coli strains isolated from colibacillosis have irp2 gene while 27.9% of isolates from the feces of healthy birds were positive (P<0.05). 52.15% of isolates from colibacillosis and 19.62% of isolates from healthy chicken feces were positive for both genes, with statistical significant difference (p<0.05). This marked difference in the distribution of iss and irp2 genes makes these two genes good markers to differentiate AFEC and APEC strains especially in Sistan region to improve colibacillosis control measurements.

Antibiotic resistance profile and virulence genes of uropathogenic Escherichia coli isolates in relation to phylogeny.

PubMed

Adib, N; Ghanbarpour, R; Solatzadeh, H; Alizade, H

2014-03-01

Escherichia coli (E. coli) strains are the major cause of urinary tract infections (UTI) and belong to the large group of extra-intestinal pathogenic E. coli. The purposes of this study were to determine the antibiotic resistance profile, virulence genes and phylogenetic background of E. coli isolates from UTI cases. A total of 137 E. coli isolates were obtained from UTI samples. The antimicrobial susceptibility of confirmed isolates was determined by disk diffusion method against eight antibiotics. The isolates were examined to determine the presence and prevalence of selected virulence genes including iucD, sfa/focDE, papEF and hly. ECOR phylo-groups of isolates were determined by detection of yjaA and chuA genes and fragment TspE4.C2. The antibiogram results showed that 71% of the isolates were resistant to cefazolin, 60.42% to co-trimoxazole, 54.16% to nalidixic acid, 36.45% to gentamicin, 29.18% to ciprofloxacin, 14.58% to cefepime, 6.25% to nitrofurantoin and 0.00% to imipenem. Twenty-two antibiotic resistance patterns were observed among the isolates. Virulence genotyping of isolates revealed that 58.39% isolates had at least one of the four virulence genes. The iucD gene was the most prevalent gene (43.06%). The other genes including sfa/focDE, papEF and hly genes were detected in 35.76%, 18.97% and 2.18% isolates, respectively. Nine combination patterns of the virulence genes were detected in isolates. Phylotyping of 137 isolates revealed that the isolates fell into A (45.99%), B1 (13.14%), B2 (19.71%) and D (21.16%) groups. Phylotyping of multidrug resistant isolates indicated that these isolates are mostly in A (60.34%) and D (20.38%) groups. In conclusion, the isolates that possessed the iucD, sfa/focDE, papEF and hly virulence genes mostly belonged to A and B2 groups, whereas antibiotic resistant isolates were in groups A and D. Escherichia coli strains carrying virulence factors and antibiotic resistance are distributed in specific phylogenetic background.

Antimicrobial activity of yeasts against some pathogenic bacteria

PubMed Central

Younis, Gamal; Awad, Amal; Dawod, Rehab E.; Yousef, Nehal E.

2017-01-01

Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR) for detection of khs (kievitone hydratase) and pelA (pectate degrading enzyme)genes. Results: The recovery rate of yeasts from sausage was 20% (2/10) followed by kareish cheese, processed cheese, and butter 10% (1/10) each as well as raw milk 9% (9/100), and fruit yoghurt 30% (6/20). Different yeast species were recovered, namely, Candida kefyr (5 isolates), Saccharomyces cerevisiae (4 isolates), Candida intermedia (3 isolates), Candida tropicalis (2 isolates), Candida lusitaniae (2 isolates), and Candida krusei (1 isolate). khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food. PMID:28919693

Antimicrobial susceptibility and genetic characterization of Escherichia coli recovered from frozen game meat.

PubMed

Mateus-Vargas, Rafael H; Atanassova, Viktoria; Reich, Felix; Klein, Günter

2017-05-01

The increasing number of antimicrobial resistant Enterobacteriaceae both in veterinary and human medicine, the dissemination of these bacteria in several environments and their possible repercussions on human health is causing concern. Game meat is usually seen as free of antimicrobial resistant bacteria. The objective of this study was to evaluate the current antimicrobial susceptibility status in generic Escherichia coli isolated from packed frozen game meat from a game handling establishment in Germany. A total of 229 E. coli isolates were obtained from cuts of red deer, roe deer and wild boar. The susceptibility to 12 antimicrobial agents was evaluated by a broth microdilution method according to ISO 20776-1:2006. Minimal Inhibitory Concentration (MIC) values were compared to breakpoints and cut-off values published by the EUCAST. Isolates showing MICs above the reference values were further studied for associated resistance determinants and phylogrouping by PCR. Overall, 16 E. coli isolates (7.0%) showed resistance (microbiological or clinical) to at least one antimicrobial agent tested. Clinical resistance was recorded to ampicillin (5/229) and chloramphenicol (4/229), whereas the MIC of 9 isolates exceeded the epidemiological cut-off value for doxycycline. One of the ampicillin-resistant isolates showed resistance to the β-lactam antibiotic derivatives tested, cephalosporines and aztreonam. Three of 9 non-wild-type isolates for doxycycline were positive for tet (B) genes. The ß-lactam-resistant isolate was found to harbour bla CTX-M-1 gene. These data show a low prevalence of resistant E. coli in packed game meat compared to studies on conventional meat. Although isolates obtained in this study may also be originating from the processing environment and not necessarily from animals, based on our results, it is important to monitor the development of antimicrobial resistance in game animals and products in order to identify future threats for the consumers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Absence of CTX-M Enzymes but High Prevalence of Clones, Including Clone ST131, among Fecal Escherichia coli Isolates from Healthy Subjects Living in the Area of Paris, France▿

PubMed Central

Leflon-Guibout, Véronique; Blanco, Jorge; Amaqdouf, Karim; Mora, Azucena; Guize, Louis; Nicolas-Chanoine, Marie-Hélène

2008-01-01

Quinolone-resistant and CTX-M-15-producing Escherichia coli isolates belonging to clone ST131 have been reported in the community. This study was designed to identify these E. coli isolates in the stools of 332 independent healthy subjects living in the area of Paris, France. Stools were plated on media without antibiotics, in order to obtain the dominant (Dm) fecal E. coli strain, and with nalidixic acid (NAL) and cefotaxime. Quinolone susceptibility, phylogenetic groups, and molecular profiles, including multilocus sequence types (ST), were determined for all NAL-resistant (NAL-R) isolates. Groups were also determined for the Dm strains from participants with NAL-R isolates and from a subgroup without NAL-R isolates. All B2 isolates were typed; pulsed-field gel electrophoresis was performed for the ST131 isolates, and the results were compared with those for intercontinental clone ST131. Two participants (0.6%) had extended-spectrum β-lactamase-producing (SHV-2, TEM-52) fecal E. coli isolates, and 51 (15%) had NAL-R isolates; 51% of NAL-R isolates belonged to phylogenetic group A, 31% to group D, 16% to group B2, and 2% to group B1. The Dm strain was NAL-R in 3.3% of the 332 subjects. Forty-nine percent of the NAL-R isolates belonged to clones: ST10 and ST606 for group A isolates, ST117 and ST393 for group D isolates. Of all B2 isolates studied from 100 subjects (8 NAL-R strains; 19 NAL-susceptible dominant strains), 52% belonged to three clones: ST131 (n = 7), ST95 (n = 4), and ST141 (n = 3). This is the first study to show the presence of fecal E. coli isolates of clone ST131 in 7% of independent healthy subjects not colonized by CTX-M-15-producing isolates. PMID:18842941

Detection of Escherichia coli sequence type 131 by matrix-assisted laser desorption ionization time-of-flight mass spectrometry: implications for infection control policies?

PubMed

Lafolie, J; Sauget, M; Cabrolier, N; Hocquet, D; Bertrand, X

2015-07-01

Sequence type 131 (ST131) is a predominant lineage among extraintestinal pathogenic Escherichia coli. It plays a major role in the worldwide dissemination of extended-spectrum β-lactamase (ESBL)-producing E. coli. The ST131 pandemic is mainly the result of clonal expansion of the single well-adapted subclone H30-Rx, which is acquired in hospitals more frequently than other ESBL-producing E. coli clones. To develop a rapid method using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify ST131 for infection control purposes. Peak biomarkers of ST131 were identified from the mass spectrum profiles of 109 E. coli isolates (including 50 ST131 isolates). The models accurately identified ST131 isolates from mass spectrum profiles obtained with and without protein extraction. The rapid identification of ST131 isolates with MALDI-TOF MS can be easily implemented in the laboratory, and could help to target infection control measures in patients carrying multi-drug-resistant E. coli that are more likely to spread. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Characterization of Resistance Patterns and Detection of Apramycin Resistance Genes in Escherichia coli Isolated from Chicken Feces and Houseflies after Apramycin Administration.

PubMed

Zhang, Anyun; Li, Yunxia; Guan, Zhongbin; Tuo, Hongmei; Liu, Dan; Yang, Yanxian; Xu, Changwen; Lei, Changwei; Wang, Hongning

2018-01-01

The aim of this study was to evaluate the influence of apramycin administration on the development of antibiotic resistance in Escherichia coli ( E. coli ) strains isolated from chicken feces and houseflies under field conditions. Chickens in the medicated group ( n = 25,000) were given successive prophylactic doses (0.5 mg/l) of apramycin in their drinking water from Days 1 to 5, while no antibiotics were added to the un-medicated groups drinking water ( n = 25,000). Over 40 days, a total of 1170 E. coli strains were isolated from fecal samples obtained from medicated and un-medicated chickens and houseflies from the same chicken farm. Apramycin MIC90 values for E. coli strains obtained from the medicated group increased 32-128 times from Days 2 to 6 (256-1024 μg/ml) when compared to those on Day 0 (8 μg/ml). Strains isolated from un-medicated chickens and houseflies had consistently low MIC90 values (8-16 μg/ml) during the first week, but showed a dramatic increase from Days 8 to 10 (128-1024 μg/ml). The apramycin resistance gene aac(3)-IV was detected in E. coli strains from medicated ( n = 71), un-medicated ( n = 32), and housefly groups ( n = 42). All strains positive for aac(3)-IV were classified into 12 pulsed-field gel electrophoresis (PFGE) types. PFGE types A, E, and G were the predominant types in both the medicated and housefly groups, suggesting houseflies play an important role in spreading E. coli -resistant strains. Taken together, our study revealed that apramycin administration could facilitate the occurrence of apramycin-resistant E. coli and the apramycin resistance gene acc(3)-IV . In turn, these strains could be transmitted by houseflies, thus increasing the potential risk of spreading multi-drug-resistant E. coli to the public.

Characterization of Resistance Patterns and Detection of Apramycin Resistance Genes in Escherichia coli Isolated from Chicken Feces and Houseflies after Apramycin Administration

PubMed Central

Zhang, Anyun; Li, Yunxia; Guan, Zhongbin; Tuo, Hongmei; Liu, Dan; Yang, Yanxian; Xu, Changwen; Lei, Changwei; Wang, Hongning

2018-01-01

The aim of this study was to evaluate the influence of apramycin administration on the development of antibiotic resistance in Escherichia coli (E. coli) strains isolated from chicken feces and houseflies under field conditions. Chickens in the medicated group (n = 25,000) were given successive prophylactic doses (0.5 mg/l) of apramycin in their drinking water from Days 1 to 5, while no antibiotics were added to the un-medicated groups drinking water (n = 25,000). Over 40 days, a total of 1170 E. coli strains were isolated from fecal samples obtained from medicated and un-medicated chickens and houseflies from the same chicken farm. Apramycin MIC90 values for E. coli strains obtained from the medicated group increased 32–128 times from Days 2 to 6 (256–1024 μg/ml) when compared to those on Day 0 (8 μg/ml). Strains isolated from un-medicated chickens and houseflies had consistently low MIC90 values (8–16 μg/ml) during the first week, but showed a dramatic increase from Days 8 to 10 (128–1024 μg/ml). The apramycin resistance gene aac(3)-IV was detected in E. coli strains from medicated (n = 71), un-medicated (n = 32), and housefly groups (n = 42). All strains positive for aac(3)-IV were classified into 12 pulsed-field gel electrophoresis (PFGE) types. PFGE types A, E, and G were the predominant types in both the medicated and housefly groups, suggesting houseflies play an important role in spreading E. coli-resistant strains. Taken together, our study revealed that apramycin administration could facilitate the occurrence of apramycin-resistant E. coli and the apramycin resistance gene acc(3)-IV. In turn, these strains could be transmitted by houseflies, thus increasing the potential risk of spreading multi-drug-resistant E. coli to the public. PMID:29535694

Neem (Azadirachta indica A. Juss) Oil to Tackle Enteropathogenic Escherichia coli

PubMed Central

Del Serrone, Paola; Nicoletti, Marcello

2015-01-01

Neem (Azadirachta indica A. Juss) oil (NO) was assayed against forty-eight isolates of Escherichia coli by standardised disc diffusion test and microdilution test. By molecular biology characterization, fourteen isolates resulted in diarrheagenic E. coli with sixteen primer pairs that specifically amplify unique sequences of virulence genes and of 16S rRNA. The NO showed biological activity against all isolates. The bacterial growth inhibition zone by disc diffusion method (100 µL NO) ranged between 9.50 ± 0.70 and 30.00 ± 1.00 mm. The antibacterial activity was furthermore determined at lower NO concentrations (1 : 10–1 : 10,000). The percent of growth reduction ranged between 23.71 ± 1.00 and 99.70 ± 1.53. The highest bacterial growth reduction was 1 : 10 NO concentration with 50 µL of bacterial suspension (ca. 1 × 106 CFU/mL). There is significant difference between the antibacterial activities against pathogenic and nonpathogenic E. coli, as well as NO and ciprofloxacin activities. Viable cells after the different NO concentration treatments were checked by molecular biology assay using PMA dye. On the basis of the obtained results, NO counteracts E. coli and also influences the virulence of E. coli viable cells after NO treatment. The NO metabolomic composition was obtained using fingerprint HPTLC. PMID:26064900

Neem (Azadirachta indica A. Juss) Oil to Tackle Enteropathogenic Escherichia coli.

PubMed

Del Serrone, Paola; Toniolo, Chiara; Nicoletti, Marcello

2015-01-01

Neem (Azadirachta indica A. Juss) oil (NO) was assayed against forty-eight isolates of Escherichia coli by standardised disc diffusion test and microdilution test. By molecular biology characterization, fourteen isolates resulted in diarrheagenic E. coli with sixteen primer pairs that specifically amplify unique sequences of virulence genes and of 16S rRNA. The NO showed biological activity against all isolates. The bacterial growth inhibition zone by disc diffusion method (100 µL NO) ranged between 9.50 ± 0.70 and 30.00 ± 1.00 mm. The antibacterial activity was furthermore determined at lower NO concentrations (1 : 10-1 : 10,000). The percent of growth reduction ranged between 23.71 ± 1.00 and 99.70 ± 1.53. The highest bacterial growth reduction was 1 : 10 NO concentration with 50 µL of bacterial suspension (ca. 1 × 10(6) CFU/mL). There is significant difference between the antibacterial activities against pathogenic and nonpathogenic E. coli, as well as NO and ciprofloxacin activities. Viable cells after the different NO concentration treatments were checked by molecular biology assay using PMA dye. On the basis of the obtained results, NO counteracts E. coli and also influences the virulence of E. coli viable cells after NO treatment. The NO metabolomic composition was obtained using fingerprint HPTLC.

Comparative Genomic Analysis of Escherichia coli O157:H7 Isolated from Super-Shedder and Low-Shedder Cattle

PubMed Central

Munns, Krysty D.; Zaheer, Rahat; Xu, Yong; Stanford, Kim; Laing, Chad R.; Gannon, Victor P. J.; Selinger, L. Brent; McAllister, Tim A.

2016-01-01

Cattle are the primary reservoir of the foodborne pathogen Escherichia coli O157:H7, with the concentration and frequency of E. coli O157:H7 shedding varying substantially among individual hosts. The term ‘‘super-shedder” has been applied to cattle that shed ≥104 cfu E. coli O157:H7/g of feces. Super-shedders have been reported to be responsible for the majority of E. coli O157:H7 shed into the environment. The objective of this study was to determine if there are phenotypic and/or genotypic differences between E. coli O157:H7 isolates obtained from super-shedder compared to low-shedder cattle. From a total of 784 isolates, four were selected from low-shedder steers and six isolates from super-shedder steers (4.01–8.45 log cfu/g feces) for whole genome sequencing. Isolates were phage and clade typed, screened for substrate utilization, pH sensitivity, virulence gene profiles and Stx bacteriophage insertion (SBI) sites. A range of 89–2473 total single nucleotide polymorphisms (SNPs) were identified when sequenced strains were compared to E. coli O157:H7 strain Sakai. More non-synonymous SNP mutations were observed in low-shedder isolates. Pan-genomic and SNPs comparisons did not identify genetic segregation between super-shedder or low-shedder isolates. All super-shedder isolates and 3 of 4 of low-shedder isolates were typed as phage type 14a, SBI cluster 3 and SNP clade 2. Super-shedder isolates displayed increased utilization of galactitol, thymidine and 3-O-β-D-galactopyranosyl-D-arabinose when compared to low-shedder isolates, but no differences in SNPs were observed in genes encoding for proteins involved in the metabolism of these substrates. While genetic traits specific to super-shedder isolates were not identified in this study, differences in the level of gene expression or genes of unknown function may still contribute to some strains of E. coli O157:H7 reaching high densities within bovine feces. PMID:27018858

Comparative Genomic Analysis of Escherichia coli O157:H7 Isolated from Super-Shedder and Low-Shedder Cattle.

PubMed

Munns, Krysty D; Zaheer, Rahat; Xu, Yong; Stanford, Kim; Laing, Chad R; Gannon, Victor P J; Selinger, L Brent; McAllister, Tim A

2016-01-01

Cattle are the primary reservoir of the foodborne pathogen Escherichia coli O157:H7, with the concentration and frequency of E. coli O157:H7 shedding varying substantially among individual hosts. The term ''super-shedder" has been applied to cattle that shed ≥10(4) cfu E. coli O157:H7/g of feces. Super-shedders have been reported to be responsible for the majority of E. coli O157:H7 shed into the environment. The objective of this study was to determine if there are phenotypic and/or genotypic differences between E. coli O157:H7 isolates obtained from super-shedder compared to low-shedder cattle. From a total of 784 isolates, four were selected from low-shedder steers and six isolates from super-shedder steers (4.01-8.45 log cfu/g feces) for whole genome sequencing. Isolates were phage and clade typed, screened for substrate utilization, pH sensitivity, virulence gene profiles and Stx bacteriophage insertion (SBI) sites. A range of 89-2473 total single nucleotide polymorphisms (SNPs) were identified when sequenced strains were compared to E. coli O157:H7 strain Sakai. More non-synonymous SNP mutations were observed in low-shedder isolates. Pan-genomic and SNPs comparisons did not identify genetic segregation between super-shedder or low-shedder isolates. All super-shedder isolates and 3 of 4 of low-shedder isolates were typed as phage type 14a, SBI cluster 3 and SNP clade 2. Super-shedder isolates displayed increased utilization of galactitol, thymidine and 3-O-β-D-galactopyranosyl-D-arabinose when compared to low-shedder isolates, but no differences in SNPs were observed in genes encoding for proteins involved in the metabolism of these substrates. While genetic traits specific to super-shedder isolates were not identified in this study, differences in the level of gene expression or genes of unknown function may still contribute to some strains of E. coli O157:H7 reaching high densities within bovine feces.

Role of CD14 in responses to clinical isolates of Escherichia coli: effects of K1 capsule expression.

PubMed

Metkar, Shalaka; Awasthi, Shanjana; Denamur, Erick; Kim, Kwang Sik; Gangloff, Sophie C; Teichberg, Saul; Haziot, Alain; Silver, Jack; Goyert, Sanna M

2007-11-01

Severe bacterial infections leading to sepsis or septic shock can be induced by bacteria that utilize different factors to drive pathogenicity and/or virulence, leading to disease in the host. One major factor expressed by all clinical isolates of gram-negative bacteria is lipopolysaccharide (LPS); a second factor expressed by some Escherichia coli strains is a K1 polysaccharide capsule. To determine the role of the CD14 LPS receptor in the pathogenic effects of naturally occurring E. coli, the responses of CD14-/- and CD14+/+ mice to three different isolates of E. coli obtained from sepsis patients were compared; two isolates express both smooth LPS and the K1 antigen, while the third isolate expresses only LPS and is negative for K1. An additional K1-positive isolate obtained from a newborn with meningitis and a K1-negative isogenic mutant of this strain were also used for these studies. CD14-/- mice were resistant to the lethal effects of the K1-negative isolates. This resistance was accompanied by significantly lower levels of systemic tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) in these mice than in CD14+/+ mice, enhanced clearance of the bacteria, and significantly fewer additional gross symptoms. In contrast, CD14-/- mice were as sensitive as CD14+/+ mice to the lethal effects of the K1-positive isolates, even though they had significantly lower levels of TNF-alpha and IL-6 than CD14+/+ mice. These studies show that different bacterial isolates can use distinctly different mechanisms to cause disease and suggest that new, nonantibiotic therapeutics need to be directed against multiple targets.

Insights into the evolution of pathogenicity of Escherichia coli from genomic analysis of intestinal E. coli of Marmota himalayana in Qinghai–Tibet plateau of China

PubMed Central

Lu, Shan; Jin, Dong; Wu, Shusheng; Yang, Jing; Lan, Ruiting; Bai, Xiangning; Liu, Sha; Meng, Qiong; Yuan, Xuejiao; Zhou, Juan; Pu, Ji; Chen, Qiang; Dai, Hang; Hu, Yuanyuan; Xiong, Yanwen; Ye, Changyun; Xu, Jianguo

2016-01-01

Escherichia coli is both of a widespread harmless gut commensal and a versatile pathogen of humans. Domestic animals are a well-known reservoir for pathogenic E. coli. However, studies of E. coli populations from wild animals that have been separated from human activities had been very limited. Here we obtained 580 isolates from intestinal contents of 116 wild Marmot Marmota himalayana from Qinghai–Tibet plateau, China, with five isolates per animal. We selected 125 (hereinafter referred to as strains) from the 580 isolates for genome sequencing, based on unique pulse field gel electrophoresis patterns and at least one isolate per animal. Whole genome sequence analysis revealed that all 125 strains carried at least one and the majority (79.2%) carried multiple virulence genes based on the analysis of 22 selected virulence genes. In particular, the majority of the strains carried virulence genes from different pathovars as potential 'hybrid pathogens'. The alleles of eight virulence genes from the Marmot E. coli were found to have diverged earlier than all known alleles from human and other animal E. coli. Phylogenetic analysis of the 125 Marmot E. coli genomes and 355 genomes selected from 1622 human and other E. coli strains identified two new phylogroups, G and H, both of which diverged earlier than the other phylogroups. Eight of the 12 well-known pathogenic E. coli lineages were found to share a most recent common ancestor with one or more Marmot E. coli strains. Our results suggested that the intestinal E. coli of the Marmots contained a diverse virulence gene pool and is potentially pathogenic to humans. These findings provided a new understanding of the evolutionary origin of pathogenic E. coli. PMID:27924811

Insights into the evolution of pathogenicity of Escherichia coli from genomic analysis of intestinal E. coli of Marmota himalayana in Qinghai-Tibet plateau of China.

PubMed

Lu, Shan; Jin, Dong; Wu, Shusheng; Yang, Jing; Lan, Ruiting; Bai, Xiangning; Liu, Sha; Meng, Qiong; Yuan, Xuejiao; Zhou, Juan; Pu, Ji; Chen, Qiang; Dai, Hang; Hu, Yuanyuan; Xiong, Yanwen; Ye, Changyun; Xu, Jianguo

2016-12-07

Escherichia coli is both of a widespread harmless gut commensal and a versatile pathogen of humans. Domestic animals are a well-known reservoir for pathogenic E. coli. However, studies of E. coli populations from wild animals that have been separated from human activities had been very limited. Here we obtained 580 isolates from intestinal contents of 116 wild Marmot Marmota himalayana from Qinghai-Tibet plateau, China, with five isolates per animal. We selected 125 (hereinafter referred to as strains) from the 580 isolates for genome sequencing, based on unique pulse field gel electrophoresis patterns and at least one isolate per animal. Whole genome sequence analysis revealed that all 125 strains carried at least one and the majority (79.2%) carried multiple virulence genes based on the analysis of 22 selected virulence genes. In particular, the majority of the strains carried virulence genes from different pathovars as potential 'hybrid pathogens'. The alleles of eight virulence genes from the Marmot E. coli were found to have diverged earlier than all known alleles from human and other animal E. coli. Phylogenetic analysis of the 125 Marmot E. coli genomes and 355 genomes selected from 1622 human and other E. coli strains identified two new phylogroups, G and H, both of which diverged earlier than the other phylogroups. Eight of the 12 well-known pathogenic E. coli lineages were found to share a most recent common ancestor with one or more Marmot E. coli strains. Our results suggested that the intestinal E. coli of the Marmots contained a diverse virulence gene pool and is potentially pathogenic to humans. These findings provided a new understanding of the evolutionary origin of pathogenic E. coli.

Genetic Characterization of Atypical Enteropathogenic Escherichia coli Isolates from Ewes' Milk, Sheep Farm Environments, and Humans by Multilocus Sequence Typing and Pulsed-Field Gel Electrophoresis

PubMed Central

Otero, Verónica; Rodríguez-Calleja, José-María; Otero, Andrés; García-López, María-Luisa

2013-01-01

A collection of 81 isolates of enteropathogenic Escherichia coli (EPEC) was obtained from samples of bulk tank sheep milk (62 isolates), ovine feces (4 isolates), sheep farm environment (water, 4 isolates; air, 1 isolate), and human stool samples (9 isolates). The strains were considered atypical EPEC organisms, carrying the eae gene without harboring the pEAF plasmid. Multilocus sequence typing (MLST) was carried out with seven housekeeping genes and 19 sequence types (ST) were detected, with none of them having been previously reported for atypical EPEC. The most frequent ST included 41 strains isolated from milk and human stool samples. Genetic typing by pulsed-field gel electrophoresis (PFGE) resulted in 57 patterns which grouped in 24 clusters. Comparison of strains isolated from the different samples showed phylogenetic relationships between milk and human isolates and also between milk and water isolates. The results obtained show a possible risk for humans due to the presence of atypical EPEC in ewes' milk and suggest a transmission route for this emerging pathogen through contaminated water. PMID:23872571

[Identification of resistance and susceptibility to cefotaxime in EHEC O121 strains isolated from an outbreak at two nurseries].

PubMed

Kikuchi, Koji; Ueno, Hiroyuki; Tomari, Kentaro; Kobori, Sumie; Kaetsu, Akihiko; Miyazaki, Motonobu

2014-07-01

A Shiga toxin 2 producing enterohemorrhagic Escherichia coli (EHEC) O121: H19 was isolated from a 2-year-old child who attending a nursery. An EHEC O121 outbreak in two nurseries (A, B), involving a total of 17 infected persons including 12 children, was revealed through contact investigation. The symptoms of all infected persons were almost all mild, and no one developed the hemolytic uremic syndrome. The combination use of desoxycholate-hydrogen sulfide-lactose (DHL) and CHROMagar STEC as selective isolation media was employed for efficient fecal examination. Nursery A and nursery B were combined as one group after the outbreak in nursery A was confirmed. As a result, EHEC O121 infected persons were also detected in children from nursery B. The 17 strains of EHEC O121 obtained from the total population showed almost the same pulsed-gel electrophoresis (PFGE) pattern, suggesting that these strains were very closely related. However, 13 of these 17 strains obtained from nursery A were susceptible to cefotaxime, whereas the remaining 4 strains obtained from nursery B showed cefotaxime resistance. A cefotaxime resistant Escherichia coli (E. coli) O86 strain was isolated in the stool specimen from a child who had been infected with the cefotaxime resistant EHEC O121. Both the cefotaxime resistant EHEC O121 and E. coli O86 had the same drug resistant gene (bla(CTX-M-1) group). The child was the index case of these 4 later cases and had received no antibiotics therapy prior to the laboratory examination. These findings suggested the possibility that an EHEC O121 strain had acquired a drug resistant gene from E. coli O86 in the digestive tract of the child.

Occurrence of Diarrheagenic Virulence Genes and Genetic Diversity in Escherichia coli Isolates from Fecal Material of Various Avian Hosts in British Columbia, Canada

PubMed Central

Mazumder, Asit

2014-01-01

Contamination of surface water by fecal microorganisms originating from human and nonhuman sources is a public health concern. In the present study, Escherichia coli isolates (n = 412) from the feces of various avian host sources were screened for various virulence genes: stx1 and stx2 (Shiga toxin-producing E. coli [STEC]), eae (enteropathogenic E. coli [EPEC]), est-h, est-p, and elt (encoding heat-stable toxin [ST] variants STh and STp and heat-labile toxin [LT], respectively) (enterotoxigenic E. coli [ETEC]), and ipaH (enteroinvasive E. coli [EIEC]). None of the isolates were found to be positive for stx1, while 23% (n = 93) were positive for only stx2, representing STEC, and 15% (n = 63) were positive for only eae, representing EPEC. In addition, five strains obtained from pheasant were positive for both stx2 and eae and were confirmed as non-O157 by using an E. coli O157 rfb (rfbO157) TaqMan assay. Isolates positive for the virulence genes associated with ETEC and EIEC were not detected in any of the hosts. The repetitive element palindromic PCR (rep-PCR) fingerprint analysis identified 143 unique fingerprints, with an overall Shannon diversity index of 2.36. Multivariate analysis of variance (MANOVA) showed that the majority of the STEC and EPEC isolates were genotypically distinct from nonpathogenic E. coli and clustered independently. MANOVA analysis also revealed spatial variation among the E. coli isolates, since the majority of the isolates clustered according to the sampling locations. Although the presence of virulence genes alone cannot be used to determine the pathogenicity of strains, results from this study show that potentially pathogenic STEC and EPEC strains can be found in some of the avian hosts studied and may contaminate surface water and potentially impact human health. PMID:24441159

Pathogenic Potential, Genetic Diversity, and Population Structure of Escherichia coli Strains Isolated from a Forest-Dominated Watershed (Comox Lake) in British Columbia, Canada

PubMed Central

Mazumder, Asit

2014-01-01

Escherichia coli isolates (n = 658) obtained from drinking water intakes of Comox Lake (2011 to 2013) were screened for the following virulence genes (VGs): stx1 and stx2 (Shiga toxin-producing E. coli [STEC]), eae and the adherence factor (EAF) gene (enteropathogenic E. coli [EPEC]), heat-stable (ST) enterotoxin (variants STh and STp) and heat-labile enterotoxin (LT) genes (enterotoxigenic E. coli [ETEC]), and ipaH (enteroinvasive E. coli [EIEC]). The only genes detected were eae and stx2, which were carried by 37.69% (n = 248) of the isolates. Only eae was harbored by 26.74% (n = 176) of the isolates, representing potential atypical EPEC strains, while only stx2 was detected in 10.33% (n = 68) of the isolates, indicating potential STEC strains. Moreover, four isolates were positive for both the stx2 and eae genes, representing potential EHEC strains. The prevalence of VGs (eae or stx2) was significantly (P < 0.0001) higher in the fall season, and multiple genes (eae plus stx2) were detected only in fall. Repetitive element palindromic PCR (rep-PCR) fingerprint analysis of 658 E. coli isolates identified 335 unique fingerprints, with an overall Shannon diversity (H′) index of 3.653. Diversity varied among seasons over the years, with relatively higher diversity during fall. Multivariate analysis of variance (MANOVA) revealed that the majority of the fingerprints showed a tendency to cluster according to year, season, and month. Taken together, the results indicated that the diversity and population structure of E. coli fluctuate on a temporal scale, reflecting the presence of diverse host sources and their behavior over time in the watershed. Furthermore, the occurrence of potentially pathogenic E. coli strains in the drinking water intakes highlights the risk to human health associated with direct and indirect consumption of untreated surface water. PMID:25548059

Diversity of fecal coliforms and their antimicrobial resistance patterns in wastewater treatment model plant.

PubMed

Luczkiewicz, A; Fudala-Ksiazek, S; Jankowska, K; Quant, B; Olańczuk-Neyman, K

2010-01-01

The occurrence of resistance patterns among wastewater fecal coliforms was determined in the study. Susceptibility of the isolates was tested against 19 antimicrobial agents: aminoglycosides, aztreonam, carbapenems, cephalosporines, beta-lactam/beta-lactamase inhibitors, penicillines, tetracycline, trimethoprim/sulfamethoxazole, and fluoroquinolones. Additionally the removal of resistant isolates was evaluated in the laboratory-scale wastewater treatment model plant (M-WWTP), continuously supplied with the wastewater obtained from the full-scale WWTP. Number of fecal coliforms in raw (after mechanical treatment) and treated wastewater, as well as in aerobic chamber effluent was determined using selective medium. The selected strains were identified and examined for antibiotic resistance using Phoenix Automated Microbiology System (BD Biosciences, USA). The strains were identified as Escherichia coli (n=222), Klebsiella pneumoniae ssp. ozaenae (n=9), and Pantoea agglomerans (n=1). The isolate of P. agglomerans as well as 48% of E. coli isolates were sensitive to all antimicrobials tested. The most frequent resistance patterns were found for ampicillin: 100% of K. pneumoniae ssp. ozaenae and 41% of E. coli isolates. Among E. coli isolates 12% was regarded as multiple antimicrobial resistant (MAR). In the studied M-WWTP, the applied activated sludge processes reduced considerably the number of fecal coliforms, but increased the ratio of antimicrobial-resistant E. coli isolates to sensitive ones, especially among strains with MAR patterns.

The antimicrobial activity of probiotic bacteria Escherichia coli isolated from different natural sources against hemorrhagic E. coli O157:H7.

PubMed

Karimi, Sahar; Azizi, Fatemeh; Nayeb-Aghaee, Mohammad; Mahmoodnia, Leila

2018-03-01

Diarrheal diseases have been seen in all geographical areas throughout the world. Therefore, considering treatment, could be deemed a necessary action. The aim of this study was to determine the antimicrobial effect of probiotic bacterial strains isolated from different natural sources against 2 pathotypes of pathogenic E. coli. This cross-sectional study of Martyr Chamran University of Ahvaz was carried out from December 2013 to July 2014. A total of 13 probiotic colonies isolated from 20 samples of traditional dairy products including (yogurt, cheese, milk) and 20 samples of vegetables including carrots and cabbages (red and white) of which 5 isolates were selected to evaluate the antimicrobial effect against 2 Escherichia coli pathotypes, randomly. Antimicrobial effect was evaluated using two methods: disk diffusion and well diffusion tests and measuring growth inhibition zones of probiotics against 2 pathotypes of pathogenic E. coli. Obtained results showed growth inhibition effects of all 5 probiotic strains against Escherichia coli pathotypes in both used methods. All selected strains showed considerable antimicrobial effect on Escherichia coli O157:H7 strain, but had no inhibitory effect against Enterohemorrhagic Escherichia coli. This study demonstrated considerable antimicrobial effect against E. coli O157:H7 strain. Due to this, characteristic and similar antimicrobial effects of probiotics bacteria, increasing use of the probiotics as a natural and modern method for prevention of different diseases is recommended.

High genetic diversity among extraintestinal Escherichia coli isolates in pullets and layers revealed by a longitudinal study.

PubMed

Paudel, Surya; Stessl, Beatrix; Hess, Claudia; Zloch, Angelika; Hess, Michael

2016-10-07

Various information about the genetic diversity of Escherichia coli isolates from chickens are available but a detailed epidemiological investigation based upon isolates obtained from interrelated pullet and layer flocks is still missing. Therefore, in the course of a longitudinal epidemiological study on pullets and layers, 144 E. coli isolates from chickens with or without pathological lesions of the reproductive tract were serotyped and genotyped with pulsed-field gel electrophoresis (PFGE). These isolates were collected during rearing, peak and at the end of production. The actual study is the first of its kind so as to elucidate genetic relatedness among extraintestinal E. coli isolated from chickens with varying pathological conditions in interrelated layer farms/flocks at different stages of rearing. Serotyping revealed that 63.19 % of the isolates could not be assigned to any of the three serotypes tested whereas 30.55 % of the isolates belonged to serotype O1:K1, 4.86 % to O2:K1 and 1.38 % to O78:K80. After macrorestriction digest with XbaI, 91.66 % of the isolates were typeable resulting in 96 distinct PFGE profiles. Among them, five PFGE types included isolates collected from diseased chickens as well as from birds without pathological lesions. This finding shows that pathogenicity of E. coli in layers seems to be largely influenced by concurrent susceptibility factors. Furthermore, in six out of eight cases where two isolates were collected from each of eight birds, different PFGE types were found in the same or different organs of the same bird. The existence of predominant or persistent E. coli genotypes was only observed in two cases. It is concluded that extraintestinal E. coli genotypes and serotypes in pullets and layers are heterogenous and also do not maintain a single clonality within the same bird. The facts that E. coli strains did not show any definite clonal population structure based on geographical region, age of the host and pathological lesions should have relevance in further epidemiological studies and control strategies.

Determination of Sources of Escherichia coli on Beef by Multiple-Locus Variable-Number Tandem Repeat Analysis.

PubMed

Yang, Xianqin; Tran, Frances; Youssef, Mohamed K; Gill, Colin O

2015-07-01

The possible origin of Escherichia coli found on cuts and trimmings in the breaking facility of a beef packing plant was examined using multiple-locus variable-number tandem repeat analysis. Coliforms and E. coli were enumerated in samples obtained from 160 carcasses that would enter the breaking facility when work commenced and after each of the three production breaks throughout the day, from the conveyor belt before work and after each break, and from cuts and trimmings when work commenced and after each break. Most samples yielded no E. coli, irrespective of the surface types. E. coli was recovered from 7 (<5%) carcasses, at numbers mostly ≤1.0 log CFU/160,000 cm(2). The log total numbers of E. coli recovered from the conveyor belt, cuts, and trimmings were mostly between 1 and 2 log CFU/80,000 cm(2). A total of 554 E. coli isolates were recovered. Multiple-locus variable-number tandem repeat analysis of 327 selected isolates identified 80 distinct genotypes, with 37 (46%) each containing one isolate. However, 28% of the isolates were of genotypes that were recovered from more than one sampling day. Of the 80 genotypes, 65 and 2% were found in one or all four sampling periods throughout the day. However, they represented 23 and 14% of the isolates, respectively. Of the genotypes identified for each surface type, at least one contained ≥9 isolates. No unique genotypes were associated with carcasses, but 10, 17, and 19 were uniquely associated with cuts, trimmings, and the belt, respectively. Of the isolates recovered from cuts, 49, 3, and 19% were of genotypes that were found among isolates recovered from the belt, carcasses, or both the belt and carcasses, respectively. A similar composition was found for isolates recovered from trimmings. These findings show that the E. coli found on cuts and trimmings at this beef packing plant mainly originated from the conveyor belt and that small number of E. coli strains survived the daily cleaning and sanitation process, thus persisting in the plant.

Characterization of urinary tract infection-associated Shiga toxin-producing Escherichia coli.

PubMed

Toval, Francisco; Schiller, Roswitha; Meisen, Iris; Putze, Johannes; Kouzel, Ivan U; Zhang, Wenlan; Karch, Helge; Bielaszewska, Martina; Mormann, Michael; Müthing, Johannes; Dobrindt, Ulrich

2014-11-01

Enterohemorrhagic Escherichia coli (EHEC), a subgroup of Shiga toxin (Stx)-producing E. coli (STEC), is a leading cause of diarrhea and hemolytic-uremic syndrome (HUS) in humans. However, urinary tract infections (UTIs) caused by this microorganism but not associated with diarrhea have occasionally been reported. We geno- and phenotypically characterized three EHEC isolates obtained from the urine of hospitalized patients suffering from UTIs. These isolates carried typical EHEC virulence markers and belonged to HUS-associated E. coli (HUSEC) clones, but they lacked virulence markers typical of uropathogenic E. coli. One isolate exhibited a localized adherence (LA)-like pattern on T24 urinary bladder epithelial cells. Since the glycosphingolipids (GSLs) globotriaosylceramide (Gb3Cer) and globotetraosylceramide (Gb4Cer) are well-known receptors for Stx but also for P fimbriae, a major virulence factor of extraintestinal pathogenic E. coli (ExPEC), the expression of Gb3Cer and Gb4Cer by T24 cells and in murine urinary bladder tissue was examined by thin-layer chromatography and mass spectrometry. We provide data indicating that Stxs released by the EHEC isolates bind to Gb3Cer and Gb4Cer isolated from T24 cells, which were susceptible to Stx. All three EHEC isolates expressed stx genes upon growth in urine. Two strains were able to cause UTI in a murine infection model and could not be outcompeted in urine in vitro by typical uropathogenic E. coli isolates. Our results indicate that despite the lack of ExPEC virulence markers, EHEC variants may exhibit in certain suitable hosts, e.g., in hospital patients, a uropathogenic potential. The contribution of EHEC virulence factors to uropathogenesis remains to be further investigated. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Enterotoxigenic Escherichia coli infection in captive black-footed ferrets.

PubMed

Bradley, G A; Orr, K; Reggiardo, C; Glock, R D

2001-07-01

Enterotoxigenic Escherichia coli with genes for heat stabile toxins Sta and STb was isolated from the gastrointestinal tract and multiple visceral organs of three adult and three juvenile black-footed ferrets (Mustela nigripes) that died in a captive breeding colony between 24 May 1998 and 2 July 1998. Similar isolates were obtained from rectal swabs of one adult and one juvenile that were clinically ill. All were fed a diet composed of mink chow, raw rabbit meat, beef liver powder, blood meal and lard. Escherichia coli of the same toxin genotype was isolated from the mixed ration. Clinical signs included sudden death, dehydration, anorexia and diarrhea. Necropsy lesions included acute enteritis with large numbers of rod shaped bacteria microscopically visible on intestinal villi.

High prevalence of sequence type 131 isolates producing CTX-M-15 among ESBL-producing Escherichia coli strains in north-east Iran.

PubMed

Moghanni, Marzie; Ghazvini, Kiarash; Farsiani, Hadi; Namaei, Mohammad Hasan; Derakhshan, Mohammad; Yousefi, Masoud; Maragheh, Alimohammad; Jamehdar, Saeid Amel

2018-05-25

The recent expansion of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli (E. coli) is a worldwide problem. The purpose of this study was to investigate the molecular characteristic of ESBL-producing E. coli strains in Mashhad, located in the northeast of Iran. A total of 455 clinical isolates of E. coli were collected at three hospitals in Mashhad between April and September 2015. Antibiotic susceptibility was determined with the Kirby Bauer disk diffusion test. The Combination Disc Test (CDT) was performed for the phenotypic detection of ESBLs. PCR was used for screening isolates for ESBLs typing. Phylogenetic groups and sequence type 131 were determined by multiplex-PCR. The prevalence of ESBL-producing E. coli in the collected E. coli strains was 52% (235/455). Among the 235 ESBL producer strains, 94.4% (222/235) tested positive for the CTX-M type, while 115 (48.9%), 92 (39%) and 21 (8.9%) strains were positive for TEM, OXA and SHV, respectively. Moreover, CTX-M-15 (94.1%, 209/222) was the most common ESBL-producing E. coli. Based on multiplex-PCR, the phylogenetic group B2 was the most predominant (169 isolates, 71.9%), followed by D (32, 13.6%), A (21, 8.9%), and B1 (13, 5.5%). Of the 169 groups of B2 isolates, ST131 (151, 89.3%) was the predominant clonal group. The obtained results revealed that an urgent investigation of the source and the transmission pathways of the CTX-M15-B2ST131 E. coli clone was needed to countervail this emergent public health problem. Copyright © 2018. Published by Elsevier Ltd.

Phytochemical Screening and Antimicrobial Activity of Some Medicinal Plants Against Multi-drug Resistant Bacteria from Clinical Isolates

PubMed Central

Dahiya, Praveen; Purkayastha, Sharmishtha

2012-01-01

The in vitro antibacterial activity of various solvents and water extracts of aloe vera, neem, bryophyllum, lemongrass, tulsi, oregano, rosemary and thyme was assessed on 10 multi-drug resistant clinical isolates from both Gram-positive and Gram-negative bacteria and two standard strains including Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. The zone of inhibition as determined by agar well diffusion method varied with the plant extract, the solvent used for extraction, and the organism tested. Klebsiella pneumoniae 2, Escherichia coli 3 and Staphylococcus aureus 3 were resistant to the plant extracts tested. Moreover, water extracts did not restrain the growth of any tested bacteria. Ethanol and methanol extracts were found to be more potent being capable of exerting significant inhibitory activities against majority of the bacteria investigated. Staphylococcus aureus 1 was the most inhibited bacterial isolate with 24 extracts (60%) inhibiting its growth whereas Escherichia coli 2 exhibited strong resistance being inhibited by only 11 extracts (28%). The results obtained in the agar diffusion plates were in fair correlation with that obtained in the minimum inhibitory concentration tests. The minimum inhibitory concentration of tulsi, oregano, rosemary and aloe vera extracts was found in the range of 1.56-6.25 mg/ml for the multi-drug resistant Staphylococcus aureus isolates tested whereas higher values (6.25-25 mg/ml) were obtained against the multi-drug resistant isolates Klebsiella pneumoniae 1 and Escherichia coli 1 and 2. Qualitative phytochemical analysis demonstrated the presence of tannins and saponins in all plants tested. Thin layer chromatography and bioautography agar overlay assay of ethanol extracts of neem, tulsi and aloe vera indicated flavonoids and tannins as major active compounds against methicillin-resistant Staphylococcus aureus. PMID:23716873

Microbiological quality of water from the rivers of Curitiba, Paraná State, Brazil, and the susceptibility to antimicrobial drugs and pathogenicity of Escherichia coli.

PubMed

Giowanella, Melissa; Bozza, Angela; do Rocio Dalzoto, Patricia; Dionísio, Jair Alves; Andraus, Sumaia; Guimarães, Edson Luiz Gomes; Pimentel, Ida Chapaval

2015-11-01

Water safety is determined by several markers, and Escherichia coli is one of the most important indicators of water quality. The objective of this study was to evaluate the microbiological parameters in environmental samples of fresh water from rivers of Curitiba and its metropolitan area in Paraná State, Brazil. In addition, we evaluated the pathogenicity and susceptibility to antimicrobial drugs in E. coli. These evaluations were performed by quantitative and qualitative methods employing selective media for isolating thermotolerant coliforms and biochemical tests for identifying E. coli. Pathogenic strains of E. coli were detected by PCR multiplex using specific primers. From the water samples, 494 thermotolerant coliforms were obtained, of which 96 (19.43%) isolates were characterized as E. coli. Three isolates were identified as enteroaggregative E. coli, one as enterotoxigenic E. coli, one as enteropathogenic E. coli, and two carried the Eae virulence gene. E. coli susceptibility to commonly employed antimicrobial drugs was analyzed by the disc diffusion method. The results showed 49 (51.04%) isolates resistant to all the drugs assayed, 16 (16.67%) with an intermediate resistance to all drugs, and 31 (32.29%) intermediately or fully resistant to one or more drugs tested. The highest rate of resistance was observed for tetracycline 30 μg, streptomycin 10 μg, and ceftazidime 30 μg. Detection of E. coli is associated with water contamination by fecal material from humans and warm-blooded animals. The occurrence of resistant strains can be the result of the indiscriminate use of antimicrobial drugs and poor sanitation in the areas assayed.

Prevalence, antimicrobial resistance and virulence genes in Escherichia coli isolated from retail meats in Tamaulipas, México.

PubMed

Martínez-Vázquez, Ana Verónica; Rivera-Sánchez, Gildardo; Lira Méndez, Krystal; Reyes-López, Miguel Ángel; Bocanegra-García, Virgilio

2018-02-28

The aim of this work was to determinate the prevalence of Escherichia coli and its resistance to antimicrobials and the presence of virulence genes in retail samples of beef and pork in several locations in Tamaulipas. In this work, a total of 106 samples (beef and pork) collected from August 2013 to March 2014, were analyzed to detect Escherichia coli and then analyzed for virulence, antibiotic resistance gene detection, and tested for susceptibility to 16 antimicrobials. One hundred fifty-eight Escherichia coli isolates were obtained and of these, 1.8% harbored stx1; stx2 and hlyA was detected in 17.7% and 21.5% of isolates, respectively. High-resistance phenotypes were observed in almost all of the isolates since 92.4% showed a multi-resistant phenotype with resistance to cephalothin 92%, ampicillin 92%, cefotaxime 78%, nitrofurantoin 76% and tetracycline 75%. tetA and tetB were detected in 56% of isolates, strA in 9.6%, aadA in 17%, and aac(3)-IV in only 0.6% of strains. Based on these results, it can be concluded that retail beef and pork meat, might play a role in the spread of antibiotic resistant Escherichia coli strains in our region. Copyright © 2018. Published by Elsevier Ltd.

Clonal group distribution of fluoroquinolone-resistant Escherichia coli among humans and companion animals in Australia.

PubMed

Platell, Joanne L; Cobbold, Rowland N; Johnson, James R; Trott, Darren J

2010-09-01

To determine the phylogenetic group distribution and prevalence of three major globally disseminated clonal groups [clonal group A (CGA) and O15:K52:H1, associated with phylogenetic group D, and sequence type ST131, associated with phylogenetic group B2] among fluoroquinolone-resistant extra-intestinal Escherichia coli isolates from humans and companion animals in Australia. Clinical extra-intestinal fluoroquinolone-resistant E. coli isolates were obtained from humans (n = 582) and companion animals (n = 125), on Australia's east coast (October 2007-October 2009). Isolates were tested for susceptibility to seven antimicrobial agents, and for phylogenetic group, O type and clonal-group-specific single nucleotide polymorphisms by PCR. The fluoroquinolone-resistant isolates were typically resistant to multiple agents (median of four). Analysis revealed that clonal group ST131 accounted for a large subset of the human isolates (202/585, 35%), but for a much smaller proportion of the companion animal isolates (9/125, 7.2%; P

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa.

PubMed

Malema, Mokaba Shirley; Abia, Akebe Luther King; Tandlich, Roman; Zuma, Bonga; Mwenge Kahinda, Jean-Marc; Ubomba-Jaswa, Eunice

2018-05-01

Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert ® 18/Quanti-Tray ® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) ( ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli.

Antibiotic-Resistant Pathogenic Escherichia Coli Isolated from Rooftop Rainwater-Harvesting Tanks in the Eastern Cape, South Africa

PubMed Central

Malema, Mokaba Shirley; Tandlich, Roman; Zuma, Bonga; Mwenge Kahinda, Jean-Marc

2018-01-01

Although many developing countries use harvested rainwater (HRW) for drinking and other household purposes, its quality is seldom monitored. Continuous assessment of the microbial quality of HRW would ensure the safety of users of such water. The current study investigated the prevalence of pathogenic Escherichia coli strains and their antimicrobial resistance patterns in HRW tanks in the Eastern Cape, South Africa. Rainwater samples were collected weekly between June and September 2016 from 11 tanks in various areas of the province. Enumeration of E. coli was performed using the Colilert®18/Quanti-Tray® 2000 method. E. coli isolates were obtained and screened for their virulence potentials using polymerase chain reaction (PCR), and subsequently tested for antibiotic resistance using the disc-diffusion method against 11 antibiotics. The pathotype most detected was the neonatal meningitis E. coli (NMEC) (ibeA 28%) while pathotype enteroaggregative E. coli (EAEC) was not detected. The highest resistance of the E. coli isolates was observed against Cephalothin (76%). All tested pathotypes were susceptible to Gentamicin, and 52% demonstrated multiple-antibiotic resistance (MAR). The results of the current study are of public health concern since the use of untreated harvested rainwater for potable purposes may pose a risk of transmission of pathogenic and antimicrobial-resistant E. coli. PMID:29723970

The occurrence of ESBL-producing Escherichia coli carrying aminoglycoside resistance genes in urinary tract infections in Saudi Arabia.

PubMed

Alyamani, Essam J; Khiyami, Anamil M; Booq, Rayan Y; Majrashi, Majed A; Bahwerth, Fayez S; Rechkina, Elena

2017-01-06

The infection and prevalence of extended-spectrum β-lactamases (ESBLs) is a worldwide problem, and the presence of ESBLs varies between countries. In this study, we investigated the occurrence of plasmid-mediated ESBL/AmpC/carbapenemase/aminoglycoside resistance gene expression in Escherichia coli using phenotypic and genotypic techniques. A total of 58 E. coli isolates were collected from hospitals in the city of Makkah and screened for the production of ESBL/AmpC/carbapenemase/aminoglycoside resistance genes. All samples were subjected to phenotypic and genotypic analyses. The antibiotic susceptibility of the E. coli isolates was determined using the Vitek-2 system and the minimum inhibitory concentration (MIC) assay. Antimicrobial agents tested using the Vitek 2 system and MIC assay included the expanded-spectrum (or third-generation) cephalosporins (e.g., cefoxitin, cefepime, aztreonam, cefotaxime, ceftriaxone, and ceftazidime) and carbapenems (meropenem and imipenem). Reported positive isolates were investigated using genotyping technology (oligonucleotide microarray-based assay and PCR). The genotyping investigation was focused on ESBL variants and the AmpC, carbapenemase and aminoglycoside resistance genes. E. coli was phylogenetically grouped, and the clonality of the isolates was studied using multilocus sequence typing (MLST). Our E. coli isolates exhibited different levels of resistance to ESBL drugs, including ampicillin (96.61%), cefoxitin (15.25%), ciprofloxacin (79.66%), cefepime (75.58%), aztreonam (89.83%), cefotaxime (76.27%), ceftazidime (81.36%), meropenem (0%) and imipenem (0%). Furthermore, the distribution of ESBL-producing E. coli was consistent with the data obtained using an oligonucleotide microarray-based assay and PCR genotyping against genes associated with β-lactam resistance. ST131 was the dominant sequence type lineage of the isolates and was the most uropathogenic E. coli lineage. The E. coli isolates also carried aminoglycoside resistance genes. The evolution and prevalence of ESBL-producing E. coli may be rapidly accelerating in Saudi Arabia due to the high visitation seasons (especially to the city of Makkah). The health authority in Saudi Arabia should monitor the level of drug resistance in all general hospitals to reduce the increasing trend of microbial drug resistance and the impact on patient therapy.

Characterization of Escherichia coli populations from gulls, landfill trash, and wastewater using ribotyping.

PubMed

Nelson, M; Jones, S H; Edwards, C; Ellis, J C

2008-08-19

Due to their opportunistic and gregarious nature, gulls may be important reservoirs and vectors for anthropogenically derived fecal pathogens in coastal areas. We used ribotyping, a genotypic bacterial source tracking method, to compare populations of Escherichia coli among herring gulls Larus argentatus, great black-backed gulls L. marinus, wastewater, and landfill trash in New Hampshire and Maine, USA. Concentrations of E. coli in gull feces varied widely among individuals, but were generally high (6.0 x 10(1) to 2.5 x 10(9) g(-1) wet weight). Of 39 E. coli isolates from L. argentatus, 67% had banding patterns that were > or = 90% similar to those from wastewater and trash, whereas only 39% of 36 L. marinus isolates exhibited > or = 90% similarity to these sources. Strains of E. coli from gulls matched (> or = 90% similarity) more strains from wastewater (39% matching) than from trash (15% matching). E. coli isolates from L. marinus feces exhibited a greater diversity of banding patterns than did isolates from L. argentatus. There were more unique E. coli banding patterns in trash samples than in wastewater, and higher diversity indices in the former compared to the latter. These findings suggest that both species of gulls, especially L. argentatus, obtain fecal bacteria from wastewater and landfill trash, which they may transport to recreational beaches and waters. Our results also indicate that E. coli populations may vary widely between gull species, and between the anthropogenic habitats that they frequent, i.e. landfills and wastewater treatment facilities.

Dissemination and genetic support of broad-spectrum beta-lactam-resistant Escherichia coli strain isolated from two Tunisian hospitals during 2004-2012.

PubMed

Ayari, Khaoula; Bourouis, Amel; Chihi, Hela; Mahrouki, Sihem; Naas, Thierry; Belhadj, Omrane

2017-06-01

The dissemination of extended-spectrum β-lactamase (ESBL)-producing bacteria presented a great concern worldwide. Gram-negative organisms such as Escherichia coli and Klebsiella pneumoniae are the most frequently isolated pathogens responsible for nosocomial infections. The aim of this study was to investigate and to follow the emergence of resistance and the characterization of Extended-Spectrum Beta-Lactamases (ESBL) among broad-spectrum beta-lactam- Escherichia coli clinical isolates recovered from the military hospital and Habib Thameur hospital in Tunisia. A total of 113 E.coli isolates obtained during the period 2004 through 2012 showed a significant degree of multi-resistance. Among these strains, the double-disk synergy test confirmed the ESBL phenotype in 46 isolates. These included 32(70%) strains from Hospital A and 14(30%) from Hospital B. The ESBL was identified as CTX-M-15. The ESBL resistance was transferred by a 60 kb plasmid CTXM-15-producing isolates were unrelated according to the PFGE analysis and characterization of the regions surrounding the blaCTX-M-15 showed the ISEcp1 elements located in the upstream region of the bla gene and 20 of them truncated by IS26. ESBL producing E. coli strains are a serious threat in the community in Tunisia and we should take into consideration any possible spread of such epidemiological resistance.

Identification of Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa in Blood Cultures: a Multicenter Performance Evaluation of a Three-Color Peptide Nucleic Acid Fluorescence In Situ Hybridization Assay▿

PubMed Central

Della-Latta, Phyllis; Salimnia, Hossein; Painter, Theresa; Wu, Fann; Procop, Gary W.; Wilson, Deborah A.; Gillespie, Wendy; Mender, Alayna; Crystal, Benjamin S.

2011-01-01

A multicenter evaluation was undertaken to evaluate the performance of a new three-color peptide nucleic acid fluorescence in situ hybridization assay that identifies isolates directly from blood cultures positive for Gram-negative bacilli (GNB). The assay correctly identified 100% (186/186) of the Escherichia coli isolates, 99.1% (109/110) of the Klebsiella pneumoniae isolates, and 95.8% (46/48) of the Pseudomonas aeruginosa isolates in this study. Negative assay results were correctly obtained for 162 of 165 other GNB (specificity, 98.2%). PMID:21490185

Extended-spectrum β-lactamases, transferable quinolone resistance, and virulotyping in extra-intestinal E. coli in Uruguay.

PubMed

Vignoli, Rafael; García-Fulgueiras, Virginia; Cordeiro, Nicolás F; Bado, Inés; Seija, Verónica; Aguerrebere, Paula; Laguna, Gabriel; Araújo, Lucía; Bazet, Cristina; Gutkind, Gabriel; Chabalgoity, José

2016-01-31

To characterize extended-spectrum β-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR) genes in Escherichia coli isolates obtained from extra-intestinal samples in three Uruguayan hospitals. Fifty-five ESBL-producing E. coli isolates were studied. Virulence genes, ESBLs, and PMQR genes were detected by polymerase chain reaction. ESBL-producing isolates were compared by pulsed-field gel electrophoresis. Multi-locus sequence typing was also performed on 13 selected isolates. Thirty-seven isolates harbored blaCTX-M-15 (67.3%), eight blaCTX-M-2 (14.6%), five blaCTX-M-14 (9.1%), three carried both blaCTX-M-2 and blaCTX-M-14, one blaCTX-M-9, and one blaCTX-M-8. Among the CTX-M-15 producers, 92% belonged to sequence types ST131 and ST405, and carried aac(6')Ib-cr as well. Isolates harboring blaCTX-M-2, blaCTX-M-14, blaCTX-M-9, or blaCTX-M-8 were found to be genetically unrelated. The successful dissemination of CTX-M-15-producing E.coli isolates seems to be linked to the spreading of high-risk clones and horizontal gene transfer. A trade-off between carrying more antibiotic resistance and less virulence-related genes could partially account for the evolutionary advantages featured by successful clones.

Geographic isolation of Escherichia coli genotypes in sediments and water of the Seven Mile Creek - A constructed riverine watershed.

PubMed

Chandrasekaran, Ramyavardhanee; Hamilton, Matthew J; Wang, Ping; Staley, Christopher; Matteson, Scott; Birr, Adam; Sadowsky, Michael J

2015-12-15

Escherichia coli is used to indicate fecal contamination in freshwater systems and is an indicator of the potential presence of human pathogens. However, naturalized E. coli strains that persist and grow in the environment confound the use of this bacterium as a fecal indicator. Here we examined the spatial and temporal distribution of E. coli in water and sediments of the Seven Mile Creek (SMC), a constructed, ephemeral watershed. E. coli concentrations showed variation by site and date, likely due to changes in temperature and rainfall. Horizontal fluorophore enhanced rep-PCR (HFERP) DNA fingerprint analyses indicated that E. coli populations were very diverse and consisted of transient and naturalized strains, which were especially prevalent in sediment. E. coli fingerprints from water and sediment collected in the same year clustered together with significant overlap, indicating exchange of strains between matrices. Isolates obtained during periods of flow, but not during non-flow conditions, clustered together regardless of sample site, indicating that transport between sites occurred. Naturalized E. coli strains were found in the SMC and strains become geographically isolated and distinct during non-flow conditions. Isolates collected during late spring to fall clustered together at each site, suggesting that temperature and growth of naturalized strains are likely factors affecting population dynamics. Results of this study show that newly introduced and naturalized E. coli strains are present in the SMC. Results of this study highlight an important concern for resource managers using this species for water quality monitoring. Copyright © 2015 Elsevier B.V. All rights reserved.

In silico serotyping of E. coli from short read data identifies limited novel O-loci but extensive diversity of O:H serotype combinations within and between pathogenic lineages.

PubMed

Ingle, Danielle J; Valcanis, Mary; Kuzevski, Alex; Tauschek, Marija; Inouye, Michael; Stinear, Tim; Levine, Myron M; Robins-Browne, Roy M; Holt, Kathryn E

2016-07-01

The lipopolysaccharide (O) and flagellar (H) surface antigens of Escherichia coli are targets for serotyping that have traditionally been used to identify pathogenic lineages. These surface antigens are important for the survival of E. coli within mammalian hosts. However, traditional serotyping has several limitations, and public health reference laboratories are increasingly moving towards whole genome sequencing (WGS) to characterize bacterial isolates. Here we present a method to rapidly and accurately serotype E. coli isolates from raw, short read WGS data. Our approach bypasses the need for de novo genome assembly by directly screening WGS reads against a curated database of alleles linked to known and novel E. coli O-groups and H-types (the EcOH database) using the software package srst2. We validated the approach by comparing in silico results for 197 enteropathogenic E. coli isolates with those obtained by serological phenotyping in an independent laboratory. We then demonstrated the utility of our method to characterize isolates in public health and clinical settings, and to explore the genetic diversity of >1500 E. coli genomes from multiple sources. Importantly, we showed that transfer of O- and H-antigen loci between E. coli chromosomal backbones is common, with little evidence of constraints by host or pathotype, suggesting that E. coli ' strain space' may be virtually unlimited, even within specific pathotypes. Our findings show that serotyping is most useful when used in combination with strain genotyping to characterize microevolution events within an inferred population structure.

Antimicrobial and disinfectant resistance of Escherichia coli isolated from giant pandas.

PubMed

Guo, L; Long, M; Huang, Y; Wu, G; Deng, W; Yang, X; Li, B; Meng, Y; Cheng, L; Fan, L; Zhang, H; Zou, L

2015-07-01

The study aims to demonstrate the antimicrobial and disinfectant resistance phenotypes and genotypes of Escherichia coli isolates obtained from giant pandas (Ailuropoda melanoleuca). Antimicrobial testing was performed according to the standard disk diffusion method. The minimal inhibitory concentrations (MICs) of disinfectants were determined using the agar dilution method. All isolates were screened for the presence of antimicrobial and disinfectant resistance genes and further analysed for genetic relatedness by pulse-field gel electrophoresis (PFGE). Results showed that 46·6% of the isolates were resistant to at least one antimicrobial. Escherichia coli isolates showed resistance to fewer antimicrobials as panda age increased. Among antimicrobial-resistant E. coli isolates, the antimicrobial resistance genes blaCTX-M (88·2%) and sul1 (92·3%) were most prevalent. The disinfectant resistance genes emrE, ydgE/ydgF, mdfA and sugE(c) were commonly present (68·2-98·9%), whereas qac and sugE(p) were relatively less prevalent (0-21·3%). The frequencies of resistance genes tended to be higher in E. coli isolated in December than in July, and PFGE profiles were also more diverse in isolates in December. The qacEΔ1 and sugE(p) genes were higher in adolescent pandas than in any other age groups. PFGE revealed that antimicrobial resistance correlated well with sampling time and habitat. This study demonstrated that antimicrobial and disinfectant resistance was common in giant panda-derived E. coli, and the antimicrobial resistance was associated with sampling time and habitat. Escherichia coli could serve as a critical vector in spreading disinfectant and antimicrobial resistance. This is the first study that demonstrated the phenotypic and genetic characterizations of antimicrobial and disinfectant resistance in E. coli isolates from more than 60 giant pandas. Frequent transfer of pandas to other cages may lead to the dissemination of antimicrobial resistance. The study highlights the need for regularly monitoring the antimicrobial and disinfectant resistance in bacteria from giant pandas. © 2015 The Society for Applied Microbiology.

Prevalence of virulence determinants and antimicrobial resistance among commensal Escherichia coli derived from dairy and beef cattle.

PubMed

Bok, Ewa; Mazurek, Justyna; Stosik, Michał; Wojciech, Magdalena; Baldy-Chudzik, Katarzyna

2015-01-19

Cattle is a reservoir of potentially pathogenic E. coli, bacteria that can represent a significant threat to public health, hence it is crucial to monitor the prevalence of the genetic determinants of virulence and antimicrobial resistance among the E. coli population. The aim of this study was the analysis of the phylogenetic structure, distribution of virulence factors (VFs) and prevalence of antimicrobial resistance among E. coli isolated from two groups of healthy cattle: 50 cows housed in the conventional barn (147 isolates) and 42 cows living on the ecological pasture (118 isolates). The phylogenetic analysis, identification of VFs and antimicrobial resistance genes were based on either multiplex or simplex PCR. The antimicrobial susceptibilities of E. coli were examined using the broth microdilution method. Two statistical approaches were used to analyse the results obtained for two groups of cattle. The relations between the dependent (VFs profiles, antibiotics) and the independent variables were described using the two models. The mixed logit model was used to characterise the prevalence of the analysed factors in the sets of isolates. The univariate logistic regression model was used to characterise the prevalence of these factors in particular animals. Given each model, the odds ratio (OR) and the 95% confidence interval for the population were estimated. The phylogroup B1 was predominant among isolates from beef cattle, while the phylogroups A, B1 and D occurred with equal frequency among isolates from dairy cattle. The frequency of VFs-positive isolates was significantly higher among isolates from beef cattle. E. coli from dairy cattle revealed significantly higher resistance to antibiotics. Some of the tested resistance genes were present among isolates from dairy cattle. Our study showed that the habitat and diet may affect the genetic diversity of commensal E. coli in the cattle. The results suggest that the ecological pasture habitat is related to the increased spreading rate of the VFs, while the barn habitat is characterised by the higher levels of antimicrobial resistance among E. coli.

Prevalence of Virulence Determinants and Antimicrobial Resistance among Commensal Escherichia coli Derived from Dairy and Beef Cattle

PubMed Central

Bok, Ewa; Mazurek, Justyna; Stosik, Michał; Wojciech, Magdalena; Baldy-Chudzik, Katarzyna

2015-01-01

Cattle is a reservoir of potentially pathogenic E. coli, bacteria that can represent a significant threat to public health, hence it is crucial to monitor the prevalence of the genetic determinants of virulence and antimicrobial resistance among the E. coli population. The aim of this study was the analysis of the phylogenetic structure, distribution of virulence factors (VFs) and prevalence of antimicrobial resistance among E. coli isolated from two groups of healthy cattle: 50 cows housed in the conventional barn (147 isolates) and 42 cows living on the ecological pasture (118 isolates). The phylogenetic analysis, identification of VFs and antimicrobial resistance genes were based on either multiplex or simplex PCR. The antimicrobial susceptibilities of E. coli were examined using the broth microdilution method. Two statistical approaches were used to analyse the results obtained for two groups of cattle. The relations between the dependent (VFs profiles, antibiotics) and the independent variables were described using the two models. The mixed logit model was used to characterise the prevalence of the analysed factors in the sets of isolates. The univariate logistic regression model was used to characterise the prevalence of these factors in particular animals. Given each model, the odds ratio (OR) and the 95% confidence interval for the population were estimated. The phylogroup B1 was predominant among isolates from beef cattle, while the phylogroups A, B1 and D occurred with equal frequency among isolates from dairy cattle. The frequency of VFs-positive isolates was significantly higher among isolates from beef cattle. E. coli from dairy cattle revealed significantly higher resistance to antibiotics. Some of the tested resistance genes were present among isolates from dairy cattle. Our study showed that the habitat and diet may affect the genetic diversity of commensal E. coli in the cattle. The results suggest that the ecological pasture habitat is related to the increased spreading rate of the VFs, while the barn habitat is characterised by the higher levels of antimicrobial resistance among E. coli. PMID:25607605

Extended spectrum β-lactamase and plasmid mediated quinolone resistance in Escherichia coli fecal isolates from healthy companion animals in Algeria.

PubMed

Yousfi, Massilia; Mairi, Assia; Touati, Abdelaziz; Hassissene, Lila; Brasme, Lucien; Guillard, Thomas; De Champs, Christophe

2016-07-01

The aim of this study was to evaluate the rate of fecal carriage of Escherichia coli strains producing Extended-spectrum β-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR) isolated from healthy pets (dogs and cats) in Algeria. Fecal samples from 171 healthy pets (102 dogs and 69 cats) in one veterinary practice and private owners were included. After isolates identification, antibiotic susceptibility was determined by disk diffusion procedure. ESBL were detected by combination disk tests. PCR and sequencing were used to characterize genes encoding ESBLs and PMQR. Transfer of ESBL and PMQR genes was assessed by conjugation experiments. Phylogenetic groups of E. coli were determined by PCR. Of the 171 animals, 20 carried an ESBL producing E. coli giving a prevalence of ESBL fecal carriage of 11.7%. All isolates were susceptible to carbapenems, cefoxitin, piperacillin-tazobactam, amikacin and fosfomycine. For the rest of the tested β-lactams, susceptibility rates ranged from 35% to 70% for cefepime and amoxicillin-clavulanic acid respectively. Concerning the non-beta-lactams antibiotics, the rates of susceptibility ranged between 5% to trimethoprim and 95% for chloramphenicol. The beta-lactamase genes identified in E. coli isolates were blaCTX-M-15, blaCTX-M-1, blaSHV-12 and blaTEM-1. The PMQR determinants aac(6')-Ib-cr, qnrS1 and qnrB5 genes were identified in 15 isolates. Transconjugants were obtained for two isolates. Phylogenetic analysis showed that E. coli isolates belong to commensal phylogroups of A and B1. We reported here for the first time in Algeria ESBL and PMQR-producing E. coli in healthy cats and dogs. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Multiple antibiotic resistant Escherichia coli from a tropical rain forest stream

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carrasco, C.E.; Alvarez, H.J.; Ortiz, N.

1988-12-31

High densities of fecal coliforms were obtained from a pristine site and sewage contaminated site in a tropical rain forest watershed in Puerto Rico. Confirmation of fecal coliform isolates as Escherichia coli was significantly lower than for temperate waters. Antibiotic resistance and multiple antibiotic resistance were common for isolates at both sites; however, the site receiving sewage effluent had a greater proportion of multiple antibiotic resistant isolates. R. plasmids were recovered from 4 MAR isolates, 2 from each site. All recovered plasmids were approximately 1 kilobase. The recovered plasmid were also capable of transforming E. coli HB101 in vitro. Themore » high concentrations of enterobacteriaceae, small R-plasmid size, R-plasmid transformability, and long term survival of fecal origin bacteria in tropical freshwater environments give increasing importance to adequate sewage treatment, and better indicator monitoring methods for tropical areas.« less

Patterns of Antimicrobial Resistance Observed in Escherichia coli Isolates Obtained from Domestic- and Wild-Animal Fecal Samples, Human Septage, and Surface Water

PubMed Central

Sayah, Raida S.; Kaneene, John B.; Johnson, Yvette; Miller, RoseAnn

2005-01-01

A repeated cross-sectional study was conducted to determine the patterns of antimicrobial resistance in 1,286 Escherichia coli strains isolated from human septage, wildlife, domestic animals, farm environments, and surface water in the Red Cedar watershed in Michigan. Isolation and identification of E. coli were done by using enrichment media, selective media, and biochemical tests. Antimicrobial susceptibility testing by the disk diffusion method was conducted for neomycin, gentamicin, streptomycin, chloramphenicol, ofloxacin, trimethoprim-sulfamethoxazole, tetracycline, ampicillin, nalidixic acid, nitrofurantoin, cephalothin, and sulfisoxazole. Resistance to at least one antimicrobial agent was demonstrated in isolates from livestock, companion animals, human septage, wildlife, and surface water. In general, E. coli isolates from domestic species showed resistance to the largest number of antimicrobial agents compared to isolates from human septage, wildlife, and surface water. The agents to which resistance was demonstrated most frequently were tetracycline, cephalothin, sulfisoxazole, and streptomycin. There were similarities in the patterns of resistance in fecal samples and farm environment samples by animal, and the levels of cephalothin-resistant isolates were higher in farm environment samples than in fecal samples. Multidrug resistance was seen in a variety of sources, and the highest levels of multidrug-resistant E. coli were observed for swine fecal samples. The fact that water sample isolates were resistant only to cephalothin may suggest that the resistance patterns for farm environment samples may be more representative of the risk of contamination of surface waters with antimicrobial agent-resistant bacteria. PMID:15746342

Phylo-typing of clinical Escherichia coli isolates originating from bovine mastitis and canine pyometra and urinary tract infection by means of quadruplex PCR.

PubMed

Müştak, Hamit Kaan; Günaydin, Elçin; Kaya, İnci Başak; Salar, Merve Özdal; Babacan, Orkun; Önat, Kaan; Ata, Zafer; Diker, Kadir Serdar

2015-01-01

Escherichia coli is one of the major causative agents of bovine mastitis worldwide, and is typically associated with acute, clinical mastitis. Besides this, E. coli strains which belong to the extra-intestinal pathogenic group are also the major cause of urinary tract infections and pyometra in dogs. In this study, it was aimed to investigate phylo-groups/subgroups in 155 E. coli isolates obtained from acute bovine mastitis, 43 from urinary tract infections of dogs and 20 from canine pyometra by a formerly described triplex PCR and recently described new quadruplex polymerase chain reaction (PCR) method. Group A1 (n = 118; 76%) and B1 (n = 71; 46%) were found to be the most prevalent groups by triplex and quadruplex PCR assays in mastitis isolates, respectively. Phylo-typing of 43 urinary tract isolates also revealed that most of the isolates belonged to A1 (n = 23; 54%) by triplex and B2 (n = 36; 84%) by quadruplex PCR assays. The isolates assigned as group A1 (n = 17; 85%) by triplex PCR could not be classified by quadruplex PCR in pyometra isolates. The results support the hypothesis that E. coli strains isolated from bovine mastitis cases are environmental. Also, groups C, E and F were identified as new phylo-groups for the first time in acute bovine mastitis cases. The comparison of triplex PCR with quadruplex PCR results revealed that most of the groups assigned in triplex PCR were altered by quadruplex PCR assay.

[Study on national active monitoring for food borne pathogens and antimicrobial resistance in China 2001].

PubMed

Wang, Maoqi; Ran, Lu; Wang, Zhutian; Li, Zhigang

2004-01-01

To survey food borne pathogens and antimicrobial resistance in China. A total of 4034 samples of foods (raw meats, raw milk, cooked meats, ice cream, yoghurt, aquatic product and vegetable) were examined for the presence of Escherichia coli O157:H7 Salmonella spp and Listeria monocytogens by national active foodborne pathogens surveillance system. The samples were obtained from 11 provinces in 2001. Approximate 5.50% of the all samples yielded 3 pathogenes, whereas Escherichia coli O157:H7 (0.82%), Salmonella servoars (3.32%) and Listeria monocytogens (1.29%). The most heavy contamination by three food borne pathogens are in raw meat (12.96%). Top seven serotype of the 137 Salmonella isolates are S. derby, S. agona, S. enteritidis, S. reading, S. anatum. S. muenster, S. typhimurium. Serotypes and antibiotic resistance patterns of Salmonella isolates are different in 11 provinces. E. coli O157:H7 strains that are isolated from raw meat and cooked meat have VT2, eae, Hly genes. Salmonella and E. coli strains of multidrug resistance were isolated and identified.

Laboratory investigation of a multistate food-borne outbreak of Escherichia coli O157:H7 by using pulsed-field gel electrophoresis and phage typing.

PubMed Central

Barrett, T J; Lior, H; Green, J H; Khakhria, R; Wells, J G; Bell, B P; Greene, K D; Lewis, J; Griffin, P M

1994-01-01

Two hundred thirty-three isolates of Escherichia coli O157:H7 were analyzed by both pulsed-field gel electrophoresis (PFGE) and bacteriophage typing. All 26 isolates from persons whose illness was associated with a recent multistate outbreak of E. coli O157:H7 infections linked to the consumption of undercooked hamburgers and all 27 isolates from incriminated lots of hamburger meat had the same phage type and the same PFGE pattern. Twenty-five of 74 E. coli O157:H7 isolates from Washington State and 10 of 27 isolates from other states obtained during the 6 months before the outbreak had the same phage type as the outbreak strain, but only 1 isolate had the same PFGE pattern. PFGE thus appeared to be a more sensitive method than bacteriophage typing for distinguishing outbreak and non-outbreak-related strains. The PFGE patterns of seven preoutbreak sporadic isolates and five sporadic isolates from the outbreak period differed from that of the outbreak strain by a single band, making it difficult to identify these isolates as outbreak or non-outbreak related. Phage typing and PFGE with additional enzymes were helpful in resolving this problem. While not as sensitive as PFGE, phage typing was helpful in interpreting PFGE data and could have been used as a simple, rapid screen to eliminate the need for performing PFGE on unrelated isolates. Images PMID:7883892

Identification and differentiation of Campylobacter species by high-resolution melting curve analysis.

PubMed

Hoseinpour, Fatemeh; Foroughi, Azadeh; Nomanpour, Bizhan; Nasab, Rezvan Sobhani

2017-07-01

Campylobacter jejuni and Campylobacter coli are the important food-born zoonotic pathogen, also are leading causes of human food borne illnesses worldwide. cadF gene is expressed in all C. jejuni and C. coli strains and mediates cell binding to the cell matrix protein, Fibronectin. High-resolution melting (HRM) analysis is emerging as an efficient and robust method for discriminating DNA sequence variants. The goal of this study was to apply HRM analysis to identification of C. jejuni and C. coli. A total of 100 samples were obtained from chicken in Kermanshah, Iran. HRM analysis based on cadF gene and Eva Green was developed to the identification of Campylobacter to the species level. Fifty-five of 100 samples were positive as campylobacter (7 C. jejuni, 29 C. coli, 16 mixes and 3 unknown). Minor variations were observed in melting point temperatures of C. coli or C. jejuni isolates and this variation can be used to the differentiation between C. coli or C. jejuni isolates. The results of this study indicated that HRM curve analysis can be a suitable technique and rapid technique for distinguishing between C. jejuni and C. coli isolates. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Survey for Escherichia coli Virulence Factors in Asymptomatic Free-Ranging Parrots

PubMed Central

Becker Saidenberg, André; Robaldo Guedes, Neiva Maria; Fernandes Seixas, Gláucia Helena; da Costa Allgayer, Mariangela; Pacífico de Assis, Erica; Fabio Silveira, Luis; Anne Melville, Priscilla; Benites, Nilson Roberti

2012-01-01

Parrots in captivity are frequently affected by Escherichia coli (E. coli) infections. The objective of this study was to collect information on the carrier state for E. coli pathotypes in asymptomatic free-ranging parrots. Cloacal swabs were collected from nestlings of Hyacinth, Lear's macaws and Blue-fronted Amazon parrots and tested by polymerase chain reaction (PCR) for virulence factors commonly found in enteropathogenic, avian pathogenic, and uropathogenic E. coli strains. In total, 44 samples were cultured and E. coli isolates were yielded, from which DNA was extracted and processed by PCR. Genes commonly found in APEC isolates from Blue-fronted Amazon parrots and Hyacinth macaws were expressed in 14 of these 44 samples. One atypical EPEC isolate was obtained from a sample from Lear's macaw. The most commonly found gene was the increased serum survival (iss) gene. This is the first report, that describes such pathotypes in asymptomatic free-living parrots. The findings of this study suggest the presence of a stable host/parasite relationship at the time of the sampling brings a new understanding to the role that E. coli plays in captive and wild parrots. Such information can be used to improve husbandry protocols as well as help conservation efforts of free-living populations. PMID:23738135

Prevalence and Genomic Characterization of Escherichia coli O157:H7 in Cow-Calf Herds throughout California.

PubMed

Worley, Jay N; Flores, Kristopher A; Yang, Xun; Chase, Jennifer A; Cao, Guojie; Tang, Shuai; Meng, Jianghong; Atwill, Edward R

2017-08-15

Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms. IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations. Copyright © 2017 American Society for Microbiology.

Prevalence and Genomic Characterization of Escherichia coli O157:H7 in Cow-Calf Herds throughout California

PubMed Central

Worley, Jay N.; Flores, Kristopher A.; Yang, Xun; Chase, Jennifer A.; Cao, Guojie; Tang, Shuai; Meng, Jianghong

2017-01-01

ABSTRACT Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. California is one of the most agriculturally productive regions in the world for fresh produce, beef, and milk. The close proximity of fresh produce and cattle presents food safety challenges on a uniquely large scale. We performed a survey of E. coli O157:H7 on 20 farms in California to observe the regional diversity and prevalence of E. coli O157:H7. Isolates were obtained from enrichment cultures of cow feces. Some farms were sampled on two dates. Genomes from isolates were sequenced to determine their relatedness and pathogenic potential. E. coli O157:H7 was isolated from approximately half of the farms. The point prevalence of E. coli O157:H7 on farms was highly variable, ranging from zero to nearly 90%. Within farms, generally one or a few lineages were found, even when the rate of isolation was high. On farms with high isolation rates, a single clonal lineage accounted for most of the isolates. Farms that were visited months after the first visit might have had the same lineages of E. coli O157:H7. Strains of E. coli O157:H7 may be persistent for months on farms. IMPORTANCE This survey of 20 cow-calf operations from different regions of California provides an in depth look at resident Escherichia coli O157:H7 populations at the molecular level. E. coli O157:H7 is found to have a highly variable prevalence, and with whole-genome sequencing, high prevalences in herds were found to be due to a single lineage shed from multiple cows. Few repeat lineages were found between farms in this area; therefore, we predict that E. coli O157:H7 has significant diversity in this area beyond what is detected in this survey. All isolates from this study were found to have pathogenic potential based on the presence of key virulence gene sequences. This represents a novel insight into pathogen diversity within a single subtype and will inform future attempts to survey regional pathogen populations. PMID:28550057

Comprehensive Molecular Characterization of Escherichia coli Isolates from Urine Samples of Hospitalized Patients in Rio de Janeiro, Brazil

PubMed Central

Campos, Ana Carolina C.; Andrade, Nathália L.; Ferdous, Mithila; Chlebowicz, Monika A.; Santos, Carla C.; Correal, Julio C. D.; Lo Ten Foe, Jerome R.; Rosa, Ana Cláudia P.; Damasco, Paulo V.; Friedrich, Alex W.; Rossen, John W. A.

2018-01-01

Urinary tract infections (UTIs) are often caused by Escherichia coli. Their increasing resistance to broad-spectrum antibiotics challenges the treatment of UTIs. Whereas, E. coli ST131 is often multidrug resistant (MDR), ST69 remains susceptible to antibiotics such as cephalosporins. Both STs are commonly linked to community and nosocomial infections. E. coli phylogenetic groups B2 and D are associated with virulence and resistance profiles making them more pathogenic. Little is known about the population structure of E. coli isolates obtained from urine samples of hospitalized patients in Brazil. Therefore, we characterized E. coli isolated from urine samples of patients hospitalized at the university and three private hospitals in Rio de Janeiro, using whole genome sequencing. A high prevalence of E. coli ST131 and ST69 was found, but other lineages, namely ST73, ST648, ST405, and ST10 were also detected. Interestingly, isolates could be divided into two groups based on their antibiotic susceptibility. Isolates belonging to ST131, ST648, and ST405 showed a high resistance rate to all antibiotic classes tested, whereas isolates belonging to ST10, ST73, ST69 were in general susceptible to the antibiotics tested. Additionally, most ST69 isolates, normally resistant to aminoglycosides, were susceptible to this antibiotic in our population. The majority of ST131 isolates were ESBL-producing and belonged to serotype O25:H4 and the H30-R subclone. Previous studies showed that this subclone is often associated with more complicated UTIs, most likely due to their high resistance rate to different antibiotic classes. Sequenced isolates could be classified into five phylogenetic groups of which B2, D, and F showed higher resistance rates than groups A and B1. No significant difference for the predicted virulence genes scores was found for isolates belonging to ST131, ST648, ST405, and ST69. In contrast, the phylogenetic groups B2, D and F showed a higher predictive virulence score compared to phylogenetic groups A and B1. In conclusion, despite the diversity of E. coli isolates causing UTIs, clonal groups O25:H4-B2-ST131 H30-R, O1:H6-B2-ST648, and O102:H6-D-ST405 were the most prevalent. The emergence of highly virulent and MDR E. coli in Brazil is of high concern and requires more attention from the health authorities. PMID:29503639

Comprehensive Molecular Characterization of Escherichia coli Isolates from Urine Samples of Hospitalized Patients in Rio de Janeiro, Brazil.

PubMed

Campos, Ana Carolina C; Andrade, Nathália L; Ferdous, Mithila; Chlebowicz, Monika A; Santos, Carla C; Correal, Julio C D; Lo Ten Foe, Jerome R; Rosa, Ana Cláudia P; Damasco, Paulo V; Friedrich, Alex W; Rossen, John W A

2018-01-01

Urinary tract infections (UTIs) are often caused by Escherichia coli . Their increasing resistance to broad-spectrum antibiotics challenges the treatment of UTIs. Whereas, E. coli ST131 is often multidrug resistant (MDR), ST69 remains susceptible to antibiotics such as cephalosporins. Both STs are commonly linked to community and nosocomial infections. E. coli phylogenetic groups B2 and D are associated with virulence and resistance profiles making them more pathogenic. Little is known about the population structure of E. coli isolates obtained from urine samples of hospitalized patients in Brazil. Therefore, we characterized E. coli isolated from urine samples of patients hospitalized at the university and three private hospitals in Rio de Janeiro, using whole genome sequencing. A high prevalence of E. coli ST131 and ST69 was found, but other lineages, namely ST73, ST648, ST405, and ST10 were also detected. Interestingly, isolates could be divided into two groups based on their antibiotic susceptibility. Isolates belonging to ST131, ST648, and ST405 showed a high resistance rate to all antibiotic classes tested, whereas isolates belonging to ST10, ST73, ST69 were in general susceptible to the antibiotics tested. Additionally, most ST69 isolates, normally resistant to aminoglycosides, were susceptible to this antibiotic in our population. The majority of ST131 isolates were ESBL-producing and belonged to serotype O25:H4 and the H30-R subclone. Previous studies showed that this subclone is often associated with more complicated UTIs, most likely due to their high resistance rate to different antibiotic classes. Sequenced isolates could be classified into five phylogenetic groups of which B2, D, and F showed higher resistance rates than groups A and B1. No significant difference for the predicted virulence genes scores was found for isolates belonging to ST131, ST648, ST405, and ST69. In contrast, the phylogenetic groups B2, D and F showed a higher predictive virulence score compared to phylogenetic groups A and B1. In conclusion, despite the diversity of E. coli isolates causing UTIs, clonal groups O25:H4-B2-ST131 H30-R, O1:H6-B2-ST648, and O102:H6-D-ST405 were the most prevalent. The emergence of highly virulent and MDR E. coli in Brazil is of high concern and requires more attention from the health authorities.

Virulence and antimicrobial resistance determinants of verotoxigenic Escherichia coli (VTEC) and of multidrug-resistant E. coli from foods of animal origin illegally imported to the EU by flight passengers.

PubMed

Nagy, B; Szmolka, A; Smole Možina, S; Kovač, J; Strauss, A; Schlager, S; Beutlich, J; Appel, B; Lušicky, M; Aprikian, P; Pászti, J; Tóth, I; Kugler, R; Wagner, M

2015-09-16

The aim of this study was to reveal phenotype/genotype characteristics of verotoxigenic Escherichia coli (VTEC) and multidrug resistant E. coli in food products of animal origin confiscated as illegal import at Austrian, German and Slovenian airports. VTEC isolates were obtained by using ISO guidelines 16654:2001 for O157 VTEC or ISO/ TS13136:2012 for non-O157 VTEC, with additional use of the RIDASCREEN® Verotoxin immunoassay. The testing of 1526 samples resulted in 15 VTEC isolates (1.0%) primarily isolated from hard cheese from Turkey and Balkan countries. Genotyping for virulence by using a miniaturized microarray identified a wide range of virulence determinants. One VTEC isolate (O26:H46) possessing intimin (eae) and all other essential genes of Locus of Enterocyte Effacement (LEE) was designated as enterohemorrhagic E. coli (EHEC). None of the other VTEC strains belonged to serogroups O157, O145, O111, O104 or O103. VTEC strains harbored either stx(1) (variants stx1(a) or stx(1c)) or st(x2) (variants stx(2a), stx(2b), stx(2a/d) or stx(2c/d)) genes. Pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) demonstrated high genetic diversity and identified three new sequence types (STs): 4505, 4506 and 4507. Food samples collected from the Vienna airport were also tested for E. coli quantities using the ISO 16649:2001, and for detection of multidrug resistant phenotypes and genotypes. The resulting 113 commensal E. coli isolates were first tested in a pre-screening against 6 selected antimicrobials to demonstrate multidrug resistance. The resulting 14 multidrug resistant (MDR) E. coli isolates, representing 0.9% of the samples, were subjected to further resistance phenotyping and to microarray analyses targeting genetic markers of antimicrobial resistance and virulence. Genotyping revealed various combinations of resistance determinants as well as the presence of class 1, class 2 integrons. The isolates harbored 6 to 11 antibiotic resistance genes as well as 1 to 14 virulence genes. In this panel of 14 MDR E. coli two strains proved to carry CTX-M type ESBLs, and one single isolate was identified as enteropathogenic E. coli (EPEC). In general, isolates carrying a high number of resistance determinants had lower number of virulence genes and vice versa. In conclusion, this first pilot study on the prevalence of VTEC and of MDR/ESBL E. coli in illegally imported food products of animal origin suggests that these strains could represent reservoirs for dissemination of potentially new types of pathogenic and MDR E. coli in Europe. Copyright © 2015 Elsevier B.V. All rights reserved.

Bacteria isolated from companion animals in Japan (2014-2016) by blood culture.

PubMed

Tsuyuki, Yuzo; Kurita, Goro; Murata, Yoshiteru; Takahashi, Takashi

2018-02-24

We aimed to identify microorganisms isolated by blood culture (BC) from companion animals and to determine antimicrobial resistance of these isolates during 2014-2016 at veterinary laboratory, in comparison with those during 2010-2013, in Japan. Clinical data (animal species, visiting animals/hospitalized animals, and others except for disease type and clinical course including history of antimicrobial agent use) on ill animals at veterinary clinics or hospitals were obtained. We retrospectively analyzed animal-origin BC results extracted from the database in 2014-2016 and those obtained in 2010-2013. BC-positive samples were from most of dogs (n = 174 in 2014-2016 and n = 86 in 2010-2013). Escherichia coli (n = 50, 25.1%) and Staphylococcus intermedius group (SIG) bacteria (n = 23, 11.6%) were most prevalent in 2014-2016, while the percentages of E. coli (n = 22, 25.3%) and SIG (n = 9, 10.3%) in 2010-2013 were similar to those in 2014-2016. Percentages of extended-spectrum β-lactamase (ESBL)-producing E. coli and methicillin-resistant staphylococci (MRS) rate of SIG bacteria isolated in 2014-2016 were 28.0% and 69.6% (vs. 22.7% and 44.4% in 2010-2013), respectively. Fourteen ESBL-producing E. coli in 2014-2016 were isolated from 7 visiting animals and 7 hospitalized ones, whereas the sixteen MRS of SIG were from 7 visiting animals and 9 hospitalized ones. Our observations support the prevalent microorganisms isolated by BC and their antimicrobial resistance patterns for two study periods. Copyright © 2018 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Clustered, regularly interspaced short palindromic repeat (CRISPR) diversity and virulence factor distribution in avian Escherichia coli.

PubMed

Fu, Qiang; Su, Zhixin; Cheng, Yuqiang; Wang, Zhaofei; Li, Shiyu; Wang, Heng'an; Sun, Jianhe; Yan, Yaxian

In order to investigate the diverse characteristics of clustered, regularly interspaced short palindromic repeat (CRISPR) arrays and the distribution of virulence factor genes in avian Escherichia coli, 80 E. coli isolates obtained from chickens with avian pathogenic E. coli (APEC) or avian fecal commensal E. coli (AFEC) were identified. Using the multiplex polymerase chain reaction (PCR), five genes were subjected to phylogenetic typing and examined for CRISPR arrays to study genetic relatedness among the strains. The strains were further analyzed for CRISPR loci and virulence factor genes to determine a possible association between their CRISPR elements and their potential virulence. The strains were divided into five phylogenetic groups: A, B1, B2, D and E. It was confirmed that two types of CRISPR arrays, CRISPR1 and CRISPR2, which contain up to 246 distinct spacers, were amplified in most of the strains. Further classification of the isolates was achieved by sorting them into nine CRISPR clusters based on their spacer profiles, which indicates a candidate typing method for E. coli. Several significant differences in invasion-associated gene distribution were found between the APEC isolates and the AFEC isolates. Our results identified the distribution of 11 virulence genes and CRISPR diversity in 80 strains. It was demonstrated that, with the exception of iucD and aslA, there was no sharp demarcation in the gene distribution between the pathogenic (APEC) and commensal (AFEC) strains, while the total number of indicated CRISPR spacers may have a positive correlation with the potential pathogenicity of the E. coli isolates. Copyright © 2016. Published by Elsevier Masson SAS.

Effectiveness of steam pasteurization in controlling microbiological hazards of cull cow carcasses in a commercial plant

PubMed Central

2005-01-01

Abstract The purpose of the study, carried out in a beef processing plant, was to evaluate the effectiveness of a new prototype for steam pasteurization treatment in controlling microbiological hazards. Samples were taken by swabbing randomly selected sites before and after pasteurization and again after chilling to obtain total aerobic counts (TAC), total coliform counts (TCC), and generic Escherichia coli counts (ECC) on Petrifilm plates and to determine the prevalence of Salmonella spp., Listeria monocytogenes, and E. coli O157:H7 using standard enrichment techniques. Escherichia coli and L. monocytogenes strains were tested for various factors associated with their virulence by using colony hybridization and polymerase chain reaction (PCR), respectively. Antimicrobial susceptibility was determined for each isolate that was potentially pathogenic to humans by using the disk-diffusion method. Mean values for TAC, TCC, and ECC were 2.18, 0.16, and 0.06 log10 CFU/cm2, respectively, before pasteurization; 1.17, 0.03, and 0.01 log10 CFU/cm2 after pasteurization; and 0.89, 0.02, and 0.01 log10 CFU/cm2 after chilling. Prevalence of L. monocytogenes, Salmonella spp., and E. coli O157:H7 on carcasses was 0.8%, 0.0%, and 0.0%, respectively, before pasteurization; 2.6%, 0.0%, and 0.0% after pasteurization; and 3.1%, 0.1%, and 0.0% after chilling. The prevalence of E. coli containing ≥1 virulence gene was 14.7%. More specifically, 11.88% of the isolates obtained before pasteurization, 22.2% obtained after pasteurization, and 31.2% obtained after chilling had virulence genes. All L. monocytogenes isolates tested positive for the presence of 3 major virulence factors (hlyA, inlB, and plcB). Antibiograms showed that certain isolates were susceptible to all antibiotics, some showed an intermediate sensitivity, and others were multiresistant. Overall, these results suggest that steam pasteurization is an effective means of improving safety quality of beef carcasses. However, pasteurization may indirectly contribute to the growth of some pathogenic microorganisms, such as L. monocytogenes. PMID:16187550

High Diversity of Extended-Spectrum β-Lactamases in Escherichia coli Isolates from Italian Broiler Flocks ▿

PubMed Central

Bortolaia, Valeria; Guardabassi, Luca; Trevisani, Marcello; Bisgaard, Magne; Venturi, Luciano; Bojesen, Anders Miki

2010-01-01

We characterized 67 Escherichia coli isolates with reduced susceptibility to cefotaxime or ceftiofur obtained from healthy broilers housed in five Italian farms. The blaCTX-M-1, blaCTX-M-32 and blaSHV-12 β-lactamase genes were identified on IncI1, IncN, or IncFIB plasmids. Considerable genetic diversity was detected among the extended-spectrum β-lactamase (ESBL)-producing isolates, and we identified indistinguishable strains in unrelated farms and indistinguishable plasmids in genetically unrelated strains. The detection of highly mobile plasmids suggests a potential animal reservoir for β-lactamase genes. PMID:20100875

Phylogenetic Backgrounds and Virulence-Associated Traits of Escherichia coli Isolates from Surface Waters and Diverse Animals in Minnesota and Wisconsin.

PubMed

Johnson, James R; Johnston, Brian D; Delavari, Parissa; Thuras, Paul; Clabots, Connie; Sadowsky, Michael J

2017-12-15

Possible external reservoirs for extraintestinal pathogenic Escherichia coli (ExPEC) strains that cause infections in humans are poorly defined. Because of the tremendous human health importance of ExPEC infections, we assessed surface waters and domesticated and wild animals in Minnesota and Wisconsin as potential reservoirs of ExPEC of human health relevance. We characterized 595 E. coli isolates (obtained from 1999 to 2002; 280 from seven surface water sites, 315 from feces of 13 wild and domesticated animal species) for phylogroup and virulence genotype, including inferred ExPEC status, by using multiplex PCR-based methods. We also compared the pulsed-field gel electrophoresis (PFGE) profiles of the isolates with a large private PFGE profile library. We found a predominance of non-ExPEC strains (95% and 93% among water and animal isolates, respectively), which were mainly from phylogroups A and B1, plus a minority of ExPEC strains (5% and 7% among water isolates and animal isolates, respectively), predominantly from phylogroup B2. The ExPEC strains, although significantly associated with cats, dogs, and turkeys, occurred in several additional animal species (goat, horse, chicken, pig) and were distributed broadly across all surface water sites. Virulence gene content among the animal source ExPEC isolates segregated significantly in relation to host species, following established patterns. PFGE analysis indicated that 11 study isolates closely matched (94% to 100% profile similarity) reference human clinical and fecal isolates. These findings imply what probably is a low but non-zero risk to humans from environmental and animal source E. coli isolates, especially those from specific human-associated animal species. IMPORTANCE Our detection of potentially pathogenic strains that may pose a health threat to humans among E. coli isolates from surface waters and wild and domesticated animals suggests a need for heightened attention to these reservoirs as possible sources for human acquisition of disease-causing E. coli Although cats, dogs, and turkeys were especially high-prevalence sources, the presence of such strains in other animal species and at all sampled water sites suggests that this potential risk may be widespread. Copyright © 2017 American Society for Microbiology.

Molecular Characterization of Shiga Toxin-Producing Escherichia coli Strains Isolated in Poland.

PubMed

Januszkiewicz, Aleksandra; Rastawicki, Waldemar

2016-08-26

Shiga toxin-producing Escherichia coli (STEC) strains also called verotoxin-producing E. coli (VTEC) represent one of the most important groups of food-borne pathogens that can cause several human diseases such as hemorrhagic colitis (HC) and hemolytic - uremic syndrome (HUS) worldwide. The ability of STEC strains to cause disease is associated with the presence of wide range of identified and putative virulence factors including those encoding Shiga toxin. In this study, we examined the distribution of various virulence determinants among STEC strains isolated in Poland from different sources. A total of 71 Shiga toxin-producing E. coli strains isolated from human, cattle and food over the years 1996-2010 were characterized by microarray and PCR detection of virulence genes. As stx1a subtype was present in all of the tested Shiga toxin 1 producing E. coli strains, a greater diversity of subtypes was found in the gene stx2, which occurred in five subtypes: stx2a, stx2b, stx2c, stx2d, stx2g. Among STEC O157 strains we observed conserved core set of 14 virulence factors, stable in bacteria genome at long intervals of time. There was one cattle STEC isolate which possessed verotoxin gene as well as sta1 gene encoded heat-stable enterotoxin STIa characteristic for enterotoxigenic E. coli. To the best of our knowledge, this is the first comprehensive analysis of virulence gene profiles identified in STEC strains isolated from human, cattle and food in Poland. The results obtained using microarrays technology confirmed high effectiveness of this method in determining STEC virulotypes which provides data suitable for molecular risk assessment of the potential virulence of this bacteria. virulence factors including those encoding Shiga toxin. In this study, we examined the distribution of various virulence determinants among STEC strains isolated in Poland from different sources. A total of 71 Shiga toxin-producing E. coli strains isolated from human, cattle and food over the years 1996-2010 were characterized by microarray and PCR detection of virulence genes. As stx1a subtype was present in all of the tested Shiga toxin 1 producing E. coli strains, a greater diversity of subtypes was found in the gene stx2, which occurred in five subtypes: stx2a, stx2b, stx2c, stx2d, stx2g. Among STEC O157 strains we observed conserved core set of 14 virulence factors, stable in bacteria genome at long intervals of time. There was one cattle STEC isolate which possessed verotoxin gene as well as sta1 gene encoded heat-stable enterotoxin STIa characteristic for enterotoxigenic E. coli. To the best of our knowledge, this is the first comprehensive analysis of virulence gene profiles identified in STEC strains isolated from human, cattle and food in Poland. The results obtained using microarrays technology confirmed high effectiveness of this method in determining STEC virulotypes which provides data suitable for molecular risk assessment of the potential virulence of this bacteria.

Phagocytic resistance of Escherichia coli K-1 isolates and relationship to virulence.

PubMed Central

Weinstein, R; Young, L S

1978-01-01

Blood culture isolates from 133 episodes of Escherichia coli bacteremia were typed for K-1 capsular antigen by immunodiffusion, utilizing equine antiserum raised against meningococcal group B polysaccharide. Twenty-six percent (34 of 133) of these isolates were positive for K-1 antigen. These 133 strains, 34 K-1 and 99 non-K-1, were tested for susceptibility to phagocytosis. K-1 strains were found to be more resistant to clearance (27%) than non-K-1 strains (71%) when tested in an in vitro opsonophagocytic/killing assay containing normal human granulocytes and plasma. Additional studies demonstrated that resistance was due to decreased phagocytosis rather than diminished intraleukocytic killing. K-1 strains obtained from stool showed a similar degree of resistance to phagocytosis when compared with K-1 blood isolates. A comparison of clinical data on non-neonatal patients with E. coli K-1 and non-K-1 bacteremia showed no significant differences in mortality for these two groups. The incidence of shock for patients bacteremic with K-1 strains (74%) was significantly greater than that for patients bacteremic with non-K-1 strains (33%). These differences are attributed to the increased resistance to phagocytosis observed for K-1 versus non-K-1 E. coli isolates. Images PMID:370149

Aerobic bacteria occurring in the vagina of bitches with reproductive disorders.

PubMed

Bjurström, L

1993-01-01

A retrospective survey was performed of aerobic bacterial species found in the vagina of 203 bitches with genital disorders, e.g. infertility, vaginitis, pyometra and puppy death. Escherichia coli, beta-hemolytic streptococci, Staphylococcus intermedius and Pasteurella multocida were the species most often isolated. From bitches with pyometra E. coli in pure culture was the most frequent isolate. In contrast, the majority of infertile bitches gave rise to mixed cultures, and no specific bacterial species was consistently associated with infertility. Thus, bacterial sampling from infertile bitches was concluded to be of low diagnostic value. Bacterial species isolated from the bitches having vaginitis were present in pure culture in 26.9% of the samples while nonspecific mixed cultures were obtained from 34.6% of the samples from these bitches. E. coli was the most frequently isolated bacterial species from bitches with dead puppies. However, in such cases it is important to relate the vaginal bacterial findings to autopsy findings and the results of bacteriological cultures of the pups.

Restriction-Site-Specific PCR as a Rapid Test To Detect Enterohemorrhagic Escherichia coli O157:H7 Strains in Environmental Samples

PubMed Central

Kimura, Richard; Mandrell, Robert E.; Galland, John C.; Hyatt, Doreene; Riley, Lee W.

2000-01-01

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an important food-borne pathogen in industrialized countries. We developed a rapid and simple test for detecting E. coli O157:H7 using a method based on restriction site polymorphisms. Restriction-site-specific PCR (RSS-PCR) involves the amplification of DNA fragments using primers based on specific restriction enzyme recognition sequences, without the use of endonucleases, to generate a set of amplicons that yield “fingerprint” patterns when resolved electrophoretically on an agarose gel. The method was evaluated in a blinded study of E. coli isolates obtained from environmental samples collected at beef cattle feedyards. The 54 isolates were all initially identified by a commonly used polyclonal antibody test as belonging to O157:H7 serotype. They were retested by anti-O157 and anti-H7 monoclonal antibody enzyme-linked immunosorbent assay (ELISA). The RSS-PCR method identified all 28 isolates that were shown to be E. coli O157:H7 by the monoclonal antibody ELISA as belonging to the O157:H7 serotype. Of the remaining 26 ELISA-confirmed non-O157:H7 strains, the method classified 25 strains as non-O157:H7. The specificity of the RSS-PCR results correlated better with the monoclonal antibody ELISA than with the polyclonal antibody latex agglutination tests. The RSS-PCR method may be a useful test to distinguish E. coli O157:H7 from a large number of E. coli isolates from environmental samples. PMID:10831431

Ultrasonic isolation of the outer membrane of Escherichia coli with autodisplayed Z-domains.

PubMed

Bong, Ji-Hong; Yoo, Gu; Park, Min; Kang, Min-Jung; Jose, Joachim; Pyun, Jae-Chul

2014-11-01

The outer membrane of Escherichia coli was previously isolated as a liposome-like outer membrane particle using an enzymatic treatment for lysozymes; for immunoassays, the particles were subsequently layered on solid supports via hydrophobic interactions. This work presents an enzyme-free isolation method for the E. coli outer membrane with autodisplayed Z-domains using ultrasonication. First, the properties of the outer membrane particle, such as the particle size, zeta potential, and total protein, were compared with the properties of particles obtained using the previous preparation methods. Compared with the conventional isolation method using an enzyme treatment, the ultrasonic method exhibited a higher efficiency at isolating the outer membrane and less contamination by cytosolic proteins. The isolated outer membrane particles were layered on a gold surface, and the roughness and thickness of the layered outer membrane layers were subsequently analyzed using AFM analysis. Finally, the antibody-binding activity of two outer membrane layers with autodisplayed Z-domains created from particles that were isolated using the enzymatic and ultrasonic isolation methods was measured using fluorescein-labeled antibody as a model analyte, and the activity of the outer membrane layer that was isolated from the ultrasonic method was estimated to be more than 20% higher than that from the conventional enzymatic method. Copyright © 2014 Elsevier Inc. All rights reserved.

Fingerprints of resistant Escherichia coli O157:H7 from vegetables and environmental samples.

PubMed

Abakpa, Grace Onyukwo; Umoh, Veronica J; Kamaruzaman, Sijam; Ibekwe, Mark

2018-01-01

Some routes of transmission of Escherichia coli O157:H7 to fresh produce include contaminated irrigation water and manure polluted soils. The aim of the present study was to determine the genetic relationships of E. coli O157:H7 isolated from some produce growing region in Nigeria using enterobacterial repetitive intergenic consensus (ERIC) DNA fingerprinting analysis. A total of 440 samples comprising leafy greens, irrigation water, manure and soil were obtained from vegetable producing regions in Kano and Plateau States, Nigeria. Genes coding for the quinolone resistance-determinant (gyrA) and plasmid (pCT) coding for multidrug resistance (MDR) were determined using polymerase chain reaction (PCR) in 16 isolates that showed MDR. Cluster analysis of the ERIC-PCR profiles based on band sizes revealed six main clusters from the sixteen isolates analysed. The largest cluster (cluster 3) grouped isolates from vegetables and manure at a similarity coefficient of 0.72. The present study provides data that support the potential transmission of resistant strains of E. coli O157:H7 from vegetables and environmental sources to humans with potential public health implications, especially in developing countries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Identification of Genes Coding Aminoglycoside Modifying Enzymes in E. coli of UTI Patients in India.

PubMed

Mir, Abdul Rouf; Bashir, Yasir; Dar, Firdous Ahmad; Sekhar, M

This study is to probe the pattern of antibiotic resistance against aminoglycosides and its mechanism in E. coli obtained from patients from Chennai, India. Isolation and identification of pathogens were done on MacConkey agar. Antimicrobial sensitivity testing was done by disc diffusion test. The identification of genes encoding aminoglycoside modifying enzymes was done by Polymerase Chain Reaction (PCR). Out of 98 isolates, 71 (72.45%) isolates were identified as E. coli and the remaining 27 (27.55%) as other bacteria. Disc diffusion method results showed a resistance level of 72.15% for streptomycin, 73.4% for gentamicin, 63.26% for neomycin, 57.14% for tobramycin, 47.9% for netilmicin, and 8.16% for amikacin in E. coli. PCR screening showed the presence of four genes, namely, rrs, aacC2, aacA-aphD, and aphA3, in their plasmid DNA. The results point towards the novel mechanism of drug resistance in E. coli from UTI patients in India as they confirm the presence of genes encoding enzymes that cause resistance to aminoglycoside drugs. This could be an alarm for drug prescription to UTI patients.

Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario.

PubMed

Van Donkersgoed, Joyce; Manninen, Ken; Potter, Andy; McEwen, Scott; Bohaychuk, Valerie; Klashinsky, Sandy; Deckert, Anne; Irwin, Rebecca

2003-09-01

A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was < or = 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef.

Antimicrobial susceptibility of hazard analysis critical control point Escherichia coli isolates from federally inspected beef processing plants in Alberta, Saskatchewan, and Ontario

PubMed Central

Van Donkersgoed, Joyce; Manninen, Ken; Potter, Andy; McEwen, Scott; Bohaychuk, Valerie; Klashinsky, Sandy; Deckert, Anne; Irwin, Rebecca

2003-01-01

A survey to estimate the prevalence of antimicrobial resistance in Escherichia coli was conducted in 7 Canadian federally inspected processing plants during 2001. Escherichia coli isolates were recovered during routine hazard analysis critical control point sampling from beef carcasses and trim and subsequently tested for their antimicrobial susceptibility by using susceptibility panels. Of the 2653 isolates analyzed, 68% were sensitive to all 18 antimicrobials tested. For 14 of the 18 antimicrobials evaluated, the percentage of resistant isolates was ≤ 1. Twenty-five percent of the isolates were resistant to tetracycline, 9% to sulfamethoxazole, 7% to streptomycin, and 3% to ampicillin. Multiple resistance was found in 12% of the isolates, with 7% showing resistance to 2 antimicrobials, 2% to 3 antimicrobials, 2% to 4 antimicrobials, and 1% to 5 or more antimicrobials. Forty-five different antimicrobial resistance patterns were observed. The reasons for the development of the antimicrobial resistance were not investigated in this study. This study was useful as a pilot to help to develop a national antimicrobial resistance surveillance program in Canada. This study indicates that laboratory standardization is possible for consistent results across the country and that the indicator organism, E. coli, is fairly easy to obtain for surveillance but Salmonella are not, due to their low prevalence in beef. PMID:14524625

Prevalence and characteristics of ESBL-producing E. coli in Dutch recreational waters influenced by wastewater treatment plants.

PubMed

Blaak, Hetty; de Kruijf, Patrick; Hamidjaja, Raditijo A; van Hoek, Angela H A M; de Roda Husman, Ana Maria; Schets, Franciska M

2014-07-16

Outside health care settings, people may acquire ESBL-producing bacteria through different exposure routes, including contact with human or animal carriers or consumption of contaminated food. However, contact with faecally contaminated surface water may also represent a possible exposure route. The current study investigated the prevalence and characteristics of ESBL-producing Escherichia coli in four Dutch recreational waters and the possible role of nearby waste water treatment plants (WWTP) as contamination source. Isolates from recreational waters were compared with isolates from WWTP effluents, from surface water upstream of the WWTPs, at WWTP discharge points, and in connecting water bodies not influenced by the studied WWTPs. ESBL-producing E. coli were detected in all four recreational waters, with an average concentration of 1.3 colony forming units/100ml, and in 62% of all samples. In surface waters not influenced by the studied WWTPs, ESBL-producing E. coli were detected in similar concentrations, indicating the existence of additional ESBL-E. coli contamination sources. Isolates with identical ESBL-genes, phylogenetic background, antibiotic resistance profiles, and sequence type, were obtained from effluent and different surface water sites in the same watershed, on the same day; occasionally this included isolates from recreational waters. Recreational waters were identified as a potential exposure source of ESBL-producing E. coli. WWTPs were shown to contribute to the presence of these bacteria in surface waters, but other (yet unidentified) sources likely co-contribute. Copyright © 2014 Elsevier B.V. All rights reserved.

Molecular characterization of Shiga-toxigenic Escherichia coli isolated from diverse sources from India by multi-locus variable number tandem repeat analysis (MLVA).

PubMed

Kumar, A; Taneja, N; Sharma, R K; Sharma, H; Ramamurthy, T; Sharma, M

2014-12-01

In a first study from India, a diverse collection of 140 environmental and clinical non-O157 Shiga-toxigenic Escherichia coli strains from a large geographical area in north India was typed by multi-locus variable number tandem repeat analysis (MLVA). The distribution of major virulence genes stx1, stx2 and eae was found to be 78%, 70% and 10%, respectively; 15 isolates were enterohaemorrhagic E. coli (stx1 +/stx2 + and eae +). By MLVA analysis, 44 different alleles were obtained. Dendrogram analysis revealed 104 different genotypes and 19 MLVA-type complexes divided into two main lineages, i.e. mutton and animal stool. Human isolates presented a statistically significant greater odds ratio for clustering with mutton samples compared to animal stool isolates. Five human isolates clustered with animal stool strains suggesting that some of the human infections may be from cattle, perhaps through milk, contact or the environment. Further epidemiological studies are required to explore these sources in context with occurrence of human cases.

Methods for transforming and expression screening of filamentous fungal cells with a DNA library

DOEpatents

Teter, Sarah; Lamsa, Michael; Cherry, Joel; Ward, Connie

2015-06-02

The present invention relates to methods for expression screening of filamentous fungal transformants, comprising: (a) isolating single colony transformants of a DNA library introduced into E. coli; (b) preparing DNA from each of the single colony E. coli transformants; (c) introducing a sample of each of the DNA preparations of step (b) into separate suspensions of protoplasts of a filamentous fungus to obtain transformants thereof, wherein each transformant contains one or more copies of an individual polynucleotide from the DNA library; (d) growing the individual filamentous fungal transformants of step (c) on selective growth medium, thereby permitting growth of the filamentous fungal transformants, while suppressing growth of untransformed filamentous fungi; and (e) measuring activity or a property of each polypeptide encoded by the individual polynucleotides. The present invention also relates to isolated polynucleotides encoding polypeptides of interest obtained by such methods, to nucleic acid constructs, expression vectors, and recombinant host cells comprising the isolated polynucleotides, and to methods of producing the polypeptides encoded by the isolated polynucleotides.

Incidence and Characterization of Integrons, Genetic Elements Mediating Multiple-Drug Resistance, in Avian Escherichia coli

PubMed Central

Bass, Lydia; Liebert, Cynthia A.; Lee, Margie D.; Summers, Anne O.; White, David G.; Thayer, Stephan G.; Maurer, John J.

1999-01-01

Antibiotic resistance among avian bacterial isolates is common and is of great concern to the poultry industry. Approximately 36% (n = 100) of avian, pathogenic Escherichia coli isolates obtained from diseased poultry exhibited multiple-antibiotic resistance to tetracycline, oxytetracycline, streptomycin, sulfonamides, and gentamicin. Clinical avian E. coli isolates were further screened for the presence of markers for class 1 integrons, the integron recombinase intI1 and the quaternary ammonium resistance gene qacEΔ1, in order to determine the contribution of integrons to the observed multiple-antibiotic resistance phenotypes. Sixty-three percent of the clinical isolates were positive for the class 1 integron markers intI1 and qacEΔ1. PCR analysis with the conserved class 1 integron primers yielded amplicons of approximately 1 kb from E. coli isolates positive for intI1 and qacEΔ1. These PCR amplicons contained the spectinomycin-streptomycin resistance gene aadA1. Further characterization of the identified integrons revealed that many were part of the transposon Tn21, a genetic element that encodes both antibiotic resistance and heavy-metal resistance to mercuric compounds. Fifty percent of the clinical isolates positive for the integron marker gene intI1 as well as for the qacEΔ1 and aadA1 cassettes also contained the mercury reductase gene merA. The correlation between the presence of the merA gene with that of the integrase and antibiotic resistance genes suggests that these integrons are located in Tn21. The presence of these elements among avian E. coli isolates of diverse genetic makeup as well as in Salmonella suggests the mobility of Tn21 among pathogens in humans as well as poultry. PMID:10582884

Antimicrobial resistance of Escherichia coli isolates from broiler chickens and humans

PubMed Central

Miles, Tricia D; McLaughlin, Wayne; Brown, Paul D

2006-01-01

Background Antimicrobial usage is considered the most important factor promoting the emergence, selection and dissemination of antimicrobial-resistant microorganisms in both veterinary and human medicine. The aim of this study was to investigate the prevalence and genetic basis of tetracycline resistance in faecal Escherichia coli isolates from healthy broiler chickens and compare these data with isolates obtained from hospitalized patients in Jamaica. Results Eighty-two E. coli strains isolated from faecal samples of broiler chickens and urine and wound specimens of hospitalized patients were analyzed by agar disc diffusion to determine their susceptibility patterns to 11 antimicrobial agents. Tetracycline resistance determinants were investigated by plasmid profiling, transformations, and amplification of plasmid-borne resistance genes. Tetracycline resistance occurred at a frequency of 82.4% in avian isolates compared to 43.8% in human isolates. In addition, among avian isolates there was a trend towards higher resistance frequencies to kanamycin and nalidixic acid (p < 0.05), while a greater percentage of human isolates were resistant to chloramphenicol and gentamicin (p < 0.05). Multiple drug resistance was found in isolates from both sources and was usually associated with tetracycline resistance. Tetracycline-resistant isolates from both avian and human sources contained one or several plasmids, which were transmissible by transformation of chemically-competent E. coli. Tetracycline resistance was mediated by efflux genes tetB and/or tetD. Conclusion The present study highlights the prevalence of multiple drug resistant E. coli among healthy broiler chickens in Jamaica, possibly associated with expression of tetracycline resistance. While there did not appear to be a common source for multiple drug resistance in the strains from avian or human origin, the genes encoding resistance are similar. These results suggest that genes are disseminated in the environment and warrant further investigation of the possibility for avian sources acting as reservoirs for tetracycline resistance. PMID:16460561

Protective effects of indigenous Escherichia coli against a pathogenic E. coli challenge strain in pigs.

PubMed

Vahjen, W; Cuisiniere, T; Zentek, J

2017-10-13

To investigate the inhibitory effect of indigenous enterobacteria on pathogenic Escherichia coli, a challenge trial with postweaning pigs was conducted. A pathogenic E. coli strain was administered to all animals and their health was closely monitored thereafter. Faecal samples were taken from three healthy and three diarrhoeic animals. Samples were cultivated on MacConkey agar and isolates were subcultured. A soft agar overlay assay was used to determine the inhibitory activity of the isolates. A total of 1,173 enterobacterial isolates were screened for their ability to inhibit the E. coli challenge strain. Colony forming units of enterobacteria on MacConkey agar were not different between healthy and diarrhoeic animals in the original samples. Furthermore, numbers of isolates per animal were also not significantly different between healthy (482 isolates) and diarrhoeic animals (691 isolates). A total of 43 isolates (3.7%) with inhibitory activity against the pathogenic E. coli challenge strain were detected. All inhibitory isolates were identified as E. coli via MALDI-TOF. The isolates belonged to the phylotypes A, C and E. Many isolates (67.4%) were commensal E. coli without relevant porcine pathogenic factors, but toxin- and fimbrial genes (stx2e, fae, estIb, elt1a, fas, fan) were detected in 14 inhibitory isolates. Healthy animals showed significantly (P=0.003) more inhibitory isolates (36 of 482 isolates; 7.5%) than diseased animals (7 of 691 isolates; 1.0%). There were no significant correlations regarding phylotype or pathogenic factors between healthy and diseased animals. This study has shown that a small proportion of indigenous E. coli is able to inhibit in vitro growth of a pathogenic E. coli strain in pigs. Furthermore, healthy animals possess significantly more inhibitory E. coli strains than diarrhoeic animals. The inhibition of pathogenic E. coli by specific indigenous E. coli strains may be an underlying principle for the containment of pathogenic E. coli in pigs.

Characterization of antibiotic resistant and pathogenic Escherichia coli in irrigation water and vegetables in household farms.

PubMed

Araújo, Susana; A T Silva, Isabel; Tacão, Marta; Patinha, Carla; Alves, Artur; Henriques, Isabel

2017-09-18

This study aimed to characterize Escherichia coli present in irrigation water and vegetables from 16 household farms. Isolates were obtained from 50% of water (n=210 isolates) and 38% of vegetable samples (n=239). Phylogroups B1 (56% of isolates) and A (22%) were the most prevalent both in water and vegetables. Diarrheagenic strains were detected in vegetables. Irrespective of the source (i.e. water or vegetables), the most common antibiotic resistance was against streptomycin (89% resistant isolates) and tetracycline (24%). Common acquired genes (e.g. bla TEM , tetA, tetB) were found in isolates from both sources. Class I integrons were detected in water (arrays dfrA1-aadA1 and dfr16-blaP1b-aadA2-ereA) and vegetables (unknown arrays). intI2 was detected in water (dfrA1-sat2-aadA1). Plasmids were detected in 14 isolates (IncFIC, IncFIB, IncFrep, IncI1 in both samples; IncY in vegetables). Plasmids from seven isolates were transferrable by conjugation, conferring resistance to antibiotics to the recipient strain. Multidrug-resistant (MDR) strains were isolated from water (12% of the unique isolates) and vegetables (21%). Predominant sequence types (STs) among MDR isolates were ST10, ST297 and ST2522. In some cases, the same STs and identical clones (as showed by rep-PCR typing) were detected in water and vegetables, suggesting cross-contamination. This study identified several risk factors in E. coli isolates from vegetables and irrigation water, raising health concerns. Also, results suggest that irrigation groundwater constitutes a source of E. coli that may enter the food chain through vegetables ingestion. Copyright © 2017. Published by Elsevier B.V.

Presence of qnr gene in Escherichia coli and Klebsiella pneumoniae resistant to ciprofloxacin isolated from pediatric patients in China.

PubMed

Wang, Aihua; Yang, Yonghong; Lu, Quan; Wang, Yi; Chen, Yuan; Deng, Li; Ding, Hui; Deng, Qiulian; Zhang, Hong; Wang, Chuanqing; Liu, Lan; Xu, Xiwei; Wang, Li; Shen, Xuzhuang

2008-05-22

Quinolone resistance in Enterobacteriaceae results mainly from mutations in type II DNA topoisomerase genes and/or changes in the expression of outer membrane and efflux pumps. Several recent studies have indicated that plasmid-mediated resistance mechanisms also play a significant role in fluoroquinolone resistance, and its prevalence is increasing worldwide. In China, the presence of the qnr gene in the clinical isolates of Enterobacteriaceae has been reported, but this transmissible quinolone resistance gene has not been detected in strains isolated singly from pediatric patients. Because quinolones associated with a variety of adverse side effects on children, they are not authorized for pediatric use. This study therefore aimed to investigate the presence of the qnr gene in clinical isolates of E. coli and K. pneumoniae from pediatric patients in China. A total 213 of non-repetitive clinical isolates resistant to ciprofloxacin from E. coli and K. pneumoniae were collected from hospitalized patients at five children's hospital in Beijing, Shanghai, Guangzhou, and Chongqing. The isolates were screened for the plasmid-mediated quinolone resistance genes of qnrA, qnrB, and qnrS by PCR. Transferability was examined by conjugation with the sodium azide-resistant E. coli J53. All qnr-positive were analyzed for clonality by enterobacterial repetitive intergenic consensus (ERIC)-PCR. The study found that 19 ciprofloxacin-resistant clinical isolates of E. coli and K. pneumoniae were positive for the qnr gene, and most of the qnr positive strains were ESBL producers. Conjugation experiments showed that quinolone resitance could be transferred to recipients. Apart from this, different DNA banding patterns were obtained by ERIC-PCR from positive strains, which means that most of them were not clonally related. This report on transferable fluoroquinolone resistance due to the qnr gene among E. coli and K. pneumoniae strains indicated that plasmid-mediated quinolone resistance has emerged in pediatric patients in China.

Establishing the validity of different susceptibility testing methods to evaluate the in vitro activity of amoxicillin-clavulanate against Escherichia coli.

PubMed

María, Díez-Aguilar; María-Isabel, Morosini; María-Carmen, Conejo; Álvaro, Pascual; Jorge, Calvo; Luis, Martínez-Martínez; Francesc, Marco; Jordi, Vila; Adriana, Ortega; Jesús, Oteo; Rafael, Cantón

2016-04-01

Amoxicillin-clavulanate MICs of 160 Escherichia coli isolates with characterized resistance mechanisms were obtained by 2 MIC gradient strip brands, 3 automated systems, and reference ISO microdilution method using EUCAST (fixed 2μg/mL clavulanate) and CLSI (2:1 ratio) criteria. Discrepancies, mainly obtained with gradient strips, lead to an essential agreement range of 76.2-92.5. Copyright © 2016 Elsevier Inc. All rights reserved.

Virulence characteristics and genetic affinities of multiple drug resistant uropathogenic Escherichia coli from a semi urban locality in India.

PubMed

Jadhav, Savita; Hussain, Arif; Devi, Savita; Kumar, Ashutosh; Parveen, Sana; Gandham, Nageshwari; Wieler, Lothar H; Ewers, Christa; Ahmed, Niyaz

2011-03-25

Extraintestinal pathogenic Escherichia coli (ExPEC) are of significant health concern. The emergence of drug resistant E. coli with high virulence potential is alarming. Lack of sufficient data on transmission dynamics, virulence spectrum and antimicrobial resistance of certain pathogens such as the uropathogenic E. coli (UPEC) from countries with high infection burden, such as India, hinders the infection control and management efforts. In this study, we extensively genotyped and phenotyped a collection of 150 UPEC obtained from patients belonging to a semi-urban, industrialized setting near Pune, India. The isolates representing different clinical categories were analyzed in comparison with 50 commensal E. coli isolates from India as well as 50 ExPEC strains from Germany. Virulent strains were identified based on hemolysis, haemagglutination, cell surface hydrophobicity, serum bactericidal activity as well as with the help of O serotyping. We generated antimicrobial resistance profiles for all the clinical isolates and carried out phylogenetic analysis based on repetitive extragenic palindromic (rep)-PCR. E. coli from urinary tract infection cases expressed higher percentages of type I (45%) and P fimbriae (40%) when compared to fecal isolates (25% and 8% respectively). Hemolytic group comprised of 60% of UPEC and only 2% of E. coli from feces. Additionally, we found that serum resistance and cell surface hydrophobicity were not significantly (p = 0.16/p = 0.51) associated with UPEC from clinical cases. Moreover, clinical isolates exhibited highest resistance against amoxicillin (67.3%) and least against nitrofurantoin (57.3%). We also observed that 31.3% of UPEC were extended-spectrum beta-lactamase (ESBL) producers belonging to serotype O25, of which four were also positive for O25b subgroup that is linked to B2-O25b-ST131-CTX-M-15 virulent/multiresistant type. Furthermore, isolates from India and Germany (as well as global sources) were found to be genetically distinct with no evidence to espouse expansion of E. coli from India to the west or vice-versa.

Antibacterial activity of isolated phenolic compounds from cranberry (Vaccinium macrocarpon) against Escherichia coli.

PubMed

Rodríguez-Pérez, Celia; Quirantes-Piné, Rosa; Uberos, José; Jiménez-Sánchez, Cecilia; Peña, Alejandro; Segura-Carretero, Antonio

2016-03-01

Phenolic compounds from a cranberry extract were isolated in order to assess their contribution to the antibacterial activity against uropathogenic strains of Escherichia coli (UPEC). With this purpose, a total of 25 fractions from a cranberry extract were isolated using semipreparative high performance liquid chromatography (HPLC) and characterized based on the results obtained by reversed-phase HPLC coupled to mass spectrometry detection. Then, the effects on UPEC surface hydrophobicity and biofilm formation of the cranberry extract as well as the purest fractions (a total of 13) were tested. As expected, the whole extract presented a powerful antibacterial activity against UPEC while the selected fractions presented a different behavior. Myricetin and quercitrin significantly decreased (p < 0.05) E. coli biofilm formation compared with the control, while dihydroferulic acid glucuronide, procyanidin A dimer, quercetin glucoside, myricetin and prodelphinidin B led to a significant decrease of the surface hydrophobicity compared with the control. The results suggest that apart from proanthocyanidins, other compounds, mainly flavonoids, can act against E. coli biofilm formation and also modify UPEC surface hydrophobicity in vitro, one of the first steps of adhesion.

Differentiation of fecal Escherichia coli from poultry and free-living birds by (GTG)5-PCR genomic fingerprinting.

PubMed

Mohapatra, Bidyut R; Broersma, Klaas; Mazumder, Asit

2008-04-01

Determination of the non-point sources of fecal pollution is essential for the assessment of potential public health risk and development of appropriate management practices for prevention of further contamination. Repetitive extragenic palindromic-PCR coupled with (GTG)(5) primer [(GTG)(5)-PCR] was performed on 573 Escherichia coli isolates obtained from the feces of poultry (chicken, duck and turkey) and free-living (Canada goose, hawk, magpie, seagull and songbird) birds to evaluate the efficacy of (GTG)(5)-PCR genomic fingerprinting in the prediction of the correct source of fecal pollution. A discriminant analysis with the jack-knife algorithm of (GTG)(5)-PCR DNA fingerprints revealed that 95%, 94.1%, 93.2%, 84.6%, 79.7%, 76.7%, 75.3% and 70.7% of magpie, hawk, turkey, seagull, Canada goose, chicken, duck and songbird fecal E. coli isolates classified into the correct host source, respectively. The results of this study indicate that (GTG)(5)-PCR can be considered to be a complementary molecular tool for the rapid determination of E. coli isolates identity and tracking the non-point sources of fecal pollution.

[Antimicrobial sensitivity of Escherichia coli strains with K1 antigen isolated from pregnant women and newborns].

PubMed

Kaczmarek, Agnieszka; Budzyńska, Anna; Gospodarek, Eugenia

2011-01-01

The aim of this study was comparison of the susceptibility to antibiotics of E. coli strains with K1 antigen (E. coli K1+) and non-K1 E. coli strains (E. coli K1-). This study included 67 of E. coli K1+ and 67 of E. coli K1- strains isolated in the time period from June to September of 2008 from pregnant women and newborns hospitalized at dr. J. Biziel University Hospital number 2 L. Rydygier Collegium Medicum in Bydgoszcz Nicolaus Copernicus University in Toruń. Antimicrobial susceptibility of E. coli strains was tested by the disc-diffusion method, on the Mueller Hinton 2 Agar (Becton Dickinson). It was found that 64,2% of E. coli K1+ strains and 53,7% of E. coli K1-strains were susceptible to all tested antibiotics and chemioterapeutics. E. coli K1- strains were more often than E. coli K1+ nonsusceptible to at least one antimicrobial agent. The obtained results indicate that E. coli K1+ strains significant differed in the susceptibility to ampicillin/sulbactam (85,1% versus 95,5%) (p=0,041), cephalothin (70,1% versus 85,1%) (p=0,038) and tetracycline (91,0% versus 74,6%) (p=0,012) from E. coli K1-strains. All tested E. coli K1+ and K1-strains were sensitive to piperacillin/tazobactam, cefoperazone/sulbactam, cefotaxime, ceftazidime, cefepime, imipenem, amikacin, netilmicin and tigecycline. There weren't the ESBL-producing strains among tested E. coli K1+ and K1- rods.

Phylogenetic grouping and pathotypic comparison of urine and fecal Escherichia coli isolates from children with urinary tract infection.

PubMed

Navidinia, Masoumeh; Peerayeh, Shahin Najar; Fallah, Fatemeh; Bakhshi, Bita; Sajadinia, Raheleh Sadat

2014-01-01

The aim of this study was to investigate the phylogenetic background and to assess hlyD (involved in the secretion of haemolysin A) and intI1 (encoding a class 1 integrase) in Escherichia coli isolates derived from urinary and fecal specimens. A total of 200 E. coli isolates was collected from patients presenting with urinary tract infection (UTI) during September 2009 to September 2010 and screened for hlyD and intI1 genes by polymerase chain reaction (PCR). Phylogenetic analysis showed that E. coli is composed of four main phylogenetic groups (A, B1, B2 and D) and that uropathogenic E. coli (UPEC) isolates mainly belong to groups B2 (54%) and D (34%) whereas group A (44%) and D (26%) are predominant among commensal E. coli isolates. In this study, hlyD was present in 26% of UPEC and 2% of commensal E. coli isolates. However, hemolytic activity was detected for 42% of UPEC and 6% of commensal E. coli isolates (p < 0.05). intI1 gene was more frequently expressed in UPEC (24%) in comparison with commensal E. coli isolates (12%). Resistance to aztreonam, co-trimoxazole and cefpodoxime were frequently found among UPEC isolates whereas commensal E. coli isolates were commonly resistant to co-trimoxazole, nalidixic acid and cefotaxime. Concluding, a considerable difference between UPEC and commensal E. coli isolates was observed regarding their phylogenetic groups, presence of class 1 integron and hlyD gene, hemolysin activity and resistance pattern. The detection of class 1 integrons and hlyD gene was higher among UPEC compared with commensal E. coli isolates. These findings may contribute for a better understanding of the factors involved in the pathogenesis of UPEC.

Overexpression of Salmonella enterica serovar Typhi recA gene confers fluoroquinolone resistance in Escherichia coli DH5α.

PubMed

Yassien, M A M; Elfaky, M A

2015-11-01

A spontaneous fluoroquinolone-resistant mutant (STM1) was isolated from its parent Salmonella enterica serovar Typhi (S. Typhi) clinical isolate. Unlike its parent isolate, this mutant has selective resistance to fluoroquinolones without any change in its sensitivity to various other antibiotics. DNA gyrase assays revealed that the fluoroquinolone resistance phenotype of the STM1 mutant did not result from alteration of the fluoroquinolone sensitivity of the DNA gyrase isolated from it. To study the mechanism of fluoroquinolone resistance, a genomic library from the STM1 mutant was constructed in Escherichia coli DH5α and two recombinant plasmids were obtained. Only one of these plasmids (STM1-A) conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. The chromosomal insert from STM1-A, digested with EcoRI and HindIII restriction endonucleases, produced two DNA fragments and these were cloned separately into pUC19 thereby generating two new plasmids, STM1-A1 and STM1-A2. Only STM1-A1 conferred the selective fluoroquinolone resistance phenotype to E. coli DH5α. Sequence and subcloning analyses of STM1-A1 showed the presence of an intact RecA open reading frame. Unlike that of the wild-type E. coli DH5α, protein analysis of a crude STM1-A1 extract showed overexpression of a 40 kDa protein. Western blotting confirmed the 40 kDa protein band to be RecA. When a RecA PCR product was cloned into pGEM-T and introduced into E. coli DH5α, the STM1-A11 subclone retained fluoroquinolone resistance. These results suggest that overexpression of RecA causes selective fluoroquinolone resistance in E. coli DH5α.

Serotypes, Virulence Factors, and Antimicrobial Susceptibilities of Vaginal and Fecal Isolates of Escherichia coli from Giant Pandas

PubMed Central

Wang, Xin; Xia, Xiaodong; Li, Desheng; Wang, Chengdong; Chen, Shijie; Hou, Rong

2013-01-01

Although Escherichia coli typically colonizes the intestinal tract and vagina of giant pandas, it has caused enteric and systemic disease in giant pandas and greatly impacts the health and survival of this endangered species. In order to understand the distribution and characteristics of E. coli from giant pandas, 67 fecal and 30 vaginal E. coli isolates from 21 giant pandas were characterized for O serogroups, phylogenetic groups, antimicrobial susceptibilities, and pulsed-field gel electrophoresis (PFGE) profiles. In addition, these isolates were tested for the presence of extraintestinal pathogenic E. coli (ExPEC) and diarrheagenic E. coli (DEC) by multiplex PCR detection of specific virulence genes. The most prevalent serogroups for all E. coli isolates were O88, O18, O167, O4, and O158. ExPEC isolates were detected mostly in vaginal samples, and DEC isolates were detected only in fecal samples. Phylogenetic group B1 predominated in fecal isolates, while groups B2 and D were frequently detected in vaginal isolates. Resistance to trimethoprim-sulfamethoxazole was most frequently observed, followed by resistance to nalidixic acid and tetracycline. All except five isolates were typeable by using XbaI and were categorized into 74 PFGE patterns. Our findings indicate that panda E. coli isolates exhibited antimicrobial resistance, and potentially pathogenic E. coli isolates were present in giant pandas. In addition, these E. coli isolates were genetically diverse. This study may provide helpful information for developing strategies in the future to control E. coli infections of giant pandas. PMID:23793635

Serotypes, virulence factors, and antimicrobial susceptibilities of vaginal and fecal isolates of Escherichia coli from giant pandas.

PubMed

Wang, Xin; Yan, Qigui; Xia, Xiaodong; Zhang, Yanming; Li, Desheng; Wang, Chengdong; Chen, Shijie; Hou, Rong

2013-09-01

Although Escherichia coli typically colonizes the intestinal tract and vagina of giant pandas, it has caused enteric and systemic disease in giant pandas and greatly impacts the health and survival of this endangered species. In order to understand the distribution and characteristics of E. coli from giant pandas, 67 fecal and 30 vaginal E. coli isolates from 21 giant pandas were characterized for O serogroups, phylogenetic groups, antimicrobial susceptibilities, and pulsed-field gel electrophoresis (PFGE) profiles. In addition, these isolates were tested for the presence of extraintestinal pathogenic E. coli (ExPEC) and diarrheagenic E. coli (DEC) by multiplex PCR detection of specific virulence genes. The most prevalent serogroups for all E. coli isolates were O88, O18, O167, O4, and O158. ExPEC isolates were detected mostly in vaginal samples, and DEC isolates were detected only in fecal samples. Phylogenetic group B1 predominated in fecal isolates, while groups B2 and D were frequently detected in vaginal isolates. Resistance to trimethoprim-sulfamethoxazole was most frequently observed, followed by resistance to nalidixic acid and tetracycline. All except five isolates were typeable by using XbaI and were categorized into 74 PFGE patterns. Our findings indicate that panda E. coli isolates exhibited antimicrobial resistance, and potentially pathogenic E. coli isolates were present in giant pandas. In addition, these E. coli isolates were genetically diverse. This study may provide helpful information for developing strategies in the future to control E. coli infections of giant pandas.

[The occurrence of Escherichia coli with K1 surface antigen in pregnant women and in newborns].

PubMed

Kaczmarek, Agnieszka; Budzyńska, Anna; Gospodarek, Eugenia

2010-01-01

The aim of the study was to determine the frequency of occurrence of K1 surface antigen in Escherichia coli strains isolated from the pregnant women and newborns. A total of 425 of E. coli strains isolated from the faecal samples, 67 strains isolated from the vagina of pregnant women and 40 strains isolated from the newborns' nasal cavity were included into the study. All strains were collected between June and September of 2008. Identification of isolates was followed by the assessment of presence of K1 surface antigen in E. coli strains. The presence of K1 antigen was found in 17,6% of E. coli strains isolated from the faecal samples, 20,9% of E. coli strains isolated from the vagina of pregnant women and in 17,5% of E. coli strains isolated from the newborns' nasal cavity. Routine screening of E. coli K1 colonization gives an opportunity to identify women with the risk of E. coli K1 transmission to neonates during delivery and thereby with major probability of perinatal infections. Latex agglutination test Pastorex Meningitis (Bio-Rad) provides fast identification of E. coli K1 strains.

Characterization of Shiga Toxigenic Escherichia coli O157 and Non-O157 Isolates from Ruminant Feces in Malaysia

PubMed Central

Perera, Asanthi; Clarke, Charles M.; Dykes, Gary A.; Fegan, Narelle

2015-01-01

Shiga toxigenic Escherichia coli (STEC) O157 and several other serogroups of non-O157 STEC are causative agents of severe disease in humans world-wide. The present study was conducted to characterize STEC O157 and non-O157 serogroups O26, O103, O111, O121, O45, and O145 in ruminants in Malaysia. A total of 136 ruminant feces samples were collected from 6 different farms in Peninsular Malaysia. Immunomagnetic beads were used to isolate E. coli O157 and non-O157 serogroups, while PCR was used for the detection and subtyping of STEC isolates. STEC O157:H7 was isolated from 6 (4%) feces samples and all isolates obtained carried stx 2c,  eaeA-γ1, and ehxA. Non-O157 STEC was isolated from 2 (1.5%) feces samples with one isolate carrying stx 1a, stx 2a, stx 2c, and ehxA and the other carrying stx 1a alone. The presence of STEC O157 and non-O157 in a small percentage of ruminants in this study together with their virulence characteristics suggests that they may have limited impact on public health. PMID:26539484

Occurrence of pathogenicity island I(APEC-O1) genes among Escherichia coli implicated in avian colibacillosis.

PubMed

Kariyawasam, Subhashinie; Johnson, Timothy J; Debroy, Chitrita; Nolan, Lisa K

2006-09-01

Colibacillosis caused by avian pathogenic Escherichia coli (APEC) is a leading cause of economic loss to the poultry industry worldwide. The ability of APEC to cause disease is determined by certain virulence markers, some of which are located on pathogenicity islands (PAls). We recently described one such PAI in an APEC O1:K1 strain (APEC-O1). This PAI, termed PAI I(APEC-O1), carries the genes of the pap operon, a region similar to the tia invasion determinant of enterotoxigenic E coli; ireA, a gene that encodes an iron-responsive element; and a novel 1.5-kb region, ORF 54. Here, the occurrence of six selected loci of PAI I(APEC-O1) (papA, papC, papG, ireA, tia, and ORF 54) among APEC and fecal E. coli strains from apparently healthy chickens (avian commensal E. coli) was determined using polymerase chain reaction (PCR) techniques. None of the commensal E. coli was positive for all six traits, whereas 7.2% of the APEC isolates were positive for all the traits. Although there was no significant difference in the occurrence of ORF 54 among APEC and commensal E. coli, tia, ireA, papC, and papG genes were predominantly present in APEC rather than in avian commensal E. coli. papA was detected in only 6.3% of APEC, perhaps because of the presence of allelic variants of the gene. Additionally, the presence of all six traits was tested with PCR in APEC isolates collected in the 1980s, and these results were compared with those obtained with the APEC isolated in the 1990s. There was no significant difference in the occurrence of tia, ireA, papC, papG, and ORF 54 between APEC isolates collected during the different decades. However, papA was more frequently present in APEC from the 1980s than it was in APEC from the 1990s. Phylogenetic group of an isolate did not correlate with pathogenicity or the presence of PAI traits, except that more APEC of the low-pathogenicity group belonged to the phylogenetic group B1. However, PAI traits occurred more frequently in isolates belonging to the intermediate- and high-pathogenicity groups than in isolates of low pathogenicity.

Genotypic and phenotypic profiles of Escherichia coli isolates belonging to clinical sequence type 131 (ST131), clinical non-ST131, and fecal non-ST131 lineages from India.

PubMed

Hussain, Arif; Ranjan, Amit; Nandanwar, Nishant; Babbar, Anshu; Jadhav, Savita; Ahmed, Niyaz

2014-12-01

In view of the epidemiological success of CTX-M-15-producing lineages of Escherichia coli and particularly of sequence type 131 (ST131), it is of significant interest to explore its prevalence in countries such as India and to determine if antibiotic resistance, virulence, metabolic potential, and/or the genetic architecture of the ST131 isolates differ from those of non-ST131 isolates. A collection of 126 E. coli isolates comprising 43 ST131 E. coli, 40 non-ST131 E. coli, and 43 fecal E. coli isolates collected from a tertiary care hospital in India was analyzed. These isolates were subjected to enterobacterial repetitive intergenic consensus (ERIC)-based fingerprinting, O typing, phylogenetic grouping, antibiotic sensitivity testing, and virulence and antimicrobial resistance gene (VAG) detection. Representative isolates from this collection were also analyzed by multilocus sequence typing (MLST), conjugation, metabolic profiling, biofilm production assay, and zebra fish lethality assay. All of the 43 ST131 E. coli isolates were exclusively associated with phylogenetic group B2 (100%), while most of the clinical non-ST131 and stool non-ST131 E. coli isolates were affiliated with the B2 (38%) and A (58%) phylogenetic groups, respectively. Significantly greater proportions of ST131 isolates (58%) than non-ST131 isolates (clinical and stool E. coli isolates, 5% each) were technically identified to be extraintestinal pathogenic E. coli (ExPEC). The clinical ST131, clinical non-ST131, and stool non-ST131 E. coli isolates exhibited high rates of multidrug resistance (95%, 91%, and 91%, respectively), extended-spectrum-β-lactamase (ESBL) production (86%, 83%, and 91%, respectively), and metallo-β-lactamase (MBL) production (28%, 33%, and 0%, respectively). CTX-M-15 was strongly linked with ESBL production in ST131 isolates (93%), whereas CTX-M-15 plus TEM were present in clinical and stool non-ST131 E. coli isolates. Using MLST, we confirmed the presence of two NDM-1-positive ST131 E. coli isolates. The aggregate bioscores (metabolite utilization) for ST131, clinical non-ST131, and stool non-ST131 E. coli isolates were 53%, 52%, and 49%, respectively. The ST131 isolates were moderate biofilm producers and were more highly virulent in zebra fish than non-ST131 isolates. According to ERIC-based fingerprinting, the ST131 strains were more genetically similar, and this was subsequently followed by the genetic similarity of clinical non-ST131 and stool non-ST131 E. coli strains. In conclusion, our data provide novel insights into aspects of the fitness advantage of E. coli lineage ST131 and suggest that a number of factors are likely involved in the worldwide dissemination of and infections due to ST131 E. coli isolates. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Involvement of main diarrheagenic Escherichia coli, with emphasis on enteroaggregative E. coli, in severe non-epidemic pediatric diarrhea in a high-income country.

PubMed

Tobias, Joshua; Kassem, Eias; Rubinstein, Uri; Bialik, Anya; Vutukuru, Sreekanth-Reddy; Navaro, Armando; Rokney, Assaf; Valinsky, Lea; Ephros, Moshe; Cohen, Dani; Muhsen, Khitam

2015-02-21

Bacterial and viral enteric pathogens are the leading cause of diarrhea in infants and children. We aimed to identify and characterize the main human diarrheagenic E. coli (DEC) in stool samples obtained from children less than 5 years of age, hospitalized for acute gastroenteritis in Israel, and to examine the hypothesis that co-infection with DEC and other enteropathogens is associated with the severity of symptoms. Stool specimens obtained from 307 patients were tested by multiplex PCR (mPCR) to identify enteroaggregative E. coli (EAEC), enterohemorrhagic (EHEC), enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). Specimens were also examined for the presence of rotavirus by immunochromatography, and of Shigella, Salmonella and Campylobacter by stool culture; clinical information was also obtained. Fifty nine (19%) children tested positive for DEC; EAEC and atypical EPEC were most common, each detected in 27 (46%), followed by ETEC (n = 3; 5%), EHEC and typical EPEC (each in 1 child; 1.5%). Most EAEC isolates were resistant to cephalexin, cefixime, cephalothin and ampicillin, and genotypic characterization of EAEC isolates by O-typing and pulsed-field gel electrophoresis showed possible clonal relatedness among some. The likelihood of having > 10 loose/watery stools on the most severe day of illness was significantly increased among patients with EAEC and rotavirus co-infection compared to children who tested negative for both pathogens: adjusted odds ratio 7.0 (95% CI 1.45-33.71, P = 0.015). DEC was common in this pediatric population, in a high-income country, and mixed EAEC and rotavirus infection was characterized by especially severe diarrhea.

Environmental emission of multiresistant Escherichia coli carrying the colistin resistance gene mcr-1 from German swine farms.

PubMed

Guenther, Sebastian; Falgenhauer, Linda; Semmler, Torsten; Imirzalioglu, Can; Chakraborty, Trinad; Roesler, Uwe; Roschanski, Nicole

2017-05-01

Pigs have been the focus of the worldwide spread of colistin resistance. However, there is little information on the transmission of mcr-1 -containing bacteria into the environment of pig farms. We therefore rescreened environmental Escherichia coli isolates from the surrounding farm areas of three previously mcr-1 -positive swine herds in Germany. Thirty-five mixed bacterial cultures obtained from boot swabs, flies, dog faeces and manure from three pig farms in Germany in 2011-12 were non-selectively recultivated and the presence of the mcr-1 gene was checked by real-time PCR. After separation, single E. coli colonies were subsequently isolated and the presence of mcr-1 was confirmed by PCR and sequencing. In addition, phenotypic antimicrobial resistance screening and WGS followed by phylogenetic analysis and resistance genotyping as well as plasmid typing were performed. Seven mcr-1 -positive E. coli strains originating from environmental boot swabs, dog faeces, stable flies and manure were found. The isolates belonged to five different STs (ST10, ST1011, ST1140, ST5281 and ST342) and harboured extensive additional resistance genes. Comparative plasmid analysis predominantly located mcr-1 on IncX4 plasmids, which are strongly related to a recently described plasmid of human clinical origin (pICBEC72Hmcr). WGS-based analysis of the environmental E. coli isolates of farm surroundings showed clear links to mcr-1 -harbouring E. coli recovered from pig production in Europe as well as from human clinical isolates worldwide, presenting another piece of the puzzle, which further complicates the rapidly evolving epidemiology of plasmid-mediated colistin-resistant E. coli strains. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[In-vitro activity of mecillinam against urine isolates of Escherichia coli from outpatient departments in Germany].

PubMed

Kresken, Michael; Körber-Irrgang, Barbara; Naber, Kurt G

2017-05-01

National and international guidelines recommend fosfomycin trometamol, nitrofurantoin, nitroxoline, and pivmecillinam as first-line agents for the treatment of acute uncomplicated cystitis. Escherichia coli is by far the leading cause of community-acquired urinary tract infections. Pivmecillinam (X-SYSTO ® ) is an oral prodrug of mecillinam, a penicillin derivative that was reintroduced to the German market in March 2016. This study aimed to investigate the proportion of mecillinam-resistant strains among E. coli isolates prior to the introduction of X-SYSTO ® in Germany.An in-vitro study was carried out to determine the minimal inhibitory concentrations (MICs) of mecillinam against 494 urine isolates of E. coli (including multidrug-resistant strains). Isolates were obtained from outpatients and collected in 25 laboratories between October and December 2013. MIC breakpoints defined by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) were applied for classifying the bacterial isolates as mecillinam-susceptible (MIC ≤ 8 mg/l) or resistant (MIC > 8 mg/l).The concentrations of mecillinam needed to inhibit 50 % and 90 % of the test isolates were 1 and 4 mg/l, respectively, for isolates displaying the extended spectrum β-lactamase phenotype, and 0.25 and 4 mg/l, respectively, for the remaining isolates. Overall, 98 % of the isolates were found to be mecillinam-susceptible (MIC ≤ 8 mg/l), and 2 % were found to be resistant (MIC > 8 mg/l).These findings support the recommendation to regard pivmecillinam as a first-line option for the treatment of acute uncomplicated cystitis. © Georg Thieme Verlag KG Stuttgart · New York.

Prevalence and Antimicrobial Susceptibility Pattern of E. coli O157:H7 Isolated from Traditionally Marketed Raw Cow Milk in and around Asosa Town, Western Ethiopia.

PubMed

Disassa, Nigatu; Sibhat, Berhanu; Mengistu, Shimelis; Muktar, Yimer; Belina, Dinaol

2017-01-01

A cross-sectional study was conducted from October 2014 to July 2015 to determine the prevalence and populations of E. coli as well as the prevalence and antimicrobial susceptibility of E. coli O157:H7 isolated from raw milk. Biochemical and serological tests methods were used to confirm E. coli and E. coli O157:H7 and isolates were subjected to antimicrobial susceptibility test using the agar disc diffusion method. Out of 380 raw milk samples examined, 129 (33.9%) and 11 (2.9%) were contaminated with E. coli and E. coli O157:H7, respectively. The highest prevalence was recorded in samples obtained from vendors (39.1%, 4.978 ± 0.180 log 10 /ml) compared with samples from farmers (28.1%, 3.93 ± 0.01 log 10 /ml) with significant differences ( P = 0.02). The frequency of contamination was higher in the samples collected from milk that was stored and transported in plastic containers (39.4%) than in the containers made of stainless steel (23.0%) ( P = 0.002). The antimicrobial susceptibility profile showed that E. coli O157:H7 were resistant to tetracycline (81.8%), streptomycin (81.8%), and kanamycin (63.6%). Milk samples were produced and handled under poor hygienic conditions, stored, and transported in inappropriate containers and under temperature abuse conditions leading to high health risk to the consumers. Additional studies would be needed to establish association between the occurrences of E. coli O157:H7 in raw milk and all the risk factors involved in and around Asosa town.

3M™ Molecular detection system versus MALDI-TOF mass spectrometry and molecular techniques for the identification of Escherichia coli 0157:H7, Salmonella spp. &Listeria spp.

PubMed

Loff, Marché; Mare, Louise; de Kwaadsteniet, Michele; Khan, Wesaal

2014-06-01

The aim of this study was to compare standard selective plating, conventional PCR (16S rRNA and species specific primers), MALDI-TOF MS and the 3M™ Molecular Detection System for the routine detection of the pathogens Listeria, Salmonella and Escherichia coli 0157:H7 in wastewater and river water samples. MALDI-TOF MS was able to positively identify 20/21 (95%) of the E. coli isolates obtained at genus and species level, while 16S rRNA sequencing only correctly identified 6/21 (28%) as E. coli strains. None of the presumptive positive Listeria spp. and Salmonella spp. isolates obtained by culturing on selective media were positively identified by MALDI-TOF and 16S rRNA analysis. The species-specific E. coli 0157:H7 PCR described in this present study, was not able to detect any E. coli 0157:H7 strains in the wastewater and river water samples analysed. However, E. coli strains, Listeria spp., L. monocytogenes and Salmonella spp. were detected using species specific PCR. Escherichia coli 0157:H7, Listeria spp. and Salmonella spp. were also sporadically detected throughout the sampling period in the wastewater and river water samples analysed by the 3M™ Molecular Detection System. MALDI-TOF MS, which is a simple, accurate and cost-effective detection method, efficiently identified the culturable organisms, while in the current study both species specific PCR (Listeria spp. and Salmonella spp.) and 3M™ Molecular Detection System could be utilised for the direct routine analysis of pathogens in water sources. Copyright © 2014 Elsevier B.V. All rights reserved.

Occurrence and antimicrobial drug susceptibility patterns of commensal and diarrheagenic Escherichia coli in fecal microbiota from children with and without acute diarrhea.

PubMed

Garcia, Patrícia G; Silva, Vânia L; Diniz, Cláudio G

2011-02-01

Acute diarrhea is a public health problem and an important cause of morbidity and mortality, especially in developing countries. The etiology is varied, and the diarrheagenic Escherichia coli pathotypes are among the most important. Our objectives were to determine the occurrence of commensal and diarrheagenic E. coli strains in fecal samples from children under five years old and their drug susceptibility patterns. E. coli were isolated from 141 fresh fecal samples; 84 were obtained from clinically injured donors with acute diarrhea (AD) and 57 from clinically healthy donors without diarrhea (WD). Presumptive phenotypic species identification was carried out and confirmed by amplification of specific 16S ribosomal RNA encoding DNA. Multiplex PCR was performed to characterize the diarrheagenic E. coli strains. Drug susceptibility patterns were determined by the disc-diffusion method. In total, 220 strains were recovered from the fecal specimens (61.8% from AD and 38.2% from WD). Diarrheagenic E. coli was identified at a rate of 36.8% (n=50) in diarrheic feces and 29.8% (n=25) in non-diarrheic feces. Enteroaggregative E. coli was the most frequently identified pathotype in the AD group (16.2%) and the only pathotype identified in the WD group (30.9%). Enteropathogenic E. coli was the second most isolated pathotype (10.3%), followed by Shiga toxin-producing E. coli (7.4%) and enterotoxigenic E. coli (2.9%). No enteroinvasive E. coli strains were recovered. The isolates showed high resistance rates against ampicillin, tetracycline, and sulfamethoxazole-trimethoprim. The most effective drugs were ceftazidime, ceftriaxone, imipenem and piperacillin-tazobactam, for which no resistance was observed. Differentiation between the diarrheagenic E. coli pathotypes is of great importance since they are involved in acute diarrheal diseases and may require specific antimicrobial chemotherapy. The high antimicrobial resistance observed in our study raises a broad discussion on the indiscriminate or improper use of antimicrobials, besides the risks of self-medication.

Characterization of bacterial strains isolated from a beef-processing plant following cleaning and disinfection - Influence of isolated strains on biofilm formation by Sakaï and EDL 933 E. coli O157:H7.

PubMed

Marouani-Gadri, Nesrine; Augier, Gladys; Carpentier, Brigitte

2009-07-31

The objective of this study was to investigate the effects on Escherichia coli O157:H7 biofilm formation of bacteria isolated from meat site surfaces following cleaning and disinfection. We first isolated and identified, to the genus level, strains of the latter organisms. Samples were obtained by swabbing the surfaces of equipment or floors over areas ranging from 315 to 3200 cm(2) in a slaughter hall, a meat cutting room and a meat boning room of a meat-processing plant. The number of bacteria recovered from these surfaces ranged from <1 to> 10(5) CFU/cm(2). In the slaughter hall, stainless steel was in one case one of the most contaminated materials and in other cases one of the less contaminated. The same observation was made for conveyor belts made of polyvinyl chloride in the boning room. Dominant genera in the meat plant were Staphylococcus and Bacillus which were both 34% of the isolates from the slaughter hall and 14 and 4% respectively of the isolates from the cutting room. Randomly selected isolates of each of the genera recovered from the slaughter hall were cultured with E. coli O157:H7 in meat exudate at 15 degrees C to form dual-organism biofilms on polyurethane. In all cases but one, the isolates increased the numbers of attached E. coli O157:H7. The effects ranged from 0.37 to 1.11 for EDL 933 strain and from 0.19 to 1.38 log (CFU/cm(2)) for Sakaï strain. This is the first time that a resident microbiota of a meat-processing plant has been shown to have a favourable effect on E. coli O157:H7 colonization of a solid surface, which is of great interest from a food safety standpoint.

Escherichia coli O104 in Feedlot Cattle Feces: Prevalence, Isolation and Characterization.

PubMed

Shridhar, Pragathi B; Noll, Lance W; Shi, Xiaorong; Cernicchiaro, Natalia; Renter, David G; Bai, J; Nagaraja, T G

2016-01-01

Escherichia coli O104:H4, an hybrid pathotype of Shiga toxigenic and enteroaggregative E. coli, involved in a major foodborne outbreak in Germany in 2011, has not been detected in cattle feces. Serogroup O104 with H type other than H4 has been reported to cause human illnesses, but their prevalence and characteristics in cattle have not been reported. Our objectives were to determine the prevalence of E. coli O104 in feces of feedlot cattle, by culture and PCR detection methods, and characterize the isolated strains. Rectal fecal samples from a total of 757 cattle originating from 29 feedlots were collected at a Midwest commercial slaughter plant. Fecal samples, enriched in E. coli broth, were subjected to culture and PCR methods of detection. The culture method involved immunomagnetic separation with O104-specific beads and plating on a selective chromogenic medium, followed by serogroup confirmation of pooled colonies by PCR. If pooled colonies were positive for the wzxO104 gene, then colonies were tested individually to identify wzxO104-positive serogroup and associated genes of the hybrid strains. Extracted DNA from feces were also tested by a multiplex PCR to detect wzxO104-positive serogroup and associated major genes of the O104 hybrid pathotype. Because wzxO104 has been shown to be present in E. coli O8/O9/O9a, wzxO104-positive isolates and extracted DNA from fecal samples were also tested by a PCR targeting wbdDO8/O9/O9a, a gene specific for E. coli O8/O9/O9a serogroups. Model-adjusted prevalence estimates of E. coli O104 (positive for wzxO104 and negative for wbdDO8/O9/O9a) at the feedlot level were 5.7% and 21.2%, and at the sample level were 0.5% and 25.9% by culture and PCR, respectively. The McNemar's test indicated that there was a significant difference (P < 0.01) between the proportions of samples that tested positive for wzxO104 and samples that were positive for wzxO104, but negative for wbdDO8/O9/O9a by PCR and culture methods. A total of 143 isolates, positive for the wzxO104, were obtained in pure culture from 146 positive fecal samples. Ninety-two of the 143 isolates (64.3%) also tested positive for the wbdDO8/O9/O9a, indicating that only 51 (35.7%) isolates truly belonged to the O104 serogroup (positive for wzxO104 and negative for wbdDO8/O9/O9a). All 51 isolates tested negative for eae, and 16 tested positive for stx1 gene of the subtype 1c. Thirteen of the 16 stx1-positive O104 isolates were from one feedlot. The predominant serotype was O104:H7. Pulsed-field gel electrophoresis analysis indicated that stx1-positive O104:H7 isolates had 62.4% homology to the German outbreak strain and 67.9% to 77.5% homology to human diarrheagenic O104:H7 strains. The 13 isolates obtained from the same feedlot were of the same PFGE subtype with 100% Dice similarity. Although cattle do not harbor the O104:H4 pathotype, they do harbor and shed Shiga toxigenic O104 in the feces and the predominant serotype was O104:H7.

Occurrence of foodborne bacteria in Alberta feedlots.

PubMed

Van Donkersgoed, Joyce; Bohaychuk, Valerie; Besser, Thomas; Song, Xin-Ming; Wagner, Bruce; Hancock, Dale; Renter, David; Dargatz, David

2009-02-01

The occurrence of generic Escherichia coli, E. coli O157, Salmonella, and Campylobacter in cattle manure, beef carcasses, catch basin water, and soils receiving manure application was determined in 21 Alberta feedlots. In cattle manure, generic E. coli (98%, 2069/2100) and Campylobacter (76%, 1590/2100) were frequently detected; E. coli O157 (7%, 143/2100) and Salmonella (1%, 20/2100) were less frequently detected. Samples from beef carcasses in the cooler following Hazard Analysis Critical Control Point interventions yielded only 1 isolate each of generic E. coli and Campylobacter (1/1653) and no Salmonella (0/1653). Catch basin water specimens were positive for generic E. coli in both the spring (62%, 13/21) and the fall (52%, 11/21). Other bacteria were detected only in the spring water specimens, including E. coli O157 (29%, 6/21), Salmonella (5%, 1/21), and Campylobacter (52%, 11/21). Generic E. coli was frequently isolated from soil specimens (30%, 27/88), but E. coli O157 was not found in soil samples obtained in the spring and was only occasionally detected in the fall samples (9%, 3/32). Salmonella were occasionally found in the soil specimens collected in the spring (3%, 2/56), but not in the fall season (0/32). Campylobacter jejuni was frequent in cattle manure (66%, 1070/1623), but rare in carcass and environmental samples. E. coli O157 and Salmonella were rarely detected in cattle or the environment. Generic E. coli and Salmonella were rarely detected on carcasses.

Molecular Analysis of Escherichia coli from retail meats (2002-2004) from the United States National Antimicrobial Resistance Monitoring System.

PubMed

Johnson, James R; McCabe, James S; White, David G; Johnston, Brian; Kuskowski, Michael A; McDermott, Patrick

2009-07-15

The origins and virulence potential of meat product-associated Escherichia coli are undefined. Two hundred eighty-seven E. coli isolates (145 resistant and 142 susceptible to trimethoprim-sulfamethoxazole, nalidixic acid, and/or ceftiofur), recovered by the United States National Antimicrobial Monitoring System from retail beef, pork, chicken, and turkey products (from Oregon, Tennessee, Georgia, and Maryland, 2002-2004) underwent polymerase chain reaction testing for phylogenetic groupings and 59 virulence-associated genes. However analyzed, resistant and susceptible isolates differed minimally according to the assessed characteristics. In contrast, the 4 meat types differed greatly for multiple individual traits and aggregate virulence scores. Poultry isolates exhibited virulence genes associated with avian pathogenic E. coli; beef isolates exhibited traits associated with E. coli from diseased cattle. Overall, 20% of isolates qualified as extraintestinal pathogenic E. coli, with poultry isolates exhibiting significantly higher virulence scores than beef and pork isolates (P < .001). Within this systematically collected, geographically distributed sample of recent retail meat isolates, the carriage of extraintestinal pathogenic E. coli virulence genes in antimicrobial-resistant and antimicrobial-susceptible E. coli appeared similar, whereas isolates from different types of meat differed, consistent with on-farm acquisition of resistance within host species-specific E. coli populations. A substantial minority of meat-source E. coli (whether susceptible or resistant) may represent potential human pathogens.

Occurrence of plasmid-mediated quinolone resistance genes in Escherichia coli and Klebsiella spp. recovered from Corvus brachyrhynchos and Corvus corax roosting in Canada.

PubMed

Janecko, Nicol; Halova, Dana; Jamborova, Ivana; Papousek, Ivo; Masarikova, Martina; Dolejska, Monika; Literak, Ivan

2018-04-19

The spread of antimicrobial resistance from human activity derived sources to natural habitats implicates wildlife as potential vectors of antimicrobial resistance transfer. Wild birds, including corvid species can disseminate mobile genetic resistance determinants through feces. This study aimed to determine the occurrence of plasmid-mediated quinolone resistance (PMQR) genes in Escherichia coli and Klebsiella spp. isolates obtained from winter roosting sites of American crows (Corvus brachyrhynchos) and common ravens (Corvus corax) in Canada. Fecal swabs were collected at five roosting sites across Canada. Selective media isolation and multiplex PCR screening was utilized to identify PMQR genes followed by gene sequencing, PFGE and MLST to characterize isolates. Despite the low prevalence of E. coli containing PMQR (1.3%, 6/449), qnrS1, qnrB19, qnrC, oqxAB and aac(6')-Ib-cr genes were found in five sequence types (ST), including E. coli ST 131. Conversely, one isolate of Klebsiella pneumoniae contained the plasmid-mediated resistance gene qnrB19. Five different K. pneumoniae STs were identified, including two novel types. The occurrence of PMQR genes and STs of public health significance in E. coli and Klebsiella pneumoniae recovered from corvids gives further evidence of the anthropogenic derived dissemination of antimicrobial resistance determinants at the human activity-wildlife-environment interface. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Whole-genome sequence of Escherichia coli serotype O157:H7 strain B6914-ARS

USDA-ARS?s Scientific Manuscript database

Escherichia coli serotype O157:H7 strain B6914-MS1 is a Shiga toxin-deficient human fecal isolate obtained by the Centers for Disease Control and Prevention that has been used extensively in applied research studies. Here we report the genome sequence of strain B6914-ARS, a B6914-MS1 clone that has ...

Pyranose 2-oxidase from Phanerochaete chrysosporium : expression in E. coli and biochemical characterization

Treesearch

Ines Pisanelli; Magdalena Kujawa; Oliver Spadiut; Roman Kittl; Petr Halada; Jindrich Volc; Michael D. Mozuch; Philip Kersten; Dietmar Haltrich; Clemens Peterbauer

2009-01-01

The presented work reports the isolation and heterologous expression of the p2ox gene encoding the flavoprotein pyranose 2-oxidase (P2Ox) from the basidiomycete Phanerochaete chrysosporium. The p2ox cDNA was inserted into the bacterial expression vector pET21a(+) and successfully expressed in Escherichia coli. We obtained active, fully flavinylated recombinant P2Ox in...

Genetic diversity and antimicrobial resistance among isolates of Escherichia coli O157: H7 from feces and hides of super-shedders and low-shedding pen-mates in two commercial beef feedlots

PubMed Central

2012-01-01

Background Cattle shedding at least 104 CFU Escherichia coli O157:H7/g feces are described as super-shedders and have been shown to increase transmission of E. coli O157:H7 to other cattle in feedlots. This study investigated relationships among fecal isolates from super-shedders (n = 162), perineal hide swab isolates (PS) from super-shedders (n = 137) and fecal isolates from low-shedder (< 104 CFU/g feces) pen-mates (n = 496) using pulsed-field gel electrophoresis (PFGE). A subsample of these fecal isolates (n = 474) was tested for antimicrobial resistance. Isolates of E. coli O157:H7 were obtained from cattle in pens (avg. 181 head) at 2 commercial feedlots in southern Alberta with each steer sampled at entry to the feedlot and prior to slaughter. Results Only 1 steer maintained super-shedder status at both samplings, although approximately 30% of super-shedders in sampling 1 had low-shedder status at sampling 2. A total of 85 restriction endonuclease digestion clusters (REPC; 90% or greater similarity) and 86 unique isolates (< 90% similarity) were detected, with the predominant REPC (30% of isolates) being isolated from cattle in all feedlot pens, although it was not associated with shedding status (super- or low-shedder; P = 0.94). Only 2/21 super-shedders had fecal isolates in the same REPC at both samplings. Fecal and PS isolates from individual super-shedders generally belonged to different REPCs, although fecal isolates of E. coli O157:H7 from super- and low-shedders showed greater similarity (P < 0.001) than those from PS. For 77% of super-shedders, PFGE profiles of super-shedder fecal and PS isolates were distinct from all low-shedder fecal isolates collected in the same pen. A low level of antimicrobial resistance (3.7%) was detected and prevalence of antimicrobial resistance did not differ among super- and low-shedder isolates (P = 0.69), although all super-shedder isolates with antimicrobial resistance (n = 3) were resistant to multiple antimicrobials. Conclusions Super-shedders did not have increased antimicrobial resistance compared to low-shedder pen mates. Our data demonstrated that PFGE profiles of individual super-shedders varied over time and that only 1/162 steers remained a super-shedder at 2 samplings. In these two commercial feedlots, PFGE subtypes of E. coli O157:H7 from fecal isolates of super- and low-shedders were frequently different as were subtypes of fecal and perineal hide isolates from super-shedders. PMID:23014060

Comparison of CTX-M-14- and CTX-M-15-producing Escherichia coli and Klebsiella pneumoniae isolates from patients with bacteremia.

PubMed

Shin, Juyoun; Kim, Dae Hun; Ko, Kwan Soo

2011-07-01

Recently, CTX-M-15-producing Enterobacteriaceae has disseminated worldwide. To better understand the success of CTX-M-15-type extended-spectrum β-lactamase, we compared the CTX-M-15-producing Escherichia coli and Klebsiella pneumoniae isolates with CTX-M-14-producing E. coli and K. pneumoniae isolates that had been more prevalent before the recent increase of CTX-M-15 in Korea. Eighty-nine CTX-M-producing E. coli bloodstream infection isolates and 33 K. pneumoniae bloodstream infection isolates were collected in 2008 from nine hospitals in Korea. In vitro susceptibility testing and multilocus sequence typing were performed for all isolates. Phylogenetic groupings and distribution of virulence determinants and addiction systems were examined for only E. coli isolates. Among the 89 CTX-M-producing E. coli isolates, 54 isolates (60.7%) contained bla(CTx-M-15) and bla(CTx-M-14) was identified in 31 isolates (34.8%). Among 33 CTX-M-producing K. pneumoniae isolates, bla(CTx-M-14) and bla(CTx-M-15) were identified in 18 (54.5%) and 15 (45.5%) isolates, respectively. While CTX-M-14- and CTX-M-15-producing E. coli isolates displayed similar antimicrobial resistance rates, CTX-M-15-producing K. pneumoniae isolates showed significantly higher resistance rates of ciprofloxacin and piperacillin-tazobactam than CTX-M-14-producing isolates. ST131 and ST405 were the main clones in both CTX-M-14- and CTX-M-15-producing E. coli isolates. Although the frequency of virulence determinants was similar between two E. coli groups, ST131 and ST405 isolates producing CTX-M-15 showed higher frequency of determinants. In addition, CTX-M-15-producing E. coli isolates showed higher prevalence of addiction systems, particularly vagCD. ST405 showed the highest prevalence rates among main E. coli clones. In K. pneumoniae, ST15 and ST11, with high resistance rates, were the main clones of CTX-M-15-producing isolates, but no main clones was found among CTX-M-14-producing isolates because of extreme diversity. Rapid increase of CTX-M-15-producing E. coli isolates was due to certain clone with high frequency of virulence determinants and addiction systems. High antimicrobial resistance rates of CTX-M-15-producing K. pneumoniae isolates may contribute to their increase. Copyright © 2011 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

[BIOLOGICAL ACTIVITY OF ANTIMICROBIAL PEPTIDES FROM CHICKENS THROMBOCYTES].

PubMed

Sycheva, M V; Vasilchenko, A S; Rogozhin, E A; Pashkova, T M; Popova, L P; Kartashova, O L

2016-01-01

Isolation and study of biological activity of antimicrobial peptides from chickens thrombocytes. Peptides from chickens thrombocytes, obtained by reverse-phase high-performance liquid chromatography method with stepped and linear gradients of concentration increase of the organic solvent were used in the study. Their antimicrobial activity was determined by microtitration method in broth; mechanism of biological effect--by using fluorescent spectroscopy method with DNA-tropic dyes. Individual fractions of peptides were isolated from chickens thrombocytes, that possess antimicrobial activity against Staphylococcus aureus P209 and Escherichia coli K12. A disruption of integrity of barrier structures of microorganisms under the effect of thrombocyte antimicrobial peptides and predominance of cells with damaged membrane in the population of E. coli was established. The data obtained on antimicrobial activity and mechanism of bactericidal effect of the peptide fractions from chickens thrombocytes isolated for the first time expand the understanding of functional properties of chickens thrombocytes and open a perspective for their further study with the aim of use as antimicrobial means.

[Pathogenic activity modulation of Escherichia coli TL+ toxin with an isolated protein of Giardia intestinalis and a synthetic peptide].

PubMed

Jiménez-Cardoso, E; Eligio-García, L; Jiménez-Cardoso, J M; Angeles-Anguiano, E; Tobilla-Mercado, J M; Castañeda, G

2001-01-01

It is know that a protein from Giardia intestinalis works as a substrate for V. cholerae and Escherichia coli. The toxic activity of both activates protein G form intestinal mucosa with a pathogenic activity results. In the present study, the pathogenic activity of subunit A of Vibrio cholerae toxin (ADP-ribosyltranferase) using isolated fragments from: Giardia intestinalis and a synthetic peptide were used as modulators in vivo. Adult Neo Zealand males rabbits with ileal loop were prepared and different mixtures of heat labile enterotoxin obtained from Escherichia coli H10407 and ARF protein isolated by electrofocusing from Giardia intestinalis Portland I were inoculated in the loops. The toxin activity was evaluated by luminal liquid secretion and cyclic AMP concentration in tissues (each loop). ADP ribosyltranferase activity was modulated, due to a decreased of luminal secretion and cAMP in tissues. Such results were seen when synthetic peptide and subunit A from Vibrio cholerae were used. The ADP ribosyltranferase activity of heat labile Escherichia coli and Vibrio cholerae toxins were modified by in vitro and in vivo interaction with ARF protein, which modified pathogenic effect over rabbits intestinal epithelium.

[Characterization of Escherichia coli isolates derived from phylogenetic groups A and B1 causing extraintestinal infection].

PubMed

Moreno, Eva; Prats, Guillem; Planells, Irene; Planes, Ana M; Pérez, Teresa; Andreu, Antonia

2006-10-01

Escherichia coli isolates from the non-pathogenic phylogenetic groups A and B1 rarely cause extraintestinal infections. The aim of this study was to analyze 37 E. coli isolates pertaining to phylogenetic groups A and B1 and compare them with 37 E. coli isolates from group B2 and 31 from group D, which caused the same infections. Among 105 E. coli isolated from the urine of patients with cystitis and pyelonephritis and from the blood of patients with urinary-source and other-source bacteriemia, the E. coli phylogenetic groups, 15 virulence-associated genes, 7 O-antigens and fluoroquinolone resistance were analyzed. E. coli from groups A and B1 showed fewer virulence determinants (median 3.5) than E. coli from group B2 (8.6, P < 0.01) or D (5.3, P < .001); however, a subgroup containing 3 isolates from group A and 5 from B1 harbored 5 or more factors. E. coli from groups A/B1 were associated with resistance to fluoroquinolones (74%, P < .001), whereas E. coli from group B2 were associated with susceptibility to this antibiotic (76%, P = .003). E. coli from groups A/B1 were isolated significantly more frequently in patients with pyelonephritis or sepsis and local or general factors favoring infection, association not observed in patients with cystitis. Even though most of the E. coli isolates from phylogenetic groups A and B1 presented a low virulence potential, they were able to cause extraintestinal infections, particularly in compromised patients.

Evaluation of a Method Using Three Genomic Guided Escherichia coli Markers for Phylogenetic Typing of E. coli Isolates of Various Genetic Backgrounds

PubMed Central

Hamamoto, Kouta; Ueda, Shuhei; Yamamoto, Yoshimasa

2015-01-01

Genotyping and characterization of bacterial isolates are essential steps in the identification and control of antibiotic-resistant bacterial infections. Recently, one novel genotyping method using three genomic guided Escherichia coli markers (GIG-EM), dinG, tonB, and dipeptide permease (DPP), was reported. Because GIG-EM has not been fully evaluated using clinical isolates, we assessed this typing method with 72 E. coli collection of reference (ECOR) environmental E. coli reference strains and 63 E. coli isolates of various genetic backgrounds. In this study, we designated 768 bp of dinG, 745 bp of tonB, and 655 bp of DPP target sequences for use in the typing method. Concatenations of the processed marker sequences were used to draw GIG-EM phylogenetic trees. E. coli isolates with identical sequence types as identified by the conventional multilocus sequence typing (MLST) method were localized to the same branch of the GIG-EM phylogenetic tree. Sixteen clinical E. coli isolates were utilized as test isolates without prior characterization by conventional MLST and phylogenetic grouping before GIG-EM typing. Of these, 14 clinical isolates were assigned to a branch including only isolates of a pandemic clone, E. coli B2-ST131-O25b, and these results were confirmed by conventional typing methods. Our results suggested that the GIG-EM typing method and its application to phylogenetic trees might be useful tools for the molecular characterization and determination of the genetic relationships among E. coli isolates. PMID:25809972

Evaluation of a Method Using Three Genomic Guided Escherichia coli Markers for Phylogenetic Typing of E. coli Isolates of Various Genetic Backgrounds.

PubMed

Hamamoto, Kouta; Ueda, Shuhei; Yamamoto, Yoshimasa; Hirai, Itaru

2015-06-01

Genotyping and characterization of bacterial isolates are essential steps in the identification and control of antibiotic-resistant bacterial infections. Recently, one novel genotyping method using three genomic guided Escherichia coli markers (GIG-EM), dinG, tonB, and dipeptide permease (DPP), was reported. Because GIG-EM has not been fully evaluated using clinical isolates, we assessed this typing method with 72 E. coli collection of reference (ECOR) environmental E. coli reference strains and 63 E. coli isolates of various genetic backgrounds. In this study, we designated 768 bp of dinG, 745 bp of tonB, and 655 bp of DPP target sequences for use in the typing method. Concatenations of the processed marker sequences were used to draw GIG-EM phylogenetic trees. E. coli isolates with identical sequence types as identified by the conventional multilocus sequence typing (MLST) method were localized to the same branch of the GIG-EM phylogenetic tree. Sixteen clinical E. coli isolates were utilized as test isolates without prior characterization by conventional MLST and phylogenetic grouping before GIG-EM typing. Of these, 14 clinical isolates were assigned to a branch including only isolates of a pandemic clone, E. coli B2-ST131-O25b, and these results were confirmed by conventional typing methods. Our results suggested that the GIG-EM typing method and its application to phylogenetic trees might be useful tools for the molecular characterization and determination of the genetic relationships among E. coli isolates. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Isolation, Purification and Characterization of Antimicrobial Agent Antagonistic to Escherichia coli ATCC 10536 Produced by Bacillus pumilus SAFR-032 Isolated from the Soil of Unaizah, Al Qassim Province of Saudi Arabia.

PubMed

S Alanazi, Abdurrahman; Qureshi, Kamal Ahmad; Elhassan, Gamal Osman; I El-Agamy, Elsayed

Escherichia coli is one of the most common pathogenic bacteria, which cause urinary tract infections in infants as well as in adult human beings. Due to the emergence of antibiotic resistance in E. coli, there is a great demand of new antimicrobial agent for the treatment of infections caused by such E. coli. This study aims to isolate, identify and characterize the native soil-bacterial strains predominate in the soil of Unaizah city, which produce antimicrobial agent antagonistic to E. coli ATCC 10536, followed by isolation, purification and characterization of antimicrobial agent. Pour plate, spread plate and 16S rRNA sequence analysis methods were followed for the isolation and identification of soil bacteria. Ammonium sulphate and dialysis (MWCO-8 KD) methods were followed for the isolation and partial purification of antimicrobial agent from the cell free broths. The characterization of antimicrobial agent was carried out by determining the minimum inhibitory concentration and effects of temperature and pH on the antimicrobial stability. Out of the twenty five soil samples, only one soil-bacterial strain was found to produce antimicrobial agent antagonistic to E. coli ATCC 10536. The isolated soil bacterium was identified as Bacillus pumilus SAFR-032. The soil isolate was characterized and results suggest that 30°C temperature and pH 7.0 were the optimum growth parameters and soybean casein digest broth was the best fermentation medium, whereas the highest production of antimicrobial agent was at 35°C temperature, pH 7.0, shaking at 150-220 rpm and at 60th h of incubation. The maximum yield of antimicrobial agent was obtained at 60% of (NH 4) 2SO 4. The results of characterization of antimicrobial agent suggest that the maximum and minimum antimicrobial activities were at pH 3.0 and 8.0, respectively, whereas antimicrobial activity was unaffected by temperature. The antimicrobial agent was highly stable at varying range of temperature 50-120°C. Minimum inhibitory concentration of antimicrobial agent was found to be 64 μg mL -1. In conclusion, this study might be a great endeavor for the healthcare industry in order to treatment of different infections caused by E. coli and that warrants further investigations to fully standardized and establish the antimicrobial profile of effect(s) of this isolate.

Evaluation of Escherichia coli isolates from healthy chickens to determine their potential risk to poultry and human health.

PubMed

Stromberg, Zachary R; Johnson, James R; Fairbrother, John M; Kilbourne, Jacquelyn; Van Goor, Angelica; Curtiss, Roy; Mellata, Melha

2017-01-01

Extraintestinal pathogenic Escherichia coli (ExPEC) strains are important pathogens that cause diverse diseases in humans and poultry. Some E. coli isolates from chicken feces contain ExPEC-associated virulence genes, so appear potentially pathogenic; they conceivably could be transmitted to humans through handling and/or consumption of contaminated meat. However, the actual extraintestinal virulence potential of chicken-source fecal E. coli is poorly understood. Here, we assessed whether fecal E. coli isolates from healthy production chickens could cause diseases in a chicken model of avian colibacillosis and three rodent models of ExPEC-associated human infections. From 304 E. coli isolates from chicken fecal samples, 175 E. coli isolates were screened by PCR for virulence genes associated with human-source ExPEC or avian pathogenic E. coli (APEC), an ExPEC subset that causes extraintestinal infections in poultry. Selected isolates genetically identified as ExPEC and non-ExPEC isolates were assessed in vitro for virulence-associated phenotypes, and in vivo for disease-causing ability in animal models of colibacillosis, sepsis, meningitis, and urinary tract infection. Among the study isolates, 13% (40/304) were identified as ExPEC; the majority of these were classified as APEC and uropathogenic E. coli, but none as neonatal meningitis E. coli. Multiple chicken-source fecal ExPEC isolates resembled avian and human clinical ExPEC isolates in causing one or more ExPEC-associated illnesses in experimental animal infection models. Additionally, some isolates that were classified as non-ExPEC were able to cause ExPEC-associated illnesses in animal models, and thus future studies are needed to elucidate their mechanisms of virulence. These findings show that E. coli isolates from chicken feces contain ExPEC-associated genes, exhibit ExPEC-associated in vitro phenotypes, and can cause ExPEC-associated infections in animal models, and thus may pose a health threat to poultry and consumers.

Evaluation of Escherichia coli isolates from healthy chickens to determine their potential risk to poultry and human health

PubMed Central

Johnson, James R.; Fairbrother, John M.; Kilbourne, Jacquelyn; Van Goor, Angelica; Curtiss, Roy; Mellata, Melha

2017-01-01

Extraintestinal pathogenic Escherichia coli (ExPEC) strains are important pathogens that cause diverse diseases in humans and poultry. Some E. coli isolates from chicken feces contain ExPEC-associated virulence genes, so appear potentially pathogenic; they conceivably could be transmitted to humans through handling and/or consumption of contaminated meat. However, the actual extraintestinal virulence potential of chicken-source fecal E. coli is poorly understood. Here, we assessed whether fecal E. coli isolates from healthy production chickens could cause diseases in a chicken model of avian colibacillosis and three rodent models of ExPEC-associated human infections. From 304 E. coli isolates from chicken fecal samples, 175 E. coli isolates were screened by PCR for virulence genes associated with human-source ExPEC or avian pathogenic E. coli (APEC), an ExPEC subset that causes extraintestinal infections in poultry. Selected isolates genetically identified as ExPEC and non-ExPEC isolates were assessed in vitro for virulence-associated phenotypes, and in vivo for disease-causing ability in animal models of colibacillosis, sepsis, meningitis, and urinary tract infection. Among the study isolates, 13% (40/304) were identified as ExPEC; the majority of these were classified as APEC and uropathogenic E. coli, but none as neonatal meningitis E. coli. Multiple chicken-source fecal ExPEC isolates resembled avian and human clinical ExPEC isolates in causing one or more ExPEC-associated illnesses in experimental animal infection models. Additionally, some isolates that were classified as non-ExPEC were able to cause ExPEC-associated illnesses in animal models, and thus future studies are needed to elucidate their mechanisms of virulence. These findings show that E. coli isolates from chicken feces contain ExPEC-associated genes, exhibit ExPEC-associated in vitro phenotypes, and can cause ExPEC-associated infections in animal models, and thus may pose a health threat to poultry and consumers. PMID:28671990

Extended-Spectrum-β-Lactamase-Producing Enterobacteriaceae Isolated from Vegetables Imported from the Dominican Republic, India, Thailand, and Vietnam

PubMed Central

Zurfluh, Katrin; Nüesch-Inderbinen, Magdalena; Morach, Marina; Zihler Berner, Annina; Hächler, Herbert

2015-01-01

To examine to what extent fresh vegetables imported into Switzerland represent carriers of extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae, 169 samples of different types of fresh vegetables imported into Switzerland from the Dominican Republic, India, Thailand, and Vietnam were analyzed. Overall, 25.4% of the vegetable samples yielded one or more ESBL-producing Enterobacteriaceae, 78.3% of which were multidrug resistant. Sixty isolates were obtained: Escherichia coli, 26; Klebsiella pneumoniae, 26; Enterobacter cloacae, 6; Enterobacter aerogenes, 1; and Cronobacter sakazakii, 1. We found 29 isolates producing CTX-M-15, 8 producing CTX-M-14, 7 producing CTX-M-55, 3 producing CTX-M-65, 1 each producing CTX-M-1, CTX-M-3, CTX-M-27, and CTX-M-63, 5 producing SHV-2, 3 producing SHV-12, and 1 producing SHV-2a. Four of the E. coli isolates belonged to epidemiologically important clones: CTX-M-15-producing B2:ST131 (1 isolate), D:ST405 (1 isolate), and D:ST38 (2 isolates). One of the D:ST38 isolates belonged to the extraintestinal enteroaggregative E. coli (EAEC) D:ST38 lineage. Two of the K. pneumoniae isolates belonged to the epidemic clones sequence type 15 (ST15) and ST147. The occurrence of antibiotic-resistant pathogenic and commensal Enterobacteriaceae in imported agricultural foodstuffs constitutes a source of ESBL genes and a concern for food safety. PMID:25724954

Efficacy of UV light treatment for the microbiological decontamination of chicken, associated packaging, and contact surfaces.

PubMed

Haughton, P N; Lyng, J G; Cronin, D A; Morgan, D J; Fanning, S; Whyte, P

2011-04-01

UV light was investigated for the decontamination of raw chicken, associated packaging, and contact surfaces. The UV susceptibilities of a number of Campylobacter isolates (seven Campylobacter jejuni isolates and three Campylobacter coli isolates), Escherichia coli ATCC 25922, and Salmonella enterica serovar Enteritidis ATCC 10376 in liquid media were also investigated. From an initial level of 7 log CFU/ml, no viable Campylobacter cells were detected following exposure to the most intense UV dose (0.192 J/cm(2)) in liquid media (skim milk subjected to ultrahigh-temperature treatment and diluted 1:4 with maximum recovery diluent). Maximum reductions of 4.8 and 6.2 log CFU/ml were achieved for E. coli and serovar Enteritidis, respectively, in liquid media. Considerable differences in susceptibilities were found between the Campylobacter isolates examined, with variations of up to 4 log CFU/ml being observed. UV treatment of raw chicken fillet (0.192 J/cm(2)) reduced C. jejuni, E. coli, serovar Enteritidis, total viable counts, and Enterobacteriaceae by 0.76, 0.98, 1.34, 1.76, and 1.29 log CFU/g, respectively. Following UV treatment of packaging and surface materials, reductions of up to 3.97, 4.50, and 4.20 log CFU/cm(2) were obtained for C. jejuni, E. coli, and serovar Enteritidis, respectively (P < 0.05). Overall, the color of UV-treated chicken was not significantly affected (P ≥ 0.05). The findings of this study indicate that Campylobacter is susceptible to UV technology and that differences in sensitivities exist between investigated isolates. Overall, UV could be used for improving the microbiological quality of raw chicken and for decontaminating associated packaging and surface materials.

[Prevalence of ESBL-positive enterobacteriaceae in large moravian hospitals (Czech Republic)].

PubMed

Kolář, Milan; Chromá, Magdaléna; Hricová, Kristýna; Husičková, Vendula; Lovečková, Yvona; Chmelařová, Eva; Bartoníková, Nataša; Rybníkářová, Petra

2010-10-01

bacterial infections have become an important issue in current medicine. Recently, their frequency and severity have significantly increased as a result of the rising number of resistant bacteria. One of important mechanisms of resistance is production of broad-spectrum beta-lactamases, namely the ESBL type. The study aimed at determining the frequency of ESBL-positive Enterobacteriaceae in three large hospitals in Moravia, the eastern part of the Czech Republic. enterobacteriaceae were isolated from clinical material obtained from patients hospitalized in the University Hospital Olomouc, Teaching Hospital Ostrava and Bata Regional Hospital Zlín throughout 2009. Standard microbiology techniques were used for identification. The production of ESBLs was determined by the modified Double-Disk Synergy Test. ESBL-positive isolates of Escherichia coli from ICU patients were subjected to basic genetic analysis. during the study period, a total of 12,922 strains from the Enterobacteriaceae family were detected. The ESBL phenotype was found in 907 cases, i.e. 7 % of all isolates. The most prevalent species of ESBL-producing Enterobacteriaceae were Klebsiella pneumoniae, Klebsiella oxytoca and Escherichia coli. A comparison of general wards and ICUs revealed a higher percentage of ESBL-positive strains of Klebsiella pneumoniae and a lower proportion of ESBL-positive Escherichia coli isolates in intensive care patients. When assessing the patients' clinical material, ESBL-producing strains were most frequently detected in urine. Genetic analysis of ESBL-positive Escherichia coli strains from ICU patients revealed the CTX-M type of ESBL production in most isolates.

Escherichia coli, Salmonella, and Mycobacterium avium subsp. paratuberculosis in wild European starlings at a Kansas cattle feedlot.

PubMed

Gaukler, Shannon M; Linz, George M; Sherwood, Julie S; Dyer, Neil W; Bleier, William J; Wannemuehler, Yvonne M; Nolan, Lisa K; Logue, Catherine M

2009-12-01

The prevalence of Escherichia coli, Salmonella spp., and Mycobacterium avium subsp. paratuberculosis isolated from the feces of wild European starlings (Sturnus vulgaris) humanely trapped at a feedlot in central Kansas was assessed. All E. coli and Salmonella isolates recovered were tested for antimicrobial susceptibility using National Antimicrobial Resistance Monitoring System panels and the E. coli isolates were classified as to their content of genes associated with pathogenic E. coli of birds and cattle, including cvaC, iroN2, ompTp, hlyF2, eitC, iss, iutA, ireA, papC, stxI, stxII, sta, K99, F41, and eae. Escherichia coli O157:H7 and Mycobacterium avium subsp. paratuberculosis were not detected and Salmonella was isolated from only three samples, two of which displayed antimicrobial resistance. Approximately half of the E. coli isolates were resistant to antimicrobial agents with 96% showing resistance to tetracycline. Only one isolate was positive for a single gene associated with bovine pathogenic E. coli. An interesting finding of this study was that 5% of the E. coli isolates tested met the criteria established for identification as avian pathogenic E. coli (APEC). Thus these findings suggest that starlings are not a significant source of Salmonella spp., Mycobacterium avium subsp. paratuberculosis, E. coli O157, or other shiga toxin-producing E. coli in this feedlot. However, they may have the potential to spread APEC, an important pathogen of poultry and a potential pathogen to human beings.

Isolating Escherichia coli strains for recombinant protein production.

PubMed

Schlegel, Susan; Genevaux, Pierre; de Gier, Jan-Willem

2017-03-01

Escherichia coli has been widely used for the production of recombinant proteins. To improve protein production yields in E. coli, directed engineering approaches have been commonly used. However, there are only few reported examples of the isolation of E. coli protein production strains using evolutionary approaches. Here, we first give an introduction to bacterial evolution and mutagenesis to set the stage for discussing how so far selection- and screening-based approaches have been used to isolate E. coli protein production strains. Finally, we discuss how evolutionary approaches may be used in the future to isolate E. coli strains with improved protein production characteristics.

Prevalence and Characterization of β-Lactamases Genes and Class 1 Integrons in Multidrug-Resistant Escherichia coli Isolates from Chicken Meat in Korea.

PubMed

Seo, Kwang Won; Lee, Young Ju

2018-06-21

Antimicrobial resistance has become a serious public health threat throughout the world, and therapeutic options for several infectious diseases are currently limited by the presence of multidrug-resistant (MDR) bacteria. This study was designed to examine the drug resistance patterns, the prevalence of the β-lactamases, and class 1 integrons in MDR Escherichia coli isolates from chicken meat in Korea. Among 200 chicken meat samples, 101 isolates were observed to be positive for E. coli, of which 57 were identified as MDR E. coli. Among 57 MDR E. coli isolates, the prevalence of bla gene, bla CTX-M-1 , bla CTX-M-14 , and bla TEM-1 , were identified in 2, 4, and 16 E. coli strains, respectively; only 1 E. coli strain had both, bla TEM-1 and bla CTX-M-1 genes. Twenty-one of the 57 MDR E. coli isolates also carried class 1 integrons, and 5 different gene cassette arrangements were found in 14 of the 21 class 1 integron-positive isolates. The β-lactamase-producing E. coli and integron-positive E. coli had significantly higher resistance to 16 antimicrobial drugs than the non-β-lactamase-producing E. coli and the integron-negative E. coli (p < 0.05). Our findings suggest that β-lactamase and class 1 integrons are widely distributed in E. coli isolates from chicken meat, and directly contribute to resistance to diverse antimicrobial agents. Therefore, continuous investigation of integron gene cassette arrays will provide useful information regarding antimicrobial resistance mechanisms.

Prevalence of Class D Carbapenemases among Extended-Spectrum β-Lactamases Producing Escherichia coli Isolates from Educational Hospitals in Shahrekord

PubMed Central

Damavandi, Mohammad-Sadegh; Latif Pour, Mohammad

2016-01-01

Introduction Extended-spectrum β-lactamases (ESBLs) are a set of plasmid-borne, various and quickly evolving enzymes that are a main therapeutic issue now-a-days for inpatient and outpatient treatment. Aim The aim of this study was to determine multi-drug resistance (MDR) and ESBLs producing E. coli strains, prevalence of class D Carbapenemases among ESBLs producing Escherichia coli isolates from educational hospitals in Shahrekord, Iran. Materials and Methods Uropathogenic Escherichia coli strains were isolated from patients with Urinary Tract Infections (UTIs). The agar disc diffusion test was used to characterize the antimicrobial sensitivity of the E. coli isolates. The ESBL positive strains were identified by phenotypic double-disk synergy test, by third-generation cephalosporin in combination with or without clavulanic acid. Multiplex PCR was carried out for detection of the three families of OXA-type carbapenamases including OXA-23, OXA-24, and OXA-48 in E. coli strains. Results All bacterial isolates were susceptible to meropenem. Ninety isolates produced ESBL, 55 E. coli isolates from inpatients, and 35 isolates from outpatients, with a significant association (p< 0.05). The prevalence of OXA-23, OXA-24, and OXA-48 in the ESBLs producing isolates was respectively 21%, 18%, and 11% for inpatients, and 10%, 8%, and 6% for outpatients. Conclusion ESBL-producing E. coli isolates are also a major threat in the clinical setting. The findings of this study indicated the high occurrence of ESBLs and multiple antibiotic resistance in E. coli isolates. PMID:27462579

Regional Dissemination of a Trimethoprim-Resistance Gene Cassette via a Successful Transposable Element

PubMed Central

Opintan, Japheth A.; Bishar, Rima A.; Aboderin, A. Oladipo; Newman, Mercy J.; Lamikanra, Adebayo; Okeke, Iruka N.

2012-01-01

Background Antimicrobial resistance is a growing international problem. We observed a 50% increase in the prevalence of trimethoprim resistance among fecal Escherichia coli from healthy Nigerian students between 1998 and 2005, a trend to increase that continued in 2009. Methods and Findings A PCR-based screen revealed that 131 (43.1%) of isolates obtained in Nigeria in 2005 and 2009 carried integron-borne dfrA cassettes. In the case of 67 (51.1%) of these isolates, the cassette was a class 1-integron-borne dfrA7 gene, which has been reported at high prevalence from E. coli isolates from other parts of Africa. Complete sequencing of a 27 Kb dfrA7-bearing plasmid from one isolate located the dfrA7 gene within a Tn21-type transposon. The transposon also contained an IS26-derived bla/sul/str element, encoding resistance to β-lactams, sulphonamides and streptomycin, and mercury resistance genes. Although the plasmid backbone was only found in 12 (5.8%) of trimethoprim-resistant isolates, dfrA7 and other transposon-borne genes were detected in 14 (16.3%) and 32 (26.3%) of trimethoprim resistant isolates collected in Nigeria in 2005 and 2009, respectively. Additionally, 37 (19.3%) of trimethoprim-resistant E. coli isolates collected between 2006 and 2008 from Ghana were positive for the dfrA7 and a transposon marker, but only 4 (2.1%) harbored the plasmid backbone. Conclusions Our data point to transposition as a principal mechanism for disseminating dfrA7 among E. coli from Nigeria and Ghana. On-going intensive use of the affordable broad-spectrum antibacterials is likely to promote selective success of a highly prevalent transposable element in West Africa. PMID:22666464

Colonization of Enteroaggregative Escherichia coli and Shiga toxin-producing Escherichia coli in chickens and humans in southern Vietnam.

PubMed

Trung, Nguyen Vinh; Nhung, Hoang Ngoc; Carrique-Mas, Juan J; Mai, Ho Huynh; Tuyen, Ha Thanh; Campbell, James; Nhung, Nguyen Thi; Van Minh, Pham; Wagenaar, Jaap A; Mai, Nguyen Thi Nhu; Hieu, Thai Quoc; Schultsz, Constance; Hoa, Ngo Thi

2016-09-09

Enteroaggregative (EAEC) and Shiga-toxin producing Escherichia coli (STEC) are a major cause of diarrhea worldwide. E. coli carrying both virulence factors characteristic for EAEC and STEC and producing extended-spectrum beta-lactamase caused severe and protracted disease during an outbreak of E. coli O104:H4 in Europe in 2011. We assessed the opportunities for E. coli carrying the aggR and stx genes to emerge in 'backyard' farms in south-east Asia. Faecal samples collected from 204 chicken farms; 204 farmers and 306 age- and gender-matched individuals not exposed to poultry farming were plated on MacConkey agar plates with and without antimicrobials being supplemented. Sweep samples obtained from MacConkey agar plates without supplemented antimicrobials were screened by multiplex PCR for the detection of the stx1, stx2 and aggR genes. One chicken farm sample each (0.5 %) contained the stx1 and the aggR gene. Eleven (2.4 %) human faecal samples contained the stx1 gene, 2 samples (0.4 %) contained stx2 gene, and 31 (6.8 %) contained the aggR gene. From 46 PCR-positive samples, 205 E. coli isolates were tested for the presence of stx1, stx2, aggR, wzx O104 and fliC H4 genes. None of the isolates simultaneously contained the four genetic markers associated with E. coli O104:H4 epidemic strain (aggR, stx2, wzx O104 and fliC H4 ). Of 34 EAEC, 64.7 % were resistant to 3(rd)-generation cephalosporins. These results indicate that in southern Vietnam, the human population is a more likely reservoir of aggR and stx gene carrying E. coli than the chicken population. However, conditions for transmission of isolates and/or genes between human and animal reservoirs resulting in the emergence of highly virulent E. coli strains are still favorable, given the nature of'backyard' farms in Vietnam.

Prevalence of Escherichia coli sequence type 131 and its H30 subclone among E. coli isolates in a French hospital.

PubMed

Lafolie, Jeremy; Nicolas-Chanoine, Marie-Hélène; Grenouillet, Frédéric; Hocquet, Didier; Bertrand, Xavier

2014-11-01

The prevalence of Escherichia coli sequence type 131 (ST131) and its subclone H30 was assessed among a collection of 490 E. coli isolated in 2013 in a French university hospital. The prevalence of ST131 was 4% among bloodstream isolates (regardless of antimicrobial resistance) and 17.2% among extended-spectrum β-lactamase (ESBL)-producing isolates. Although a much lower prevalence of ST131 was found among bloodstream E. coli isolates compared with other countries, a large predominance of H30 subclone within ST131 was confirmed. It was also confirmed that, among ESBL-producing E. coli, ST131 isolates were more frequently resistant to amoxicillin/clavulanic acid, ceftazidime, fluoroquinolones and aminoglycosides than non-ST131 isolates. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

E. coli Surface Properties Differ between Stream Water and Sediment Environments.

PubMed

Liang, Xiao; Liao, Chunyu; Thompson, Michael L; Soupir, Michelle L; Jarboe, Laura R; Dixon, Philip M

2016-01-01

The importance of E. coli as an indicator organism in fresh water has led to numerous studies focusing on cell properties and transport behavior. However, previous studies have been unable to assess if differences in E. coli cell surface properties and genomic variation are associated with different environmental habitats. In this study, we investigated the variation in characteristics of E. coli obtained from stream water and stream bottom sediments. Cell properties were measured for 77 genomically different E. coli strains (44 strains isolated from sediments and 33 strains isolated from water) under common stream conditions in the Upper Midwestern United States: pH 8.0, ionic strength 10 mM and 22°C. Measured cell properties include hydrophobicity, zeta potential, net charge, total acidity, and extracellular polymeric substance (EPS) composition. Our results indicate that stream sediment E. coli had significantly greater hydrophobicity, greater EPS protein content and EPS sugar content, less negative net charge, and higher point of zero charge than stream water E. coli . A significant positive correlation was observed between hydrophobicity and EPS protein for stream sediment E. coli but not for stream water E. coli . Additionally, E. coli surviving in the same habitat tended to have significantly larger (GTG) 5 genome similarity. After accounting for the intrinsic impact from the genome, environmental habitat was determined to be a factor influencing some cell surface properties, such as hydrophobicity. The diversity of cell properties and its resulting impact on particle interactions should be considered for environmental fate and transport modeling of aquatic indicator organisms such as E. coli .

Prevalence and Antibiogram Profiling of Escherichia coli Pathotypes Isolated from the Kat River and the Fort Beaufort Abstraction Water

PubMed Central

Nontongana, Nolonwabo; Sibanda, Timothy; Ngwenya, Elvis; Okoh, Anthony I.

2014-01-01

Escherichia coli is a widespread bacterium encompassing a variety of strains, ranging from highly pathogenic strains, causing worldwide outbreaks of severe diseases to avirulent, well characterized safe laboratory strains. This study evaluated the prevalence and antibiogram profiles of E. coli pathotypes isolated from the Kat River and Fort Beaufort abstraction water. A total of 171 out of 278 confirmed E. coli isolates were positive for at least one pathogenic determinant and these included enteropathogenic E. coli (6%), enterotoxigenic E. coli (47%), uropathogenic E. coli (2%), neonatal meningitis E. coli (5%), diffusely adherent E. coli (1%) and enterohaemorrhagic E. coli (1%). Interestingly, enteroinvasive and enteroaggregative E. coli were not detected. The phenotypic antibiogram profiles of the isolates revealed that all were resistant to penicillin G, while 98% and 38% of the pathotypes were resistant to ampicillin and trimethoprim-sulphamethoxazole, respectively. About 8% of the isolates were resistant to streptomycin. More than half of the isolates exhibited multiple antibiotic resistance with 44% being resistant to three antibiotics and 8% resistant to four antibiotics. We conclude that the Kat River is a reservoir of potentially virulent antibiotic resistant E. coli strains that can cause serious health risks to humans who drink raw water from this river, or in the case that consumption of treated drinking water coincides with failed drinking water processes. PMID:25119699

Evaluation of Escherichia coli biotype 1 as a surrogate for Escherichia coli O157:H7 for cooking, fermentation, freezing, and refrigerated storage in meat processes.

PubMed

Keeling, Carisa; Niebuhr, Steven E; Acuff, Gary R; Dickson, James S

2009-04-01

Five Escherichia coli biotype I isolates were compared with E. coli O157:H7 under four common meat processing conditions. The processes that were evaluated were freezing, refrigerating, fermentation, and thermal inactivation. For each study, at least one surrogate organism was not statistically different when compared with E. coli O157:H7. However, the four studies did not consistently show the same isolate as having this agreement. The three studies that involved temperature as a method of controlling or reducing the E. coli population all had at least one possible surrogate in common. In the fermentation study, only one isolate (BAA-1429) showed no statistical difference when compared with E. coli O157:H7. However, the population reductions that were observed indicated the isolates BAA-1427 and BAA-1431 would overestimate the surviving E. coli O157:H7 population in a fermented summer sausage. When all of the data from all of the surrogates were examined, it was found that isolates BAA-1427, BAA-1429, and BAA-1430 would be good surrogates for all four of the processes that were examined in this study. There was no statistical difference noted between these three isolates and E. coli O157:H7 in the refrigeration study. These isolates resulted in smaller population reductions than did E. coli O157:H7 in the frozen, fermentation, and thermal inactivation studies. This would indicate that these isolates would overpredict the E. coli O157:H7 population in these three instances. This overprediction results in an additional margin of safety when using E. coli biotype 1 as a surrogate.

Endoscopic retrograde cholangiopancreatography-associated AmpC Escherichia coli outbreak.

PubMed

Wendorf, Kristen A; Kay, Meagan; Baliga, Christopher; Weissman, Scott J; Gluck, Michael; Verma, Punam; D'Angeli, Marisa; Swoveland, Jennifer; Kang, Mi-Gyeong; Eckmann, Kaye; Ross, Andrew S; Duchin, Jeffrey

2015-06-01

We identified an outbreak of AmpC-producing Escherichia coli infections resistant to third-generation cephalosporins and carbapenems (CR) among 7 patients who had undergone endoscopic retrograde cholangiopancreatography at hospital A during November 2012-August 2013. Gene sequencing revealed a shared novel mutation in a bla CMY gene and a distinctive fumC/ fimH typing profile. To determine the extent and epidemiologic characteristics of the outbreak, identify potential sources of transmission, design and implement infection control measures, and determine the association between the CR E. coli and AmpC E. coli circulating at hospital A. We reviewed laboratory, medical, and endoscopy reports, and endoscope reprocessing procedures. We obtained cultures from endoscopes after reprocessing as well as environmental samples and conducted pulsed-field gel electrophoresis and gene sequencing on phenotypic AmpC isolates from patients and endoscopes. Cases were those infected with phenotypic AmpC isolates (both carbapenem-susceptible and CR) and identical bla CMY-2, fumC, and fimH alleles or related pulsed-field gel electrophoresis patterns. Thirty-five of 49 AmpC E. coli tested met the case definition, including all CR isolates. All cases had complicated biliary disease and had undergone at least 1 endoscopic retrograde cholangiopancreatography at hospital A. Mortality at 30 days was 16% for all patients and 56% for CR patients. Two of 8 reprocessed endoscopic retrograde cholangiopancreatography scopes harbored AmpC that matched case isolates by pulsed-field gel electrophoresis. Environmental cultures were negative. No breaches in infection control were identified. Endoscopic reprocessing exceeded manufacturer's recommended cleaning guidelines. Recommended reprocessing guidelines are not sufficient.

Occurrence and molecular characteristics of antimicrobial resistance of Escherichia coli from broilers, pigs and meat products in Thailand and Cambodia provinces.

PubMed

Trongjit, Suthathip; Angkittitrakul, Sunpetch; Chuanchuen, Rungtip

2016-09-01

Nine hundred and forty-one samples were collected in Sa Keao, Thailand (n = 554) and Banteay Meanchey, Cambodia (n = 387) from July 2014 to January 2015. A total of 667 Escherichia coli isolates (381 isolates from Sa Keao and 286 isolates from Banteay Meanchey) were obtained and examined for antimicrobial susceptibility, class 1 integrons, ESBL genes and horizontal transfer of resistance determinants. Prevalence of E. coli in pig and broiler carcass samples from slaughterhouses and fresh markets was 36-85% in Sa Keao and 11-69% in Banteay Meanchey. The majority of these isolates were multidrug resistant (75.3%). Class 1 integrons were common in both Thai (47%) and Cambodian (62%) isolates, of which four resistance gene cassette arrays including aadA1, dfrA1-aadA1, dfrA12-aadA2 and aadA2-linF were identified. Class 1 integrons in two broiler isolates from Sa Keao (dfrA12-aadA2) and one broiler isolate from Banteay Meanchey (dfrA1-aadA1) were horizontally transferable. Sixteen isolates were confirmed to be ESBL-producing strains with ESBL gene blaCTX-M-15 , broad spectrum β-lactamase gene blaTEM-1 and the AmpC gene blaCMY-2 being detected. The blaTEM-1 gene was most prevalent and located on a conjugative plasmid. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

A fifteen month study of Escherichia coli O157:H7 in a dairy herd.

PubMed Central

Mechie, S. C.; Chapman, P. A.; Siddons, C. A.

1997-01-01

A dairy herd associated with Escherichia coli O157 infection in humans was studied for the 15 months following the outbreak to examine seasonal, age and management factors affecting faecal excretion of the organism and to determine the mode and frequency of milk contamination with the organism. Between May 1993 and July 1994, 28 visits were made to the farm to collect a total of 3593 rectal swabs from cows, heifers and calves and 329 milk samples. E. coli O157:H7 was isolated from 153 (4.3%) of 3593 bovine rectal swabs. The maximum prevalence at any one visit was 14% in lactating cows, 40% in non-lactating cows, 56% in calves and 68% in heifers. The prevalence in lactating cows, which was significantly lower than in the other groups, peaked during May-July 1993 and again briefly after the cattle were housed during November 1993 and then again during May 1994. Excretion rates of E. coli O157:H7 in lactating cows were highest during the first month after calving, falling during lactation and rising to another peak at 7 months postpartum. Between November 1993 and May 1994 there was no evidence of excretion in any group. Eighty-seven (74%) of the animals which excreted E. coli O157:H7 did so on only one occasion but 23 (32%) of 73 cows and heifers and 7 (16%) of 44 calves which excreted the organism did so on more than one occasion. E. coli O157:H7 was not isolated from milk taken from the bulk tank but it was isolated from individual milk samples (one milk jar and one fore-milk) from two animals previously shown to be faecal excretors of the organism. All isolates of E. coli O157:H7 obtained were of the same phage type, toxin genotype and plasmid profile. PMID:9042031

Zoonotic Potential of Escherichia coli Isolates from Retail Chicken Meat Products and Eggs

PubMed Central

Mitchell, Natalie M.; Johnson, James R.; Johnston, Brian; Curtiss, Roy

2014-01-01

Chicken products are suspected as a source of extraintestinal pathogenic Escherichia coli (ExPEC), which causes diseases in humans. The zoonotic risk to humans from chicken-source E. coli is not fully elucidated. To clarify the zoonotic risk posed by ExPEC in chicken products and to fill existing knowledge gaps regarding ExPEC zoonosis, we evaluated the prevalence of ExPEC on shell eggs and compared virulence-associated phenotypes between ExPEC and non-ExPEC isolates from both chicken meat and eggs. The prevalence of ExPEC among egg-source isolates was low, i.e., 5/108 (4.7%). Based on combined genotypic and phenotypic screening results, multiple human and avian pathotypes were represented among the chicken-source ExPEC isolates, including avian-pathogenic E. coli (APEC), uropathogenic E. coli (UPEC), neonatal meningitis E. coli (NMEC), and sepsis-associated E. coli (SEPEC), as well as an undefined ExPEC group, which included isolates with fewer virulence factors than the APEC, UPEC, and NMEC isolates. These findings document a substantial prevalence of human-pathogenic ExPEC-associated genes and phenotypes among E. coli isolates from retail chicken products and identify key virulence traits that could be used for screening. PMID:25480753

Genome sequences of thirty Escherichia coli O157:H7 isolates recovered from a single dairy farm and its associated off-site heifer raising facility

USDA-ARS?s Scientific Manuscript database

Cattle are the primary reservoir of Escherichia coli O157:H7, the most frequently isolated serotype of enterohemorrhagic E. coli infections among humans in North America. To evaluate the diversity of E. coli O157:H7 isolates within a single dairy herd the genomes of 30 isolates collected over a 7-ye...

Association between antimicrobial resistance in Escherichia coli isolates from food animals and blood stream isolates from humans in Europe: an ecological study.

PubMed

Vieira, Antonio R; Collignon, Peter; Aarestrup, Frank M; McEwen, Scott A; Hendriksen, Rene S; Hald, Tine; Wegener, Henrik C

2011-12-01

In addition to medical antimicrobial usage, the use of antimicrobials in food animals contributes to the occurrence of resistance among some bacterial species isolated from infections in humans. Recently, several studies have indicated that a large proportion of Escherichia coli causing infections in humans, especially those resistant to antimicrobials, have an animal origin. We analyzed the correlation between the prevalence of antimicrobial resistance in E. coli isolates from blood stream infections in humans and in E. coli isolates from poultry, pigs, and cattle between 2005 and 2008 for 11 countries, using available surveillance data. We also assessed the correlation between human antimicrobial usage and the occurrence of resistance in E. coli isolates from blood stream infections. Strong and significant correlations between prevalences of resistance to ampicillin (r=0.94), aminoglycosides (r=0.72), third-generation cephalosporins (r=0.76), and fluoroquinolones (r=0.68) were observed for human and poultry E. coli isolates. Similar significant correlations were observed for ampicillin (r=0.91), aminoglycosides (r=0.73), and fluoroquinolone resistance (r=0.74) in pig and human isolates. In cattle isolates, only ampicillin resistance (r=0.72) was significantly correlated to human isolates. When usage of antimicrobials in humans was analyzed with antimicrobial resistance among human isolates, only correlations between fluoroquinolones (r=0.90) and third-generation cephalosporins (r=0.75) were significant. Resistance in E. coli isolates from food animals (especially poultry and pigs) was highly correlated with resistance in isolates from humans. This supports the hypothesis that a large proportion of resistant E. coli isolates causing blood stream infections in people may be derived from food sources.

Multidrug-Resistant and Extended Spectrum Beta-Lactamase-Producing Escherichia coli in Dutch Surface Water and Wastewater

PubMed Central

Blaak, Hetty; Lynch, Gretta; Italiaander, Ronald; Hamidjaja, Raditijo A.; Schets, Franciska M.; de Roda Husman, Ana Maria

2015-01-01

Objective The goal of the current study was to gain insight into the prevalence and concentrations of antimicrobial resistant (AMR) Escherichia coli in Dutch surface water, and to explore the role of wastewater as AMR contamination source. Methods The prevalence of AMR E. coli was determined in 113 surface water samples obtained from 30 different water bodies, and in 33 wastewater samples obtained at five health care institutions (HCIs), seven municipal wastewater treatment plants (mWWTPs), and an airport WWTP. Overall, 846 surface water and 313 wastewater E. coli isolates were analysed with respect to susceptibility to eight antimicrobials (representing seven different classes): ampicillin, cefotaxime, tetracycline, ciprofloxacin, streptomycin, sulfamethoxazole, trimethoprim, and chloramphenicol. Results Among surface water isolates, 26% were resistant to at least one class of antimicrobials, and 11% were multidrug-resistant (MDR). In wastewater, the proportions of AMR/MDR E. coli were 76%/62% at HCIs, 69%/19% at the airport WWTP, and 37%/27% and 31%/20% in mWWTP influents and effluents, respectively. Median concentrations of MDR E. coli were 2.2×102, 4.0×104, 1.8×107, and 4.1×107 cfu/l in surface water, WWTP effluents, WWTP influents and HCI wastewater, respectively. The different resistance types occurred with similar frequencies among E. coli from surface water and E. coli from municipal wastewater. By contrast, among E. coli from HCI wastewater, resistance to cefotaxime and resistance to ciprofloxacin were significantly overrepresented compared to E. coli from municipal wastewater and surface water. Most cefotaxime-resistant E. coliisolates produced ESBL. In two of the mWWTP, ESBL-producing variants were detected that were identical with respect to phylogenetic group, sequence type, AMR-profile, and ESBL-genotype to variants from HCI wastewater discharged onto the same sewer and sampled on the same day (A1/ST23/CTX-M-1, B23/ST131/CTX-M-15, D2/ST405/CTX-M-15). Conclusion In conclusion, our data show that MDR E. coli are omnipresent in Dutch surface water, and indicate that municipal wastewater significantly contributes to this occurrence. PMID:26030904

Distinct inflammatory and cytopathic characteristics of Escherichia coli isolates from inflammatory bowel disease patients.

PubMed

Jensen, Stina Rikke; Mirsepasi-Lauridsen, Hengameh Chloé; Thysen, Anna Hammerich; Brynskov, Jørn; Krogfelt, Karen A; Petersen, Andreas Munk; Pedersen, Anders Elm; Brix, Susanne

2015-12-01

Escherichia coli (E. coli) may be implicated in the pathogenesis of inflammatory bowel disease (IBD), as implied from a higher prevalence of mucosa-associated E. coli in the gut of IBD-affected individuals. However, it is unclear whether different non-diarrheagenic E. coli spp. segregate from each other in their ability to promote intestinal inflammation. Herein we compared the inflammation-inducing properties of non-diarrheagenic LF82, 691-04A, E. coli Nissle 1917 (ECN) and eleven new intestinal isolates from different locations in five IBD patients and one healthy control. Viable E. coli were cultured with human monocyte-derived dendritic cells (moDCs) and monolayers of intestinal epithelial cells (IECs), followed by analysis of secreted cytokines, intracellular levels of reactive oxygen species and cellular death. The IBD-associated E. coli LF82 induced the same dose-dependent inflammatory cytokine profile as ECN and ten of the new E. coli isolates displayed as high level IL-12p70, IL-1β, IL-23 and TNF-α from moDCs irrespective of their site of isolation (ileum/colon/faeces), disease origin (diseased/non-diseased) or known virulence factors. Contrarily, 691-04A and one new IBD E. coli isolate induced a different cellular phenotype with enhanced killing of moDCs and IECs, coupled to elevated IL-18. The cytopathic nature of 691-04A and one other IBD E. coli isolate suggests that colonization with specific non-diarrheagenic E. coli could promote intestinal barrier leakage and profound intestinal inflammation, while LF82, ECN and the remaining non-diarrheagenic E. coli isolates hold notorious pro-inflammatory characteristics that can progress inflammation in case of intestinal barrier leakage. Copyright © 2015 Elsevier GmbH. All rights reserved.

Whole genome sequencing of ESBL-producing Escherichia coli isolated from patients, farm waste and canals in Thailand.

PubMed

Runcharoen, Chakkaphan; Raven, Kathy E; Reuter, Sandra; Kallonen, Teemu; Paksanont, Suporn; Thammachote, Jeeranan; Anun, Suthatip; Blane, Beth; Parkhill, Julian; Peacock, Sharon J; Chantratita, Narisara

2017-09-06

Tackling multidrug-resistant Escherichia coli requires evidence from One Health studies that capture numerous potential reservoirs in circumscribed geographic areas. We conducted a survey of extended β-lactamase (ESBL)-producing E. coli isolated from patients, canals and livestock wastewater in eastern Thailand between 2014 and 2015, and analyzed isolates using whole genome sequencing. The bacterial collection of 149 isolates consisted of 84 isolates from a single hospital and 65 from the hospital sewer, canals and farm wastewater within a 20 km radius. E. coli ST131 predominated the clinical collection (28.6%), but was uncommon in the environment. Genome-based comparison of E. coli from infected patients and their immediate environment indicated low genetic similarity overall between the two, although three clinical-environmental isolate pairs differed by ≤ 5 single nucleotide polymorphisms. Thai E. coli isolates were dispersed throughout a phylogenetic tree containing a global E. coli collection. All Thai ESBL-positive E. coli isolates were multidrug resistant, including high rates of resistance to tobramycin (77.2%), gentamicin (77.2%), ciprofloxacin (67.8%) and trimethoprim (68.5%). ESBL was encoded by six different CTX-M elements and SHV-12. Three isolates from clinical samples (n = 2) or a hospital sewer (n = 1) were resistant to the carbapenem drugs (encoded by NDM-1, NDM-5 or GES-5), and three isolates (clinical (n = 1) and canal water (n = 2)) were resistant to colistin (encoded by mcr-1); no isolates were resistant to both carbapenems and colistin. Tackling ESBL-producing E. coli in this setting will be challenging based on widespread distribution, but the low prevalence of resistance to carbapenems and colistin suggests that efforts are now required to prevent these from becoming ubiquitous.

PREVALENCE OF SULFONAMIDE AND FLORFENICOL RESISTANCE GENES IN ESCHERICHIA COLI ISOLATED FROM YAKS (BOS GRUNNIENS) AND HERDSMEN IN THE TIBETAN PASTURE.

PubMed

Zhang, Anyun; Yang, Yunfei; Wang, Hongning; Lei, Changwei; Xu, Changwen; Guan, Zhongbin; Liu, Bihui; Huang, Xi; Peng, Linyao

2015-07-01

To determine the antimicrobial susceptibility profiles and prevalence of resistance genes in Escherichia coli isolated from yaks (Bos grunniens) and herdsmen in nine plateau pastures in Tibet, we isolated 184 nonidentical strains of E. coli from yaks and herdsmen. Antimicrobial susceptibility testing of 15 antimicrobials was conducted and the prevalence of sulfonamide resistance genes (sul1, sul2, and sul3) and florfenicol resistance genes (floR, cfr, cmlA, fexA, pexA, and estDL136) was determined. Escherichia coli isolated from yaks had a high resistance rate to sulfamethoxazole (44%), sulphafurazole (40.4%), and florfenicol (11.4%). Escherichia coli isolated from herdsmen had a high resistance rate to sulfamethoxazole (57%) and sulphafurazole (51%). In addition, sul genes were present in 93% of sulfonamide-resistant isolates (84/90), and 17 floR genes and four cmlA genes were found in 19 florfenicol-resistant isolates. Even though florfenicol is prohibited from use in humans, three floR genes were detected in strains isolated from herdsmen. The three floR-positive isolates from herdsmen had pulsed-field gel electrophoresis patterns similar to isolates from yaks. In addition to documenting the sul and floR genes in E. coli isolated from yaks and herdsmen in the Tibetan pasture, we demonstrated the potential risk that antimicrobial-resistant E. coli could spread among herdsmen and yaks.

Genotypic characterization of quinolone resistant-Escherichia coli isolates from retail food in Morocco.

PubMed

Nayme, Kaotar; Barguigua, Abouddihaj; Bouchrif, Brahim; Karraouan, Bouchra; El Otmani, Fatima; Elmdaghri, Naima; Zerouali, Khalid; Timinouni, Mohammed

2017-02-01

This study was conducted to assess the retail food as a possible vehicle for antimicrobial resistant, particularly quinolones resistant and pathogenic Escherichia coli. We determined the prevalence and characteristics of nalidixic acid (Nal) resistant E. coli isolates from diverse retail food samples. In all, 70 (28%) of 250 E. coli isolates studied were Nal-resistant E. coli and 91% of these were multi-drug resistant. Plasmid mediated quinolone resistance genes were identified in 32 isolates, including aac(6')-Ib-cr (n = 16), qnrS1 (n = 11) and qnrB19 (n = 7). Mutations in gyr A and par C genes were detected among 80% of the isolates, and the isolates showed substitution Ser83-Leu and Asp87-Asn in gyrA and Ser80-Ile in parC. In addition, three different gene cassettes were identified (aadA1, aadA7, aac(3)-Id) in 18%. Virulence-associated genes stx1, eae, sfa, hlyA and stx2 were found in six (8%), three (4%), two (3%), three (4%) and three (4%) isolates, respectively. E. coli isolates of phylogenetic group A were dominant (64%, 45/70). Pulsed field gel electrophoresis revealed none epidemiological relationship between these isolates. The results of this work report the higher frequency of Nal-resistant E. coli isolates from Moroccan retail food samples including MDR and pathogenic isolates.

Shiga toxin-converting phages and the emergence of new pathogenic Escherichia coli: a world in motion

PubMed Central

Tozzoli, Rosangela; Grande, Laura; Michelacci, Valeria; Ranieri, Paola; Maugliani, Antonella; Caprioli, Alfredo; Morabito, Stefano

2014-01-01

Shiga toxin (Stx)-producing Escherichia coli (STEC) are pathogenic E. coli causing diarrhea, hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS). STEC are characterized by a constellation of virulence factors additional to Stx and have long been regarded as capable to cause HC and HUS when possessing the ability of inducing the attaching and effacing (A/E) lesion to the enterocyte, although strains isolated from such severe infections sometimes lack this virulence feature. Interestingly, the capability to cause the A/E lesion is shared with another E. coli pathogroup, the Enteropathogenic E. coli (EPEC). In the very recent times, a different type of STEC broke the scene causing a shift in the paradigm for HUS-associated STEC. In 2011, a STEC O104:H4 caused a large outbreak with more than 800 HUS and 50 deaths. Such a strain presented the adhesion determinants of Enteroaggregative E. coli (EAggEC). We investigated the possibility that, besides STEC and EAggEC, other pathogenic E. coli could be susceptible to infection with stx-phages. A panel of stx2-phages obtained from STEC isolated from human disease was used to infect experimentally E. coli strains representing all the known pathogenic types, including both diarrheagenic E. coli (DEC) and extra-intestinal pathogenic E. coli (ExPEC). We observed that all the E. coli pathogroups used in the infection experiments were susceptible to the infection. Our results suggest that the stx2-phages used may not have specificity for E. coli adapted to the intestinal environment, at least in the conditions used. Additionally, we could only observe transient lysogens suggesting that the event of stable stx2-phage acquisition occurs rarely. PMID:24999453

Characterization of Escherichia coli O157:H7 from Downer and Healthy Dairy Cattle in the Upper Midwest Region of the United States

PubMed Central

Byrne, C. M.; Erol, I.; Call, J. E.; Kaspar, C. W.; Buege, D. R.; Hiemke, C. J.; Fedorka-Cray, P. J.; Benson, A. K.; Wallace, F. M.; Luchansky, J. B.

2003-01-01

While cattle in general have been identified as a reservoir of Escherichia coli O157:H7, there are limited data regarding the prevalence and clonality of this pathogen in downer dairy cattle and the potential impact to human health that may occur following consumption of meat derived from downer dairy cattle. In the present study, conducted at two slaughter facilities in Wisconsin between May and October of 2001, we established a higher prevalence of E. coli O157:H7 in fecal and/or tissue samples obtained aseptically from intact colons of downer dairy cattle (10 of 203, 4.9%) than in those from healthy dairy cattle (3 of 201, 1.5%). Analyses of 57 isolates, representing these 13 positive samples (one to five isolates per sample), by pulsed-field gel electrophoresis, revealed 13 distinct XbaI restriction endonuclease digestion profiles (REDP). Typically, isolates from different animals displayed distinct REDP and isolates from the same fecal or colon sample displayed indistinguishable REDP. However, in one sample, two different, but highly related, REDP were displayed by the isolates recovered. Antimicrobial susceptibility testing indicated that 10 of the 57 isolates, recovered from 2 (1 downer and 1 healthy animal) of the 13 positive samples, were resistant to at least 1 of 18 antimicrobials tested. However, there was no appreciable difference in the frequency of resistance of isolates recovered from downer and healthy dairy cattle, and not all isolates with the same REDP displayed the same antimicrobial susceptibility profile. Lastly, it was not possible to distinguish between isolates recovered from downer and healthy cattle based on their XbaI REDP or antimicrobial susceptibility. These results indicate that downer cattle had a 3.3-fold-higher prevalence of E. coli O157:H7 than healthy cattle within the time frame and geographic scope of this study. PMID:12902258

Occurrence and characterization of mcr-1-harbouring Escherichia coli isolated from pigs in Great Britain from 2013 to 2015.

PubMed

Duggett, Nicholas A; Sayers, Ellie; AbuOun, Manal; Ellis, Richard J; Nunez-Garcia, Javier; Randall, Luke; Horton, Robert; Rogers, Jon; Martelli, Francesca; Smith, Richard P; Brena, Camilla; Williamson, Susanna; Kirchner, Miranda; Davies, Robert; Crook, Derrick; Evans, Sarah; Teale, Chris; Anjum, Muna F

2017-03-01

To determine the occurrence of mcr-1 -harbouring Escherichia coli in archived pig material originating in Great Britain (GB) from 2013 to 2015 and characterize mcr-1 plasmids. Enrichment and selective culture of 387 archived porcine caecal contents and recovery from archive of 1109 E. coli isolates to identify colistin-resistant bacteria by testing for the presence of mcr-1 by PCR and RT-PCR. mcr-1 -harbouring E. coli were characterized by WGS and compared with other available mcr-1 WGS. Using selective isolation following enrichment, the occurrence of mcr-1 E. coli in caeca from healthy pigs at slaughter from unique farms in GB was 0.6% (95% CI 0%-1.5%) in 2015. mcr-1 E. coli were also detected in isolates from two porcine veterinary diagnostic submissions in 2015. All isolates prior to 2015 were negative. WGS analysis of the four mcr-1 -positive E. coli indicated no other antimicrobial resistance (AMR) genes were linked to mcr-1 -plasmid-bearing contigs, despite all harbouring multiple AMR genes. The sequence similarity between mcr-1 -plasmid-bearing contigs identified and those found in GB, Chinese and South African human isolates and Danish, French and Estonian livestock-associated isolates was 90%-99%. mcr-1- harbouring plasmids were diverse, implying transposable elements are involved in mcr-1 transmission in GB. The low number of mcr-1 -positive E. coli isolates identified suggested mcr-1 is currently uncommon in E. coli from pigs within GB. The high sequence similarity between mcr-1 plasmid draft genomes identified in pig E. coli and plasmids found in human and livestock-associated isolates globally requires further investigation to understand the full implications. © Crown copyright 2016.

Houseflies (Musca domestica) as Vectors for Extended-Spectrum β-Lactamase-Producing Escherichia coli on Spanish Broiler Farms.

PubMed

Solà-Ginés, Marc; González-López, Juan José; Cameron-Veas, Karla; Piedra-Carrasco, Nuria; Cerdà-Cuéllar, Marta; Migura-Garcia, Lourdes

2015-06-01

Flies may act as potential vectors for the spread of resistant bacteria to different environments. This study was intended to evaluate the presence of Escherichia coli strains resistant to cephalosporins in flies captured in the areas surrounding five broiler farms. Phenotypic and molecular characterization of the resistant population was performed by different methods: MIC determination, pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and phylotyping. The presence of extended-spectrum beta-lactamase (ESBL) genes, their plasmid location, and the mobile genetic elements involved in their mobilization were studied. Additionally, the presence of 35 genes associated with virulence was evaluated. Out of 682 flies captured, 42 yielded ESBL-producing E. coli. Of these isolates, 23 contained bla(CTX-M-1), 18 contained bla(CTX-M-14), and 1 contained bla(CTX-M-9). ESBL genes were associated mainly with the presence of the IncI1 and IncFIB replicons. Additionally, all the strains were multiresistant, and five of them also harbored qnrS. Identical PFGE profiles were found for E. coli isolates obtained from flies at different sampling times, indicating a persistence of the same clones in the farm environment over months. According to their virulence genes, 81% of the isolates were considered avian-pathogenic E. coli (APEC) and 29% were considered extraintestinal pathogenic E. coli (ExPEC). The entrance of flies into broiler houses constitutes a considerable risk for colonization of broilers with multidrug-resistant E. coli. ESBLs in flies reflect the contamination status of the farm environment. Additionally, this study demonstrates the potential contribution of flies to the dissemination of virulence and resistance genes into different ecological niches. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Escherichia coli global gene expression in urine from women with urinary tract infection.

PubMed

Hagan, Erin C; Lloyd, Amanda L; Rasko, David A; Faerber, Gary J; Mobley, Harry L T

2010-11-11

Murine models of urinary tract infection (UTI) have provided substantial data identifying uropathogenic E. coli (UPEC) virulence factors and assessing their expression in vivo. However, it is unclear how gene expression in these animal models compares to UPEC gene expression during UTI in humans. To address this, we used a UPEC strain CFT073-specific microarray to measure global gene expression in eight E. coli isolates monitored directly from the urine of eight women presenting at a clinic with bacteriuria. The resulting gene expression profiles were compared to those of the same E. coli isolates cultured statically to exponential phase in pooled, sterilized human urine ex vivo. Known fitness factors, including iron acquisition and peptide transport systems, were highly expressed during human UTI and support a model in which UPEC replicates rapidly in vivo. While these findings were often consistent with previous data obtained from the murine UTI model, host-specific differences were observed. Most strikingly, expression of type 1 fimbrial genes, which are among the most highly expressed genes during murine experimental UTI and encode an essential virulence factor for this experimental model, was undetectable in six of the eight E. coli strains from women with UTI. Despite the lack of type 1 fimbrial expression in the urine samples, these E. coli isolates were generally capable of expressing type 1 fimbriae in vitro and highly upregulated fimA upon experimental murine infection. The findings presented here provide insight into the metabolic and pathogenic profile of UPEC in urine from women with UTI and represent the first transcriptome analysis for any pathogenic E. coli during a naturally occurring infection in humans.

Cadmium tolerance and antibiotic resistance in Escherichia coli isolated from waste stabilization ponds.

PubMed

Patra, Sova; Das, T K; Avila, C; Cabello, V; Castillo, F; Sarkar, D; Lahiri, Susmita; Jana, B B

2012-04-01

The incidence pattern of cadmium tolerance and antibiotics resistance by Escherichia coli was examined periodically from the samples of water, sludge and intestine of fish raised in waste stabilization ponds in a sewage treatment plant. Samples of water and sludge were collected from all the selected ponds and were monitored for total counts of fecal coliform (FC), total coliform (TC) and the population of Escherichia coli, which was also obtained from the intestine of fishes. Total counts of both FC and TC as well as counts of E. coli were markedly reduced from the facultative pond to the last maturation pond. Tolerance limit to cadmium by E. coli tended to decline as the distance of the sewage effluent from the source increased; the effective lethal concentration of cadmium ranged from 0.1 mM in split chamber to 0.05 mM in first maturation pond. E. coli isolated from water, sludge and fish gut were sensitive to seven out of ten antibiotics tested. It appears that holistic functions mediated through the mutualistic growth of micro algae and heterotrophic bacteria in the waste stabilization ponds were responsible for the promotion of water quality and significant reduction of coliform along the sewage effluent gradient.

Presence and Antimicrobial Resistance of Escherichia coli in Ready-to-Eat Foods in Shaanxi, China.

PubMed

Baloch, Allah Bux; Yang, Hua; Feng, Yuqing; Xi, Meili; Wu, Qian; Yang, Qinhao; Tang, Jingsi; He, Xiangxiang; Xiao, Yingping; Xia, Xiaodong

2017-03-01

The aim of this study was to determine the presence and characteristics of Escherichia coli in ready-to-eat (RTE) foods. A total of 300 RTE foods samples were collected in Shaanxi Province, People's Republic of China: 50 samples of cooked meat, 165 samples of vegetable salad, 50 samples of cold noodles, and 35 samples of salted boiled peanuts. All samples were collected during summer (in July to October) 2011 and 2012 and surveyed for the presence of E. coli . E. coli isolates recovered were classified by phylogenetic typing using a PCR assay. The presence of Shiga toxin genes 1 (stx 1 ) and 2 (stx 2 ) was determined for these E. coli isolates by PCR, and all isolates were analyzed for antimicrobial susceptibility and the presence of class 1 integrons. Overall, 267 (89.0%) RTE food samples were positive for E. coli : 49 cold noodle, 46 cooked meat, 150 salad vegetable, and 22 salted boiled peanut samples. Of the 267 E. coli isolates, 73.0% belong to phylogenetic group A, 12.4% to group B1, 6.4% to group B2, and 8.2% to group D. All isolates were negative for both Shiga toxin genes. Among the isolates, 74.2% were resistant to at least one antimicrobial agent, and 17.6% were resistant to three or more antimicrobial agents. Resistance to ampicillin (75.6% of isolates) and tetracycline (73.1% of isolates) was most frequently detected; 26.2% of E. coli isolates and 68.8% of multidrug-resistant E. coli isolates were positive for class 1 integrons. All isolates were sensitive to amikacin. Our findings indicate that RTE foods in Shaanxi were commonly contaminated with antibiotic-resistant E. coli , which may pose a risk for consumer health and for transmission of antibiotic resistance. Future research is warranted to track the contamination sources and develop appropriate steps that should be taken by government, industry, and retailers to reduce microbial contamination in RTE foods.

Antimicrobial resistance and genetic profiling of Escherichia coli from a commercial beef packing plant.

PubMed

Aslam, Mueen; Service, Cara

2006-07-01

The objective of this study was to investigate the extent of antimicrobial resistance and to genetically characterize resistant Escherichia coli recovered from a commercial beef packing plant. E. coli isolates were recovered by a hydrophobic grid membrane filtration method by direct plating on SD-39 medium. A total of 284 isolates comprising 71, 36, 55, 52, and 70 isolates from animal hides, washed carcasses, conveyers, beef trimmings, and ground beef, respectively, were analyzed. The susceptibility of E. coli isolates to 15 antimicrobial agents was evaluated with an automated broth microdilution system, and the genetic characterization of these isolates was performed by the random amplified polymorphic DNA (RAPD) method. Of the 284 E. coli isolates, 56% were sensitive to all 15 antimicrobial agents. Resistance to tetracycline, ampicillin, and streptomycin was observed in 38, 9, and 6% of the isolates, respectively. Resistance to one or more antimicrobial agents was observed in 51% of the E. coli isolates recovered from the hides but in only 25% of the E. coli from the washed carcasses. Resistance to one or more antimicrobial agents was observed in 49, 50, and 37% of the isolates recovered from conveyers, beef trimmings, and ground beef, respectively. The RAPD pattern data showed that the majority of resistant E. coli isolates were genetically diverse. Only a few RAPD types of resistant strains were shared among various sample sources. The results of this study suggest that antimicrobial-resistant E. coli isolates were prevalent during all stages of commercial beef processing and that considerably higher numbers of resistant E. coli were present on conveyers, beef trimmings, and ground beef than on dressed carcasses. This stresses the need for improving hygienic conditions during all stages of commercial beef processing and meatpacking to avoid the risks of transfer of antimicrobial-resistant bacteria to humans.

[Pathogenic characteristics of Escherichia coli strains in cases of asymptomatic bacteriuria and symptomatic urinary tract infections].

PubMed

Misiewicz, I A; Galiński, J

1989-01-01

The aim of this study was to examine if E. coli isolated from asymptomatic bacteriuria differed in pathogenic features from strains isolated from symptomatic infections of urinary tract. In this study 130 strains of E. coli isolated from women having asymptomatic bacteriuria and 112 strains isolated from patients with symptoms of urinary tract infection were examined. It was shown that E. coli isolated from patients with symptomatic urinary tract infection showed the more frequently ability to cause mannose-resistant haemagglutination of human erythrocytes, resistance to bactericidal activity of serum and haemolytic properties than those isolated from asymptomatic bacteriuria. These strains showed also the higher ability to adhere to Vero cells in tissue culture. Among E. coli strains isolated from persons with asymptomatic bacteriuria the pathogenic features were most frequently found in strains from healthy women and the most rarely in isolated from diabetic women.

Genetic characteristics and antimicrobial resistance of Escherichia coli from Japanese macaques (Macaca fuscata) in rural Japan.

PubMed

Ogawa, Keiko; Yamaguchi, Keiji; Suzuki, Masatsugu; Tsubota, Toshio; Ohya, Kenji; Fukushi, Hideto

2011-04-01

Escherichia coli was isolated from wild and captive Japanese macaques (Macaca fuscata) to investigate the risk of zoonotic infections and the prevalence of antimicrobial-resistant Escherichia coli in the wild macaque population in Shimokita Peninsula, a rural area of Japan. We collected 265 fresh fecal samples from wild macaques and 20 samples from captive macaques in 2005 and 2006 for E. coli isolation. The predominant isolates were characterized by serotyping, virulence gene profiling, plasmid profiling, pulsed-field gel electrophoresis (PFGE), and microbial sensitivity tests. In total, 248 E. coli strains were isolated from 159 fecal samples from wild macaques, and 42 E. coli were isolated from 17 samples from captive macaques. None of the virulence genes eae, stx, elt, and est were detected in any of the isolates. The relatedness between wild- and captive-derived isolates was low by serotyping, PFGE, and plasmid profiling. Serotypes O8:H6, O8:H34, O8:H42, O8:HUT, O103:H27, O103:HNM, and OUT:H27 were found in wild macaque feces; serotypes O157:H42 and O119:H21 were recovered from captive macaques. O-and H-serotypes of the 26 isolates were not typed by commercial typing antisera and were named OUT and HUT, respectively. Twenty-eight isolates had no flagellar antigen, and their H-serotypes were named HNM. Similarity of PFGE patterns between wild-derived isolates and captive-derived isolates was <70%. No plasmid profile was shared between wild-derived and captive-derived isolates. The prevalence of antimicrobial-resistant E. coli was 6.5% (n=62) in wild macaques, and these isolates were resistant to cephalothin. We conclude that wild Japanese macaques in Shimokita Peninsula were unlikely to act as a reservoir of pathogenic E. coli for humans and that antimicrobial-resistant E. coli in wild macaques may be derived from humans.

Presence and characterization of shiga toxin-producing Escherichia coli and other potentially diarrheagenic E. coli strains in retail meats.

PubMed

Xia, Xiaodong; Meng, Jianghong; McDermott, Patrick F; Ayers, Sherry; Blickenstaff, Karen; Tran, Thu-Thuy; Abbott, Jason; Zheng, Jie; Zhao, Shaohua

2010-03-01

To determine the presence of Shiga toxin-producing Escherichia coli (STEC) and other potentially diarrheagenic E. coli strains in retail meats, 7,258 E. coli isolates collected by the U.S. National Antimicrobial Resistance Monitoring System (NARMS) retail meat program from 2002 to 2007 were screened for Shiga toxin genes. In addition, 1,275 of the E. coli isolates recovered in 2006 were examined for virulence genes specific for other diarrheagenic E. coli strains. Seventeen isolates (16 from ground beef and 1 from a pork chop) were positive for stx genes, including 5 positive for both stx(1) and stx(2), 2 positive for stx(1), and 10 positive for stx(2). The 17 STEC strains belonged to 10 serotypes: O83:H8, O8:H16, O15:H16, O15:H17, O88:H38, ONT:H51, ONT:H2, ONT:H10, ONT:H7, and ONT:H46. None of the STEC isolates contained eae, whereas seven carried enterohemorrhagic E. coli (EHEC) hlyA. All except one STEC isolate exhibited toxic effects on Vero cells. DNA sequence analysis showed that the stx(2) genes from five STEC isolates encoded mucus-activatable Stx2d. Subtyping of the 17 STEC isolates by pulsed-field gel electrophoresis (PFGE) yielded 14 distinct restriction patterns. Among the 1,275 isolates from 2006, 11 atypical enteropathogenic E. coli (EPEC) isolates were identified in addition to 3 STEC isolates. This study demonstrated that retail meats, mainly ground beef, were contaminated with diverse STEC strains. The presence of atypical EPEC strains in retail meat is also of concern due to their potential to cause human infections.

Antibiotic resistance and virulence genes in coliform water isolates.

PubMed

Stange, C; Sidhu, J P S; Tiehm, A; Toze, S

2016-11-01

Widespread fecal pollution of surface water may present a major health risk and a significant pathway for dissemination of antibiotic resistance bacteria. The River Rhine is one of the longest and most important rivers in Europe and an important raw water source for drinking water production. A total of 100 coliform isolates obtained from River Rhine (Germany) were examined for their susceptibility to seven antimicrobial agents. Resistances against amoxicillin, trimethoprim/sulfamethoxazole and tetracycline were detected in 48%, 11% and 9% of isolates respectively. The antibiotic resistance could be traced back to the resistance genes bla TEM , bla SHV , ampC, sul1, sul2, dfrA1, tet(A) and tet(B). Whereby, the ampC gene represents a special case, because its presence is not inevitably linked to a phenotypic antibiotic resistance. Multiple antibiotics resistance was often accompanied by the occurrence of class 1 or 2 integrons. E. coli isolates belonging to phylogenetic groups A and B1 (commensal) were more predominant (57%) compared to B2 and D groups (43%) which are known to carry virulent genes. Additionally, six E. coli virulence genes were also detected. However, the prevalence of virulence genes in the E. coli isolates was low (not exceeding 4.3% per gene) and no diarrheagenic E. coli pathotypes were detected. This study demonstrates that surface water is an important reservoir of ARGs for a number of antibiotic classes such as sulfonamide, trimethoprim, beta-lactam-antibiotics and tetracycline. The occurrence of antibiotic resistance in coliform bacteria isolated from River Rhine provides evidence for the need to develop management strategies to limit the spread of antibiotic resistant bacteria in aquatic environment. Copyright © 2016 Elsevier GmbH. All rights reserved.

Two outbreaks of diarrhoea in nurseries in Norway after farm visits, April to May 2009.

PubMed

Møller-Stray, J; Eriksen, H M; Bruheim, T; Kapperud, G; Lindstedt, B A; Skeie, Å; Sunde, M; Urdahl, A M; Øygard, B; Vold, L

2012-11-22

During a 2009 nationwide outbreak of sorbitolfermenting Escherichia coli O157 in Norway, the Norwegian Institute of Public Health was notified of diarrhoea outbreaks in two nurseries. A link to the nationwide outbreak was suspected and investigated, including retrospective cohort studies. Both nurseries had recently visited farms. Faecal specimens were obtained from symptomatic children as well as from the farm animals and tested for Campylobacter, Salmonella, Yersinia, Shigella and pathogenic E. coli, and isolates were further characterised. Nursery A had 12 symptomatic children, and we found the same strain of C. jejuni in faeces from children and lambs. Nursery B had nine symptomatic children, including one child with bloody diarrhoea carrying enterohaemorrhagic E. coli (EHEC) O26. EHEC O26 with a similar multiple-locus variable number tandem repeat analysis (MLVA)-profile was found in sheep. Five children had enteropathogenic E. coli (EPEC) O76. Animals were not tested for EPEC O76. We found no significant association between illness and risk factors for either nursery. The isolated pathogens differed from the one involved in the nationwide outbreak. In each nursery outbreak, the pathogens isolated from children matched those found in farm animals, implicating animal faeces as the source. Hygiene messages are important to prevent similar outbreaks.

Occurrence of mannose resistant hemagglutinins in Escherichia coli strains isolated from porcine colibacillosis.

PubMed

Truszczyński, M; Osek, J

1987-01-01

Three-hundred and fifty-eight E. coli strains isolated from piglets were tested for the presence of hemagglutinins by the use of the active hemagglutination test with or without mannose. Additionally 86 strains from the mentioned number of strains were investigated for the presence of common fimbriae using the same method but growing the strains in media especially suited for the development of this kind of fimbriae. These 358 strains and additionally 202 E. coli strains were tested using antisera for 987P and K88 antigens. It was found, using the active hemagglutination test, that 51.4% of the strains were hemagglutinating. The hemagglutinating strains carried the K88 antigen. All these strains were isolated from new-born and weaned piglets with enterotoxic form of colibacillosis, called also E. coli diarrhea. From cases of this form of colibacillosis originated also 26.7% of the strains in which common fimbriae (type 1) were detected. This result was obtained when the BHI medium was used for cultivation. In case of TSA medium only 2.3% of strains were positive. No specific or common fimbriae were found in strains recovered from septic form of colibacillosis and oedema disease (called also enterotoxaemic form of colibacillosis). No strain of 560 examined showed the presence of fimbrial 987P antigen.

Are super-shedder feedlot cattle really super?

PubMed

Munns, Krysty D; Selinger, Lorna; Stanford, Kim; Selinger, L Brent; McAllister, Tim A

2014-04-01

The objective of this study was to determine the frequency and duration of super-shedding in cattle by enumerating Escherichia coli O157:H7 in feces and to compare lineage and pulsed-field gel electrophoresis (PFGE) subtypes from super- and low-shedders. E. coli O157:H7 was enumerated from fecal samples obtained from the rectums of 400 feedlot cattle. Super-shedding steers (N=11) were identified, transported, and penned individually. Freshly voided fecal pats were sampled 2 h before and 6 h after feeding for 7 d, then once daily for an additional 19 d. Isolates (N=126) were subtyped using PFGE, and lineage was typed using a lineage-specific polymorphism assay. Of the 11 super-shedders identified at the commercial feedlot, only five were confirmed as super-shedders at the research feedlot, with no super-shedders identified 6 d after sampling at the commercial feedlot. Super-shedding was not consistent in fecal pats collected from the same individual at different times of the day. Isolates exhibited three distinct PFGE subtypes, with most isolates (97.6%) displaying the same subtype, including those obtained from steers that transitioned from super- to low-shedding. The short duration of super-shedding and its lack of continuance suggest that these individuals may not play as great a role in the dissemination of E. coli O157:H7 within the feedlot as previously proposed.

Antimicrobial resistant coliform bacteria in the Gomti river water and determination of their tolerance level.

PubMed

Akhter, Asma; Imran, Mohd; Akhter, Firoz

2014-01-01

The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among coliform in the Gomti river water samples was investigated. The coliform populations were isolated on Mac Conky and eosin methylene blue (EMB) agar plates supplemented with antibiotics. The incidence of resistance among the coliform population varied considerably in different drug and water sampling sites. Coliform bacteria showed lower drug resistant viable count in sampling site-III (receiving treated wastewater) as compared to more polluted site-I and site-II. Viable count of coliform population obtained on both medium was recorded higher against erythromycin from sampling site-III. Lower viable count of coliforms was recorded against tetracycline in site-II and III. Similar resistance pattern was obtained in the frequency of E. coli and Enterobacter species from all the three sampling sites. Percentage of antibiotic resistant E. coli was observed higher than Enterobacter spp among the total coliforms against all antibiotics tested without Erythromycin and penicillin in site-I and II respectively. Isolates of E. coli and Enterobacter spp. showed their tolerance level (MIC) in the range of 2-100 against the antibiotics tested. Maximum number of isolates of both genus exhibited their MICs at lower concentration range 2-5µg/ml against ciprofloxacin, tetracyclin and amoxycillin. EMB - Eosin methylene blue, IMViC tests - Indole, Methyl Red, Voges Proskauer and Citrate Utilization Tests, MIC - Minimum inhibitory concentration.

Antimicrobial resistant coliform bacteria in the Gomti river water and determination of their tolerance level

PubMed Central

Akhter, Asma; Imran, Mohd; Akhter, Firoz

2014-01-01

The distribution of resistance to ampicillin, chloramphenicol, sulfonamides, tetracycline, and streptomycin among coliform in the Gomti river water samples was investigated. The coliform populations were isolated on Mac Conky and eosin methylene blue (EMB) agar plates supplemented with antibiotics. The incidence of resistance among the coliform population varied considerably in different drug and water sampling sites. Coliform bacteria showed lower drug resistant viable count in sampling site-III (receiving treated wastewater) as compared to more polluted site-I and site-II. Viable count of coliform population obtained on both medium was recorded higher against erythromycin from sampling site-III. Lower viable count of coliforms was recorded against tetracycline in site-II and III. Similar resistance pattern was obtained in the frequency of E. coli and Enterobacter species from all the three sampling sites. Percentage of antibiotic resistant E. coli was observed higher than Enterobacter spp among the total coliforms against all antibiotics tested without Erythromycin and penicillin in site-I and II respectively. Isolates of E. coli and Enterobacter spp. showed their tolerance level (MIC) in the range of 2-100 against the antibiotics tested. Maximum number of isolates of both genus exhibited their MICs at lower concentration range 2-5µg/ml against ciprofloxacin, tetracyclin and amoxycillin. Abbreviations EMB - Eosin methylene blue, IMViC tests - Indole, Methyl Red, Voges Proskauer and Citrate Utilization Tests, MIC - Minimum inhibitory concentration. PMID:24966515

Genetic Diversity and Antibiotic Resistance of Escherichia coli Isolates from Different Leafy Green Production Systems.

PubMed

Jongman, Mosimanegape; Korsten, Lise

2016-11-01

Foodborne disease outbreaks linked to contaminated irrigation water and fresh produce are a public health concern. The presence of Escherichia coli isolates from irrigation water and leafy green vegetables in different food production systems (large commercial farms, small-scale farms, and homestead gardens) was investigated. The prevalence of antibiotic resistance and virulence in these isolates was further assessed, and links between water source and irrigated crops were identified using antimicrobial and genotypic analyses. Presumptive E. coli isolates were identified by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, and identities were confirmed by PCR using the uidA gene. Antimicrobial susceptibility was evaluated with the Kirby Bauer disk diffusion test; the presence of virulence genes was determined with enterobacterial repetitive intergenic consensus PCR assays. Of the 130 E. coli isolates from water (n =60) and leafy green vegetables (n =70), 19 (14.6%) were resistant to one antibiotic (tetracycline) and 92 (70.7%) were resistant to various antibiotics (including ampicillin, cefoxitin, and nalidixic acid). All E. coli isolates were susceptible to ceftriaxone and gentamicin. The virulence gene stx 2 was detected in E. coli isolates from irrigation water (8 [13.3%] of 60 isolates) and cabbages (3 [7.5%] of 40), but the virulence genes eae and stx 1 were not detected in any tested isolates from irrigation water and fresh produce samples. The prevalence of multidrug-resistant E. coli was lower in isolates from GLOBALG.A.P.-certified farms than in isolates from noncertified commercial and small-scale farms and homestead gardens. A link between the E. coli isolates from irrigation water sources and leafy green vegetables was established with phenotypic (antimicrobial) and genotypic (DNA fingerprinting) analyses. However, a link between virulence genes and the prevalence of antimicrobial resistance could not be established.

Draft genomic sequencing of six potential extraintestinal pathogenic Escherichia coli isolates from retail chicken meat.

USDA-ARS?s Scientific Manuscript database

Potential Extraintestinal pathogenic Escherichia coli isolates DP254, WH333, WH398, F356, FEX675 and FEX725 were isolated from retail chicken meat products. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used in food safety research....

Distribution of sulfonamide resistance genes in Escherichia coli and Salmonella isolates from swine and chickens at abattoirs in Ontario and Québec, Canada.

PubMed

Kozak, Gosia K; Pearl, David L; Parkman, Julia; Reid-Smith, Richard J; Deckert, Anne; Boerlin, Patrick

2009-09-01

Sulfonamide-resistant Escherichia coli and Salmonella isolates from pigs and chickens in Ontario and Québec were screened for sul1, sul2, and sul3 by PCR. Each sul gene was distributed differently across populations, with a significant difference between distribution in commensal E. coli and Salmonella isolates and sul3 restricted mainly to porcine E. coli isolates.

Distribution of Sulfonamide Resistance Genes in Escherichia coli and Salmonella Isolates from Swine and Chickens at Abattoirs in Ontario and Québec, Canada ▿

PubMed Central

Kozak, Gosia K.; Pearl, David L.; Parkman, Julia; Reid-Smith, Richard J.; Deckert, Anne; Boerlin, Patrick

2009-01-01

Sulfonamide-resistant Escherichia coli and Salmonella isolates from pigs and chickens in Ontario and Québec were screened for sul1, sul2, and sul3 by PCR. Each sul gene was distributed differently across populations, with a significant difference between distribution in commensal E. coli and Salmonella isolates and sul3 restricted mainly to porcine E. coli isolates. PMID:19633109

Experimental mouse lethality of Escherichia coli strains isolated from free ranging Tibetan yaks.

PubMed

Rehman, Mujeeb Ur; Zhang, Hui; Wang, Yajing; Mehmood, Khalid; Huang, Shucheng; Iqbal, Muhammad Kashif; Li, Jiakui

2017-08-01

The present study has examined the virulence potential of Escherichia coli isolates harboring at least one virulence gene (associated with ExPEC or InPEC pathotype and belonging to different phylogenetic groups: A, B1, B2 or D), isolated from free ranging Tibetan yak feces. The E. coli isolates (n = 87) were characterized for different serogroups and a mouse model of subcutaneous-infection was used to envisage the virulence within these E. coli strains. Of the 87 E. coli isolates examined, 23% of the E. coli isolates caused lethal infections in a mouse model of subcutaneous infection and were classified as killer. Moreover, the majority of the killer strains belonged to phylogroup A (65%) and serogroup O 60 or O 101 (35%). Phylogroup B1, serogroups O 60 and O 101 were statistically associated with the killer status (P < 0.05). However, positive associations (OR >1) were observed between the killer status isolates and all other bacterial virulence traits. This study comprises the first report on the virulence potential of E. coli strains isolated from free-ranging Tibetan yaks feces. Our findings suggest that pathogenic E. coli of free ranging yaks is highly worrisome, as these feces are used as manures by farmers and therewith pose a health risk to humans upon exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Zoonotic potential of Escherichia coli isolates from retail chicken meat products and eggs.

PubMed

Mitchell, Natalie M; Johnson, James R; Johnston, Brian; Curtiss, Roy; Mellata, Melha

2015-02-01

Chicken products are suspected as a source of extraintestinal pathogenic Escherichia coli (ExPEC), which causes diseases in humans. The zoonotic risk to humans from chicken-source E. coli is not fully elucidated. To clarify the zoonotic risk posed by ExPEC in chicken products and to fill existing knowledge gaps regarding ExPEC zoonosis, we evaluated the prevalence of ExPEC on shell eggs and compared virulence-associated phenotypes between ExPEC and non-ExPEC isolates from both chicken meat and eggs. The prevalence of ExPEC among egg-source isolates was low, i.e., 5/108 (4.7%). Based on combined genotypic and phenotypic screening results, multiple human and avian pathotypes were represented among the chicken-source ExPEC isolates, including avian-pathogenic E. coli (APEC), uropathogenic E. coli (UPEC), neonatal meningitis E. coli (NMEC), and sepsis-associated E. coli (SEPEC), as well as an undefined ExPEC group, which included isolates with fewer virulence factors than the APEC, UPEC, and NMEC isolates. These findings document a substantial prevalence of human-pathogenic ExPEC-associated genes and phenotypes among E. coli isolates from retail chicken products and identify key virulence traits that could be used for screening. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Characterization of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli obtained from Danish pigs, pig farmers and their families from farms with high or no consumption of third- or fourth-generation cephalosporins.

PubMed

Hammerum, Anette M; Larsen, Jesper; Andersen, Vibe D; Lester, Camilla H; Skovgaard Skytte, Timmy S; Hansen, Frank; Olsen, Stefan S; Mordhorst, Hanne; Skov, Robert L; Aarestrup, Frank M; Agersø, Yvonne

2014-10-01

To compare and characterize extended-spectrum β-lactamase (ESBL)-producing Escherichia coli from pigsties, pig farmers and their families on farms with previous high or no use of third- or fourth-generation cephalosporins. Twenty farms with no third- or fourth-generation cephalosporin use and 19 herds with previous frequent use were included. The ESBL-producing isolates detected in humans and pigs were characterized by ESBL genotype, PFGE, susceptibility to non-β-lactam antibiotics and phylotype, and selected isolates were characterized by multilocus sequence typing (MLST). Furthermore, transferability of bla(CTX-M-)1 from both human and pig isolates was studied and plasmid incompatibility groups were defined. The volunteers answered a questionnaire including epidemiological risk factors for carriage of ESBL-producing E. coli. ESBL-producing E. coli was detected in pigs on 79% of the farms with high consumption of cephalosporins compared with 20% of the pigs on farms with no consumption. ESBL-producing E. coli was detected in 19 of the 195 human participants and all but one had contact with pigs. The genes found in both humans and pigs at the same farms were blaCTX-M-1 (eight farms), bla(CTX-M-14) (one farm) and bla(SHV-12) (one farm). At four farms ESBL-producing E. coli isolates with the same CTX-M enzyme, phylotype, PFGE type and MLST type were detected in both pigs and farmers. The majority of the plasmids with bla(CTX-M-1) were transferable by conjugation and belonged to incompatibility group IncI1, IncF, or IncN. The present study shows an increased frequency of ESBL-producing E. coli on farms with high consumption of third- or fourth-generation cephalosporins and indicates transfer of either ESBL-producing E. coli or plasmids between pigs and farmers. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Vaginal versus Obstetric Infection Escherichia coli Isolates among Pregnant Women: Antimicrobial Resistance and Genetic Virulence Profile.

PubMed

Sáez-López, Emma; Guiral, Elisabet; Fernández-Orth, Dietmar; Villanueva, Sonia; Goncé, Anna; López, Marta; Teixidó, Irene; Pericot, Anna; Figueras, Francesc; Palacio, Montse; Cobo, Teresa; Bosch, Jordi; Soto, Sara M

2016-01-01

Vaginal Escherichia coli colonization is related to obstetric infections and the consequent development of infections in newborns. Ampicillin resistance among E. coli strains is increasing, which is the main choice for treating empirically many obstetric and neonatal infections. Vaginal E. coli strains are very similar to extraintestinal pathogenic E. coli with regards to the virulence factors and the belonging to phylogroup B2. We studied the antimicrobial resistance and the genetic virulence profile of 82 E. coli isolates from 638 vaginal samples and 63 isolated from endometrial aspirate, placental and amniotic fluid samples from pregnant women with obstetric infections. The prevalence of E. coli in the vaginal samples was 13%, which was significant among women with associated risk factors during pregnancy, especially premature preterm rupture of membranes (p<0.0001). Sixty-five percent of the strains were ampicillin-resistant. The E. coli isolates causing obstetric infections showed higher resistance levels than vaginal isolates, particularly for gentamicin (p = 0.001). The most prevalent virulence factor genes were those related to the iron uptake systems revealing clear targets for interventions. More than 50% of the isolates belonged to the virulent B2 group possessing the highest number of virulence factor genes. The ampicillin-resistant isolates had high number of virulence factors primarily related to pathogenicity islands, and the remarkable gentamicin resistance in E. coli isolates from women presenting obstetric infections, the choice of the most appropriate empiric treatment and clinical management of pregnant women and neonates should be carefully made. Taking into account host-susceptibility, the heterogeneity of E. coli due to evolution over time and the geographical area, characterization of E. coli isolates colonizing the vagina and causing obstetric infections in different regions may help to develop interventions and avoid the aetiological link between maternal carriage and obstetric and subsequent puerperal infections.

Isolation of Escherichia coli 0157:H7 Strain from Fecal Samples of Zoo Animal

PubMed Central

Mohammed Hamzah, Aseel; Mohammed Hussein, Aseel; Mahmoud Khalef, Jenan

2013-01-01

The isolation and characterization of Escherichia coli O157:H7 strains from 22 out of 174 fecal samples from petting zoo animals representing twenty-two different species (camel, lion, goats, zebra, bear, baboon monkey, Siberian monkey, deer, elk, llama, pony, horses, fox, kangaroo, wolf, porcupine, chickens, tiger, ostrich, hyena, dogs, and wildcats) were investigated. One petting Al-Zawraa zoological society of Baghdad was investigated for E. coli O157:H7 over a 16-month period that spanned two summer and two autumn seasons. Variation in the occurrence of E. coli O157:H7-positive petting zoo animals was observed, with animals being culture positive only in the summer months but not in the spring, autumn, or winter. E. coli O157:H7 isolates were distinguished by agglutination with E. coli O157:H7 latex reagent (Oxoid), identified among the isolates, which showed that multiple E. coli strains were isolated from one petting zoo animal, in which a single animal simultaneously shed multiple E. coli strains; E. coli O157:H7 was isolated only by selective enrichment culture of 2 g of petting zoo animal feces. In contrast, strains other than O157:H7 were cultured from feces of petting zoo animals without enrichment. PMID:24489514

Isolation of Escherichia coli 0157:H7 strain from fecal samples of zoo animal.

PubMed

Mohammed Hamzah, Aseel; Mohammed Hussein, Aseel; Mahmoud Khalef, Jenan

2013-01-01

The isolation and characterization of Escherichia coli O157:H7 strains from 22 out of 174 fecal samples from petting zoo animals representing twenty-two different species (camel, lion, goats, zebra, bear, baboon monkey, Siberian monkey, deer, elk, llama, pony, horses, fox, kangaroo, wolf, porcupine, chickens, tiger, ostrich, hyena, dogs, and wildcats) were investigated. One petting Al-Zawraa zoological society of Baghdad was investigated for E. coli O157:H7 over a 16-month period that spanned two summer and two autumn seasons. Variation in the occurrence of E. coli O157:H7-positive petting zoo animals was observed, with animals being culture positive only in the summer months but not in the spring, autumn, or winter. E. coli O157:H7 isolates were distinguished by agglutination with E. coli O157:H7 latex reagent (Oxoid), identified among the isolates, which showed that multiple E. coli strains were isolated from one petting zoo animal, in which a single animal simultaneously shed multiple E. coli strains; E. coli O157:H7 was isolated only by selective enrichment culture of 2 g of petting zoo animal feces. In contrast, strains other than O157:H7 were cultured from feces of petting zoo animals without enrichment.

Phylogenetic Group Determination of Escherichia coli Isolated from Animals Samples

PubMed Central

Morcatti Coura, Fernanda; Diniz, Soraia de Araújo; Silva, Marcos Xavier; Mussi, Jamili Maria Suhet; Barbosa, Silvia Minharro; Lage, Andrey Pereira; Heinemann, Marcos Bryan

2015-01-01

This study analyzes the occurrence and distribution of phylogenetic groups of 391 strains of Escherichia coli isolated from poultry, cattle, and water buffalo. The frequency of the phylogroups was A = 19%, B1 = 57%, B2 = 2.3%, C = 4.6%, D = 2.8%, E = 11%, and F = 3.3%. Phylogroups A (P < 0.001) and F (P = 0.018) were associated with E. coli strains isolated from poultry, phylogroups B1 (P < 0.001) and E (P = 0.002) were associated with E. coli isolated from cattle, and phylogroups B2 (P = 0.003) and D (P = 0.017) were associated with E. coli isolated from water buffalo. This report demonstrated that some phylogroups are associated with the host analyzed and the results provide knowledge of the phylogenetic composition of E. coli from domestic animals. PMID:26421310

Norwegian Sheep Are an Important Reservoir for Human-Pathogenic Escherichia coli O26:H11

PubMed Central

Sekse, Camilla; Lindstedt, Bjørn-Arne; Sunde, Marianne; Løbersli, Inger; Urdahl, Anne Margrete; Kapperud, Georg

2012-01-01

A previous national survey of Escherichia coli in Norwegian sheep detected eae-positive (eae+) E. coli O26:H11 isolates in 16.3% (80/491) of the flocks. The purpose of the present study was to evaluate the human-pathogenic potential of these ovine isolates by comparing them with E. coli O26 isolates from humans infected in Norway. All human E. coli O26 isolates studied carried the eae gene and shared flagellar type H11. Two-thirds of the sheep flocks and 95.1% of the patients harbored isolates containing arcA allele type 2 and espK and were classified as enterohemorrhagic E. coli (EHEC) (stx positive) or EHEC-like (stx negative). These isolates were further divided into group A (EspK2 positive), associated with stx2-EDL933 and stcEO103, and group B (EspK1 positive), associated with stx1a. Although the stx genes were more frequently present in isolates from patients (46.3%) than in those from sheep flocks (5%), more than half of the ovine isolates in the EHEC/EHEC-like group had multiple-locus variable number of tandem repeat analysis (MLVA) profiles that were identical to those seen in stx-positive human O26:H11 isolates. This indicates that EHEC-like ovine isolates may be able to acquire stx-carrying bacteriophages and thereby have the possibility to cause serious illness in humans. The remaining one-third of the sheep flocks and two of the patients had isolates fulfilling the criteria for atypical enteropathogenic E. coli (aEPEC): arcA allele type 1 and espK negative (group C). The majority of these ovine isolates showed MLVA profiles not previously seen in E. coli O26:H11 isolates from humans. However, according to their virulence gene profile, the aEPEC ovine isolates should be considered potentially pathogenic for humans. In conclusion, sheep are an important reservoir of human-pathogenic E. coli O26:H11 isolates in Norway. PMID:22492457

Isolation of non-sporing anaerobic rods from infections in children.

PubMed

Brook, I

1996-07-01

From 1974 to 1994, 2033 microbiological specimens from children were submitted for cultures for anaerobic bacteria. Fifty-seven isolates of Bifidobacterium spp. were obtained from 55 (3%) children, 67 isolates of Eubacterium spp. from 65 (3%) children and 41 isolates of Lactobacillus spp. from 40 (2%) children. Most Bifidobacterium isolates were from chronic otitis media, abscesses, peritonitis, aspiration pneumonia and paronychia. Most Eubacterium isolates were from abscesses, peritonitis, decubitus ulcers and bites. Lactobacillus spp. were mainly isolated from abscesses, aspiration pneumonia, bacteraemia and conjunctivitis. Most (> 90%) infections from which these species were isolated were polymicrobial and yielded a mixture of aerobic and anaerobic bacteria. The organisms most commonly isolated with the non-sporing anaerobic gram-positive rods were Peptostreptococcus spp., Bacteroides spp., pigmented Prevotella and Porphyromonas spp., Fusobacterium spp., Staphylococcus aureus and Escherichia coli. Most Bacteroides spp. and E. coli were isolated from intra-abdominal infection and skin and soft tissue infection around the rectal area, whereas most Prevotella, Porphyromonas and Fusobacterium isolates were from oropharyngeal, pulmonary and head and neck sites. The predisposing conditions associated with the isolation of non-sporing anaerobic gram-positive rods were previous surgery, malignancy, steroid therapy and immunodeficiency. Antimicrobial therapy was given to 149 (83%) of the 160 patients, in conjunction with surgical drainage or correction of pathology in 89 (56%).

Evaluation of the bacteriological quality of ice cream sold at San Jose, Costa Rica.

PubMed

Windrantz, P; Arias, M L

2000-09-01

The presence of total and fecal coliforms, E. coli, Listeria sp and Salmonella sp. was evaluated in 65 samples of both commercial and homemade ice cream. 37.1% of homemade ice cream and 20% of commercial ice cream did not fulfill the international standard for total coliforms. At the same time 82.9% of home made samples and 56.7% of commercial ones presented fecal coliforms. E. coli was found in 51.4% of home made samples and 26.7% of commercial ones. Sixteen Listeria sp. isolates were obtained, 50% corresponded to Listeria monocytogenes and 50% to L. innocua. The overall presence of L. monocytogenes in ice cream samples was of 12.3% and it was isolated in all cases, from homemade ice cream samples. Salmonella was not isolated from the samples analyzed. Although the results obtained show an important improvement in the quality of ice cream, compared with a previous work done also in Costa Rica, further efforts shall be done, in order to offer safe products to consumers.

Prevalence, Antibiotic Susceptibility, and Diversity of Escherichia coli O157:H7 Isolates from a Longitudinal Study of Beef Cattle Feedlots†

PubMed Central

Galland, John C.; Hyatt, Doreene R.; Crupper, Scott S.; Acheson, David W.

2001-01-01

Prevalence, antibiotic susceptibility, and genetic diversity were determined for Escherichia coli O157:H7 isolated over 11 months from four beef cattle feedlots in southwest Kansas. From the fecal pat (17,050) and environmental (7,134) samples collected, 57 isolates of E. coli O157:H7 were identified by use of bacterial culture and latex agglutination (C/LA). PCR showed that 26 isolates were eaeA gene positive. Escherichia coli O157:H7 was identified in at least one of the four feedlots in 14 of the 16 collections by C/LA and in 9 of 16 collections by PCR, but consecutive positive collections at a single feedlot were rare. Overall prevalence in fecal pat samples was low (0.26% by C/LA, and 0.08% by PCR). No detectable differences in prevalence or antibiotic resistance were found between isolates collected from home pens and those from hospital pens, where antibiotic use is high. Resistant isolates were found for six of the eight antibiotics that could be used to treat E. coli infections in food animals, but few isolates were multidrug resistant. The high diversity of isolates as measured by random amplification of polymorphic DNA and other characteristics indicates that the majority of isolates were unique and did not persist at a feedlot, but probably originated from incoming cattle. The most surprising finding was the low frequency of virulence markers among E. coli isolates identified initially by C/LA as E. coli O157:H7. These results demonstrate that better ways of screening and confirming E. coli O157:H7 isolates are required for accurate determination of prevalence. PMID:11282614

Evidence for Transfer of CMY-2 AmpC β-Lactamase Plasmids between Escherichia coli and Salmonella Isolates from Food Animals and Humans

PubMed Central

Winokur, P. L.; Vonstein, D. L.; Hoffman, L. J.; Uhlenhopp, E. K.; Doern, G. V.

2001-01-01

Escherichia coli is an important pathogen that shows increasing antimicrobial resistance in isolates from both animals and humans. Our laboratory recently described Salmonella isolates from food animals and humans that expressed an identical plasmid-mediated, AmpC-like β-lactamase, CMY-2. In the present study, 59 of 377 E. coli isolates from cattle and swine (15.6%) and 6 of 1,017 (0.6%) isolates of human E. coli from the same geographic region were resistant to both cephamycins and extended-spectrum cephalosporins. An ampC gene could be amplified with CMY-2 primers in 94.8% of animal and 33% of human isolates. Molecular epidemiological studies of chromosomal DNA revealed little clonal relatedness among the animal and human E. coli isolates harboring the CMY-2 gene. The ampC genes from 10 animal and human E. coli isolates were sequenced, and all carried an identical CMY-2 gene. Additionally, all were able to transfer a plasmid containing the CMY-2 gene to a laboratory strain of E. coli. CMY-2 plasmids demonstrated two different plasmid patterns that each showed strong similarities to previously described Salmonella CMY-2 plasmids. Additionally, Southern blot analyses using a CMY-2 probe demonstrated conserved fragments among many of the CMY-2 plasmids identified in Salmonella and E. coli isolates from food animals and humans. These data demonstrate that common plasmids have been transferred between animal-associated Salmonella and E. coli, and identical CMY-2 genes carried by similar plasmids have been identified in humans, suggesting that the CMY-2 plasmid has undergone transfer between different bacterial species and may have been transmitted between food animals and humans. PMID:11557460

Isolation and characterization of Shiga toxin-producing Escherichia coli O157:H7 and non-O157 from beef carcasses at a slaughter plant in Mexico.

PubMed

Varela-Hernández, J J; Cabrera-Diaz, E; Cardona-López, M A; Ibarra-Velázquez, L M; Rangel-Villalobos, H; Castillo, A; Torres-Vitela, M R; Ramírez-Alvarez, A

2007-01-25

The contamination of beef carcasses with Shiga toxin-producing O157:H7 and non-O157 Escherichia coli (STEC) obtained from a slaughter plant in Guadalajara, Mexico was investigated. A total of 258 beef carcasses were sampled during a 12-month period. All samples were assayed for STEC by selective enrichment in modified tryptone soy broth supplemented with cefixime, cefsulodin and vancomycin, followed by plating on Sorbitol MacConkey Agar supplemented with cefixime and tellurite (CT-SMAC). Simultaneously, all samples were assayed by immunomagnetic separation (IMS) and plated on CT-SMAC and CHROMagar. The presence of the stx1, stx2, eaeA and hly933 genes, recognized as major virulence factors of STEC, was tested for O157:H7 and non-O157 E. coli isolates by multiplex polymerase chain reaction (PCR). STEC was detected in two (0.8%) samples. One of these STEC isolates corresponded to the serotype O157:H7 showing stx2, eaeA and hyl933 genes. The other isolate corresponded to non-O157 STEC and only had the stx1 gene. Thirteen carcasses (5%) were positive for nonmotile E. coli O157 and 7 (2.7%) were positive for E. coli O157:H7. The presence of O157:H7 and non-O157 STEC on beef carcasses in this slaughter plant in Guadalajara, Mexico, emphasizes the importance of implementing the Hazard Analysis and Critical Control Point (HACCP) system, as well as the need for implementing, evaluating, and validating antimicrobial interventions to reduce the presence of potential pathogenic microorganisms.

Community-onset extended-spectrum-β-lactamase-producing Escherichia coli sequence type 131 at two Korean community hospitals: The spread of multidrug-resistant E. coli to the community via healthcare facilities.

PubMed

Kim, Young Ah; Kim, Jin Ju; Kim, Heejung; Lee, Kyungwon

2017-01-01

The recent molecular epidemiology of ESBL-producing Escherichia coli infection in two Korean community hospitals was evaluated in this prospective observational study. We collected non-duplicated E. coli isolates from consecutive, sequentially encountered patients with community-onset episodes between March and April 2016 in two community hospitals in Gyeonggi-do province, Korea. We studied the prevalence, clinical characteristics and molecular epidemiology of E. coli sequence type 131 (ST131) isolated from the community. From a total of 213 E. coli isolates collected from the community, 94 (44.1%) were community-onset healthcare-associated isolates and 119 (55.9%) were community-associated isolates, of which urinary tract infection was the majority. A total of 55 (25.8%) of the 213 E. coli isolates were confirmed to have ESBL genes, which were mainly CTX-M types such as CTX-M-14 and CTX-M-15. There was no difference in the proportion of globally epidemic ST131 clones or that of O25, O16, H30, or H30Rx subclones between community-associated and community-onset healthcare-associated isolates. In this study, considerable ST131 E. coli isolations in the community were observed and about half of them were related to the history of a visit to the healthcare facilities, indicating the spread of multidrug-resistant E. coli to the community via healthcare facilities. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Occurrence and antimicrobial resistance of pathogenic Escherichia coli and Salmonella spp. in retail raw table eggs sold for human consumption in Enugu state, Nigeria

PubMed Central

Okorie-Kanu, O. Josephine; Ezenduka, E. Vivienne; Okorie-Kanu, C. Onwuchokwe; Ugwu, L. Chinweokwu; Nnamani, U. John

2016-01-01

Aim: This study was conducted to investigate the occurrence of pathogenic Escherichia coli and Salmonella species in retail raw table eggs sold for human consumption in Enugu State and to determine the resistance of these pathogens to antimicrobials commonly used in human and veterinary practices in Nigeria. Materials and Methods: A total of 340 raw table eggs comprising 68 composite samples (5 eggs per composite sample) were collected from five selected farms (13 composite samples from the farms) and 10 retail outlets (55 composite samples from the retail outlets) in the study area over a period of 4-month (March-June, 2014). The eggs were screened for pathogenic E. coli and Salmonella species following standard procedures within 24 h of sample collection. Isolates obtained were subjected to in-vitro antimicrobial susceptibility test with 15 commonly used antimicrobials using the disk diffusion method. Results: About 37 (54.4%) and 7 (10.3%) of the 68 composite samples were positive for pathogenic E. coli and Salmonella species, respectively. The shells showed significantly higher (p<0.05) contaminations than the contents for both microorganisms. The eggs from the farms showed higher contamination with pathogenic E. coli than eggs from the retail outlets while the reverse was the case for Salmonella species even though they were not significant (p>0.05). The organisms obtained showed a multiple drug resistance. They were completely resistant to nitrofurantoin, sulfamethoxazole/trimethoprim, penicillin G and oxacillin. In addition to these, Salmonella spp. also showed 100% resistance to tetracycline. The pathogenic E. coli isolates obtained were 100% susceptible to gentamicin, neomycin, ciprofloxacin, and amoxicillin-clavulanic acid while Salmonella spp. showed 100% susceptibility to erythromycin, neomycin, and rifampicin. Both organisms showed varying degrees of resistance to streptomycin, amoxicillin, vancomycin, and doxycycline. Conclusion: From the results of the study, it can be concluded that the raw table eggs marketed for human consumption in Enugu State, Nigeria is contaminated with pathogenic E. coli and Salmonella species that showed multiple drug resistance to antimicrobial agents commonly used in veterinary and human practice. PMID:27956787

Occurrence and antimicrobial resistance of pathogenic Escherichia coli and Salmonella spp. in retail raw table eggs sold for human consumption in Enugu state, Nigeria.

PubMed

Okorie-Kanu, O Josephine; Ezenduka, E Vivienne; Okorie-Kanu, C Onwuchokwe; Ugwu, L Chinweokwu; Nnamani, U John

2016-11-01

This study was conducted to investigate the occurrence of pathogenic Escherichia coli and Salmonella species in retail raw table eggs sold for human consumption in Enugu State and to determine the resistance of these pathogens to antimicrobials commonly used in human and veterinary practices in Nigeria. A total of 340 raw table eggs comprising 68 composite samples (5 eggs per composite sample) were collected from five selected farms (13 composite samples from the farms) and 10 retail outlets (55 composite samples from the retail outlets) in the study area over a period of 4-month (March-June, 2014). The eggs were screened for pathogenic E. coli and Salmonella species following standard procedures within 24 h of sample collection. Isolates obtained were subjected to in-vitro antimicrobial susceptibility test with 15 commonly used antimicrobials using the disk diffusion method. About 37 (54.4%) and 7 (10.3%) of the 68 composite samples were positive for pathogenic E. coli and Salmonella species, respectively. The shells showed significantly higher (p<0.05) contaminations than the contents for both microorganisms. The eggs from the farms showed higher contamination with pathogenic E. coli than eggs from the retail outlets while the reverse was the case for Salmonella species even though they were not significant (p>0.05). The organisms obtained showed a multiple drug resistance. They were completely resistant to nitrofurantoin, sulfamethoxazole/trimethoprim, penicillin G and oxacillin. In addition to these, Salmonella spp. also showed 100% resistance to tetracycline. The pathogenic E. coli isolates obtained were 100% susceptible to gentamicin, neomycin, ciprofloxacin, and amoxicillin-clavulanic acid while Salmonella spp. showed 100% susceptibility to erythromycin, neomycin, and rifampicin. Both organisms showed varying degrees of resistance to streptomycin, amoxicillin, vancomycin, and doxycycline. From the results of the study, it can be concluded that the raw table eggs marketed for human consumption in Enugu State, Nigeria is contaminated with pathogenic E. coli and Salmonella species that showed multiple drug resistance to antimicrobial agents commonly used in veterinary and human practice.

Consequences of switching from a fixed 2 : 1 ratio of amoxicillin/clavulanate (CLSI) to a fixed concentration of clavulanate (EUCAST) for susceptibility testing of Escherichia coli.

PubMed

Leverstein-van Hall, Maurine A; Waar, Karola; Muilwijk, Jan; Cohen Stuart, James

2013-11-01

The CLSI recommends a fixed 2 : 1 ratio of co-amoxiclav for broth microdilution susceptibility testing of Enterobacteriaceae, while EUCAST recommends a fixed 2 mg/L clavulanate concentration. The aims of this study were: (i) to determine the influence of a switch from CLSI to EUCAST methodology on Escherichia coli susceptibility rates; (ii) to compare susceptibility results obtained using EUCAST-compliant microdilution with those from disc diffusion and the Etest; and (iii) to evaluate the clinical outcome of patients with E. coli sepsis treated with co-amoxiclav in relation to the susceptibility results obtained using either method. Resistance rates were determined in three laboratories that switched from CLSI to EUCAST cards with the Phoenix system (Becton Dickinson) as well as in 17 laboratories that continued to use CLSI cards with the VITEK 2 system (bioMérieux). In one laboratory, isolates were simultaneously tested by both the Phoenix system and either disc diffusion (n = 471) or the Etest (n = 113). Medical and laboratory records were reviewed for E. coli sepsis patients treated with co-amoxiclav monotherapy. Only laboratories that switched methodology showed an increase in resistance rates - from 19% in 2010 to 31% in 2011 (P < 0.0001). All isolates that tested susceptible by microdilution were also susceptible by disc diffusion or the Etest, but of 326 isolates that tested resistant by microdilution, 43% and 59% tested susceptible by disc diffusion and the Etest, respectively. Among the 89 patients included there was a better correlation between clinical response and measured MICs using the Phoenix system than the Etest. EUCAST methodology resulted in higher co-amoxiclav E. coli resistance rates than CLSI methodology, but correlated better with clinical outcome. EUCAST-compliant microdilution and disc diffusion provided discrepant results.

Characterization of Escherichia coli O78 from an outbreak of septicemia in lambs in Norway.

PubMed

Kjelstrup, Cecilie K; Arnesen, Lotte P Stenfors; Granquist, Erik G; L'Abée-Lund, Trine M

2013-09-27

The aim of the study was to characterize isolates of Escherichia coli from an outbreak of septicemia in a Norwegian sheep flock in 2008 with emphasis on virulence, serological grouping, phylogenicity and homology. Six E. coli isolates from succumbed neonatal lambs and four E. coli isolates collected from healthy individuals were analyzed by Pulsed-Field Gel Electrophoresis (PFGE), miniaturized microarray, and polymerase chain reaction (PCR). The septicemic E. coli isolates showed identical pulsotypes (PTs), and belonged to serogroup O78, phylogenetic group A, and MLST ST 369. The virulence genes f17G, bmaE, afaE-VIII, ireA, iroN and iss were detected in the septicemic isolates. The results showed that the E. coli isolates from the septicemic outbreak had a clonal appearance, thus likely originating from a common source. The clone carried genes important for virulence, however, a significant explanation for the high pathogenicity was not revealed. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparative genomics and transcriptomics of Escherichia coli isolates carrying virulence factors of both enteropathogenic and enterotoxigenic E. coli.

PubMed

Hazen, Tracy H; Michalski, Jane; Luo, Qingwei; Shetty, Amol C; Daugherty, Sean C; Fleckenstein, James M; Rasko, David A

2017-06-14

Escherichia coli that are capable of causing human disease are often classified into pathogenic variants (pathovars) based on their virulence gene content. However, disease-associated hybrid E. coli, containing unique combinations of multiple canonical virulence factors have also been described. Such was the case of the E. coli O104:H4 outbreak in 2011, which caused significant morbidity and mortality. Among the pathovars of diarrheagenic E. coli that cause significant human disease are the enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). In the current study we use comparative genomics, transcriptomics, and functional studies to characterize isolates that contain virulence factors of both EPEC and ETEC. Based on phylogenomic analysis, these hybrid isolates are more genomically-related to EPEC, but appear to have acquired ETEC virulence genes. Global transcriptional analysis using RNA sequencing, demonstrated that the EPEC and ETEC virulence genes of these hybrid isolates were differentially-expressed under virulence-inducing laboratory conditions, similar to reference isolates. Immunoblot assays further verified that the virulence gene products were produced and that the T3SS effector EspB of EPEC, and heat-labile toxin of ETEC were secreted. These findings document the existence and virulence potential of an E. coli pathovar hybrid that blurs the distinction between E. coli pathovars.

High Frequency of Diarrheagenic Escherichia coli in HIV-Infected Patients and Patients with Thalassemia in Kerman, Iran.

PubMed

Alizade, Hesam; Sharifi, Hamid; Naderi, Zahedeh; Ghanbarpour, Reza; Bamorovat, Mehdi; Aflatoonian, Mohammad Reza

This study was conducted on patients with thalassemia and HIV-infected patients to determine the frequency of diarrheagenic Escherichia coli in Kerman, Iran. We analyzed 68 and 49 E coli isolates isolated from healthy fecal samples of patients with thalassemia and HIV-infected patients, respectively. The E coli isolates were studied using a multiplex polymerase chain reaction to identify the enterotoxigenic E coli (ETEC), enterohemorrhagic E coli (EHEC), and enteropathogenic E coli (EPEC) groups. Statistical analysis was carried out to determine the correlation of diarrheagenic E coli between HIV-infected patients and patients with thalassemia using Stata 11.2 software. The frequency of having at least 1 diarrheagenic E coli was more common in patients with thalassemia (67.64%) than in HIV-infected patients (57.14%; P = .25), including ETEC (67.64% versus 57.14%), EHEC (33.82% versus 26.53%), and EPEC (19.11% versus 16.32%). The results of this study indicate that ETEC, EHEC, and EPEC pathotypes are widespread among diarrheagenic E coli isolates in patients with thalassemia and HIV-infected patients.

blaNDM-21, a new variant of blaNDM in an Escherichia coli clinical isolate carrying blaCTX-M-55 and rmtB.

PubMed

Liu, Lu; Feng, Yu; McNally, Alan; Zong, Zhiyong

2018-06-14

New Delhi MBL (NDM) is a type of carbapenemase; 20 variants of NDM have been identified to date. We have found a new variant of NDM, NDM-21, and describe it here. A carbapenem-resistant Escherichia coli was subjected to WGS using an Illumina X10 sequencer to identify the antimicrobial resistance genes and its ST. The gene encoding the new variant of NDM was cloned into E. coli DH5α, with blaNDM-5 being cloned as the control. Transformants were tested for susceptibility to carbapenems. Mating was performed to obtain the plasmid carrying the new blaNDM gene and the complete plasmid sequence was obtained using long-read MinION sequencing. The E. coli isolate belonged to ST617 and phylogenetic group A. It had a gene encoding NDM-21, a new NDM variant. NDM-21 differs from NDM-5 by a Gly-to-Ser amino acid substitution at position 69 (G69S). NDM-21 retains the same activity against carbapenems as NDM-5. blaNDM-21 is carried by a 46.1 kb IncX3 plasmid, which is self-transmissible, and is located in a complex genetic context as blaNDM-5. The isolate also carried blaCTX-M-55, which encodes an ESBL conferring resistance to aztreonam (which completed its resistance to all clinically available β-lactams), and rmtB, which mediates high-level resistance to aminoglycosides, on an IncFII plasmid. A new NDM variant has been identified and blaNDM-21 has evolved from blaNDM-5 on an IncX3 plasmid.

Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana

PubMed Central

Rasmussen, Mette Marie; Opintan, Japheth A.; Frimodt-Møller, Niels; Styrishave, Bjarne

2015-01-01

The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified as E. coli using MALDI-ToF. Of these 109 isolates were from meat whereas the remaining 44 were isolated from the cloaca of locally reared live chickens. Antimicrobial susceptibility test was done on the identified E. coli isolates. Additionally, beta-lactamases production (ESBL and/or AmpC) were phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP) E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported chickens (tetracycline 88.9% vs. 57.5%, sulphonamide 75.0% vs. 46.6%, ampicillin 69.4% vs. 61.6% and trimethoprim 66.7% vs. 38.4%). Beta-lactamase production was found in 29 E. coli meat isolates, with 56.9% of them being multiple drug resistant (≥ 3). The predominant phylogroup identified was B1 followed by A and D, with similar distribution among the isolates from meat of locally reared chickens and imported chickens. Beta-lactamase producing genotype bla CTX-M-15 (50%; 10/20) was the most frequently drug resistant gene detected. More BLP E. coli isolates were found in imported chicken meat compared to locally reared chickens, demonstrating that these isolates may be spreading through food trade. In conclusion, both imported and locally produced chicken meats are potential sources for human exposure to BLP E. coli. PMID:26461270

Beta-Lactamase Producing Escherichia coli Isolates in Imported and Locally Produced Chicken Meat from Ghana.

PubMed

Rasmussen, Mette Marie; Opintan, Japheth A; Frimodt-Møller, Niels; Styrishave, Bjarne

2015-01-01

The use of antibiotics in food animals is of public health concern, because resistant zoonotic pathogens can be transmitted to humans. Furthermore, global trade with food may rapidly spread multi-resistant pathogens between countries and even continents. The purpose of the study was to investigate whether imported chicken meat and meat from locally reared chicken are potential sources for human exposure to multi resistant Escherichia coli isolates. 188 samples from imported and locally produced chicken meat were sampled and analyzed. 153 bacteria isolates were successfully cultured and identified as E. coli using MALDI-ToF. Of these 109 isolates were from meat whereas the remaining 44 were isolated from the cloaca of locally reared live chickens. Antimicrobial susceptibility test was done on the identified E. coli isolates. Additionally, beta-lactamases production (ESBL and/or AmpC) were phenotypically confirmed on all isolates showing resistance to cefpodoxime. Beta-lactamase producing (BLP) E. coli meat isolates were further genotyped. Antimicrobial resistance to four antibiotic markers with highest resistance was detected more frequently in isolates from local chickens compared to imported chickens (tetracycline 88.9% vs. 57.5%, sulphonamide 75.0% vs. 46.6%, ampicillin 69.4% vs. 61.6% and trimethoprim 66.7% vs. 38.4%). Beta-lactamase production was found in 29 E. coli meat isolates, with 56.9% of them being multiple drug resistant (≥ 3). The predominant phylogroup identified was B1 followed by A and D, with similar distribution among the isolates from meat of locally reared chickens and imported chickens. Beta-lactamase producing genotype blaCTX-M-15 (50%; 10/20) was the most frequently drug resistant gene detected. More BLP E. coli isolates were found in imported chicken meat compared to locally reared chickens, demonstrating that these isolates may be spreading through food trade. In conclusion, both imported and locally produced chicken meats are potential sources for human exposure to BLP E. coli.

Virulence Factors of Escherichia coli Isolated From Female Reproductive Tract Infections and Neonatal Sepsis

PubMed Central

Cook, Susan W.; Hammill, Hunter A.

2001-01-01

Objective: The presence of enterobacteria such as Escherichia coli in the vagina of normal women is not synonymous with infection. However, vaginal E. coli may also cause symptomatic infections. We examined bacterial virulenceproperties that may promote symptomatic female reproductive tract infections (RTI) and neonatal sepsis. Methods: E. coli isolated as the causative agent from cases of vaginitis (n = 50), tubo-ovarian abscess (n = 45) and neonatal sepsis (n = 45) was examined for selected phenotypic and genetic virulence properties. Results were compared with the frequency of the same properties among fecal E. coli not associated with disease. Results: A significantly greater proportion of infection E. coli exhibited D-mannose resistant hemagglutination compared with fecal E. coli (p < 0.01). This adherence phenotype was associated with the presence of P fimbriae (pap) genes which were also significantly more prevalent among isolates from all three infection sites (p < 0.01). The majority of pap+ isolates contained the papG3 allele (Class II) regardless of infection type. Increased frequency of Type 1C genes among vaginitis and abscess isolates was also noted. No significant differences in frequency of other bacterial adherence genes, fim, sfa, uca (gaf) or dra were observed. E. coli associated with vaginitis was significantly more likely to be hemolytic ( HIy+) than were fecal isolates (p < 0.05). The HIy+ phenotype was also more prevalent among tubo-ovarian abscess and neonatal sepsis isolates (p < 0.08). Conclusions: E. coli isolated from female RTI and neonatal sepses possess unique properties that may enhance their virulence. These properties are similar to those associated with other E. coli extra-intestinal infections, indicating that strategies such as vaccination or bacterial interference that may be developed against urinary tract infections (UTI) and other E. coli extra-intestinal infections may also prevent selected female RTI. PMID:11916176

Random breakup of microdroplets for single-cell encapsulation

NASA Astrophysics Data System (ADS)

Um, Eujin; Lee, Seung-Goo; Park, Je-Kyun

2010-10-01

Microfluidic droplet-based technology enables encapsulation of cells in the isolated aqueous chambers surrounded by immiscible fluid but single-cell encapsulation efficiency is usually less than 30%. In this letter, we introduce a simple microgroove structure to break droplets into random sizes which further allows collecting of single-cell [Escherichia coli (E. coli)] containing droplets by their size differences. Pinched-flow separation method is integrated to sort out droplets of certain sizes which have high probability of containing one cell. Consequently, we were able to obtain more than 50% of droplets having single E. coli inside, keeping the proportion of multiple-cell containing droplets less than 16%.

Genotypic analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs in Iran.

PubMed

Ghanbarpour, Reza; Askari, Nasrin; Ghorbanpour, Masoud; Tahamtan, Yahya; Mashayekhi, Khoobyar; Afsharipour, Narjes; Darijani, Nasim

2017-03-01

The aim of the present study was to determine the analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs. Two hundred ninety E. coli isolates were recovered from 300 rectal swabs of diarrheic lambs and were confirmed by biochemical tests. The pathotype determination was done according to the presence of genes including f5, f41, LTI, STI, bfp, ipaH, stx 1 , stx 2 , eae, ehlyA, cnf 1 , cnf 2 , cdIII, cdIV, and f17 by PCR method. Sixty-six isolates (23.72%) possessed the STI gene and categorized into entrotoxigenic E. coli (ETEC). Nine isolates (3.1%) and five isolates (1.72%) were positive for the cnf1 and cnf2 genes which categorized into necrotoxic E. coli (NTEC). Hundred and seventeen isolates (40.34%) harbored stx 1 and/or stx 2 and classified as Shiga toxin-producing E. coli (STEC). Thirteen isolates (4.48%) were assigned to atypical entropathogenic E. coli (aEPEC) and possessed eae gene. Two isolates (0.68%) were positive for ipaH gene and were assigned to entroinvasive E. coli (EIEC). Statistical analysis showed a specific association between eae gene and STEC pathotype (P < 0.0001). The most prevalent resistance was observed against lincomycin (96.5%) and the lowest resistance was against kanamycine (56.02%), respectively. The high prevalence of STEC and ETEC indicates that diarrheic lambs represent an important reservoir for humans. ETEC may play an important role for frequent occurrence of diarrhea in lambs observed in this region. Due to high antibiotic resistance, appropriate control should be implemented in veterinary medicine to curb the development of novel resistant isolates.

The role of doxycycline in the therapy of multidrug-resistant E. coli - an in vitro study.

PubMed

Lai, Chih-Cheng; Chen, Chi-Chung; Huang, Hui-Ling; Chuang, Yin-Ching; Tang, Hung-Jen

2016-08-18

This study assessed the in vitro antibacterial activity of combinations of amikacin and doxycycline or tigecycline against multidrug-resistant E. coli isolates. Twenty-four different pulsotypes, including 10 extended-spectrum β-lactamase (ESBL)-, 10 carbapenem-resistant, 2 New Delhi Metallo-beta-lactamase (NDM)- and 2 Klebsiella pneumoniae carbapenemase (KPC)-E. coli isolates were collected. All 24 isolates were susceptible to amikacin and tigecycline. Only 30% of ESBL and 50% of carbapenem-resistant E. coli were susceptible to doxycycline. Both of the NDM-E. coli had a MIC of 64 μg/ml. The checkerboard method showed that for the ESBL- and carbapenem-resistant E. coli, the synergistic effects of amikacin/doxycycline were 80% and 90%, respectively. For the two KPC- and two NDM-E. coli, the FIC index of amikacin/doxycycline were 0.5/0.375 and 0.5/0.281, respectively. For the ESBL- and carbapenem-resistant E. coli isolates, the combinations of amikacin and doxycycline exhibited synergistic activities against 80%, and 80% and 10% vs 60%, and 80% and 10% of the isolates at concentrations of 1x, 1/2x and 1/4xMIC, respectively. The synergistic effect seems to be similar for doxycycline and tigecycline based combinations with amikacin. In conclusion, the antibacterial activity of doxycycline can be enhanced by the addition of amikacin and is observed against most multidrug-resistant E. coli isolates.

Occurrence, virulence genes and antibiotic resistance of Escherichia coli O157 isolated from raw bovine, caprine and ovine milk in Greece.

PubMed

Solomakos, Nikolaos; Govaris, Alexandros; Angelidis, Apostolos S; Pournaras, Spyros; Burriel, Angeliki Rothi; Kritas, Spyridon K; Papageorgiou, Demetrios K

2009-12-01

The examination of 2005 raw bovine (n = 950), caprine (n = 460) and ovine (n = 595) bulk milk samples collected throughout several regions in Greece for the presence of Escherichia coli serogroup O157 resulted in the isolation of 29 strains (1.4%) of which 21 were isolated from bovine (2.2%), 3 from caprine (0.7%) and 5 from ovine (0.8%) milk. Out of the 29 E. coli O157 isolates, only 12 (41.4%) could be classified as Shiga-toxigenic based on immunoassay and PCR results. All 12 Shiga-toxigenic E. coli serogroup O157 isolates belonged to the E. coli O157:H7 serotype. All except one of the 12 Shiga-toxin positive isolates were stx(2)-positive, five of which were also stx(1)-positive. The remaining isolate was positive only for the stx(1) gene. All stx-positive isolates (whether positive for stx(1), stx(2) or stx(1) and stx(2)) were also PCR-positive for the eae and ehxA genes. The remaining 17 E. coli O157 isolates (58.6%) were negative for the presence of the H7 flagellar gene by PCR, tested negative for Shiga-toxin production both by immunoassay and PCR, and among these, only four and three strains were PCR-positive for the eae and ehxA genes, respectively. All 29 E. coli O157 isolates displayed resistance to a wide range of antimicrobials, with the stx-positive isolates being, on average, resistant to a higher number of antibiotics than those which were stx-negative.

Isolation and evaluation of cocktail phages for the control of multidrug-resistant Escherichia coli serotype O104: H4 and E. coli O157: H7 isolates causing diarrhea.

PubMed

Safwat Mohamed, Doaa; Farouk Ahmed, Eman; Mohamed Mahmoud, Abobakr; Abd El-Baky, Rehab Mahmoud; John, James

2018-02-01

Escherichia coli serotype O157: H7 and E. coli O104: H4 are well known foodborne pathogens causing sever enteric illness. Using bacteriophages as biocontrol agents of some foodborne pathogens and multidrug-resistant (MDR) bacteria has a great attention nowadays. This study aims to test the effect of cocktail phages on the growth of some foodborne pathogens and MDR E. coli. Routine conventional PCR was used to confirm the identification of E. coli isolates. Double-layered culture technique was used to isolate phages from sewage water. Morphology of bacteriophage was described using transmission electron microscopy, and spot test was performed to determine host range of the phage cocktail. Phage cocktail of Siphoviridae and Podoviridae family infecting E. coli O157: H7, E. coli O104: H4 and untypeable E. coli (neither O157 nor O104) has been isolated from sewage water. Phage cocktail showed both lytic and lysogenic activity. Lytic activity was observed against E. coli O157: H7, E. coli O104: H4 isolates, Staphylococcus. aureus ATCC6538 and Pseudomonas aeruginosa ATCC 10145, while the lysogenic activity was observed against the untypeable strain. The tested phage cocktail showed a promising inhibitory action on E. coli O157: H7 and O104: H4, S. aureus ATCC6538 and P. aeruginosa ATCC 10145, suggesting the possibility of its use as a biocontrol tool or as natural food preservatives for many food products. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Genotypic characterization of Escherichia coli O157:H7 isolates from different sources in the North-West Province, South Africa, using enterobacterial repetitive intergenic consensus PCR analysis.

PubMed

Ateba, Collins Njie; Mbewe, Moses

2014-05-30

In many developing countries, proper hygiene is not strictly implemented when animals are slaughtered and meat products become contaminated. Contaminated meat may contain Escherichia coli (E. coli) O157:H7 that could cause diseases in humans if these food products are consumed undercooked. In the present study, a total of 94 confirmed E. coli O157:H7 isolates were subjected to the enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR) typing to generate genetic fingerprints. The ERIC fragments were resolved by electrophoresis on 2% (w/v) agarose gels. The presence, absence and intensity of band data were obtained, exported to Microsoft Excel (Microsoft Office 2003) and used to generate a data matrix. The unweighted pair group method with arithmetic mean (UPGMA) and complete linkage algorithms were used to analyze the percentage of similarity and matrix data. Relationships between the various profiles and/or lanes were expressed as dendrograms. Data from groups of related lanes were compiled and reported on cluster tables. ERIC fragments ranged from one to 15 per isolate, and their sizes varied from 0.25 to 0.771 kb. A large proportion of the isolates produced an ERIC banding pattern with three duplets ranging in sizes from 0.408 to 0.628 kb. Eight major clusters (I-VIII) were identified. Overall, the remarkable similarities (72% to 91%) between the ERIC profiles for the isolate from animal species and their corresponding food products indicated some form of contamination, which may not exclude those at the level of the abattoirs. These results reveal that ERIC PCR analysis can be reliable in comparing the genetic profiles of E. coli O157:H7 from different sources in the North-West Province of South Africa.

Antibiotic resistance pattern and plasmid profiling of thermotolerant Escherichia coli isolates in drinking water.

PubMed

Subba, P; Joshi, D R; Bhatta, D R

2013-01-01

Antibiotic resistant Escherichia coli is potential source of transmission of resistance to other water borne pathogens where plasmid borne resistance is most significant. Drinking water samples were collected from different water sources: that is to say- tap, well and spring from different places of Kathmandu where E. coli and thermotolerant E. coli were isolated using membrane filtration technique. Antibiotic susceptibility was determined using a modified Kirby Bauer disc diffusion method and thermotolerant E. coli isolates from tap water were subjected for plasmid profiling. Type of water sources were not associated with the presence of coliform (P=0.155) and thermotolerant coliform (P=0.235) but the significant association was observed in thermotolerant coliform and thermotolerant E. coli for all sources tap (P=0.029), well (P=0.028), spring (P=0.05) but total coliform and E. coli association was found for well (P=0.01). All E. coli and thermotolerant E. coli isolates were susceptible to Ofloxacin, Chloramphenicol and Cotrimixazole. Resistance to Cefexime, Amikacin, Nalidixic acid, Amoxicillin, Tetracycline were 17 (54.8%), 9 (29%), 11 (35.5%), 25 (80.6%), 29 (93.5%) and 19 (57.6%), 12 (36.4%), 13 (39.4%), 31 (94%), 33 (100%) was observed in E. coli and thermotolerant E. coli respectively where 25 (75.8%) thermotolerant E. coli and 22 (70.9%) E. coli were observed with multiple drug resistance patterns. Single band of plasmid were observed in three MDRs and one non-MDR isolates and size varied from 2kb to >10kb. All Nalidixic acid resistant thermotolerant E. coli were found to harbor a plasmid. Presence of plasmid in Nalidixic acid resistant thermotolerant E. coli heightens public health issue and the need of monitoring Quinolone resistance bacteria in environment.

In vitro bactericidal activity of enrofloxacin against gyrA mutant and qnr-containing Escherichia coli isolates from animals.

PubMed

Cengiz, M; Sahinturk, P; Sonal, S; Buyukcangaz, E; Sen, A; Arslan, E

2013-05-04

The objective of this work was to investigate the bactericidal activity of enrofloxacin against gyrA mutant and qnr-containing Escherichia coli isolates from animals. The minimum inhibitory concentrations (MICs) of gyrA mutant and qnr-containing E coli isolates ranged from 1 µg/ml to 32 µg/ml for enrofloxacin. Time-kill experiments were performed using selected E coli isolates. For the time-kill experiments, the colony counts were determined by plating each diluted sample onto plate count agar and an integrated pharmacokinetic/pharmacodynamics area measure (log ratio area) was applied to the colony-forming units (cfu) data. In general, enrofloxacin exhibited bactericidal activity against all the gyrA mutant E coli isolates at all concentrations greater than four times the MIC. However, the bactericidal activity of enrofloxacin for all the qnr-containing E coli isolates was less dependent on concentration. The results of the present study indicated that the genetic mechanism of resistance might account for the different bactericidal activities of enrofloxacin observed for the gyrA mutant and the qnr-containing E coli isolates. Therefore, in addition to MIC assays, genetic mechanism-based pharmacodynamic models should be used to provide accurate predictions of the effects of drugs on resistant bacteria.

Prevalence and characterization of antimicrobial-resistant Escherichia coli isolated from conventional and organic vegetables.

PubMed

Kim, Sara; Woo, Gun-Jo

2014-10-01

To compare the characteristics and to identify the epidemiological relationships of Escherichia coli isolated from organic and conventional vegetables, the antimicrobial resistance and genetic properties of E. coli were investigated from 2010 to 2011. E. coli was isolated from 1 of 111 (0.9%) organic vegetables and from 20 of 225 (8.9%) conventional vegetables. The majority of strains were isolated from the surrounding farming environment (n=27/150 vs. 49/97 in organic vs. conventional samples). The majority of the vegetable strains were isolated from the surrounding farming environments. E. coli isolated from organic vegetables showed very low antimicrobial resistance rates except for cephalothin, ranging from 0% to 17.9%, while the resistance rates to cephalothin (71%) were extremely high in both groups. E. coli isolates expressed various resistance genes, which most commonly included blaTEM, tet(A), strA, strB, and qnrS. However, none of the isolates harbored tet(D), tet(E), tet(K), tet(L), tet(M), or qnrA. The transferability of tet gene, tet(A), and tet(B) was identified in tetracycline-resistant E. coli, and the genetic relationship was confirmed in a few cases from different sources. With regard to the lower antimicrobial resistance found in organic produce, this production mode seems able to considerably reduce the selection of antimicrobial-resistant bacteria on vegetables.

Comparative Genome Analysis of Extended-Spectrum-β-Lactamase-Producing Escherichia coli Sequence Type 131 Strains from Nepal and Japan

PubMed Central

Miyoshi-Akiyama, Tohru; Sherchan, Jatan Bahadur; Doi, Yohei; Nagamatsu, Maki; Sherchand, Jeevan B.; Tandukar, Sarmila; Ohmagari, Norio; Kirikae, Teruo; Ohara, Hiroshi

2016-01-01

ABSTRACT The global spread of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli (ESBL-E. coli) has largely been driven by the pandemic sequence type 131 (ST131). This study aimed to determine the molecular epidemiology of their spread in two Asian countries with contrasting prevalence. We conducted whole-genome sequencing (WGS) of ESBL-E. coli ST131 strains collected prospectively from Nepal and Japan, two countries in Asia with a high and low prevalence of ESBL-E. coli, respectively. We also systematically compared these genomes with those reported from other regions using publicly available WGS data for E. coli ST131 strains. Further, we conducted phylogenetic analysis of these isolates and all genome sequence data for ST131 strains to determine sequence diversity. One hundred five unique ESBL-E. coli isolates from Nepal (February 2013 to July 2013) and 76 isolates from Japan (October 2013 to September 2014) were included. Of these isolates, 54 (51%) isolates from Nepal and 11 (14%) isolates from Japan were identified as ST131 by WGS. Phylogenetic analysis based on WGS suggested that the majority of ESBL-E. coli ST131 isolates from Nepal clustered together, whereas those from Japan were more diverse. Half of the ESBL-E. coli ST131 isolates from Japan belonged to virotype C, whereas half of the isolates from Nepal belonged to a virotype other than virotype A, B, C, D, or E (A/B/C/D/E). The dominant sublineage of E. coli ST131 was H30Rx, which was most prominent in ESBL-E. coli ST131 isolates from Nepal. Our results revealed distinct phylogenetic characteristics of ESBL-E. coli ST131 spread in the two geographical areas of Asia, indicating the involvement of multiple factors in its local spread in each region. IMPORTANCE The global spread of ESBL-E. coli has been driven in large part by pandemic sequence type 131 (ST131). A recent study suggested that, within E. coli ST131, certain sublineages have disseminated worldwide with little association with their geographical origin, highlighting the complexity of the epidemiology of this pandemic clone. ST131 bacteria have also been classified into four virotypes based on the distribution of certain virulence genes. Information on virotype distribution in Asian ST131 strains is limited. We conducted whole-genome sequencing of ESBL-E. coli ST131 strains collected in Nepal and Japan, two Asian countries with a high and low prevalence of ESBL-E. coli, respectively. We systematically compared these ST131 genomes with those reported from other regions to gain insights into the molecular epidemiology of their spread and found the distinct phylogenetic characteristics of the spread of ESBL-E. coli ST131 in these two geographical areas of Asia. PMID:27830191

Class 1 integrons and plasmid-mediated multiple resistance genes of the Campylobacter species from pediatric patient of a university hospital in Taiwan.

PubMed

Chang, Yi-Chih; Tien, Ni; Yang, Jai-Sing; Lu, Chi-Cheng; Tsai, Fuu-Jen; Huang, Tsurng-Juhn; Wang, I-Kuan

2017-01-01

The Campylobacter species usually causes infection between humans and livestock interaction via livestock breeding. The studies of the Campylobacter species thus far in all clinical isolates were to show the many kinds of antibiotic phenomenon that were produced. Their integrons cause the induction of antibiotic resistance between bacterial species in the Campylobacter species. The bacterial strains from the diarrhea of pediatric patient which isolated by China Medical University Hospital storage bank. These isolates were identified by MALDI-TOF mass spectrometry. The anti-microbial susceptibility test showed that Campylobacter species resistant to cefepime, streptomycin, tobramycin and trimethoprim/sulfamethoxazole (all C. jejuni and C. coli isolates), ampicillin (89% of C. jejuni ; 75% of C. coli ), cefotaxime (78% of C. jejuni ; 100% of C. coli ), nalidixic acid (78% of C. jejuni ; 100% of C. coli ), tetracycline (89% of C. jejuni ; 25% C. coli ), ciprofloxacin (67% of C. jejuni ; 50% C. coli ), kanamycin (33% of C. jejuni ; 75% C. coli ) and the C. fetus isolate resisted to ampicillin, cefotaxime, nalidixic acid, tetracycline, ciprofloxacin, kanamycin by disc-diffusion method. The effect for ciprofloxacin and tetracycline of the Campylobacter species was tested using an E-test. The tet, erm , and integron genes were detected by PCR assay. According to the sequencing analysis (type I: dfr12 - gcuF - aadA2 genes and type II: dfrA7 gene), the cassette type was identified. The most common gene cassette type (type I: 9 C. jejuni and 2 C. coli isolates; type II: 1 C. coli isolates) was found in 12 class I integrase-positive isolates. Our results suggested an important information in the latency of Campylobacter species with resistance genes, and irrational antimicrobial use should be concerned.

Multidrug-resistant pathogenic Escherichia coli isolated from wild birds in a veterinary hospital.

PubMed

Borges, C A; Beraldo, L G; Maluta, R P; Cardozo, M V; Barboza, K B; Guastalli, E A L; Kariyawasam, S; DebRoy, C; Ávila, F A

2017-02-01

Wild birds are carriers of Escherichia coli. However, little is known about their role as reservoirs for extra-intestinal pathogenic E. coli (ExPEC). In this work we investigated E. coli strains carrying virulence genes related to human and animal ExPEC isolated from free-living wild birds treated in a veterinary hospital. Multidrug resistance was found in 47.4% of the strains, but none of them were extended-spectrum beta-lactamase producers. Not only the virulence genes, but also the serogroups (e.g. O1 and O2) detected in the isolates of E. coli have already been implicated in human and bird diseases. The sequence types detected were also found in wild, companion and food animals, environmental and human clinical isolates in different countries. Furthermore, from the 19 isolates, 17 (89.5%) showed a degree of pathogenicity on an in vivo infection model. The isolates showed high heterogeneity by pulsed-field gel electrophoresis indicating that E. coli from these birds are clonally diverse. Overall, the results showed that wild birds can be reservoirs and/or vectors of highly pathogenic and multidrug-resistant E. coli that have the potential to cause disease in humans and poultry.

Prevalence, distribution, and diversity of Escherichia coli in plants manufacturing goat milk powder in Shaanxi, China.

PubMed

Xi, Meili; Feng, Yuqing; Li, Qiong; Yang, Qinnan; Zhang, Baigang; Li, Guanghui; Shi, Chao; Xia, Xiaodong

2015-04-01

The aim of the study was to investigate the prevalence, distribution, and diversity of Escherichia coli in goat-milk-powder plants in Shaanxi, China. Three plants manufacturing goat milk powder in Shaanxi province were visited once for sampling during 2012 and 2013. Samples were taken for isolation of E. coli. Isolates were characterized by antimicrobial susceptibility testing and detection of virulence genes. All isolates were further examined by pulsed-field gel electrophoresis analysis. In total, 53 E. coli strains were isolated from 32 positive samples out of 534 samples. Among E. coli isolates, resistance was most frequently observed to trimethoprim-sulfamethoxazole (75.5%), whereas all isolates were sensitive to gatifloxacin, kanamycin, amikacin, and amoxicillin-clavulanate. The 6 virulence genes of pathogenic E. coli were not detected. Pulsed-field gel electrophoresis results showed that E. coli strains in plants were genetically diverse and milk storage tank could be an important contamination source. This study could provide useful information for plants manufacturing goat milk powder to establish proper management practices that help minimize the chance of microbial contamination. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Longitudinal Study of Fecal Shedding of Escherichia coli O157:H7 in Feedlot Cattle: Predominance and Persistence of Specific Clonal Types despite Massive Cattle Population Turnover

PubMed Central

LeJeune, J. T.; Besser, T. E.; Rice, D. H.; Berg, J. L.; Stilborn, R. P.; Hancock, D. D.

2004-01-01

Identification of the sources and methods of transmission of Escherichia coli O157:H7 in feedlot cattle may facilitate the development of on-farm control measures for this important food-borne pathogen. The prevalence of E. coli O157:H7 in fecal samples of commercial feedlot cattle in 20 feedlot pens between April and September 2000 was determined throughout the finishing feeding period prior to slaughter. Using immunomagnetic separation, E. coli O157:H7 was isolated from 636 of 4,790 (13%) fecal samples in this study, with highest prevalence earliest in the feeding period. No differences were observed in the fecal or water trough sediment prevalence values of E. coli O157:H7 in 10 pens supplied with chlorinated drinking water supplies compared with nonchlorinated water pens. Pulsed-field gel electrophoresis of XbaI-digested bacterial DNA of the 230 isolates obtained from eight of the pens revealed 56 unique restriction endonuclease digestion patterns (REDPs), although nearly 60% of the isolates belonged to a group of four closely related genetic subtypes that were present in each of the pens and throughout the sampling period. The other REDPs were typically transiently detected, often in single pens and on single sample dates, and in many cases were also closely related to the four predominant REDPs. The persistence and predominance of a few REDPs observed over the entire feeding period on this livestock operation highlight the importance of the farm environment, and not necessarily the incoming cattle, as a potential source or reservoir of E. coli O157:H7 on farms. PMID:14711666

Enteroaggregative Escherichia coli O78:H10, the Cause of an Outbreak of Urinary Tract Infection

PubMed Central

Scheutz, Flemming; Andersen, Rebecca L.; Menard, Megan; Boisen, Nadia; Johnston, Brian; Hansen, Dennis S.; Krogfelt, Karen A.; Nataro, James P.; Johnson, James R.

2012-01-01

In 1991, multiresistant Escherichia coli O78:H10 strains caused an outbreak of urinary tract infections in Copenhagen, Denmark. The phylogenetic origin, clonal background, and virulence characteristics of the outbreak isolates, and their relationship to nonoutbreak O78:H10 strains according to these traits and resistance profiles, are unknown. Accordingly, we extensively characterized 51 archived E. coli O78:H10 isolates (48 human isolates from seven countries, including 19 Copenhagen outbreak isolates, and 1 each of calf, avian, and unknown-source isolates), collected from 1956 through 2000. E. coli O78:H10 was clonally heterogeneous, comprising one dominant clonal group (61% of isolates, including all 19 outbreak isolates) from ST10 (phylogenetic group A) plus several minor clonal groups (phylogenetic groups A and D). All ST10 isolates, versus 25% of non-ST10 isolates, were identified by molecular methods as enteroaggregative E. coli (EAEC) (P < 0.001). Genes present in >90% of outbreak isolates included fimH (type 1 fimbriae; ubiquitous in E. coli); fyuA, traT, and iutA (associated with extraintestinal pathogenic E. coli [ExPEC]); and sat, pic, aatA, aggR, aggA, ORF61, aaiC, aap, and ORF3 (associated with EAEC). An outbreak isolate was lethal in a murine subcutaneous sepsis model and exhibited characteristic EAEC “stacked brick” adherence to cultured epithelial cells. Thus, the 1991 Copenhagen outbreak was caused by a tight, non-animal-associated subset within a broadly disseminated O78:H10 clonal group (ST10; phylogenetic group A), members of which exhibit both ExPEC and EAEC characteristics, whereas O78:H10 isolates overall are phylogenetically diverse. Whether ST10 O78:H10 EAEC strains are both uropathogenic and diarrheagenic warrants further investigation. PMID:22972830

Enteroaggregative Escherichia coli O78:H10, the cause of an outbreak of urinary tract infection.

PubMed

Olesen, Bente; Scheutz, Flemming; Andersen, Rebecca L; Menard, Megan; Boisen, Nadia; Johnston, Brian; Hansen, Dennis S; Krogfelt, Karen A; Nataro, James P; Johnson, James R

2012-11-01

In 1991, multiresistant Escherichia coli O78:H10 strains caused an outbreak of urinary tract infections in Copenhagen, Denmark. The phylogenetic origin, clonal background, and virulence characteristics of the outbreak isolates, and their relationship to nonoutbreak O78:H10 strains according to these traits and resistance profiles, are unknown. Accordingly, we extensively characterized 51 archived E. coli O78:H10 isolates (48 human isolates from seven countries, including 19 Copenhagen outbreak isolates, and 1 each of calf, avian, and unknown-source isolates), collected from 1956 through 2000. E. coli O78:H10 was clonally heterogeneous, comprising one dominant clonal group (61% of isolates, including all 19 outbreak isolates) from ST10 (phylogenetic group A) plus several minor clonal groups (phylogenetic groups A and D). All ST10 isolates, versus 25% of non-ST10 isolates, were identified by molecular methods as enteroaggregative E. coli (EAEC) (P < 0.001). Genes present in >90% of outbreak isolates included fimH (type 1 fimbriae; ubiquitous in E. coli); fyuA, traT, and iutA (associated with extraintestinal pathogenic E. coli [ExPEC]); and sat, pic, aatA, aggR, aggA, ORF61, aaiC, aap, and ORF3 (associated with EAEC). An outbreak isolate was lethal in a murine subcutaneous sepsis model and exhibited characteristic EAEC "stacked brick" adherence to cultured epithelial cells. Thus, the 1991 Copenhagen outbreak was caused by a tight, non-animal-associated subset within a broadly disseminated O78:H10 clonal group (ST10; phylogenetic group A), members of which exhibit both ExPEC and EAEC characteristics, whereas O78:H10 isolates overall are phylogenetically diverse. Whether ST10 O78:H10 EAEC strains are both uropathogenic and diarrheagenic warrants further investigation.

Identification of enteropathogenic Escherichia coli in children with acute diarrheic syndrome from Sucre State, Venezuela.

PubMed

Michelli, Elvia; Millán, Adriana; Rodulfo, Hectorina; Michelli, Mirian; Luiggi, Jesús; Carreño, Numirin; De Donato, Marcos

2016-03-28

Diarrheagenic Escherichia coli is an important causative agent of acute diarrheic syndrome.  To identify clonal groups of enteropathogenic E. coli (EPEC), in 485 children with acute diarrhea aged 0 to 10 years attending health care centers in Arismendi, Benítez and Sucre municipalities, Sucre state, Venezuela, from March to December, 2011.  After obtaining the informed consent, stool samples were collected. Escherichia coli was identified using standard coproculture methods and serology with polyvalent and monovalent antisera. DNA was isolated, and eae (intimin) and bfpA (bundlin) genes were amplified through two multiplex polymerase chain reactions (PCR).  The presence of bacterial infection was determined in 39.6% of coprocultures. The prevalence of E. coli was 54.7%; 82.9% of these isolates were positive by serology for the evaluated serogroups and serotypes, which were mostly identified in children between 0 and 2 years (37.9%); 48.6% of E. coli strains amplified the eae gene; of these, 58.8% were classified as typical EPEC (eae+ y bfp+). EPEC II was the most common serogroup (38.7%), with predominance of typical EPEC (60%). In positive strains for eae gene, the β intimin allele was the most frequently identified (74.5%). Only four strains with O157:H7 serotype were identified, which showed no PCR amplification of the eae and bfpA genes.  This study showed the importance of molecular tests to identify diarrheagenic E. coli strains causing clinical conditions of varying severity.

Analysis of Genome Plasticity in Pathogenic and Commensal Escherichia coli Isolates by Use of DNA Arrays

PubMed Central

Dobrindt, Ulrich; Agerer, Franziska; Michaelis, Kai; Janka, Andreas; Buchrieser, Carmen; Samuelson, Martin; Svanborg, Catharina; Gottschalk, Gerhard; Karch, Helge; Hacker, Jörg

2003-01-01

Genomes of prokaryotes differ significantly in size and DNA composition. Escherichia coli is considered a model organism to analyze the processes involved in bacterial genome evolution, as the species comprises numerous pathogenic and commensal variants. Pathogenic and nonpathogenic E. coli strains differ in the presence and absence of additional DNA elements contributing to specific virulence traits and also in the presence and absence of additional genetic information. To analyze the genetic diversity of pathogenic and commensal E. coli isolates, a whole-genome approach was applied. Using DNA arrays, the presence of all translatable open reading frames (ORFs) of nonpathogenic E. coli K-12 strain MG1655 was investigated in 26 E. coli isolates, including various extraintestinal and intestinal pathogenic E. coli isolates, 3 pathogenicity island deletion mutants, and commensal and laboratory strains. Additionally, the presence of virulence-associated genes of E. coli was determined using a DNA “pathoarray” developed in our laboratory. The frequency and distributional pattern of genomic variations vary widely in different E. coli strains. Up to 10% of the E. coli K-12-specific ORFs were not detectable in the genomes of the different strains. DNA sequences described for extraintestinal or intestinal pathogenic E. coli are more frequently detectable in isolates of the same origin than in other pathotypes. Several genes coding for virulence or fitness factors are also present in commensal E. coli isolates. Based on these results, the conserved E. coli core genome is estimated to consist of at least 3,100 translatable ORFs. The absence of K-12-specific ORFs was detectable in all chromosomal regions. These data demonstrate the great genome heterogeneity and genetic diversity among E. coli strains and underline the fact that both the acquisition and deletion of DNA elements are important processes involved in the evolution of prokaryotes. PMID:12618447

High Prevalence of Escherichia coli-Producing CTX-M-15 Extended-Spectrum Beta-Lactamases in Poultry and Human Clinical Isolates in Romania.

PubMed

Maciuca, Iuliana E; Williams, Nicola J; Tuchilus, Cristina; Dorneanu, Olivia; Guguianu, Eleonora; Carp-Carare, Catalin; Rimbu, Cristina; Timofte, Dorina

2015-12-01

Use of antibiotics in food animals may contribute to development and spread of resistant organisms, particularly so in some countries. The aim of this study was two-fold; first, to establish the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli in chicken production in a region within Romania. Second, to study the relatedness of ESBL-producing E. coli isolates recovered from broilers, abattoir workers where the chickens were slaughtered and from the human clinical specimens from two regional hospitals. The results indicated a very high (69%) rate of carriage of ESBL and AmpC-producing E. coli in chickens with 36% CTX-M producers. Sequencing showed that chickens in Romania have the highest worldwide prevalence (53%) of blaCTX-M-15 reported in poultry E. coli isolates. The majority (53%) of the extended-spectrum cephalosporin-resistant E. coli carried plasmid-mediated blaampC genes, mostly blaCMY-2 type, one of the highest prevalences reported in Europe. The predominant CTX-M type found in the human clinical E. coli isolates was blaCTX-M-15 and most isolates coharbored blaOXA-1, blaTEM, and aac(6')-ib-cr. The majority (60%) of the human clinical isolates belonged to the pandemic virulent clone B2-ST131. The clonal relationship between broiler and the human CTX-M-producing E. coli isolates was assessed by macrorestriction pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), which indicated strain diversity with no common STs found between human and poultry isolates. Moreover, IncI1 was the most prevalent replicon found in broiler ESBL-producing E. coli isolates and also in transconjugants, indicating that plasmids and not clonal spread may play a role in the transfer of blaCTX-M genes. This study identifies a high prevalence of ESBL-producing E. coli from broiler chickens in Romania with a high occurrence incidence of blaCTX-M-15, which reflects the main ESBL type found in human E. coli infections in this country.

Biochemical analysis of metallo-β-lactamase NDM-3 from a multidrug-resistant Escherichia coli strain isolated in Japan.

PubMed

Tada, Tatsuya; Miyoshi-Akiyama, Tohru; Shimada, Kayo; Kirikae, Teruo

2014-06-01

New Delhi metallo-β-lactamase-3 (NDM-3) was identified in a multidrug-resistant Escherichia coli isolate, NCGM77, obtained from the feces of a patient in Japan. The enzymatic activities of NDM-3 against β-lactams were similar to those of NDM-1, although NDM-3 showed slightly lower kcat/Km ratios for all the β-lactams tested except for doripenem. The genetic context for blaNDM-3 was tnpA-blaNDM-3-bleMBL-trpF-dsbC-tnpA-sulI-qacEdeltaI-aadA2-dfrA1, which was present on an approximately 250-kb plasmid. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Asymtomatic bacteriuria in pregnancy: assesment of prevlence, microbial agents and ther antimicrobial sensitivty pattern in Gondar Teaching Hospital, north west Ethiopia.

PubMed

Tadesse, Abilo; Negash, Mekonnen; Ketema, Late Shimeles

2007-04-01

To estimate the prevalence of asymptomatic bacteriuria in pregnant women, identify the frequently isolated uropathogenic bacteria and its antimicrobial sensitivity pattern. This cross-sectional case series study was conducted in antenatal care clinic of Gondar Teaching Hospital from June-Oct., 2001. One hundred and seventy three pregnant women, who met the inclusion criteria, were included in the study after informed consent was obtained Clinical information pertaining to socio demographic data and obstetric history was filled in the questionnaire, pertinent physical examination was done and urine specimen from each candidate was collected and processed following the standard microbiological technique. Majority (70-90%) of the pregnant women were literate, housewives, married and residents of Gondar town. Of all pregnant women included in the study, 96/173 (56%) were multigravida, and 21/173 (12%) had 5 or more pregnancies. The identification rate of significant bacteriuria in the study group was 9.8% (17/173) with higher rate (20.5%) in multiparous mothers. The frequently isolated urinary pathogenic bacteria was E. coli, 47% (8/17), followed by S. aureus 3/17 (18%) and C. freundi 2/17 (12%). The majority of E. coli isolates (50-75%) were resistant to gentamicin, Ampicillin, trimethoprim-sulphamethoxazole, tetracycline, and chloramphenicol; while 75% and 100% of E. coli isolates were sensitive to cefoxitin, and ciprofloxacin respectively. Asymptomatic bacteriuria in pregnant women was prevalent in the study locality. E. coli was the common isolated urinary pathogen among urine samples of study subjects, and was found to be resistant to multiple antimicrobial agents. We suggest cefoxitin should be the drug used to treat significant bacteriuria in pregnant women in the study locality.

Antibiotic resistance phenotypes and virulence-associated genes in Escherichia coli isolated from animals and animal food products in Tunisia.

PubMed

Badi, Souhir; Cremonesi, Paola; Abbassi, Mohamed Salah; Ibrahim, Chourouk; Snoussi, Majdi; Bignoli, Giulia; Luini, Mario; Castiglioni, Bianca; Hassen, Abdennaceur

2018-05-01

Livestock and food products of animal origin constitute important reservoirs of intestinal and extraintestinal pathogenic Escherichia coli including antibiotic-resistant E. coli isolates. To assess potential risks to public health related to E. coli strains of animal origin in Tunisia, 65 E. coli isolates recovered from healthy animals and food products of animal origin were studied. Antimicrobial susceptibility was determined according to CLSI guidelines and genes encoding antibiotic resistance as well as virulence factors were investigated by PCR. High rates of antibiotic resistance were observed to kanamycin (78.4%), gentamicin (75.3%) and streptomycin (75.3%, encoded by strA-strB (7 isolates)), amoxicillin (64.6%), amoxicillin/clavulanic acid (60%), tetracycline (44.6%; tetA (8 isolates) and tetB (7 isolates)), nalidixic acid (27.6%, qnrS (3 isolates), qnrB (2 isolates) and qnrA (one isolate)) and sulfonamides (36.9%; sul1 (1 isolate), sul2 (4 isolates), and sul3 (1 isolate)). Virulotypes classified some isolates as STEC (3%), MNEC (1.5%) and atypical EPEC (1.5%). This study demonstrated high rates of antimicrobial resistance and the presence of some pathogenic pathovars from animal origins that are a cause of concern for public health.

Emergence of colistin-resistant Escherichia coli clinical isolates harboring mcr-1 in Vietnam.

PubMed

Tada, Tatsuya; Nhung, Pham Hong; Shimada, Kayo; Tsuchiya, Mitsuhiro; Phuong, Doan Mai; Anh, Nguyen Quoc; Ohmagari, Norio; Kirikae, Teruo

2017-10-01

The mcr-1 was first detected on a plasmid in colistin-resistant Escherichia coli from livestock and patients in China. We described here the emergence of colistin-resistant E. coli clinical isolates harboring mcr-1 on the chromosomes in Vietnam. To our knowledge, this is the first report of hospital-acquired E. coli isolates harboring mcr-1 in a medical setting in Vietnam. Copyright © 2017. Published by Elsevier Ltd.

Particular Biochemical Profiles for Enterohemorrhagic Escherichia coli O157:H7 Isolates on the ID 32E System

PubMed Central

Leclercq, Alexandre; Lambert, Bernard; Pierard, Denis; Mahillon, Jacques

2001-01-01

The ability of the ID 32E system to identify and discriminate 74 Escherichia coli O157 isolates among 106 E. coli non-O157 isolates was evaluated. The results showed atypical biochemical reactions but accurate identification at the species level and no unique biochemical profile numbers for E. coli O157, although these numbers were distinct from those of other serotypes. PMID:11230449

Detection, Isolation, and Molecular Subtyping of Escherichia coli O157:H7 and Campylobacter jejuni Associated with a Large Waterborne Outbreak

PubMed Central

Bopp, Dianna J.; Sauders, Brian D.; Waring, Alfred L.; Ackelsberg, Joel; Dumas, Nellie; Braun-Howland, Ellen; Dziewulski, David; Wallace, Barbara J.; Kelly, Molly; Halse, Tanya; Musser, Kimberlee Aruda; Smith, Perry F.; Morse, Dale L.; Limberger, Ronald J.

2003-01-01

The largest reported outbreak of waterborne Escherichia coli O157:H7 in the United States occurred in upstate New York following a county fair in August 1999. Culture methods were used to isolate E. coli O157:H7 from specimens from 128 of 775 patients with suspected infections. Campylobacter jejuni was also isolated from stools of 44 persons who developed diarrheal illness after attending this fair. There was one case of a confirmed coinfection with E. coli O157:H7 and C. jejuni. Molecular detection of stx1 and stx2 Shiga toxin genes, immunomagnetic separation (IMS), and selective culture enrichment were utilized to detect and isolate E. coli O157:H7 from an unchlorinated well and its distribution points, a dry well, and a nearby septic tank. PCR for stx1 and stx2 was shown to provide a useful screen for toxin-producing E. coli O157:H7, and IMS subculture improved recovery. Pulsed-field gel electrophoresis (PFGE) was used to compare patient and environmental E. coli O157:H7 isolates. Among patient isolates, 117 of 128 (91.5%) were type 1 or 1a (three or fewer bands different). Among the water distribution system isolates, 13 of 19 (68%) were type 1 or 1a. Additionally, PFGE of C. jejuni isolates revealed that 29 of 35 (83%) had indistinguishable PFGE patterns. The PFGE results implicated the water distribution system as the main source of the E. coli O157:H7 outbreak. This investigation demonstrates the potential for outbreaks involving more than one pathogen and the importance of analyzing isolates from multiple patients and environmental samples to develop a better understanding of bacterial transmission during an outbreak. PMID:12517844

Molecular Characterization of Multidrug Resistant Uropathogenic E. Coli Isolates from Jordanian Patients.

PubMed

Nairoukh, Yacoub R; Mahafzah, Azmi M; Irshaid, Amal; Shehabi, Asem A

2018-01-01

Emergence of multi-drug resistant uropathogenic E. coli strains is an increasing problem to empirical treatment of urinary tract infections in many countries. This study investigated the magnitude of this problem in Jordan. A total of 262 E. coli isolates were recovered from urine samples of Jordanian patients which were suspected to have urinary tract infections (UTIs). All isolates were primarily identified by routine biochemical tests and tested for antimicrobial susceptibility by disc diffusion method. Fifty representative Multidrug Resistance (MDR) E. coli isolates to 3 or more antibiotic classes were tested for the presence of resistance genes of blaCTX-M- 1, 9 and 15, carbapenemase ( blaIMP, blaVIM, blaNDM-1, blaOXA-48 ), fluoroquinolones mutated genes ( parC and gyrA ) and clone of ST131 type using PCR methods. A total of 150/262 (57.3%) of E. coli isolates were MDR. Urine samples of hospitalized patients showed significantly more MDR isolates than outpatients. Fifty representative MDR E. coli isolates indicated the following molecular characteristics: All were positive for mutated parC gene and gyrA and for ST131 clone, and 78% were positive for genes of CTX-M-15 , 76% for CTX-M-I and for 8% CTX-M-9 , respectively. Additionally, all 50 MDR E. coli isolates were negative for carbapenemase genes ( blaIMP, blaVIM, blaNDM-1, blaOXA-48 ), except of one isolate was positive for blaKPC-2 . This study indicates alarming high rates recovery of MDR uropathogenic E. coli from Jordanian patients associated with high rates of positive ST131 clone, fluoroquinolone resistant and important types of blaCTX-M.

Alignment-free design of highly discriminatory diagnostic primer sets for Escherichia coli O104:H4 outbreak strains.

PubMed

Pritchard, Leighton; Holden, Nicola J; Bielaszewska, Martina; Karch, Helge; Toth, Ian K

2012-01-01

An Escherichia coli O104:H4 outbreak in Germany in summer 2011 caused 53 deaths, over 4000 individual infections across Europe, and considerable economic, social and political impact. This outbreak was the first in a position to exploit rapid, benchtop high-throughput sequencing (HTS) technologies and crowdsourced data analysis early in its investigation, establishing a new paradigm for rapid response to disease threats. We describe a novel strategy for design of diagnostic PCR primers that exploited this rapid draft bacterial genome sequencing to distinguish between E. coli O104:H4 outbreak isolates and other pathogenic E. coli isolates, including the historical hæmolytic uræmic syndrome (HUSEC) E. coli HUSEC041 O104:H4 strain, which possesses the same serotype as the outbreak isolates. Primers were designed using a novel alignment-free strategy against eleven draft whole genome assemblies of E. coli O104:H4 German outbreak isolates from the E. coli O104:H4 Genome Analysis Crowd-Sourcing Consortium website, and a negative sequence set containing 69 E. coli chromosome and plasmid sequences from public databases. Validation in vitro against 21 'positive' E. coli O104:H4 outbreak and 32 'negative' non-outbreak EHEC isolates indicated that individual primer sets exhibited 100% sensitivity for outbreak isolates, with false positive rates of between 9% and 22%. A minimal combination of two primers discriminated between outbreak and non-outbreak E. coli isolates with 100% sensitivity and 100% specificity. Draft genomes of isolates of disease outbreak bacteria enable high throughput primer design and enhanced diagnostic performance in comparison to traditional molecular assays. Future outbreak investigations will be able to harness HTS rapidly to generate draft genome sequences and diagnostic primer sets, greatly facilitating epidemiology and clinical diagnostics. We expect that high throughput primer design strategies will enable faster, more precise responses to future disease outbreaks of bacterial origin, and help to mitigate their societal impact.

Determination of gyrA and parC mutations and prevalence of plasmid-mediated quinolone resistance genes in Escherichia coli and Klebsiella pneumoniae isolated from patients with urinary tract infection in Iran.

PubMed

Mirzaii, Mehdi; Jamshidi, Sanaz; Zamanzadeh, Maryam; Marashifard, Masoud; Malek Hosseini, Seyed Ali Asghar; Haeili, Mehri; Jahanbin, Fariba; Mansouri, Fariba; Darban-Sarokhalil, Davood; Khoramrooz, Seyed Sajjad

2018-06-01

Fluoroquinolones (FQs) are recommended as the drugs of choice for the empirical treatment of urinary tract infections (UTIs). This study investigated the molecular determinants of FQ resistance in Escherichia coli and Klebsiella pneumoniae isolates in Iran. A total of 364 clinical isolates of E. coli (n=144) and K. pneumoniae (n=220) were collected from patients with UTI. Susceptibility of the isolates to ciprofloxacin, levofloxacin, gatifloxacin and nalidixic acid was evaluated by disk diffusion. The presence of qnrA, qnrB and qnrS genes was assessed by PCR. Nucleotide sequences of the gyrA and parC genes were determined. Eighty-seven (60.4%) and 15 (6.8%) E. coli and K. pneumoniae isolates, respectively, were resistant to at least one of the tested FQs. Plasmid-mediated quinolone resistance (PMQR) genes were detected in 12.6% and 60.0% of FQ-resistant E. coli and K. pneumoniae, respectively. Whilst qnrB predominated in K. pneumoniae, qnrS was the most prevalent PMQR gene in E. coli. S83L (98.9%) and D87N (59.8%) were the most frequent mutations identified in GyrA of E. coli, and 55.2% (n=48) of FQ-resistant E. coli isolates had mutation in ParC harbouring S80I and E84V substitutions. The GyrAS83L substitution was found in only one FQ-resistant K. pneumoniae isolate. FQ resistance was much more common in E. coli isolates than in K. pneumoniae. Whilst mutations in the drug target-encoding genes gyrA and parC were the major mechanisms involved in FQ resistance in E. coli, PMQR determinants commonly mediated FQ resistance in K. pneumoniae. Copyright © 2018. Published by Elsevier Ltd.

Fluoroquinolone-resistant and extended-spectrum β-lactamase-producing Escherichia coli from the milk of cows with clinical mastitis in Southern Taiwan.

PubMed

Su, Yaochi; Yu, Chang-You; Tsai, Yilin; Wang, Shao-Hung; Lee, Chihan; Chu, Chishih

2016-12-01

Escherichia coli is a common pathogen to cause clinical and subclinical mastitis in cows. A total of 57 E. coli isolates from raw milk from cows were characterized genetically and biochemically. Extended-spectrum β-lactamase (ESBL) genes, the mechanism for fluoroquinolone resistance, and variations in virulence genes and genomes of these E. coli isolates were investigated by the antimicrobial susceptibility test, simplex and multiplex polymerase chain reaction (PCR), and pulsed-field gel electrophoresis (PFGE). All E. coli isolates were resistant to cloxacillin (100%) and to a lesser extent (50%) to tetracycline, neomycin, gentamycin, ampicillin, ceftriaxone, cefotaxime (CTX), and ceftazidime (CAZ). Nearly 70% of the isolates were resistant to at least two antimicrobials and 28.1% carried AmpA and AmpC genes simultaneously. The predominant bla gene was bla TEM , followed by bla CMY , bla CTX , bla SHV , and bla DHA. Among the six (10.5%) ESBL-producing E. coli carrying bla CTX-M15 , bla CTX-M55 , or bla CTX-M14 , two isolates 31 of ST410 in the ST23 complex and 58 of ST167 in the ST10 complex were also resistant to ciprofloxacin, enrofloxacin, and levofloxacin, with mutations at codon 83 from serine to leucine and codon 87 from aspartic acid to asparagine in GyrA and at codon 80 from serine to isoleucine in ParC. These isolates were genetically diverse in pulsotype analysis, lacked toxin genes of human pathogenic E. coli and carried mostly the prevalent virulence genes fimH, papGII, and α-hemolysin. Lacking virulence genes examined, genetic diverse E. coli isolates are unrelated to human pathogenic E. coli. Enhancing sanitation in milk processing and transportation is needed to eliminate multidrug-resistant (MDR), fluoroquinolone-resistant, and ESBL-producing E. coli isolates. Copyright © 2014. Published by Elsevier B.V.

The Escherichia coli argW-dsdCXA genetic island is highly variable, and E. coli K1 strains commonly possess two copies of dsdCXA.

PubMed

Moritz, Rebecca L; Welch, Rodney A

2006-11-01

The genome sequences of Escherichia coli pathotypes reveal extensive genetic variability in the argW-dsdCXA island. Interestingly, the archetype E. coli K1 neonatal meningitis strain, strain RS218, has two copies of the dsdCXA genes for d-serine utilization at the argW and leuX islands. Because the human brain contains d-serine, an epidemiological study emphasizing K1 isolates surveyed the dsdCXA copy number and function. Forty of 41 (97.5%) independent E. coli K1 isolates could utilize d-serine. Southern blot hybridization revealed physical variability within the argW-dsdC region, even among 22 E. coli O18:K1:H7 isolates. In addition, 30 of 41 K1 strains, including 21 of 22 O18:K1:H7 isolates, had two dsdCXA loci. Mutational analysis indicated that each of the dsdA genes is functional in a rifampin-resistant mutant of RS218, mutant E44. The high percentage of K1 strains that can use d-serine is in striking contrast to our previous observation that only 4 of 74 (5%) isolates in the diarrheagenic E. coli (DEC) collection have this activity. The genome sequence of diarrheagenic E. coli isolates indicates that the csrRAKB genes for sucrose utilization are often substituted for dsdC and a portion of dsdX present at the argW-dsdCXA island of extraintestinal isolates. Among DEC isolates there is a reciprocal pattern of sucrose fermentation versus d-serine utilization. The ability to use d-serine is a trait strongly selected for among E. coli K1 strains, which have the ability to infect a wide range of extraintestinal sites. Conversely, diarrheagenic E. coli pathotypes appear to have substituted sucrose for d-serine as a potential nutrient.

Anti-Escherichia coli activity of extracts from Schinus terebinthifolius fruits and leaves.

PubMed

da Silva, Jessica H S; Simas, Naomi K; Alviano, Celuta S; Alviano, Daniela S; Ventura, José A; de Lima, Eliandro J; Seabra, Sergio H; Kuster, Ricardo M

2018-06-01

Ethanol extracts obtained from Schinus terebinthifolius Raddi fruits and leaves were active against Escherichia coli with MIC of 78 μg mL -1 for both extracts. Phytochemical analyses revealed a major presence of phenolic acids, tannins, fatty acids and acid triterpenes in the leaves and phenolic acids, fatty acids, acid triterpenes and biflavonoids in the fruits. Major compounds isolated from the plant, such as the acid triterpene schinol, the phenolic acid derivative ethyl gallate and the biflavonoids agathisflavone and tetrahydroamentoflavone, showed very little activity against E. coli. Bioautography of the ethanol extracts on silica gel plate showed inhibition zones for E. coli. They were removed from the plate and the compounds identified as a mixture of myristic, pentadecanoic, palmitic, heptadecanoic, stearic, nonadecanoic, eicosanoic, heneicosanoic and behenic fatty acids.

Uropathogenic Escherichia coli are less likely than paired fecal E. coli to have CRISPR loci.

PubMed

Dang, Trang Nguyen Doan; Zhang, Lixin; Zöllner, Sebastian; Srinivasan, Usha; Abbas, Khadija; Marrs, Carl F; Foxman, Betsy

2013-10-01

CRISPRs (Clustered Regularly Interspaced Short Palindromic Repeats) are short fragments of DNA that act as an adaptive immune system protecting bacteria against invasion by phages, plasmids or other forms of foreign DNA. Bacteria without a CRISPR locus may more readily adapt to environmental changes by acquiring foreign genetic material. Uropathogenic Escherichia coli (UPEC) live in a number of environments suggesting an ability to rapidly adapt to new environments. If UPEC are more adaptive than commensal E. coli we would expect that UPEC would have fewer CRISPR loci, and--if loci are present--that they would harbor fewer spacers than CRISPR loci in fecal E. coli. We tested this in vivo by comparing the number of CRISPR loci and spacers, and sensitivity to antibiotics (resistance is often obtained via plasmids) among 81 pairs of UPEC and fecal E. coli isolated from women with urinary tract infection. Each pair included one uropathogen and one commensal (fecal) sample from the same female patient. Fecal isolates had more repeats (p=0.009) and more unique spacers (p<0.0001) at four CRISPR loci than uropathogens. By contrast, uropathogens were more likely than fecal E. coli to be resistant to ampicillin, cefazolin and trimethoprim/sulfamethoxazole. However, no consistent association between CRISPRs and antibiotic resistance was identified. To our knowledge, this is the first study to compare fecal E. coli and pathogenic E. coli from the same individuals, and to test the association of CRISPR loci with antibiotic resistance. Our results suggest that the absence of CRISPR loci may make UPEC more susceptible to infection by phages or plasmids and allow them to adapt more quickly to various environments. Copyright © 2013 Elsevier B.V. All rights reserved.

Antimicrobial Resistance of Escherichia coli, Enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus from Raw Fish and Seafood Imported into Switzerland.

PubMed

Boss, Renate; Overesch, Gudrun; Baumgartner, Andreas

2016-07-01

A total of 44 samples of salmon, pangasius (shark catfish), shrimps, and oysters were tested for the presence of Escherichia coli, enterococci, Pseudomonas aeruginosa, and Staphylococcus aureus, which are indicator organisms commonly used in programs to monitor antibiotic resistance. The isolated bacterial strains, confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectroscopy, were tested against a panel of 29 antimicrobial agents to obtain MICs. Across the four sample types, Enterococcus faecalis (59%) was most common, followed by E. coli (55%), P. aeruginosa (27%), and S. aureus (9%). All bacterial species were resistant to some antibiotics. The highest rates of resistance were in E. faecalis to tetracycline (16%), in E. coli to ciprofloxacin (22%), and in S. aureus to penicillin (56%). Antibiotic resistance was found among all sample types, but salmon and oysters were less burdened than were shrimps and pangasius. Multidrug-resistant (MDR) strains were exclusively found in shrimps and pangasius: 17% of pangasius samples (MDR E. coli and S. aureus) and 64% of shrimps (MDR E. coli, E. faecalis, and S. aureus). Two of these MDR E. coli isolates from shrimps (one from an organic sample) were resistant to seven antimicrobial agents. Based on these findings, E. coli in pangasius, shrimps, and oysters, E. faecalis in pangasius, shrimps, and salmon, and P. aeruginosa in pangasius and shrimps are potential candidates for programs monitoring antimicrobial resistance. Enrichment methods for the detection of MDR bacteria of special public health concern, such as methicillin-resistant S. aureus and E. coli producing extended-spectrum β-lactamases and carbapenemases, should be implemented.

The population structure of Escherichia coli isolated from subtropical and temperate soils.

PubMed

Byappanahalli, Muruleedhara N; Yan, Tao; Hamilton, Matthew J; Ishii, Satoshi; Fujioka, Roger S; Whitman, Richard L; Sadowsky, Michael J

2012-02-15

While genotypically-distinct naturalized Escherichia coli strains have been shown to occur in riparian soils of Lake Michigan and Lake Superior watersheds, comparative analyses of E. coli populations in diverse soils across a range of geographic and climatic conditions have not been investigated. The main objectives of this study were to: (a) examine the population structure and genetic relatedness of E. coli isolates collected from different soil types on a tropical island (Hawaii), and (b) determine if E. coli populations from Hawaii and temperate soils (Indiana, Minnesota) shared similar genotypes that may be reflective of biome-related soil conditions. DNA fingerprint and multivariate statistical analyses were used to examine the population structure and genotypic characteristics of the E. coli isolates. About 33% (98 of 293) of the E. coli from different soil types and locations on the island of Oahu, Hawaii, had unique DNA fingerprints, indicating that these bacteria were relatively diverse; the Shannon diversity index for the population was 4.03. Nearly 60% (171 of 293) of the E. coli isolates from Hawaii clustered into two major groups and the rest, with two or more isolates, fell into one of 22 smaller groups, or individual lineages. Multivariate analysis of variance of 89, 21, and 106 unique E. coli DNA fingerprints for Hawaii, Indiana, and Minnesota soils, respectively, showed that isolates formed tight cohesive groups, clustering mainly by location. However, there were several instances of clonal isolates being shared between geographically different locations. Thus, while nearly identical E. coli strains were shared between disparate climatologically- and geographically-distinct locations, a vast majority of the soil E. coli strains were genotypically diverse and were likely derived from separate lineages. This supports the hypothesis that these bacteria are not unique and multiple genotypes can readily adapt to become part of the soil autochthonous microflora. Copyright © 2012 Elsevier B.V. All rights reserved.

The population structure of Escherichia coli isolated from subtropical and temperate soils

USGS Publications Warehouse

Byappanahalli, Muruleedhara N.; Yan, Tao; Hamilton, Matthew J.; Ishii, Satoshi; Fujioka, Roger S.; Whitman, Richard L.; Sadowsky, Michael J.

2012-01-01

While genotypically-distinct naturalized Escherichia coli strains have been shown to occur in riparian soils of Lake Michigan and Lake Superior watersheds, comparative analyses of E. coli populations in diverse soils across a range of geographic and climatic conditions have not been investigated. The main objectives of this study were to: (a) examine the population structure and genetic relatedness of E. coli isolates collected from different soil types on a tropical island (Hawaii), and (b) determine if E. coli populations from Hawaii and temperate soils (Indiana, Minnesota) shared similar genotypes that may be reflective of biome-related soil conditions. DNA fingerprint and multivariate statistical analyses were used to examine the population structure and genotypic characteristics of the E. coli isolates. About 33% (98 of 293) of the E. coli from different soil types and locations on the island of Oahu, Hawaii, had unique DNA fingerprints, indicating that these bacteria were relatively diverse; the Shannon diversity index for the population was 4.03. Nearly 60% (171 of 293) of the E. coli isolates from Hawaii clustered into two major groups and the rest, with two or more isolates, fell into one of 22 smaller groups, or individual lineages. Multivariate analysis of variance of 89, 21, and 106 unique E. coli DNA fingerprints for Hawaii, Indiana, and Minnesota soils, respectively, showed that isolates formed tight cohesive groups, clustering mainly by location. However, there were several instances of clonal isolates being shared between geographically different locations. Thus, while nearly identical E. coli strains were shared between disparate climatologically- and geographically-distinct locations, a vast majority of the soil E. coli strains were genotypically diverse and were likely derived from separate lineages. This supports the hypothesis that these bacteria are not unique and multiple genotypes can readily adapt to become part of the soil autochthonous microflora.

Isolation and Characteristics of Shiga Toxin 2f-Producing Escherichia coli among Pigeons in Kyushu, Japan

PubMed Central

Murakami, Koichi; Etoh, Yoshiki; Ichihara, Sachiko; Maeda, Eriko; Takenaka, Shigeyuki; Horikawa, Kazumi; Narimatsu, Hiroshi; Kawano, Kimiko; Kawamura, Yoshiaki; Ito, Kenitiro

2014-01-01

An increasing number of Shiga toxin 2f-producing Escherichia coli (STEC2f) infections in humans are being reported in Europe, and pigeons have been suggested as a reservoir for the pathogen. In Japan, there is very little information regarding carriage of STEC2f by pigeons, prompting the need for further investigation. We collected 549 samples of pigeon droppings from 14 locations in Kyushu, Japan, to isolate STEC2f and to investigate characteristics of the isolates. Shiga toxin stx 2f gene fragments were detected by PCR in 16 (2.9%) of the 549 dropping samples across four of the 14 locations. We obtained 23 STEC2f-isolates from seven of the original samples and from three pigeon dropping samples collected in an additional sampling experiment (from a total of seven locations across both sampling periods). Genotypic and phenotypic characteristics were then examined for selected isolates from each of 10 samples with pulsed-field gel electrophoresis profiles. Eight of the stx 2f gene fragments sequenced in this study were homologous to others that were identified in Europe. Some isolates also contained virulence-related genes, including lpfA O26, irp 2, and fyuA, and all of the 10 selected isolates maintained the eae, astA, and cdt genes. Moreover, five of the 10 selected isolates contained sfpA, a gene that is restricted to Shiga toxin-producing E. coli O165:H2 and sorbitol-fermenting Shiga toxin-producing E. coli O157:NM. We document serotypes O152:HNM, O128:HNM, and O145:H34 as STEC2f, which agrees with previous studies on pigeons and humans. Interestingly, O119:H21 was newly described as STEC2f. O145:H34, with sequence type 722, was described in a German study in humans and was also isolated in the current study. These results revealed that Japanese zoonotic STEC2f strains harboring several virulence-related factors may be of the same clonal complexes as some European strains. These findings provide useful information for public health-related disease management strategies in Japan. PMID:24465879

Altered Escherichia coli membrane protein assembly machinery allows proper membrane assembly of eukaryotic protein vitamin K epoxide reductase.

PubMed

Hatahet, Feras; Blazyk, Jessica L; Martineau, Eugenie; Mandela, Eric; Zhao, Yongxin; Campbell, Robert E; Beckwith, Jonathan; Boyd, Dana

2015-12-08

Functional overexpression of polytopic membrane proteins, particularly when in a foreign host, is often a challenging task. Factors that negatively affect such processes are poorly understood. Using the mammalian membrane protein vitamin K epoxide reductase (VKORc1) as a reporter, we describe a genetic selection approach allowing the isolation of Escherichia coli mutants capable of functionally expressing this blood-coagulation enzyme. The isolated mutants map to components of membrane protein assembly and quality control proteins YidC and HslV. We show that changes in the VKORc1 sequence and in the YidC hydrophilic groove along with the inactivation of HslV promote VKORc1 activity and dramatically increase its expression level. We hypothesize that such changes correct for mismatches in the membrane topogenic signals between E. coli and eukaryotic cells guiding proper membrane integration. Furthermore, the obtained mutants allow the study of VKORc1 reaction mechanisms, inhibition by warfarin, and the high-throughput screening for potential anticoagulants.

Altered Escherichia coli membrane protein assembly machinery allows proper membrane assembly of eukaryotic protein vitamin K epoxide reductase

PubMed Central

Hatahet, Feras; Blazyk, Jessica L.; Martineau, Eugenie; Mandela, Eric; Zhao, Yongxin; Campbell, Robert E.; Beckwith, Jonathan; Boyd, Dana

2015-01-01

Functional overexpression of polytopic membrane proteins, particularly when in a foreign host, is often a challenging task. Factors that negatively affect such processes are poorly understood. Using the mammalian membrane protein vitamin K epoxide reductase (VKORc1) as a reporter, we describe a genetic selection approach allowing the isolation of Escherichia coli mutants capable of functionally expressing this blood-coagulation enzyme. The isolated mutants map to components of membrane protein assembly and quality control proteins YidC and HslV. We show that changes in the VKORc1 sequence and in the YidC hydrophilic groove along with the inactivation of HslV promote VKORc1 activity and dramatically increase its expression level. We hypothesize that such changes correct for mismatches in the membrane topogenic signals between E. coli and eukaryotic cells guiding proper membrane integration. Furthermore, the obtained mutants allow the study of VKORc1 reaction mechanisms, inhibition by warfarin, and the high-throughput screening for potential anticoagulants. PMID:26598701

Escherichia coli Sequence Type 131 H30 Is the Main Driver of Emerging Extended-Spectrum-β-Lactamase-Producing E. coli at a Tertiary Care Center.

PubMed

Johnson, James R; Johnston, Brian; Thuras, Paul; Launer, Bryn; Sokurenko, Evgeni V; Miller, Loren G

2016-01-01

The H 30 strain of Escherichia coli sequence type 131 (ST131- H 30) is a recently emerged, globally disseminated lineage associated with fluoroquinolone resistance and, via its H 30Rx subclone, the CTX-M-15 extended-spectrum beta-lactamase (ESBL). Here, we studied the clonal background and resistance characteristics of 109 consecutive recent E. coli clinical isolates (2015) and 41 historical ESBL-producing E. coli blood isolates (2004 to 2011) from a public tertiary care center in California with a rising prevalence of ESBL-producing E. coli isolates. Among the 2015 isolates, ST131, which was represented mainly by ST131- H 30, was the most common clonal lineage (23% overall). ST131- H 30 accounted for 47% (8/17) of ESBL-producing, 47% (14/30) of fluoroquinolone-resistant, and 33% (11/33) of multidrug-resistant isolates. ST131- H 30 also accounted for 53% (8/14) of dually fluoroquinolone-resistant, ESBL-producing isolates, with the remaining 47% comprised of diverse clonal groups that contributed a single isolate each. ST131- H 30Rx, with CTX-M-15, was the major ESBL producer (6/8) among ST131- H 30 isolates. ST131- H 30 and H 30Rx also dominated (46% and 37%, respectively) among the historical ESBL-producing isolates (2004 to 2011), without significant temporal shifts in relative prevalence. Thus, this medical center's recently emerging ESBL-producing E. coli strains, although multiclonal, are dominated by ST131- H 30 and H 30Rx, which are the only clonally expanded fluoroquinolone-resistant, ESBL-producing lineages. Measures to rapidly and effectively detect, treat, and control these highly successful lineages are needed. IMPORTANCE The ever-rising prevalence of resistance to first-line antibiotics among clinical Escherichia coli isolates leads to worse clinical outcomes and higher health care costs, thereby creating a need to discover its basis so that effective interventions can be developed. We found that the H 30 subset within E. coli sequence type 131 (ST131- H 30) is currently, and has been since at least 2004, the main E. coli lineage contributing to key resistance phenotypes-including extended-spectrum-beta-lactamase (ESBL) production, fluoroquinolone resistance, multidrug resistance, and dual ESBL production-plus-fluoroquinolone resistance-at a United States tertiary care center with a rising prevalence of ESBL-producing E. coli isolates. This identifies ST131- H 30 as a target for diagnostic tests and preventive measures designed to curb the emergence of multidrug-resistant E. coli isolates and/or to blunt its clinical impact.

An outbreak of Vero cytotoxin producing Escherichia coli O157 infection associated with takeaway sandwiches.

PubMed

McDonnell, R J; Rampling, A; Crook, S; Cockcroft, P M; Wilshaw, G A; Cheasty, T; Stuart, J

1997-12-12

An outbreak of food poisoning due to Escherichia coli O157 phage type 2 Vero cytotoxin 2 affected 26 people in southern counties of England in May and June 1995. The organism was isolated from faecal specimens from 23 patients, 16 of whom lived in Dorset and seven in Hampshire. Isolates were indistinguishable by phage typing, Vero cytotoxin gene typing, restriction fragment length polymorphism, and pulsed field gel electrophoresis. Three associated cases, linked epidemiologically to the outbreak, were confirmed serologically by detection of antibodies to E. coli O157 lipopolysaccharide. Twenty-two of the 26 patients were adults: four were admitted to hospital with haemorrhagic colitis. Four cases were children: two were admitted to hospital with haemolytic uraemic syndrome (HUS). There were no deaths. Although E. coli O157 was not isolated from any food samples, illness was associated with having eaten cold meats in sandwiches bought from two sandwich producers, in Weymouth and in Portsmouth. Both shops were supplied by the same wholesaler, who kept no records and obtained cooked meats from several sources in packs that did not carry adequate identification marks. It was, therefore, impossible to trace back to the original producer or to investigate further to determine the origin of contamination with E. coli O157. To protect the public health it is essential that all wholesale packs of ready-to-eat food carry date codes and the producer's identification mark. Detailed record keeping should be part of hazard analysis critical control point (HACCP) systems and should be maintained throughout the chain of distribution from the producer to retail outlets.

Distribution of Diverse Escherichia coli between Cattle and Pasture.

PubMed

NandaKafle, Gitanjali; Seale, Tarren; Flint, Toby; Nepal, Madhav; Venter, Stephanus N; Brözel, Volker S

2017-09-27

Escherichia coli is widely considered to not survive for extended periods outside the intestines of warm-blooded animals; however, recent studies demonstrated that E. coli strains maintain populations in soil and water without any known fecal contamination. The objective of this study was to investigate whether the niche partitioning of E. coli occurs between cattle and their pasture. We attempted to clarify whether E. coli from bovine feces differs phenotypically and genotypically from isolates maintaining a population in pasture soil over winter. Soil, bovine fecal, and run-off samples were collected before and after the introduction of cattle to the pasture. Isolates (363) were genotyped by uidA and mutS sequences and phylogrouping, and evaluated for curli formation (Rough, Dry, And Red, or RDAR). Three types of clusters emerged, viz. bovine-associated, clusters devoid of cattle isolates and representing isolates endemic to the pasture environment, and clusters with both. All isolates clustered with strains of E. coli sensu stricto, distinct from the cryptic species Clades I, III, IV, and V. Pasture soil endemic and bovine fecal populations had very different phylogroup distributions, indicating niche partitioning. The soil endemic population was largely comprised of phylogroup B1 and had a higher average RDAR score than other isolates. These results indicate the existence of environmental E. coli strains that are phylogenetically distinct from bovine fecal isolates, and that have the ability to maintain populations in the soil environment.

Genotypic and phenotypic characterization of invasive neonatal Escherichia coli clinical isolates.

PubMed

Shakir, Salika Mehreen; Goldbeck, Jessica Marie; Robison, Denise; Eckerd, Annette Marie; Chavez-Bueno, Susana

2014-11-01

The objective of this study was to describe the clinical characteristics of neonates with Escherichia coli bacteremia and the antibiotic resistance pattern of the bacterial isolates. We assessed the isolates' genetic relatedness and virulence phenotypic characteristics in vitro. A total of 24 neonates with E. coli bacteremia were identified prospectively in a tertiary-care hospital. Clinical and antibiotic resistance data were investigated. The E. coli isolates were analyzed by multilocus sequence typing (MLST); the presence of the K1 capsule and their ability to invade intestinal epithelial cells were also assessed. Most newborns were very low birth weight infants. Overall, 75% of the isolates were ampicillin resistant and 17% were gentamicin and tobramycin nonsusceptible. MLST determined sequence types 95 and 131 (ST95 and ST131) predominated, with ST131 becoming significantly more prevalent recently. The K1 capsule was present in 50% of the isolates. ST131 isolates and those producing bacteremia in newborns younger than 7 days showed a highly invasive phenotype. Resistance to antibiotics currently used empirically to treat newborns is present in bacteremia-producing E. coli. Clonal spread among newborns of multidrug-resistant E. coli is possible; therefore, continued surveillance is needed. Identification of additional virulence factors associated with increased invasion in neonatal E. coli strains is important and further studies are warranted. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Study on E. coli and Salmonella biofilms from fresh fruits and vegetables.

PubMed

Amrutha, Balagopal; Sundar, Kothandapani; Shetty, Prathapkumar Halady

2017-04-01

Foodborne outbreaks associated with fresh fruits and vegetables are on the rise worldwide. Biofilm formation is one of the important traits of pathogens making them strongly attached to substrates as well as express virulence phenotypes. Present study investigates the biofilm forming ability of E. coli and Salmonella sp. isolated from fresh fruits and vegetables. A total of 53 strains, including 35 E. coli and 18 Salmonella sp. isolated from different fruit and vegetable samples were taken into account for the study. Initial screening for biofilm formation was done using Congo Red agar plate test. Results revealed that 22.8% E. coli and 22.2% Salmonella sp. were potential biofilm formers. However, the MTP (Micro-Titre Plate) assay suggested more isolates of both E. coli and Salmonella sp. were moderate to strong biofilm producers. Agar plate diffusion assay with Agrobacterium tumefaciens NTL-4 showed the production of quorum signaling molecules (AHLs) by three isolates of E. coli and one Salmonella sp. Two E. coli isolates showed a significant amount of EPS production indicating higher biofilm forming potential. The Presence of LUX R homologue gene ( sdi A) in two of the Salmonella isolates were confirmed by PCR which demonstrated their potential pathogenicity. Results of the work underline the biofilm forming and potentially virulent capacities of isolates from the surface of fruits and vegetables.

Evaluation of a rapid tube assay for presumptive identification of Escherichia coli from veterinary specimens.

PubMed Central

Iritani, B; Inzana, T J

1988-01-01

Three hundred sixty-six isolates of gram-negative, oxidase-negative bacteria from veterinary specimens were tested by a tube test for identification as Escherichia coli by production within 60 min of indole, beta-galactosidase, and beta-glucuronidase. The test correctly identified 255 of 269 isolates of E. coli (95% sensitivity) and correctly indicated that 97 of 97 isolates were not E. coli (100% specificity). We conclude that production of indole, beta-galactosidase, and beta-glucuronidase as measured by a rapid tube test is useful for identification of E. coli from veterinary specimens. PMID:3128581

Susceptibility of Escherichia coli isolated from uteri of postpartum dairy cows to antibiotic and environmental bacteriophages. Part I: Isolation and lytic activity estimation of bacteriophages.

PubMed

Bicalho, R C; Santos, T M A; Gilbert, R O; Caixeta, L S; Teixeira, L M; Bicalho, M L S; Machado, V S

2010-01-01

The objective of this study was to isolate bacteriophages from environmental samples of 2 large commercial dairy farms using Escherichia coli isolated from the uteri of postpartum Holstein dairy cows as hosts. A total of 11 bacteriophage preparations were isolated from manure systems of commercial dairy farms and characterized for in vitro antimicrobial activity. In addition, a total of 57 E. coli uterine isolates from 5 dairy cows were phylogenetically grouped by triplex PCR. Each E. coli bacterial host from the uterus was inoculated with their respective bacteriophage preparation at several different multiplicities of infections (MOI) to determine minimum inhibitory MOI. The effect of a single dose (MOI=10(2)) of bacteriophage on the growth curve of all 57 E. coli isolates was assessed using a microplate technique. Furthermore, genetic diversity within and between the different bacteriophage preparations was assessed by bacteriophage purification followed by DNA extraction, restriction, and agarose gel electrophoresis. Phylogenetic grouping based on triplex PCR showed that all isolates of E. coli belonged to phylogroup B1. Bacterial growth was completely inhibited at considerably low MOI, and the effect of a single dose (MOI=10(2)) of bacteriophage preparations on the growth curve of all 57 E. coli isolates showed that all bacteriophage preparations significantly decreased the growth rate of the isolates. Bacteriophage preparation 1230-10 had the greatest antimicrobial activity and completely inhibited the growth of 71.7% (n=57) of the isolates. The combined action of bacteriophage preparations 1230-10, 6375-10, 2540-4, and 6547-2, each at MOI=10(2), had the broadest spectrum of action and completely inhibited the growth (final optical density at 600 nm

Free-radical scavenging activity and antibacterial impact of Greek oregano isolates obtained by SFE.

PubMed

Stamenic, Marko; Vulic, Jelena; Djilas, Sonja; Misic, Dusan; Tadic, Vanja; Petrovic, Slobodan; Zizovic, Irena

2014-12-15

The antioxidant and antibacterial properties of Greek oregano extracts obtained by fractional supercritical fluid extraction (SFE) with carbon dioxide were investigated and compared with the properties of essential oil obtained by hydrodistillation. According to DPPH, hydroxyl radical and superoxide anion radical scavenging activity assays, the supercritical extracts expressed stronger antioxidant activity comparing to the essential oil. The most effective was the supercritical extract obtained by fractional extraction at 30 MPa and 100°C after the volatile fraction had been extracted at lower pressure. At the same time this extract showed strong antibacterial activity against staphylococci, including MRSA strain, but did not affect Escherichia coli of normal intestinal flora. The essential oil obtained by hydrodistillation showed stronger antibacterial activity against E. coli, Salmonella and Klebsiella pneumoniae, comparing to the supercritical extracts but at the same affected the normal gut flora. Copyright © 2014 Elsevier Ltd. All rights reserved.

Draft genome sequences of four uropathogenic escherichia coli 04:H5 isolates (ATCC 700414,700415,700416 and 700417)

USDA-ARS?s Scientific Manuscript database

Uropathogenic Escherichia coli O4: H5 isolates ATCC 700414, 700415, 700416, and 700417 were recovered from women with first-time urinary tract infections. Here, we report the draft genome sequences for these four E. coli isolates, which are currently being used to validate food safety processing tec...

Draft Genomic Sequencing of Six Potential Extraintestinal Pathogenic Escherichia coli Isolates from Retail Chicken Meat

PubMed Central

Xu, Aixia; Johnson, James R.; Sheen, Shiowshuh; Needleman, David S.

2018-01-01

ABSTRACT Potential extraintestinal pathogenic Escherichia coli strains DP254, WH333, WH398, F356, FEX675, and FEX725 were isolated from retail chicken meat products. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used in food safety research. PMID:29798928

Empiric antibiotic treatment for urinary tract infection in preschool children: susceptibilities of urine sample isolates.

PubMed

Butler, Christopher C; O'Brien, Kathryn; Wootton, Mandy; Pickles, Timothy; Hood, Kerenza; Howe, Robin; Waldron, Cherry-Ann; Thomas-Jones, Emma; Dudley, Jan; Van Der Voort, Judith; Rumsby, Kate; Little, Paul; Downing, Harriet; Harman, Kim; Hay, Alastair D

2016-04-01

Antibiotic treatment recommendations based on susceptibility data from routinely submitted urine samples may be biased because of variation in sampling, laboratory procedures and inclusion of repeat samples, leading to uncertainty about empirical treatment. To describe and compare susceptibilities of Escherichia coli cultured from routinely submitted samples, with E. coli causing urinary tract infection (UTI) from a cohort of systematically sampled, acutely unwell children. Susceptibilities of 1458 E. coli isolates submitted during the course of routine primary care for children <5 years (routine care samples), compared to susceptibilities of 79 E. coli isolates causing UTI from 5107 children <5 years presenting to primary care with an acute illness [systematic sampling: the Diagnosis of Urinary Tract infection in Young children (DUTY) cohort]. The percentage of E. coli sensitive to antibiotics cultured from routinely submitted samples were as follows: amoxicillin 45.1% (95% confidence interval: 42.5-47.7%); co-amoxiclav using the lower systemic break point (BP) 86.6% (84.7-88.3%); cephalexin 95.1% (93.9-96.1%); trimethoprim 74.0% (71.7-76.2%) and nitrofurantoin 98.2% (97.4-98.8%). The percentage of E. coli sensitive to antibiotics cultured from systematically sampled DUTY urines considered to be positive for UTI were as follows: amoxicillin 50.6% (39.8-61.4%); co-amoxiclav using the systemic BP 83.5% (73.9-90.1%); co-amoxiclav using the urinary BP 94.9% (87.7-98.4%); cephalexin 98.7% (93.2-99.8%); trimethoprim 70.9% (60.1-80.0%); nitrofurantoin 100% (95.3-100.0%) and ciprofloxacin 96.2% (89.4-98.7%). Escherichia coli susceptibilities from routine and systematically obtained samples were similar. Most UTIs in preschool children remain susceptible to nitrofurantoin, co-amoxiclav and cephalexin. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Colonization, resistance to bile, and virulence properties of Escherichia coli strains: Unusual characteristics associated with biliary tract diseases.

PubMed

Razaghi, Maryam; Tajeddin, Elahe; Ganji, Leila; Alebouyeh, Masoud; Alizadeh, Amir Houshang Mohammad; Sadeghi, Amir; Zali, Mohammad Reza

2017-10-01

Escherichia coli is the species that is most frequently isolated from bile of patients with biliary tract diseases. This study was aimed to investigate any association between resistance and virulence properties of these isolates with occurrence of the diseases. A total of 102 bile samples were obtained from patients subjected to endoscopic retrograde cholangiopancreatography for different biliary diseases. Clinical data were collected and culture of the bile samples was done on selective media. Resistance of characterized Escherichia coli isolates to deoxycholate sodium (0-7%) and nineteen antibiotics was determined and PCR using 16 pairs of primers targeting stx1, stx2, exhA, eae, bfp, agg, pcvd432, lt, st, ipaH, pic, pet, ast, set, sen, and cdtB genes was done. Our results showed a statistically significant association between E. coli colonization and existence of common bile duct and gallbladder stones (p value 0.028). Out of the 22 E. coli strains (22/102) multidrug resistance phenotype was present in 95.45%. None of the strains belonged to common E. coli pathotypes. However, bfp + EhxA-hly, bfp + astA, bfp + EhxA-hly + pic, and EhxA-hly + pic + astA, bfp, and astA genotypes were detected in these strains. bfp (7/22, 31.8%) and astA (5/22, 22.7%) were among most frequent virulence factors in these strains. Results of this study showed significant association between colonization of E. coli and choledocholithiasis. Unusual existence of virulence gene combinations in these strains and their resistance to DOC and multiple classes of antibiotics could be considered as possible causes of their persistence in this harsh microenvironment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Emergence of antibiotic-resistant bacteria in patients with Fournier gangrene.

PubMed

Lin, Wei-Ting; Chao, Chien-Ming; Lin, Hsin-Lan; Hung, Ming-Chran; Lai, Chih-Cheng

2015-04-01

This study was conducted to investigate the bacteriology and associated patterns of antibiotic resistance Fournier gangrene. Patients with Fournier's gangrene from 2008 to 2012 were identified from the computerized database in a medical center in southern Taiwan. The medical records of all patients with Fournier's gangrene were reviewed retrospectively. There were 61 microorganisms, including 60 bacteria and one Candida spp, isolated from clinical wound specimens from 32 patients. The most common isolates obtained were Streptococcus spp. (n=12), Peptoniphilus spp. (n=8), Staphylococcus aureus (n=7), Escherichia coli (n=7), and Klebsiella pneumoniae (n=7). Among 21 strains of gram-negative bacilli, five (23.8%) were resistant to fluoroquinolones, and three isolates were resistant to ceftriaxone. Two E. coli strains produced extended-spectrum beta-lactamase. Four of the seven S. aureus isolates were methicillin-resistant. Among 15 anaerobic isolates, nine (60%) were resistant to penicillin, and eight (53.3%) were resistant to clindamycin. Four (26.7%) isolates were resistant to metronidazole. The only independent risk factor associated with mortality was inappropriate initial antibiotic treatment (p=0.021). Antibiotic-resistant bacteria are emerging in the clinical setting of Fournier gangrene. Clinicians should use broad-spectrum antibiotics initially to cover possible antibiotic-resistant bacteria.

Diversity, Frequency, and Persistence of Escherichia coli O157 Strains from Range Cattle Environments†

PubMed Central

Renter, David G.; Sargeant, Jan M.; Oberst, Richard D.; Samadpour, Mansour

2003-01-01

Genetic diversity, isolation frequency, and persistence were determined for Escherichia coli O157 strains from range cattle production environments. Over the 11-month study, analysis of 9,122 cattle fecal samples, 4,083 water source samples, and 521 wildlife fecal samples resulted in 263 isolates from 107 samples presumptively considered E. coli O157 as determined by culture and latex agglutination. Most isolates (90.1%) were confirmed to be E. coli O157 by PCR detection of intimin and Shiga toxin genes. Pulsed-field gel electrophoresis (PFGE) of XbaI-digested preparations revealed 79 unique patterns (XbaI-PFGE subtypes) from 235 typeable isolates confirmed to be E. coli O157. By analyzing up to three isolates per positive sample, we detected an average of 1.80 XbaI-PFGE subtypes per sample. Most XbaI-PFGE subtypes (54 subtypes) were identified only once, yet the seven most frequently isolated subtypes represented over one-half of the E. coli O157 isolates (124 of 235 isolates). Recurring XbaI-PFGE subtypes were recovered from samples on up to 10 sampling occasions and up to 10 months apart. Seven XbaI-PFGE subtypes were isolated from both cattle feces and water sources, and one of these also was isolated from the feces of a wild opossum (Didelphis sp.). The number of XbaI-PFGE subtypes, the variable frequency and persistence of subtypes, and the presence of identical subtypes in cattle feces, free-flowing water sources, and wildlife feces indicate that the complex molecular epidemiology of E. coli O157 previously described for confined cattle operations is also evident in extensively managed range cattle environments. PMID:12514039

Genotypic characterization of gentamicin and cephalosporin resistant Escherichia coli isolates from blood cultures in a Norwegian university hospital 2011-2015.

PubMed

Fladberg, Øyvind Andreas; Jørgensen, Silje Bakken; Aamot, Hege Vangstein

2017-01-01

Cephalosporin resistance in clinical E. coli isolates is increasing internationally. The increase has been caused by virulent and often multidrug-resistant clones, especially the extended spectrum β-lactamase (ESBL) producing E. coli clone O25b-ST131. In Norway, recommended empirical treatment of sepsis consists of gentamicin and penicillin combined, or a broad-spectrum cephalosporin. To investigate if increased gentamicin and cephalosporins resistance rates in our hospital could be caused by specific clones, we conducted a retrospective study on E. coli blood culture isolates from 2011 through 2015. All E. coli isolates non-susceptible to gentamicin and/or third-generation cephalosporins were genotyped using multiple-locus variable-number of tandem repeat analysis (MLVA) and compared with antibiotic susceptible isolates. The frequency of the most common genes causing ESBL production ( bla CTX-M , bla ampC ) was examined by Real-Time PCR. A total of 158 cephalosporin and/or gentamicin resistant and 97 control isolates were differentiated into 126 unique MLVA types. Of these, 31% of the isolates belonged to a major MLVA cluster consisting of 41% of the gentamicin resistant and 35% of the cephalosporin resistant isolates. The majority (65/80 isolates) of this MLVA cluster contained MLVA types associated with the E. coli O25b-ST131 clone. Genes encoding CTX-M enzyme phylogroups 1 and 9 occurred in 65% and 19% of cephalosporin resistant isolates, respectively, whereas bla ampC-CIT was identified in 3%. No local E. coli bacteraemia clone was identified. Antibiotic resistance was dispersed over a variety of genotypes. However, association with the international E. coli O25b-ST131 clone was frequent and may be an important driver behind increased resistance rates. Monitoring and preventing dissemination of these resistant clones are important for continued optimal treatment.

Captive and free-living urban pigeons (Columba livia) from Brazil as carriers of multidrug-resistant pathogenic Escherichia coli.

PubMed

Borges, Clarissa A; Maluta, Renato P; Beraldo, Lívia G; Cardozo, Marita V; Guastalli, Elisabete A L; Kariyawasam, Subhashinie; DebRoy, Chitrita; Ávila, Fernando A

2017-01-01

Thirty Escherichia coli isolates from captive and free-living pigeons in Brazil were characterised. Virulence-associated genes identified in pigeons included those which occur relatively frequently in avian pathogenic E. coli (APEC) from commercial poultry worldwide. Eleven of 30 E. coli isolates from pigeons, belonging mainly to B1 and B2 phylogenetic groups, had high or intermediate pathogenicity for 1-day-old chicks. The frequency of multi-drug resistant (MDR) E. coli in captive pigeons was relatively high and included one isolate positive for the extended-spectrum β-lactamase (ESBL) gene bla CTX-M-8 . Pulsed field gel electrophoresis (PFGE) showed high heterogeneity among isolates. There is potential for pigeons to transmit antibiotic resistant pathogenic E. coli to other species through environmental contamination or direct contact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evolution of the iss gene in Escherichia coli.

PubMed

Johnson, Timothy J; Wannemuehler, Yvonne M; Nolan, Lisa K

2008-04-01

The increased serum survival gene iss has long been recognized for its role in extraintestinal pathogenic Escherichia coli (ExPEC) virulence. iss has been identified as a distinguishing trait of avian ExPEC but not of human ExPEC. This gene has been localized to large virulence plasmids and shares strong similarities with the bor gene from bacteriophage lambda. Here, we demonstrate that three alleles of iss occur among E. coli isolates that appear to have evolved from a common lambda bor precursor. In addition to the occurrence of iss on the ColV/BM virulence plasmids, at least two iss alleles occur within the E. coli chromosome. One of these alleles (designated type 3) was found to occur in the genomes of all currently sequenced ExPEC strains on a similar prophage element that also harbors the Sit iron and manganese transport system. When the prevalence of the three iss types was examined among 487 E. coli isolates, the iss type 3 gene was found to occur at a high frequency among ExPEC isolates, irrespective of the host source. The plasmid-borne iss allele (designated type 1) was highly prevalent among avian pathogenic E. coli and neonatal meningitis-associated E. coli isolates but not among uropathogenic E. coli isolates. This study demonstrates the evolution of iss in E. coli and provides an additional tool for discriminating among E. coli pathotypes through the differentiation of the three iss allele types and bor.

Development of eco-friendly bioplastic like PHB by distillery effluent microorganisms.

PubMed

Gangurde, Nilesh S; Sayyed, Riyaz Z; Kiran, Shashi; Gulati, Arvind

2013-01-01

During screening for poly-β-hydroxybutyrate (PHB) producing bacteria from distillery effluent sample, six out of 30 isolates comprising of three strains of Alcaligenes sp., two strains of Bacillus sp., and one strain of Pseudomonas sp. were found to accumulate varying levels of intracellular PHB. Amongst the various isolates, Alcaligenes sp. RZS4 was found as the potent PHB-producing organism, accumulating higher amounts of PHB. PHB productivity was further enhanced in the presence of oxygen, nitrogen-limiting conditions, and cloning of PHB synthesizing genes of Alcaligenes sp. RZS 4 into Escherichia coli. A twofold increase in PHB yield was obtained from recombinant E. coli vis-à-vis Alcaligenes sp.; the recombinant E. coli accumulated more PHB in NDMM, produced good amount of PHB in a single-stage cultivation process under both nutrient-rich and nutrient-deficient conditions. Extraction of PHB with acetone-alcohol (1:1) was found as suitable method for optimum extraction of PHB as this mixture selectively extracted PHB without affecting the non-PHB cell mass. PHB extract from recombinant E. coli showed the presence of C-H, =O stretching, =C-H deformation, =C-H, =CH, and =C-O functional groups characteristic of PHB.

Clustering of antibiotic resistance of E. coli in couples: suggestion for a major role of conjugal transmission.

PubMed

Lietzau, Susanne; Raum, Elke; von Baum, Heike; Marre, Reinhard; Brenner, Hermann

2006-07-18

Spread of antibiotic resistance in hospitals is a well-known problem, but studies investigating the importance of factors potentially related to the spread of resistant bacteria in outpatients are sparse. Stool samples were obtained from 206 healthy couples in a community setting in Southern Germany in 2002-2003. E. coli was cultured and minimal inhibition concentrations were tested. Prevalences of E. coli resistance to commonly prescribed antibiotics according to potential risk factors were ascertained. Prevalences of ampicillin resistance were 15.7% and 19.4% for women and men, respectively. About ten percent and 15% of all isolates were resistant to cotrimoxazole and doxycycline, respectively. A partner carrying resistance was the main risk factor for being colonized with resistant E. coli. Odds ratios (95% CI) for ampicillin and cotrimoxazole resistance given carriage of resistant isolates by the partner were 6.9 (3.1-15.5) and 3.3 (1.5-18.0), respectively. Our data suggest that conjugal transmission may be more important for the spread of antibiotic resistance in the community setting than commonly suspected risk factors such as previous antibiotic intake or hospital contacts.

Genomic comparison of Escherichia coli K1 strains isolated from the cerebrospinal fluid of patients with meningitis.

PubMed

Yao, Yufeng; Xie, Yi; Kim, Kwang Sik

2006-04-01

Escherichia coli is a major cause of enteric/diarrheal diseases, urinary tract infections, and sepsis. E. coli K1 is the leading gram-negative organism causing neonatal meningitis, but the microbial basis of E. coli K1 meningitis is incompletely understood. Here we employed comparative genomic hybridization to investigate 11 strains of E. coli K1 isolated from the cerebrospinal fluid (CSF) of patients with meningitis. These 11 strains cover the majority of common O serotypes in E. coli K1 isolates from CSF. Our data demonstrated that these 11 strains of E. coli K1 can be categorized into two groups based on their profile for putative virulence factors, lipoproteins, proteases, and outer membrane proteins. Of interest, we showed that some open reading frames (ORFs) encoding the type III secretion system apparatus were found in group 2 strains but not in group 1 strains, while ORFs encoding the general secretory pathway are predominant in group 1 strains. These findings suggest that E. coli K1 strains isolated from CSF can be divided into two groups and these two groups of E. coli K1 may utilize different mechanisms to induce meningitis.

Prevalence of Campylobacter spp., Escherichia coli, and Salmonella serovars in retail chicken, turkey, pork, and beef from the Greater Washington, D.C., area.

PubMed

Zhao, C; Ge, B; De Villena, J; Sudler, R; Yeh, E; Zhao, S; White, D G; Wagner, D; Meng, J

2001-12-01

A total of 825 samples of retail raw meats (chicken, turkey, pork, and beef) were examined for the presence of Escherichia coli and Salmonella serovars, and 719 of these samples were also tested for Campylobacter spp. The samples were randomly obtained from 59 stores of four supermarket chains during 107 sampling visits in the Greater Washington, D.C., area from June 1999 to July 2000. The majority (70.7%) of chicken samples (n = 184) were contaminated with Campylobacter, and a large percentage of the stores visited (91%) had Campylobacter-contaminated chickens. Approximately 14% of the 172 turkey samples yielded Campylobacter, whereas fewer pork (1.7%) and beef (0.5%) samples were positive for this pathogen. A total of 722 Campylobacter isolates were obtained from 159 meat samples; 53.6% of these isolates were Campylobacter jejuni, 41.3% were Campylobacter coli, and 5.1% were other species. Of the 212 chicken samples, 82 (38.7%) yielded E. coli, while 19.0% of the beef samples, 16.3% of the pork samples, and 11.9% of the turkey samples were positive for E. coli. However, only 25 (3.0%) of the retail meat samples tested were positive for Salmonella. Significant differences in the bacterial contamination rates were observed for the four supermarket chains. This study revealed that retail raw meats are often contaminated with food-borne pathogens; however, there are marked differences in the prevalence of such pathogens in different meats. Raw retail meats are potential vehicles for transmitting food-borne diseases, and our findings stress the need for increased implementation of hazard analysis of critical control point (HACCP) and consumer food safety education efforts.

Prevalence of Campylobacter spp., Escherichia coli, and Salmonella Serovars in Retail Chicken, Turkey, Pork, and Beef from the Greater Washington, D.C., Area

PubMed Central

Zhao, Cuiwei; Ge, Beilei; De Villena, Juan; Sudler, Robert; Yeh, Emily; Zhao, Shaohua; White, David G.; Wagner, David; Meng, Jianghong

2001-01-01

A total of 825 samples of retail raw meats (chicken, turkey, pork, and beef) were examined for the presence of Escherichia coli and Salmonella serovars, and 719 of these samples were also tested for Campylobacter spp. The samples were randomly obtained from 59 stores of four supermarket chains during 107 sampling visits in the Greater Washington, D.C., area from June 1999 to July 2000. The majority (70.7%) of chicken samples (n = 184) were contaminated with Campylobacter, and a large percentage of the stores visited (91%) had Campylobacter-contaminated chickens. Approximately 14% of the 172 turkey samples yielded Campylobacter, whereas fewer pork (1.7%) and beef (0.5%) samples were positive for this pathogen. A total of 722 Campylobacter isolates were obtained from 159 meat samples; 53.6% of these isolates were Campylobacter jejuni, 41.3% were Campylobacter coli, and 5.1% were other species. Of the 212 chicken samples, 82 (38.7%) yielded E. coli, while 19.0% of the beef samples, 16.3% of the pork samples, and 11.9% of the turkey samples were positive for E. coli. However, only 25 (3.0%) of the retail meat samples tested were positive for Salmonella. Significant differences in the bacterial contamination rates were observed for the four supermarket chains. This study revealed that retail raw meats are often contaminated with food-borne pathogens; however, there are marked differences in the prevalence of such pathogens in different meats. Raw retail meats are potential vehicles for transmitting food-borne diseases, and our findings stress the need for increased implementation of hazard analysis of critical control point (HACCP) and consumer food safety education efforts. PMID:11722889

High Diversity of Antimicrobial Resistance Genes, Class 1 Integrons, and Genotypes of Multidrug-Resistant Escherichia coli in Beef Carcasses.

PubMed

Chen, Chih-Ming; Ke, Se-Chin; Li, Chia-Ru; Wu, Ying-Chen; Chen, Ter-Hsin; Lai, Chih-Ho; Wu, Xin-Xia; Wu, Lii-Tzu

2017-10-01

Multidrug-resistant Escherichia coli can contaminate food meat during processing and cause human infection. Phenotypic and genotypic characterization of the antimicrobial resistance were conducted for 45 multidrug-resistant E. coli isolates from 208 samples of beef carcasses. The mechanisms of resistance were evaluated using polymerase chain reaction and sequencing methods, and the clonal relationship among isolates was evaluated using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Different variants of bla, tet, flo, dfrA, and aadA genes were detected in most of the strains resistant to β-lactam, tetracycline, chloramphenicol, sulfonamides, and aminoglycosides, respectively. Extended-spectrum β-lactamase (ESBL)-producing E. coli was found in 42.2% of the 45 E. coli isolates and the most commonly detected ESBL genotypes were CTX-M group 1 and 9. Class 1 integrons with nine different arrangements of gene cassettes were present in 28 of 45 E. coli isolates. Twenty-nine PFGE groups and 24 MLST types were identified in their clonal structure. This study revealed that E. coli isolates from beef contained high diversity of antimicrobial resistance genes, integrons, and genotypes. These results highlighted the role of beef meat as a potential source for multidrug-resistant E. coli strains and the need for controlling beef safety.

Characteristics of CTX-M Extended-Spectrum β-Lactamase-Producing Escherichia coli Strains Isolated from Multiple Rivers in Southern Taiwan

PubMed Central

Chen, Po-An; Hung, Chih-Hsin; Huang, Ping-Chih; Chen, Jung-Ren; Huang, I-Fei; Chen, Wan-Ling; Chiou, Yee-Hsuan; Hung, Wan-Yu

2016-01-01

Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli sequence type ST131 has emerged as the leading cause of community-acquired urinary tract infections and bacteremia worldwide. Whether environmental water is a potential reservoir of these strains remains unclear. River water samples were collected from 40 stations in southern Taiwan from February to August 2014. PCR assay and multilocus sequence typing (MLST) analysis were conducted to determine the CTX-M group and sequence type, respectively. In addition, we identified the seasonal frequency of ESBL-producing E. coli strains and their geographical relationship with runoffs from livestock and poultry farms between February and August 2014. ESBL-producing E. coli accounted for 30% of the 621 E. coli strains isolated from river water in southern Taiwan. ESBL-producing E. coli ST131 was not detected among the isolates. The most commonly detected strain was E. coli CTX-M group 9. Among the 92 isolates selected for MLST analysis, the most common ESBL-producing clonal complexes were ST10 and ST58. The proportion of ESBL-producing E. coli was significantly higher in areas with a lower river pollution index (P = 0.025) and regions with a large number of chickens being raised (P = 0.013). ESBL-producing E. coli strains were commonly isolated from river waters in southern Taiwan. The most commonly isolated ESBL-producing clonal complexes were ST10 and ST58, which were geographically related to chicken farms. ESBL-producing E. coli ST131, the major clone causing community-acquired infections in Taiwan and worldwide, was not detected in river waters. PMID:26773082

Characteristics of CTX-M Extended-Spectrum β-Lactamase-Producing Escherichia coli Strains Isolated from Multiple Rivers in Southern Taiwan.

PubMed

Chen, Po-An; Hung, Chih-Hsin; Huang, Ping-Chih; Chen, Jung-Ren; Huang, I-Fei; Chen, Wan-Ling; Chiou, Yee-Hsuan; Hung, Wan-Yu; Wang, Jiun-Ling; Cheng, Ming-Fang

2016-01-15

Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli sequence type ST131 has emerged as the leading cause of community-acquired urinary tract infections and bacteremia worldwide. Whether environmental water is a potential reservoir of these strains remains unclear. River water samples were collected from 40 stations in southern Taiwan from February to August 2014. PCR assay and multilocus sequence typing (MLST) analysis were conducted to determine the CTX-M group and sequence type, respectively. In addition, we identified the seasonal frequency of ESBL-producing E. coli strains and their geographical relationship with runoffs from livestock and poultry farms between February and August 2014. ESBL-producing E. coli accounted for 30% of the 621 E. coli strains isolated from river water in southern Taiwan. ESBL-producing E. coli ST131 was not detected among the isolates. The most commonly detected strain was E. coli CTX-M group 9. Among the 92 isolates selected for MLST analysis, the most common ESBL-producing clonal complexes were ST10 and ST58. The proportion of ESBL-producing E. coli was significantly higher in areas with a lower river pollution index (P = 0.025) and regions with a large number of chickens being raised (P = 0.013). ESBL-producing E. coli strains were commonly isolated from river waters in southern Taiwan. The most commonly isolated ESBL-producing clonal complexes were ST10 and ST58, which were geographically related to chicken farms. ESBL-producing E. coli ST131, the major clone causing community-acquired infections in Taiwan and worldwide, was not detected in river waters. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Biological and Physicochemical Wastewater Treatment Processes Reduce the Prevalence of Virulent Escherichia coli

PubMed Central

Biswal, Basanta Kumar; Mazza, Alberto; Masson, Luke; Gehr, Ronald

2013-01-01

Effluents discharged from wastewater treatment plants are possible sources of pathogenic bacteria, including Escherichia coli, in the freshwater environment, and determining the possible selection of pathogens is important. This study evaluated the impact of activated sludge and physicochemical wastewater treatment processes on the prevalence of potentially virulent E. coli. A total of 719 E. coli isolates collected from four municipal plants in Québec before and after treatment were characterized by using a customized DNA microarray to determine the impact of treatment processes on the frequency of specific pathotypes and virulence genes. The percentages of potentially pathogenic E. coli isolates in the plant influents varied between 26 and 51%, and in the effluents, the percentages were 14 to 31%, for a reduction observed at all plants ranging between 14 and 45%. Pathotypes associated with extraintestinal pathogenic E. coli (ExPEC) were the most abundant at three of the four plants and represented 24% of all isolates, while intestinal pathogenic E. coli pathotypes (IPEC) represented 10% of the isolates. At the plant where ExPEC isolates were not the most abundant, a large number of isolates were classified as both ExPEC and IPEC; overall, 6% of the isolates were classified in both groups, with the majority being from the same plant. The reduction of the proportion of pathogenic E. coli could not be explained by the preferential loss of one virulence gene or one type of virulence factor; however, the quinolone resistance gene (qnrS) appears to enhance the loss of virulence genes, suggesting a mechanism involving the loss of pathogenicity islands. PMID:23160132

Examination of the Source and Extended Virulence Genotypes of Escherichia coli Contaminating Retail Poultry Meat

PubMed Central

Johnson, Timothy J.; Logue, Catherine M.; Wannemuehler, Yvonne; Kariyawasam, Subhashinie; Doetkott, Curt; DebRoy, Chitrita; White, David G.

2009-01-01

Abstract Extraintestinal pathogenic Escherichia coli (ExPEC) are major players in human urinary tract infections, neonatal bacterial meningitis, and sepsis. Recently, it has been suggested that there might be a zoonotic component to these infections. To determine whether the E. coli contaminating retail poultry are possible extraintestinal pathogens, and to ascertain the source of these contaminants, they were assessed for their genetic similarities to E. coli incriminated in colibacillosis (avian pathogenic E. coli [APEC]), E. coli isolated from multiple locations of apparently healthy birds at slaughter, and human ExPEC. It was anticipated that the retail poultry isolates would most closely resemble avian fecal E. coli since only apparently healthy birds are slaughtered, and fecal contamination of carcasses is the presumed source of meat contamination. Surprisingly, this supposition proved incorrect, as the retail poultry isolates exhibited gene profiles more similar to APEC than to fecal isolates. These isolates contained a number of ExPEC-associated genes, including those associated with ColV virulence plasmids, and many belonged to the B2 phylogenetic group, known to be virulent in human hosts. Additionally, E. coli isolated from the crops and gizzards of apparently healthy birds at slaughter also contained a higher proportion of ExPEC-associated genes than did the avian fecal isolates examined. Such similarities suggest that the widely held beliefs about the sources of poultry contamination may need to be reassessed. Also, the presence of ExPEC-like clones on retail poultry meat means that we cannot yet rule out poultry as a source of ExPEC human disease. PMID:19580453

Susceptibility of Escherichia coli isolated from uteri of postpartum dairy cows to antibiotic and environmental bacteriophages. Part II: In vitro antimicrobial activity evaluation of a bacteriophage cocktail and several antibiotics.

PubMed

Santos, T M A; Gilbert, R O; Caixeta, L S; Machado, V S; Teixeira, L M; Bicalho, R C

2010-01-01

The use of pathogenic-specific antimicrobials, as proposed by bacteriophage therapy, is expected to reduce the incidence of resistance development. Eighty Escherichia coli isolated from uteri of Holstein dairy cows were phenotypically characterized for antimicrobial resistance to ampicillin, ceftiofur, chloramphenicol, florfenicol, spectinomycin, streptomycin, and tetracycline by broth microdilution method. The lytic activity of a bacteriophage cocktail against all isolates was performed by a similar method. Additionally, the effect of different concentrations of antimicrobials and multiplicities of infections (MOI) of the bacteriophage cocktail on E. coli growth curve was measured. Isolates exhibited resistance to ampicillin (33.7%), ceftiofur (1.2%), chloramphenicol (100%), and florfenicol (100%). All strains were resistant to at least 2 of the antimicrobial agents tested; multidrug resistance (>or=3 of 7 antimicrobials tested) was observed in 35% of E. coli isolates. The major multidrug resistance profile was found for ampicillin-chloramphenicol-florfenicol, which was observed in more than 96.4% of the multidrug-resistant isolates. The bacteriophage cocktail preparation showed strong antimicrobial activity against multidrug-resistant E. coli. Multiplicity of infection as low as 10(-4) affected the growth of the E. coli isolates. The ratio of 10 bacteriophage particles per bacterial cell (MOI=10(1)) was efficient in inhibiting at least 50% of all isolates. Higher MOI should be tested in future in vitro studies to establish ratios that completely inhibit bacterial growth during longer periods. All isolates resistant to florfenicol were resistant to chloramphenicol and, because florfenicol was recently introduced into veterinary clinics, this finding suggests that the selection pressure of chloramphenicol, as well as other antimicrobials, may still play a relevant role in the emergence and dissemination of florfenicol resistance in E. coli. The bacteriophage cocktail had a notable capacity to inhibit the in vitro growth of E. coli isolates, and it may be an attractive alternative to conventional treatment of metritis by reducing E. coli in uteri of postpartum dairy cows. Copyright 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Reversion of High-level Mecillinam Resistance to Susceptibility in Escherichia coli During Growth in Urine.

PubMed

Thulin, Elisabeth; Thulin, Måns; Andersson, Dan I

2017-09-01

Mecillinam (amdinocillin) is a β-lactam antibiotic used to treat uncomplicated urinary tract infections (UTIs). We have previously shown that inactivation of the Escherichia coli cysB gene is the major cause of mecillinam resistance (Mec R ) in clinical isolates. In this study, we used different E. coli strains (laboratory and clinical isolates) that were Mec R due to cysB mutations to determine how mecillinam susceptibility was affected during growth in urine compared to growth in the commonly used growth medium Mueller Hinton (MHB). We also examined mecillinam susceptibility when bacteria were grown in urine obtained from 48 different healthy volunteers. Metabolome analysis was done on the urine samples and the association between the mecillinam susceptibility patterns of the bacteria and urine metabolite levels was studied. Two major findings with clinical significance are reported. First, Mec R E. coli cysB mutant strains (both laboratory and clinical isolates) were always more susceptible to mecillinam when grown in urine as compared to laboratory medium, with many strains showing complete phenotypic susceptibility in urine. Second, the degree of reversion to susceptibility varied between urine samples obtained from different individuals. This difference was correlated with osmolality such that in urine with low osmolality the Mec R mutants were more susceptible to mecillinam than in urine with high osmolality. This is the first example describing conditional resistance where a genetically stable antibiotic resistance can be phenotypically reverted to susceptibility by metabolites present in urine. These findings have several important clinical implications regarding the use of mecillinam to treat UTIs. First, they suggest that mecillinam can be used to treat also those clinical strains that are identified as Mec R in standard laboratory tests. Second, the results suggest that testing of mecillinam susceptibility in the laboratory ought to be performed in media that mimics urine to obtain clinically relevant susceptibility testing results. Third, these findings imply that changes in patient behavior, such as increased water intake or use of diuretics to reduce urine osmolality and increased intake of cysteine, might induce antibiotic susceptibility in an infecting Mec R E. coli strain and thereby increase treatment efficiency. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

The association between occurrence of plasmid-mediated quinolone resistance and ciprofloxacin resistance in Escherichia coli isolates of different origins.

PubMed

Yang, Tong; Zeng, Zhenling; Rao, Lili; Chen, Xiaojie; He, Dandan; Lv, Luchao; Wang, Jing; Zeng, Li; Feng, Minsha; Liu, Jian-Hua

2014-05-14

This study was performed to determine the prevalence of plasmid-mediated quinolone resistance (PMQR) determinants and characterize the ciprofloxacin resistance in Escherichia coli isolated from different sources in China. PMQR determinants were detected by PCR amplification and sequencing in 2297 E. coli isolates randomly collected from animals, food and humans during 2004 to 2011. MICs of ciprofloxacin were determined by agar dilution method. Of the 2297 E. coli isolates, 43.6% harbored at least one PMQR gene. The most common PMQR gene was oqxAB (29.3%), followed by qnr (13.6%), aac(6')-Ib-cr (11.6%), and qepA (3.3%). 12.0% isolates carried two or more PMQR genes. The prevalence of PMQR genes in food animal isolates increased over time, from 38.7% in 2004 to 69.8% in 2011. The prevalence of PMQR/ciprofloxacin resistance among isolates from pig, chicken, duck, companion animals, animal food and human volunteers were 65.2%/69.6%, 42.4%/60.0%, 59.4%/65.0%, 28.6%/57.5%, 29.3%/25.6%, and 14.0/8.7%, respectively. Most isolates carrying qnr along showed susceptible to ciprofloxacin, and only 21.6% the isolates exhibited resistance to ciprofloxacin, which was significantly lower than those carrying other PMQR genes (65.2-89.9%) and those that do not (43.1%) (p<0.01). In conclusion, high frequency of ciprofloxacin resistance and PMQR genes was observed among E. coli isolates of different origins in China, with oqxAB being the most frequent. qnr-positive E. coli isolates have relatively low ciprofloxacin resistance rate compared with other PMQR determinants-carrying isolates and PMQR-negative isolates. Copyright © 2014. Published by Elsevier B.V.

Study of antagonistic effects of Lactobacillus strains as probiotics on multi drug resistant (MDR) bacteria isolated from urinary tract infections (UTIs).

PubMed

Naderi, Atiyeh; Kasra-Kermanshahi, Roha; Gharavi, Sara; Imani Fooladi, Abbas Ali; Abdollahpour Alitappeh, Meghdad; Saffarian, Parvaneh

2014-03-01

Urinary tract infection (UTI) caused by bacteria is one of the most frequent infections in human population. Inappropriate use of antibiotics, often leads to appearance of drug resistance in bacteria. However, use of probiotic bacteria has been suggested as a partial replacement. This study was aimed to assess the antagonistic effects of Lactobacillus standard strains against bacteria isolated from UTI infections. Among 600 samples; those with ≥10,000 cfu/ml were selected as UTI positive samples. Enterococcus sp., Klebsiella pneumoniae, Enterobacter sp., and Escherichia coli were found the most prevalent UTI causative agents. All isolates were screened for multi drug resistance and subjected to the antimicrobial effects of three Lactobacillus strains by using microplate technique and the MICs amounts were determined. In order to verify the origin of antibiotic resistance of isolates, plasmid curing using ethidium bromide and acridine orange was carried out. No antagonistic activity in Lactobacilli suspension was detected against test on Enterococcus and Enterobacter strains and K. pneumoniae, which were resistant to most antibiotics. However, an inhibitory effect was observed for E. coli which were resistant to 8-9 antibiotics. In addition, L. casei was determined to be the most effective probiotic. RESULTS from replica plating suggested one of the plasmids could be related to the gene responsible for ampicillin resistance. Treatment of E. coli with probiotic suspension was not effective on inhibition of the plasmid carrying hypothetical ampicillin resistant gene. Moreover, the plasmid profiles obtained from probiotic-treated isolates were identical to untreated isolates.

Characterisation of extended-spectrum β-lactamase and AmpC β-lactamase-producing Enterobacteriaceae isolated from companion animals in New Zealand.

PubMed

Karkaba, A; Grinberg, A; Benschop, J; Pleydell, E

2017-03-01

To assess the occurrence of, and characterise, extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase (AmpC)-producing Enterobacteriaceae isolated by veterinary diagnostic laboratories from infection sites in companion animals in New Zealand. Selected Enterobacteriaceae isolates were submitted by seven New Zealand veterinary diagnostic laboratories. They were isolated from infection sites in companion animals between June 2012 and June 2013, and were resistant to amoxicillin-clavulanic acid, fluoroquinolones, or any combination of two or more antimicrobials. Based on disk diffusion test results, the isolates were phenotypically categorised according to production of ESBL and AmpC. Genes for ESBL and AmpC production were amplified by PCR and sequenced. Escherichia coli isolates were also typed by multilocus sequence typing. A total of 115 isolates matching the inclusion criteria were obtained from the participating laboratories, of which 74 (64%) originated from dogs and 29 (25%) from cats. Seven bacterial species were identified, of which E. coli was the most common (87/115, 76%). Of the 115 isolates, 10 (9%) expressed the ESBL phenotype, 43 (37%) the AmpC phenotype, and seven (6%) both ESBL and AmpC phenotypes. Of the 60 ESBL and AmpC-producing isolates, 36 (60%) were E. coli. Amongst these isolates, 27/60 (45%) were classified as multidrug resistant, compared with 15/55 (27%) non-ESBL or AmpC-producing isolates (p<0.01). Ninety five isolates were resistant to amoxicillin-clavulanic acid and 58 (61%) of these were ESBL or AmpC-producing. The predominant ESBL genes were bla CTX-M-14 and bla CTX-M-15 , and the dominant plasmid-encoded AmpC gene was bla CMY-2 . Thirty-eight E. coli multilocus sequence types (ST) were identified, and the most prevalent were ST12 (12/89, 13%), ST131 (6/89, 7%) and ST648 (6/89, 7%). ESBL and AmpC-producing isolates accounted for 35/1,082 (3.2%) of the Enterobacteriaceae isolated by one laboratory network over the study period. ESBL and AmpC-producing Enterobacteriaceae were associated with clinical infections in companion animals in New Zealand, and were often multidrug resistant. In this study, these organisms accounted for <5% of all Enterobacteriaceae isolated from infection sites by one laboratory network, but their prevalence among isolates resistant to amoxicillin-clavulanic acid was 61%. Therefore routine secondary testing for ESBL and AmpC production by Enterobacteriaceae that are resistant to amoxicillin-clavulanic acid in primary testing could improve the accuracy of definitive antimicrobial therapy in companion animals in New Zealand.

Characterisation of Commensal Escherichia coli Isolated from Apparently Healthy Cattle and Their Attendants in Tanzania

PubMed Central

Mtambo, Madundo M. A.; Muhairwa, Amandus P.; Lupindu, Athumani M.; Olsen, John E.

2016-01-01

While pathogenic types of Escherichia coli are well characterized, relatively little is known about the commensal E. coli flora. In the current study, antimicrobial resistance in commensal E. coli and distribution of ERIC-PCR genotypes among isolates of such bacteria from cattle and cattle attendants on cattle farms in Tanzania were investigated. Seventeen E. coli genomes representing different ERIC-PCR types of commensal E. coli were sequenced in order to determine their possible importance as a reservoir for both antimicrobial resistance genes and virulence factors. Both human and cattle isolates were highly resistant to tetracycline (40.8% and 33.1%), sulphamethazole-trimethoprim (49.0% and 8.8%) and ampicillin (44.9% and 21.3%). However, higher proportion of resistant E. coli and higher frequency of resistance to more than two antimicrobials was found in isolates from cattle attendants than isolates from cattle. Sixteen out of 66 ERIC-PCR genotypes were shared between the two hosts, and among these ones, seven types contained isolates from cattle and cattle attendants from the same farm, suggesting transfer of strains between hosts. Genome-wide analysis showed that the majority of the sequenced cattle isolates were assigned to phylogroups B1, while human isolates represented phylogroups A, C, D and E. In general, in silico resistome and virulence factor identification did not reveal differences between hosts or phylogroups, except for lpfA and iss found to be cattle and B1 phylogroup specific. The most frequent plasmids replicon genes found in strains from both hosts were of IncF type, which are commonly associated with carriage of antimicrobial and virulence genes. Commensal E. coli from cattle and attendants were found to share same genotypes and to carry antimicrobial resistance and virulence genes associated with both intra and extraintestinal E. coli pathotypes. PMID:27977751

Clinical Epidemiology and Molecular Analysis of Extended-Spectrum-β-Lactamase-Producing Escherichia coli in Nepal: Characteristics of Sequence Types 131 and 648

PubMed Central

Sherchan, Jatan Bahadur; Miyoshi-Akiyama, Tohru; Ohmagari, Norio; Kirikae, Teruo; Nagamatsu, Maki; Tojo, Masayoshi; Ohara, Hiroshi; Sherchand, Jeevan B.; Tandukar, Sarmila

2015-01-01

Recently, CTX-M-type extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli strains have emerged worldwide. In particular, E. coli with O antigen type 25 (O25) and sequence type 131 (ST131), which is often associated with the CTX-M-15 ESBL, has been increasingly reported globally; however, epidemiology reports on ESBL-producing E. coli in Asia are limited. Patients with clinical isolates of ESBL-producing E. coli in the Tribhuvan University teaching hospital in Kathmandu, Nepal, were included in this study. Whole-genome sequencing of the isolates was conducted to analyze multilocus sequence types, phylotypes, virulence genotypes, O25b-ST131 clones, and distribution of acquired drug resistance genes. During the study period, 105 patients with ESBL-producing E. coli isolation were identified, and the majority (90%) of these isolates were CTX-M-15 positive. The most dominant ST was ST131 (n = 54; 51.4%), followed by ST648 (n = 15; 14.3%). All ST131 isolates were identified as O25b-ST131 clones, subclone H30-Rx. Three ST groups (ST131, ST648, and non-ST131/648) were compared in further analyses. ST648 isolates had a proportionally higher resistance to non-β-lactam antibiotics and featured drug-resistant genes more frequently than ST131 or non-ST131/648 isolates. ST131 possessed the most virulence genes, followed by ST648. The clinical characteristics were similar among groups. More than 38% of ESBL-producing E. coli isolates were from the outpatient clinic, and pregnant patients comprised 24% of ESBL-producing E. coli cases. We revealed that the high resistance of ESBL-producing E. coli to multiple classes of antibiotics in Nepal is driven mainly by CTX-M-producing ST131 and ST648. Their immense prevalence in the communities is a matter of great concern. PMID:25824221

[Isolation of Escherichia coli O128:HNM harboring stx2f gene from diarrhea patients].

PubMed

Isobe, Junko; Kimata, Keiko; Shimojima, Masahiro; Hosorogi, Shiho; Tanaka, Daisuke; Gyobu, Yotaku

2004-12-01

Shiga-like-toxin-producing Esherichia coli O128:HNM were isolated from feces of a one-year-old boy with diarrhea and abdominal pain on July, 2002, and a 11-month-old girl with diarrhea and fever on June, 1997. None of other enteropathogenic bacteria including Salmonella were isolated. E. coli O128:HNM isolates from both patients carry stx2f and eaeA gene, but not stx1, stx2, aggR, bfpA, esth, estp, invE, astA, ureC and hlyA gene. As far as we know, this may be the first report indicating that E. coli O128:HNM carrying stx2f gene were isolated from patients in Japan.

Sources of Escherichia coli O157 and experiences over the past 15 years in Sheffield, UK.

PubMed

Chapman, P A

2000-01-01

In the first documented outbreak of HC caused by Escherichia coli O157, which occurred in the North-west USA in 1982, there was a strong association between infection and prior consumption of ground beef from a chain of fast food restaurants. Foods of bovine origin, including beef, milk and dairy products, have since been implicated in many outbreaks of infection world-wide. Investigations during the course of outbreaks, or at random, have shown that cattle are a major reservoir of E. coli O157. E. coli O157 was isolated from cattle at slaughter in Sheffield in 1987, this being the first isolation from cattle in the UK. Following a cluster of cases in May/June 1992, an abattoir study showed the organism to be present in 4% of cattle at slaughter and on up to a third of carcasses from rectal swab-positive animals. E. coli O157 was isolated from a food source (unpasteurized milk), for the first time in the UK, in Sheffield in May 1993. During surveillance in 1995-6, E. coli O157 was isolated from 15.7% of cattle, with a monthly prevalence which varied from 5 to 37%. E. coli O157 was also isolated from 2.2% of sheep. During surveillance in 1996, E. coli O157 was isolated from 5.9% of samples of lamb products and from 1.5% of samples of beef products, despite the prevalence in cattle being much higher than in sheep. Work is in progress to try to explain this higher prevalence in lamb products. During 1997 in Sheffield, the only cases of E. coli O157 for which a confirmed source was established were associated with direct animal contact on farm visits. During on-farm investigations of these cases, E. coli O157 was isolated from faecal samples from adult cattle, calves, three different breeds of sheep, two different breeds of pigs, goats and a pony.

Comparison of ESBL – And AmpC Producing Enterobacteriaceae and Methicillin-Resistant Staphylococcus aureus (MRSA) Isolated from Migratory and Resident Population of Rooks (Corvus frugilegus) in Austria

PubMed Central

Mehinagic, Kemal; Rosengarten, Renate; Hoelzl, Franz; Knauer, Felix; Walzer, Chris

2013-01-01

In order to test whether rooks (Corvus frugilegus) represent good indicators for the potential circulation of antibiotics in their native habitat, two populations with different migratory behavior were tested for the presence of beta-lactamase producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA). In all, 54 and 102 samples of fresh feces of a migratory and a resident population were investigated. A total of 24 and 3 cefotaxime-resistant enterobacterial isolates were obtained from the migratory and resident population, respectively. In these isolates CTX-M-1 (n = 15), CTX-M-3 (n = 3), and CTX-M-15 (n = 3) genes were detected. TEM-1 and OXA-1 were associated with CTX-M in 3 and 2 isolates, respectively. In two E. coli isolates CMY-2 could be detected, where from one isolate displayed an overexpression of chromosomal AmpC as well. Among E. coli isolates the most common phylogenetic group was A (n = 11) and ST1683 (n = 5). In one E. coli of B2-ST131 the rfbO25b locus was detected. Three Enterobacter isolates were stably derepressed AmpC-producers. In five samples of the migratory population, PVL positive MRSA could be isolated. Two isolates were typed SCCmec IVa, spa type t127, and ST1. Three isolates carried a SCCmec type IVc, with spa type t852 and ST22. The highly significant difference of the occurrence of antibiotic resistance between the migratory population from eastern Europe compared to resident population in our study indicates that rooks may be good indicator species for the evaluation of environmental contamination with antibiotic resistant bacteria, especially due to their ecology, foraging behavior and differing migratory behavior. PMID:24391878

Enterohemorrhagic Escherichia coli O157 in milk and dairy products from Libya: Isolation and molecular identification by partial sequencing of 16S rDNA

PubMed Central

Garbaj, Aboubaker M.; Awad, Enas M.; Azwai, Salah M.; Abolghait, Said K.; Naas, Hesham T.; Moawad, Ashraf A.; Gammoudi, Fatim T.; Barbieri, Ilaria; Eldaghayes, Ibrahim M.

2016-01-01

Aim: The aim of this work was to isolate and molecularly identify enterohemorrhagic Escherichia coli (EHEC) O157 in milk and dairy products in Libya, in addition; to clear the accuracy of cultural and biochemical identification as compared with molecular identification by partial sequencing of 16S rDNA for the existing isolates. Materials and Methods: A total of 108 samples of raw milk (cow, she-camel, and goat) and locally made dairy products (fermented cow’s milk, Maasora, Ricotta and ice cream) were collected from some regions (Janzour, Tripoli, Kremiya, Tajoura and Tobruk) in Libya. Samples were subjected to microbiological analysis for isolation of E. coli that was detected by conventional cultural and molecular method using polymerase chain reaction and partial sequencing of 16S rDNA. Results: Out of 108 samples, only 27 isolates were found to be EHEC O157 based on their cultural characteristics (Tellurite-Cefixime-Sorbitol MacConkey) that include 3 isolates from cow’s milk (11%), 3 isolates from she-camel’s milk (11%), two isolates from goat’s milk (7.4%) and 7 isolates from fermented raw milk samples (26%), isolates from fresh locally made soft cheeses (Maasora and Ricotta) were 9 (33%) and 3 (11%), respectively, while none of the ice cream samples revealed any growth. However, out of these 27 isolates, only 11 were confirmed to be E. coli by partial sequencing of 16S rDNA and E. coli O157 Latex agglutination test. Phylogenetic analysis revealed that majority of local E. coli isolates were related to E. coli O157:H7 FRIK944 strain. Conclusion: These results can be used for further studies on EHEC O157 as an emerging foodborne pathogen and its role in human infection in Libya. PMID:27956766

Influence of Detection Methods in Characterizing Escherichia coli O157:H7 in Raw Goat Meat Using Conventional and Molecular Methods.

PubMed

Tabashsum, Zajeba; Nazneen, Mafruha; Ahsan, C R; Bari, M L; Yasmin, M

2016-01-01

　Presence of Escherichia coli O157:H7 on fresh goat meat samples (n= 40) of Dhaka city was analyzed using conventional and molecular methods. A total of 86 presumptive E. coli O157:H7 colonies were isolated from 60% of the samples using selective agar plating method. After conventional biochemical assay followed by API 20E assay, only 11 isolates were found to be E. coli O157:H7. Further serological test identified only four isolates that has strong agglutination reaction against anti-H7 sensitized latex. The biochemically and serologically confirmed isolates were then screened for major virulence factors include eaeA, rfbE, fliC, stx1 and stx2 genes by PCR. PCR analysis of positive isolates showed, 10 isolates were eaeA and rfbE genes positive but fliC gene was only in six, indicating that these isolates were H7 positive with flagellum antigens which might not expressed or detected in serotyping tests. Multiplex PCR against eaeA, stx1 and stx2 genes of the isolates showed similar results as when done individually. These results revealed that only 7% of the primary presumptive E. coli O157:H7 was found to be stx producing E. coli O157:H7 and thus greatly influenced the detection of the pathogen in meat samples.

Integron, Plasmid and Host Strain Characteristics of Escherichia coli from Humans and Food Included in the Norwegian Antimicrobial Resistance Monitoring Programs.

PubMed

Sunde, Marianne; Simonsen, Gunnar Skov; Slettemeås, Jannice Schau; Böckerman, Inger; Norström, Madelaine

2015-01-01

Antimicrobial resistant Escherichia coli (n=331) isolates from humans with bloodstream infections were investigated for the presence of class 1 and class 2 integrons. The integron cassettes arrays were characterized and the findings were compared with data from similar investigations on resistant E. coli from meat and meat products (n=241) produced during the same time period. All isolates were obtained from the Norwegian monitoring programs for antimicrobial resistance in human pathogens and in the veterinary sector. Methods used included PCR, sequencing, conjugation experiments, plasmid replicon typing and subtyping, pulsed-field-gel-electrophoresis and serotyping. Integrons of class 1 and 2 occurred significantly more frequently among human isolates; 45.4% (95% CI: 39.9-50.9) than among isolates from meat; 18% (95% CI: 13.2 -23.3), (p<0.01, Chi-square test). Identical cassette arrays including dfrA1-aadA1, aadA1, dfrA12-orfF-aadA2, oxa-30-aadA1 (class 1 integrons) and dfrA1-sat1-aadA1 (class 2 integrons) were detected from both humans and meat. However, the most prevalent cassette array in human isolates, dfrA17-aadA5, did not occur in isolates from meat, suggesting a possible linkage between this class 1 integron and a subpopulation of E. coli adapted to a human host. The drfA1-aadA1 and aadA1 class 1 integrons were found frequently in both human and meat isolates. These isolates were subjected to further studies to investigate similarities with regard to transferability, plasmid and host strain characteristics. We detected incF plasmids with pMLST profile F24:A-:B1 carrying drfA1-aadA1 integrons in isolates from pork and in a more distantly related E. coli strain from a human with septicaemia. Furthermore, we showed that most of the class 1 integrons with aadA1 were located on incF plasmids with pMLST profile F51:A-:B10 in human isolates. The plasmid was present in unrelated as well as closely related host strains, demonstrating that dissemination of this integron also could be attributed to clonal spread. In conclusion, among the systematically collected isolates from two different sources, some significant differences concerning integron prevalence and integron variants were observed. However, closely related plasmids as vehicles for specific class 1 integrons in isolates from meat and from a human with bloodstream infection were found. The occurrence of similar multi-resistance plasmids in bacteria from a food source and from a human clinical sample highlights the possible role of meat as a source of resistance elements for pathogenic bacteria.

Cloacael Carriage and Multidrug Resistance Escherichia coli O157:H7 from Poultry Farms, Eastern Ethiopia

PubMed Central

Shecho, Mude; Muktar, Yimer

2017-01-01

A cross-sectional study was carried out to determine antimicrobial drug resistance patterns of E. coli O157:H7 isolates and estimate the level of the pathogen. A total of 194 cloacae swab samples were collected randomly in two poultry farms. Standard cultural, biochemical, and serological (latex agglutination) methods were used to isolate E. coli O157:H7. The isolates were subjected to antimicrobial susceptibility testing using disc diffusion method. Out of 194 cloacae samples examined, 13.4% (n = 26) were found to be positive for E. coli O157:H7. The finding indicated differences in E. coli O157:H7 infection among the different risk factors. Chicken from Adele Poultry Farm showed higher E. coli O157:H7 infection (OR = 3.89) than Haramaya University poultry farm and young birds had more infection (OR = 4.62) than adult birds. Of the total 14 antimicrobials included in the panel of study, the susceptibility results were varied with 96.15% and 0% E. coli O157:H7 isolates expressing resistance to erythromycin, clindamycin, spectinomycin, and ciprofloxacin, respectively. Multidrug resistance to more than two antimicrobial agents was detected in 24 (92.30%) of the isolates. The study showed high presence of antimicrobial resistant isolates of E. coli O157:H7. Further study is required to better understand the ecology and evolution of bacterial resistance to antimicrobial agents. PMID:28349121

Cloacael Carriage and Multidrug Resistance Escherichia coli O157:H7 from Poultry Farms, Eastern Ethiopia.

PubMed

Shecho, Mude; Thomas, Naod; Kemal, Jelalu; Muktar, Yimer

2017-01-01

A cross-sectional study was carried out to determine antimicrobial drug resistance patterns of E. coli O157:H7 isolates and estimate the level of the pathogen. A total of 194 cloacae swab samples were collected randomly in two poultry farms. Standard cultural, biochemical, and serological (latex agglutination) methods were used to isolate E. coli O157:H7. The isolates were subjected to antimicrobial susceptibility testing using disc diffusion method. Out of 194 cloacae samples examined, 13.4% ( n = 26) were found to be positive for E. coli O157:H7. The finding indicated differences in E. coli O157:H7 infection among the different risk factors. Chicken from Adele Poultry Farm showed higher E. coli O157:H7 infection (OR = 3.89) than Haramaya University poultry farm and young birds had more infection (OR = 4.62) than adult birds. Of the total 14 antimicrobials included in the panel of study, the susceptibility results were varied with 96.15% and 0% E. coli O157:H7 isolates expressing resistance to erythromycin, clindamycin, spectinomycin, and ciprofloxacin, respectively. Multidrug resistance to more than two antimicrobial agents was detected in 24 (92.30%) of the isolates. The study showed high presence of antimicrobial resistant isolates of E. coli O157:H7. Further study is required to better understand the ecology and evolution of bacterial resistance to antimicrobial agents.

Differentiation of Campylobacter jejuni and Campylobacter coli Using Multiplex-PCR and High Resolution Melt Curve Analysis

PubMed Central

Banowary, Banya; Dang, Van Tuan; Sarker, Subir; Connolly, Joanne H.; Chenu, Jeremy; Groves, Peter; Ayton, Michelle; Raidal, Shane; Devi, Aruna; Vanniasinkam, Thiru; Ghorashi, Seyed A.

2015-01-01

Campylobacter spp. are important causes of bacterial gastroenteritis in humans in developed countries. Among Campylobacter spp. Campylobacter jejuni (C. jejuni) and C. coli are the most common causes of human infection. In this study, a multiplex PCR (mPCR) and high resolution melt (HRM) curve analysis were optimized for simultaneous detection and differentiation of C. jejuni and C. coli isolates. A segment of the hippuricase gene (hipO) of C. jejuni and putative aspartokinase (asp) gene of C. coli were amplified from 26 Campylobacter isolates and amplicons were subjected to HRM curve analysis. The mPCR-HRM was able to differentiate between C. jejuni and C. coli species. All DNA amplicons generated by mPCR were sequenced. Analysis of the nucleotide sequences from each isolate revealed that the HRM curves were correlated with the nucleotide sequences of the amplicons. Minor variation in melting point temperatures of C. coli or C. jejuni isolates was also observed and enabled some intraspecies differentiation between C. coli and/or C. jejuni isolates. The potential of PCR-HRM curve analysis for the detection and speciation of Campylobacter in additional human clinical specimens and chicken swab samples was also confirmed. The sensitivity and specificity of the test were found to be 100% and 92%, respectively. The results indicated that mPCR followed by HRM curve analysis provides a rapid (8 hours) technique for differentiation between C. jejuni and C. coli isolates. PMID:26394042

Migratory White Stork (Ciconia ciconia): A Potential Vector of the OXA-48-Producing Escherichia coli ST38 Clone in Algeria.

PubMed

Bouaziz, Amira; Loucif, Lotfi; Ayachi, Ammar; Guehaz, Karima; Bendjama, Esma; Rolain, Jean-Marc

2018-05-01

The emergence of carbapenemase-producing Enterobacteriaceae is of great concern to public health worldwide. The aim of this study was to screen for the presence of carbapenemase-producing Enterobacteriaceae in white stork (Ciconia ciconia) migratory bird stools, and to investigate their molecular support on β-lactamase production. In March 2015, 32 fecal samples of white stork were collected in the Commune of El Madher Wilaya de Batna, in eastern Algeria. Samples were subjected to selective isolation of carbapenem-resistant Enterobacteriaceae. Representative colonies were screened phenotypically for carbapenemase production. Carbapenemase-producing isolates were subjected to antibiotic susceptibility testing and extended-spectrum β-lactamase (ESBL) coproduction. β-Lactamase determinants were searched for by PCR and sequencing. Three carbapenemase-producing Escherichia coli were obtained. Only one strain was positive for ESBL production. The OXA-48-type carbapenemase-encoding gene was detected in all isolates. Screening for other β-lactamase-encoding genes showed that all isolates coexpress the bla TEM gene, whereas one of them additionally harbored the bla CTX-M-15 ESBL gene. Multilocus sequence typing results showed that two strains belonged to the sequence type 38. This work demonstrated for the first time that the migratory white stork can play an important role in the dissemination of OXA-48-producing E. coli as a potential reservoir and vector.

Detection & characterization of necrotoxin producing Escherichia coli (NTEC) from patients with urinary tract infection (UTI).

PubMed

Rahman, Helina; Deka, Manab

2014-04-01

Urinary tract infections (UTI) are a serious health problem affecting millions of people each year. Although appreciable work on various aspects of UTI including aetiology per se has been done, information on the emerging pathogens like necrotoxigenic Escherichia coli (NTEC) is largely lacking in India. In the present study E. coli isolates from patients with urinary tract infection from northeastern India were investigated for detection and characterization of NTEC. E. coli isolated and identified from urine samples of patients with UTI were serotyped. Antibiogram was determined by disc diffusion test. Plasmid profile was also determined. Virulence genes of NTEC (cnf1, cnf2, pap, aer, sfa, hly, afa) were detected by PCR assay. E.coli isolates carrying cnf gene (s) were identified as NTEC. A total of 550 E. coli were isolated and tested for the presence of cnf genes. Of these, 84 (15.27%) belonged to NTEC. The cnf1 gene was present in 52 (61.9%) isolates, cnf2 in 23 (27.4%) and 9 (10.7%) carried both cnf1 and cnf2 genes. All the NTEC strains were found to harbour the pap and aer genes. Serogroup O4 was found to be the most common among the 12 serogroups identified amongst the NTEC isolates. Majority of the isolates (96.4%) were sensitive to furazolidone and were highly resistant to ampicillin. NTEC were found to harbour different numbers of plasmids (1 to 7). No association was observed between the number of plasmids and the antibiotic resistance of the isolates. The results of the present study showed that about 15 per cent of E. coli isolates associated with UTI belonged to NTEC. More studies need to be done from other parts of the country.

Distribution of Diverse Escherichia coli between Cattle and Pasture

PubMed Central

NandaKafle, Gitanjali; Seale, Tarren; Flint, Toby; Nepal, Madhav; Venter, Stephanus N.; Brözel, Volker S.

2017-01-01

Escherichia coli is widely considered to not survive for extended periods outside the intestines of warm-blooded animals; however, recent studies demonstrated that E. coli strains maintain populations in soil and water without any known fecal contamination. The objective of this study was to investigate whether the niche partitioning of E. coli occurs between cattle and their pasture. We attempted to clarify whether E. coli from bovine feces differs phenotypically and genotypically from isolates maintaining a population in pasture soil over winter. Soil, bovine fecal, and run-off samples were collected before and after the introduction of cattle to the pasture. Isolates (363) were genotyped by uidA and mutS sequences and phylogrouping, and evaluated for curli formation (Rough, Dry, And Red, or RDAR). Three types of clusters emerged, viz. bovine-associated, clusters devoid of cattle isolates and representing isolates endemic to the pasture environment, and clusters with both. All isolates clustered with strains of E. coli sensu stricto, distinct from the cryptic species Clades I, III, IV, and V. Pasture soil endemic and bovine fecal populations had very different phylogroup distributions, indicating niche partitioning. The soil endemic population was largely comprised of phylogroup B1 and had a higher average RDAR score than other isolates. These results indicate the existence of environmental E. coli strains that are phylogenetically distinct from bovine fecal isolates, and that have the ability to maintain populations in the soil environment. PMID:28747587

Determinants of quinolone resistance in Escherichia coli causing community-acquired urinary tract infection in Bejaia, Algeria.

PubMed

Betitra, Yanat; Teresa, Vinuesa; Miguel, Viñas; Abdelaziz, Touati

2014-06-01

To investigate the mechanisms of quinolone resistance and the association with other resistance markers among Esherichia coli (E. coli) strains isolated from outpatient with urinary tract infection in north of Algeria. A total of 30 nalidixic acid-resistant E. coli isolates from outpatient with urinary tract infections from January 2010 to April 2011 in north of Algeria (Bejaia) were studied. Antimicrobial susceptibility was determined by disc diffusion assay, minimal inhibitory concentrations (MIC) of quinolone were determined by microdilution. Mutations in the Quinolone Resistance-Determining Region (QRDR) of gyrA and parC genes and screening for qnr (A, B and S) and bla genes were done by PCR and DNA sequencing. Most of the E. coli isolates (56.66%) were shown to carry mutations in gyrA and parC (gyrA: Ser83Leu + Asp87Asn and parC:Ser80Ile). While, 16.66% had only an alteration in gyrA: Ser83Leu. One isolate produced qnrB-like and two qnrS-like. Four isolates were CTX-M-15 producers associated with TEM-1 producing in one case. Co-expression of blaCTX-M-15 and qnrB was determined in one E. coli isolate. Our findings suggested the community emergence of gyrA and parC alterations and Qnr determinants that contributed to the development and spread of fluoroquinolone resistance in Algerian E. coli isolates. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Clonal diversity of extended-spectrum beta-lactamase producing Escherichia coli isolates in fecal samples of wild animals.

PubMed

Cristóvão, Filipe; Alonso, Carla Andrea; Igrejas, Gilberto; Sousa, Margarida; Silva, Vanessa; Pereira, José Eduardo; Lozano, Carmen; Cortés-Cortés, Gerardo; Torres, Carmen; Poeta, Patrícia

2017-03-01

The clonal diversity of extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli isolates from nine different species of wild animals from distinct regions of Portugal and Spain and their content in replicon plasmids were analyzed. Among the initial 53 ESBL-producing E. coli isolates that were studied (from previous studies), 28 were selected, corresponding to different animal origins with distinct ESBL types and pulsed-field gel electrophoresis (PFGE) patterns. These 28 isolates produced different ESBLs ascribed to the following families: CTX-M, SHV and TEM. The isolates were classified into three phylogenetic groups: B1 (n = 11), A (n = 10) and D (n = 7). The seven E. coli of phylogroup D were then typed by multilocus sequence typing and ascribed to four distinct sequence types: ST117, ST115, ST2001 and ST69. The clonal diversity and relationship between isolates was studied by PFGE. Lastly, the plasmids were analyzed according to their incompatibility group using the PCR-based-replicon-typing scheme. A great diversity of replicon types was identified, with up to five per isolate. Most of the CTX-M-1 and SHV-12 producing E. coli isolates carried IncI1 or IncN replicons. The diversity of ESBL-producing E. coli isolates in wild animals, which can be disseminated in the environment, emphasizes the environmental and health problems that we face nowadays. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

First Report of Group CTX-M-9 Extended Spectrum Beta-Lactamases in Escherichia coli Isolates from Pediatric Patients in Mexico

PubMed Central

Merida-Vieyra, Jocelin; De Colsa, Agustin; Calderon Castañeda, Yair; Arzate Barbosa, Patricia; Aquino Andrade, Alejandra

2016-01-01

The aim of this study was to identify the presence of group CTX-M-9 extended spectrum beta-lactamases (ESBL) in clinical Escherichia coli isolates from pediatric patients. A total of 404 non-repeated positive ESBL E. coli isolates were collected from documented clinical infections in pediatric patients over a 2-year period. The identification and susceptibility profiles were determined using an automated system. Isolates that suggested ESBL production based on their resistance profiles to third and fourth generation cephalosporin and monobactam were selected. ESBL production was phenotypically confirmed using a diffusion method with cefotaxime and ceftazidime discs alone and in combination with clavulanic acid. blaESBL gene identification was performed through PCR amplification and sequencing. Pulsed Field Gel Electrophoresis (PFGE) and Multilocus Sequence Typing (MLST) were performed to establish the clonal relationships of the E. coli isolates. CTX-M-9-type ESBLs were detected in 2.5% of the isolates. The subtypes corresponded to blaCTX-M-14 (n = 4) and blaCTX-M-27 (n = 6). Additionally, coexistence with other beta-lactamases was observed. A clonal relationship was established in three isolates; the rest were classified as non-related. We found seven different sequence type (ST) in CTX-M-9- producing E. coli isolates. ST38 was the most frequent. This study is the first report in Mexico to document the presence of group CTX-M-9 ESBLs in E. coli isolates from pediatric patients. PMID:27992527

Molecular and epidemiological characterization of carbapenemase-producing Enterobacteriaceae in Norway, 2007 to 2014.

PubMed

Samuelsen, Ørjan; Overballe-Petersen, Søren; Bjørnholt, Jørgen Vildershøj; Brisse, Sylvain; Doumith, Michel; Woodford, Neil; Hopkins, Katie L; Aasnæs, Bettina; Haldorsen, Bjørg; Sundsfjord, Arnfinn

2017-01-01

The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) is increasing worldwide. Here we present associated patient data and molecular, epidemiological and phenotypic characteristics of all CPE isolates in Norway from 2007 to 2014 confirmed at the Norwegian National Advisory Unit on Detection of Antimicrobial Resistance. All confirmed CPE isolates were characterized pheno- and genotypically, including by whole genome sequencing (WGS). Patient data were reviewed retrospectively. In total 59 CPE isolates were identified from 53 patients. Urine was the dominant clinical sample source (37%) and only 15% of the isolates were obtained from faecal screening. The majority of cases (62%) were directly associated with travel or hospitalization abroad, but both intra-hospital transmission and one inter-hospital outbreak were observed. The number of CPE cases/year was low (2-14 cases/year), but an increasing trend was observed. Klebsiella spp. (n = 38) and E. coli (n = 14) were the dominant species and blaKPC (n = 20), blaNDM (n = 19), blaOXA-48-like (n = 12) and blaVIM (n = 7) were the dominant carbapenemase gene families. The CPE isolates were genetically diverse except for K. pneumoniae where clonal group 258 associated with blaKPC dominated. All isolates were multidrug-resistant and a significant proportion (21%) were resistant to colistin. Interestingly, all blaOXA-48-like, and a large proportion of blaNDM-positive Klebsiella spp. (89%) and E. coli (83%) isolates were susceptible in vitro to mecillinam. Thus, mecillinam could have a role in the treatment of uncomplicated urinary tract infections caused by OXA-48- or NDM-producing E. coli or K. pneumoniae. In conclusion, the impact of CPE in Norway is still limited and mainly associated with travel abroad, reflected in the diversity of clones and carbapenemase genes.

Wild Birds, Frequent Carriers of Extended-Spectrum β-Lactamase (ESBL) Producing Escherichia coli of CTX-M and SHV-12 Types.

PubMed

Alcalá, Leticia; Alonso, Carla Andrea; Simón, Carmen; González-Esteban, Chabier; Orós, Jesús; Rezusta, Antonio; Ortega, Carmelo; Torres, Carmen

2016-11-01

To get a better insight into the role of birds as reservoirs of extended-spectrum β-lactamase (ESBL) and plasmidic AmpC β-lactamase (pAmpC) Escherichia coli producers, 100 fecal samples belonging to 15 different wild avian species from Northern Spain were analyzed. Cefotaxime-resistant (CTX R ) E. coli isolates were identified in 16 of the 100 tested birds, which corresponded to 9 animal species (Gyps fulvus-griffon vulture, Larus michahellis-yellow-legged gull, Milvus migrans-black kite, Milvus milvus-red kite, Ciconia ciconia-white stork, Sturnus unicolor-spotless starling, Aquila chrysaetos-golden eagle, Cuculus canorus-common cuckoo, Tyto alba-barn owl). Fifteen isolates harbored ESBL or pAmpC-encoding genes (number of isolates): bla SHV-12 (9), bla CTX-M-1 (3), bla CTX-M-14 (2), and bla CMY-2 (1). The last CTX R isolate presented a -42-point-mutation in the chromosomal ampC promoter. Eleven out of 15 ESBL/pAmpC E. coli isolates were multiresistant (most common resistance phenotype: β-lactams-quinolones-tetracycline-sulfamethoxazole/trimethoprim). A plasmid-mediated quinolone resistance determinant (qnrS1) was identified in one E. coli from a barn owl. High genetic diversity was observed among ESBL/pAmpC E. coli isolates, with 12 different sequence types (STs), including several strains of STs frequently detected among human clinical isolates (ST38/D, ST131/B2, ST155/B1, ST10/A). The ST131 isolate belonged to the emergent ciprofloxacin-resistant H30R subclone. This study reveals a high percentage of bird as carriers of ESBL/pAmpC E. coli isolates in Spain, highlighting the elevated rate among storks, kites, and vultures. Wild birds can contribute to the global spread of ESBL/pAmpC-producing E. coli in natural ecosystems.

Alignment-Free Design of Highly Discriminatory Diagnostic Primer Sets for Escherichia coli O104:H4 Outbreak Strains

PubMed Central

Bielaszewska, Martina; Karch, Helge; Toth, Ian K.

2012-01-01

Background An Escherichia coli O104:H4 outbreak in Germany in summer 2011 caused 53 deaths, over 4000 individual infections across Europe, and considerable economic, social and political impact. This outbreak was the first in a position to exploit rapid, benchtop high-throughput sequencing (HTS) technologies and crowdsourced data analysis early in its investigation, establishing a new paradigm for rapid response to disease threats. We describe a novel strategy for design of diagnostic PCR primers that exploited this rapid draft bacterial genome sequencing to distinguish between E. coli O104:H4 outbreak isolates and other pathogenic E. coli isolates, including the historical hæmolytic uræmic syndrome (HUSEC) E. coli HUSEC041 O104:H4 strain, which possesses the same serotype as the outbreak isolates. Methodology/Principal Findings Primers were designed using a novel alignment-free strategy against eleven draft whole genome assemblies of E. coli O104:H4 German outbreak isolates from the E. coli O104:H4 Genome Analysis Crowd-Sourcing Consortium website, and a negative sequence set containing 69 E. coli chromosome and plasmid sequences from public databases. Validation in vitro against 21 ‘positive’ E. coli O104:H4 outbreak and 32 ‘negative’ non-outbreak EHEC isolates indicated that individual primer sets exhibited 100% sensitivity for outbreak isolates, with false positive rates of between 9% and 22%. A minimal combination of two primers discriminated between outbreak and non-outbreak E. coli isolates with 100% sensitivity and 100% specificity. Conclusions/Significance Draft genomes of isolates of disease outbreak bacteria enable high throughput primer design and enhanced diagnostic performance in comparison to traditional molecular assays. Future outbreak investigations will be able to harness HTS rapidly to generate draft genome sequences and diagnostic primer sets, greatly facilitating epidemiology and clinical diagnostics. We expect that high throughput primer design strategies will enable faster, more precise responses to future disease outbreaks of bacterial origin, and help to mitigate their societal impact. PMID:22496820

Prevalence of Antibiotic-Resistant Escherichia coli in Drinking Water Sources in Hangzhou City

PubMed Central

Chen, Zhaojun; Yu, Daojun; He, Songzhe; Ye, Hui; Zhang, Lei; Wen, Yanping; Zhang, Wenhui; Shu, Liping; Chen, Shuchang

2017-01-01

This study investigated the distribution of antibiotic resistant Escherichia coli (E. coli) and examined the possible relationship between water quality parameters and antibiotic resistance from two different drinking water sources (the Qiantang River and the Dongtiao Stream) in Hangzhou city of China. E. coli isolates were tested for their susceptibility to 18 antibiotics. Most of the isolates were resistant to tetracycline (TE), followed by ampicillin (AM), piperacillin (PIP), trimethoprim/sulfamethoxazole (SXT), and chloramphenicol (C). The antibiotic resistance rate of E. coli isolates from two water sources was similar; For E. coli isolates from the Qiantang River, their antibiotic resistance rates decreased from up- to downstream. Seasonally, the dry and wet season had little impact on antibiotic resistance. Spearman's rank correlation revealed significant correlation between resistance to TE and phenicols or ciprofloxacin (CIP), as well as quinolones (ciprofloxacin and levofloxacin) and cephalosporins or gentamicin (GM). Pearson's chi-square tests found certain water parameters such as nutrient concentration were strongly associated with resistance to some of the antibiotics. In addition, tet genes were detected from all 82 TE-resistant E. coli isolates, and most of the isolates (81.87%) contained multiple tet genes, which displayed 14 different combinations. Collectively, this study provided baseline data on antibiotic resistance of drinking water sources in Hangzhou city, which indicates drinking water sources could be the reservoir of antibiotic resistance, potentially presenting a public health risk. PMID:28670309

Prevalence of Antibiotic-Resistant Escherichia coli in Drinking Water Sources in Hangzhou City.

PubMed

Chen, Zhaojun; Yu, Daojun; He, Songzhe; Ye, Hui; Zhang, Lei; Wen, Yanping; Zhang, Wenhui; Shu, Liping; Chen, Shuchang

2017-01-01

This study investigated the distribution of antibiotic resistant Escherichia coli ( E. coli ) and examined the possible relationship between water quality parameters and antibiotic resistance from two different drinking water sources (the Qiantang River and the Dongtiao Stream) in Hangzhou city of China. E. coli isolates were tested for their susceptibility to 18 antibiotics. Most of the isolates were resistant to tetracycline (TE), followed by ampicillin (AM), piperacillin (PIP), trimethoprim/sulfamethoxazole (SXT), and chloramphenicol (C). The antibiotic resistance rate of E. coli isolates from two water sources was similar; For E. coli isolates from the Qiantang River, their antibiotic resistance rates decreased from up- to downstream. Seasonally, the dry and wet season had little impact on antibiotic resistance. Spearman's rank correlation revealed significant correlation between resistance to TE and phenicols or ciprofloxacin (CIP), as well as quinolones (ciprofloxacin and levofloxacin) and cephalosporins or gentamicin (GM). Pearson's chi-square tests found certain water parameters such as nutrient concentration were strongly associated with resistance to some of the antibiotics. In addition, tet genes were detected from all 82 TE-resistant E. coli isolates, and most of the isolates (81.87%) contained multiple tet genes, which displayed 14 different combinations. Collectively, this study provided baseline data on antibiotic resistance of drinking water sources in Hangzhou city, which indicates drinking water sources could be the reservoir of antibiotic resistance, potentially presenting a public health risk.

Antibiotic Resistance, RAPD- PCR Typing of Multiple Drug Resistant Strains of Escherichia Coli From Urinary Tract Infection (UTI).

PubMed

Marialouis, Xavier Alexander; Santhanam, Amutha

2016-03-01

Global spreading of multidrug resistant strains of Escherichia coli is responsible for Urinary Tract Infection (UTI) which is a major health problem in of concern. Among the gram negative bacteria, the major contributors for UTI belongs to the family Enterobacteriaceae, which includes E. coli, Klebsiella, Citrobacter and Proteus. However, E. coli accounts for the major cause of Urinary tract infections (UTIs) and accounts for 75% to 90% of UTI isolates. The main aim of this study is to analyse the phylogenetic grouping of clinical isolates of UTI E. coli. In this study nearly 58 E. coli strains were isolated and confirmed through microbiological, biochemical characterization. The urine samples were collected from outpatients having symptoms of UTI, irrespective of age and sex in Tamil Nadu, India. The isolates were subjected to analyse for ESBL and AmpC β-lactamase production. To understand its genetic correlation, molecular typing was carried out using RAPD-PCR method. Here we noted phenotypically twenty seven isolates were positive for ESBL and seven for AmpC β-lactamase production. However, among the ESBL isolates higher sensitivity was noted for Nitrofurantoin and Cefoxitin. It is worth to note that the prevalence of UTIs was more common among female and elderly male. Phylogenetic grouping revealed the presence of 24 isolates belonged to B2 group followed by 19 isolates to group A, eight isolates to group B1 and Seven isolates to group D. Phenotypically most of the strains were positive for ESBL and showed high sensitivity for Nitrofurantoin and cefoxitin.

Prevalence of O25b-ST131 clone among Escherichia coli strains producing CTX-M-15, CTX-M-14 and CTX-M-92 β-lactamases.

PubMed

Giedraitienė, Agnė; Vitkauskienė, Astra; Pavilonis, Alvydas; Patamsytė, Vaiva; Genel, Nathalie; Decre, Dominique; Arlet, Guillaume

2017-02-01

Dissemination of multidrug-resistant Escherichia coli is closely associated with the worldwide spread of a single clone ST131, which is the main cause of urinary tract and bloodstream infections in patients from nursing homes and immunocompromised patients. The aim of our study was to determine the prevalence of ST131 clone and the replicons involved in the spread of bla CTX-M genes among O25b-ST131 CTX-M-producing E. coli isolates in Lithuania. The strains included in this study were screened for CTX-M β-lactamase-encoding genes, phylogenetic groups and ST131 clone by PCR. Bacterial conjugation was performed to identify plasmid replicon types responsible for bla CTX-M genes dissemination. A total of 158 E. coli clinical non-duplicate ESBL isolates were analyzed. Nearly half (n = 67, 42.4%) of the investigated E. coli isolates belonged to phylogenetic group B2. The isolates producing CTX-M-92 β-lactamases were identified to be the ST131 clone more frequently than the non-ST131 clone (11.5% vs. 3.1%, p = .035). The CTX-M-15 isolates were identified as ST131 isolates less frequently than non-ST131 isolates (50.8% vs. 71.1%; p = .015). The ST131 clone isolates contained type L/M and A/C replicons; a fused FII/FIB replicon was found in four isolates (23.5%). Type HI1 replicon was identified in ST131 E. coli isolates producing CTX-M-15 β-lactamases. This study demonstrates the predominance of the ST131 clone among CTX-M β-lactamase-producing E. coli isolates. Dissemination of bla CTX-M genes in ST131 strains can be linked not only to highly adapted IncF plasmids such as FII/FIB and FII, but also to plasmid replicon types A/C, L/M and HI1.

Characterisation of STEC and other diarrheic E. coli isolated on CHROMagar™STEC at a tertiary referral hospital, Cape Town.

PubMed

Kalule, John Bosco; Keddy, Karen H; Nicol, Mark P

2018-06-08

Shiga toxin producing E. coli (STEC) is an emerging zoonotic pathogen that can cause acute renal failure, especially in children. Clinical microbiology laboratories may fail to detect STEC and other diarrhoeic E. coli unless purposive rigorous screening procedures are followed using appropriate diagnostic technology; CHROMagar™STEC has rarely been used for isolation of African diarrhoeic E. coli hence characteristics of isolates on this medium are not yet fully understood. This study aimed to determine the prevalence and characteristics of STEC and other diarrhoeic E. coli isolated on CHROMagar™STEC from stool samples submitted to the microbiology laboratory of a South African public sector tertiary care hospital. In total, 733 stool samples were tested. Of these, 4.5% (33/733) possessed diarrhoeic E. coli. Of the diarrheic E. coli, 5/33 (15.2%) were STEC, 15/33 (45.5%) EAggEC, 6/33 (18.2%) atypical EPEC, 5/33 (15.2%) typical EPEC, and 1/33 (3%) DAEC. None of the STEC isolates had been identified by routine testing (based on using sorbitol media to test for E. coli O157: H7 strains and not the other STEC) in the laboratory. Of the 33 strains, 55% (95% CI = 40.8-72.7) showed resistance to ampicillin. CHROMagar™STEC enabled detection of tellurite - resistant diarrhoeic E. coli that would be missed using routine methods. Further studies are needed to determine the proportion and characteristics of those which might have been missed using this approach.

Extended-spectrum-β-lactamase-producing Escherichia coli as a cause of pediatric infections: report of a neonatal intensive care unit outbreak due to a CTX-M-14-producing strain.

PubMed

Oteo, Jesús; Cercenado, Emilia; Fernández-Romero, Sara; Saéz, David; Padilla, Belén; Zamora, Elena; Cuevas, Oscar; Bautista, Verónica; Campos, José

2012-01-01

Little information is available about pediatric infections caused by extended-spectrum-β-lactamase (ESBL)-producing Escherichia coli. We characterized an outbreak caused by a CTX-M-14-producing E. coli isolate in a neonatal intensive care unit (NICU) and studied other infections caused by ESBL-producing E. coli in non-NICU pediatric units. All children ≤4 years old who were infected or colonized by ESBL-producing E. coli isolates between January 2009 and September 2010 were included. Molecular epidemiology was studied by phylogroup analysis, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing. Antibiotic resistance genes were analyzed by PCR and sequencing. Plasmids were studied by PFGE with S1 nuclease digestion and by incompatibility group analysis using a PCR-based replicon-typing scheme. Of the ESBL-producing E. coli isolates colonizing or infecting the 30 newborns, identical PFGE results were observed for 21 (70%) isolates, which were classified as CTX-M-14-producing E. coli of ST23 phylogroup A. bla(CTX-M-14a) was linked to ISEcp1 and was carried on an ∼80-bp IncK plasmid. A smaller ongoing outbreak due to SHV-12-producing ST131 E. coli was also identified in the same NICU. Fifteen additional infections with ESBL-producing E. coli were identified in non-NICU pediatric units, but none was caused by the CTX-M-14-producing E. coli epidemic clone. Overall, CTX-M-14 (71.1%), CTX-M-15 (13.3%), and SHV-12 (13.3%) were the most important ESBLs causing pediatric infections in this study. Infections of newborns with CTX-M-14-producing E. coli were caused by both clonal and nonclonal isolates.

Degenerate primer MOB typing of multiresistant clinical isolates of E. coli uncovers new plasmid backbones.

PubMed

Garcillán-Barcia, M Pilar; Ruiz del Castillo, Belén; Alvarado, Andrés; de la Cruz, Fernando; Martínez-Martínez, Luis

2015-01-01

Degenerate Primer MOB Typing is a PCR-based protocol for the classification of γ-proteobacterial transmissible plasmids in five phylogenetic relaxase MOB families. It was applied to a multiresistant E. coli collection, previously characterized by PCR-based replicon-typing, in order to compare both methods. Plasmids from 32 clinical isolates of multiresistant E. coli (19 extended spectrum beta-lactamase producers and 13 non producers) and their transconjugants were analyzed. A total of 95 relaxases were detected, at least one per isolate, underscoring the high potential of these strains for antibiotic-resistance transmission. MOBP12 and MOBF12 plasmids were the most abundant. Most MOB subfamilies detected were present in both subsets of the collection, indicating a shared mobilome among multiresistant E. coli. The plasmid profile obtained by both methods was compared, which provided useful data upon which decisions related to the implementation of detection methods in the clinic could be based. The phylogenetic depth at which replicon and MOB-typing classify plasmids is different. While replicon-typing aims at plasmid replication regions with non-degenerate primers, MOB-typing classifies plasmids into relaxase subfamilies using degenerate primers. As a result, MOB-typing provides a deeper phylogenetic depth than replicon-typing and new plasmid groups are uncovered. Significantly, MOB typing identified 17 plasmids and an integrative and conjugative element, which were not detected by replicon-typing. Four of these backbones were different from previously reported elements. Copyright © 2014 Elsevier Inc. All rights reserved.

Genome analysis of E. coli isolated from Crohn's disease patients.

PubMed

Rakitina, Daria V; Manolov, Alexander I; Kanygina, Alexandra V; Garushyants, Sofya K; Baikova, Julia P; Alexeev, Dmitry G; Ladygina, Valentina G; Kostryukova, Elena S; Larin, Andrei K; Semashko, Tatiana A; Karpova, Irina Y; Babenko, Vladislav V; Ismagilova, Ruzilya K; Malanin, Sergei Y; Gelfand, Mikhail S; Ilina, Elena N; Gorodnichev, Roman B; Lisitsyna, Eugenia S; Aleshkin, Gennady I; Scherbakov, Petr L; Khalif, Igor L; Shapina, Marina V; Maev, Igor V; Andreev, Dmitry N; Govorun, Vadim M

2017-07-19

Escherichia coli (E. coli) has been increasingly implicated in the pathogenesis of Crohn's disease (CD). The phylogeny of E. coli isolated from Crohn's disease patients (CDEC) was controversial, and while genotyping results suggested heterogeneity, the sequenced strains of E. coli from CD patients were closely related. We performed the shotgun genome sequencing of 28 E. coli isolates from ten CD patients and compared genomes from these isolates with already published genomes of CD strains and other pathogenic and non-pathogenic strains. CDEC was shown to belong to A, B1, B2 and D phylogenetic groups. The plasmid and several operons from the reference CD-associated E. coli strain LF82 were demonstrated to be more often present in CDEC genomes belonging to different phylogenetic groups than in genomes of commensal strains. The operons include carbon-source induced invasion GimA island, prophage I, iron uptake operons I and II, capsular assembly pathogenetic island IV and propanediol and galactitol utilization operons. Our findings suggest that CDEC are phylogenetically diverse. However, some strains isolated from independent sources possess highly similar chromosome or plasmids. Though no CD-specific genes or functional domains were present in all CD-associated strains, some genes and operons are more often found in the genomes of CDEC than in commensal E. coli. They are principally linked to gut colonization and utilization of propanediol and other sugar alcohols.

Novel approach for differentiating Shigella species and Escherichia coli by matrix-assisted laser desorption ionization-time of flight mass spectrometry.

PubMed

Khot, Prasanna D; Fisher, Mark A

2013-11-01

Shigella species are so closely related to Escherichia coli that routine matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) cannot reliably differentiate them. Biochemical and serological methods are typically used to distinguish these species; however, "inactive" isolates of E. coli are biochemically very similar to Shigella species and thus pose a greater diagnostic challenge. We used ClinProTools (Bruker Daltonics) software to discover MALDI-TOF MS biomarker peaks and to generate classification models based on the genetic algorithm to differentiate between Shigella species and E. coli. Sixty-six Shigella spp. and 72 E. coli isolates were used to generate and test classification models, and the optimal models contained 15 biomarker peaks for genus-level classification and 12 peaks for species-level classification. We were able to identify 90% of E. coli and Shigella clinical isolates correctly to the species level. Only 3% of tested isolates were misidentified. This novel MALDI-TOF MS approach allows laboratories to streamline the identification of E. coli and Shigella species.

Plasmid Replicon Typing of Commensal and Pathogenic Escherichia coli Isolates▿

PubMed Central

Johnson, Timothy J.; Wannemuehler, Yvonne M.; Johnson, Sara J.; Logue, Catherine M.; White, David G.; Doetkott, Curt; Nolan, Lisa K.

2007-01-01

Despite the critical role of plasmids in horizontal gene transfer, few studies have characterized plasmid relatedness among different bacterial populations. Recently, a multiplex PCR replicon typing protocol was developed for classification of plasmids occurring in members of the Enterobacteriaceae. Here, a simplified version of this replicon typing procedure which requires only three multiplex panels to identify 18 plasmid replicons is described. This method was used to screen 1,015 Escherichia coli isolates of avian, human, and poultry meat origin for plasmid replicon types. Additionally, the isolates were assessed for their content of several colicin-associated genes. Overall, a high degree of plasmid variability was observed, with 221 different profiles occurring among the 1,015 isolates examined. IncFIB plasmids were the most common type identified, regardless of the source type of E. coli. IncFIB plasmids occurred significantly more often in avian pathogenic E. coli (APEC) and retail poultry E. coli (RPEC) than in uropathogenic E. coli (UPEC) and avian and human fecal commensal E. coli isolates (AFEC and HFEC, respectively). APEC and RPEC were also significantly more likely than UPEC, HFEC, and AFEC to possess the colicin-associated genes cvaC, cbi, and/or cma in conjunction with one or more plasmid replicons. The results suggest that E. coli isolates contaminating retail poultry are notably similar to APEC with regard to plasmid profiles, with both generally containing multiple plasmid replicon types in conjunction with colicin-related genes. In contrast, UPEC and human and avian commensal E. coli isolates generally lack the plasmid replicons and colicin-related genes seen in APEC and RPEC, suggesting limited dissemination of such plasmids among these bacterial populations. PMID:17277222

[In vitro antibacterial activity of Curcuma longa (Zingiberaceae) against nosocomial bacteria in Montería, Colombia].

PubMed

Méndez Álvarez, Nelson; Angulo Ortíz, Alberto; Contreras Martínez, Orfa

2016-09-01

Bacterial resistance is a growing health problem worldwide that has serious economic and social impacts, compromising public health, and the therapeutic action of current antibiotics. Therefore, the search for new compounds with antimicrobial properties is relevant in modern studies, particularly against bacteria of clinical interest. In the present study, in vitro antibacterial activity of the ethanol extract and essential oil of Curcuma longa (Zingiberaceae) was evaluated against nosocomial bacteria, using the microdilution method. Escherichia coli strains, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus sp. were used, Salmonella sp. and Bacillus sp., isolated from nosocomial infections in a hospital in the city of Monteria and reference strains of S. aureus ATCC 43300, S. aureus ATCC 29213, S. aureus ATCC 25923, P. aeruginosa ATCC 27853, E. coli ATCC 25922 and K. pneumonia ATCC 700603. The ethanol extract antibacterial profile was more efficient at higher concentrations (1 000 ppm), obtaining significant percentages of reduction of more than 50 % against K. pneumoniae ATCC 700603 and a clinical isolate of E. coli; while compared to Bacillus clinical isolate, was more active than the essential oil. For the rest of microorganisms, the reduction percentages obtained at a concentration of 1 000 ppm varied between 17 and 42 % with ethanolic extract, and 8 to 43 % with essential oil. At concentrations of 100 and 500 ppm antibacterial activity of the extracts was lower. The results indicated that the ethanolic extract and essential oil of C. longa rhizomes have active compounds with antibacterial properties that could be used in future research as a therapeutic alternative for the treatment of infections caused by nosocomial pathogens.

Characterization of antimicrobial resistant Escherichia coli isolated from processed bison carcasses.

PubMed

Li, Q; Sherwood, J S; Logue, C M

2007-12-01

To determine the phenotypic and genotypic antimicrobial susceptibility profiles of Escherichia coli from bison carcasses. The antimicrobial resistance of 138 E. coli isolates recovered from processed bison carcasses was determined by using the National Antimicrobial Resistance Monitoring System panels, polymerase chain reaction assays, plasmid analysis and conjugation studies. Resistance to 14 of the 16 antimicrobials was observed. Twenty-three (16.7%) isolates displayed resistance to at least one antimicrobial agent. The most prevalent resistances were to tetracycline (13.0%), sulfamethoxazole (7.9%) and streptomycin (5.8%). No resistance was observed to amikacin and ciprofloxacin. Further analysis of 23 antimicrobial-resistant E. coli isolates showed the presence of resistance genes corresponding to their phenotypic profiles. Results of conjugation studies carried out showed most isolates tested were able to transfer their resistance to recipients. This study indicated that multidrug-resistant E. coli isolates are present in bison. However, the resistance rate is lower than that reported in other meat species. The beneficial effects of antimicrobial-free feeding practice in bison may be promoting a reduction in the prevalence of antimicrobial resistance in commensal flora of bison.

ISOLATION AND MOLECULAR IDENTIFICATION OF POTENTIALLY PATHOGENIC Escherichia coli AND Campylobacter jejuni IN FERAL PIGEONS FROM AN URBAN AREA IN THE CITY OF LIMA, PERU

PubMed Central

CABALLERO, Moisés; RIVERA, Isabel; JARA, Luis M.; ULLOA-STANOJLOVIC, Francisco M.; SHIVA, Carlos

2015-01-01

SUMMARY Feral pigeons (Columbia livia) live in close contact with humans and other animals. They can transmit potentially pathogenic and zoonotic agents. The objective of this study was to isolate and detect strains of diarrheagenic Escherichia coli and Campylobacter jejuni of urban feral pigeons from an area of Lima, Peru. Fresh dropping samples from urban parks were collected for microbiological isolation of E. coli strains in selective agar, and Campylobacter by filtration method. Molecular identification of diarrheagenic pathotypes of E.coli and Campylobacter jejuni was performed by PCR. Twenty-two parks were sampled and 16 colonies of Campylobacter spp. were isolated. The 100% of isolates were identified as Campylobacter jejuni. Furthermore, 102 colonies of E. coliwere isolated and the 5.88% resulted as Enteropathogenic (EPEC) type and 0.98% as Shiga toxin-producing E. coli (STEC). The urban feral pigeons of Lima in Peru can act as a reservoir or carriers of zoonotic potentially pathogenic enteric agents. PMID:26603225

Dynamic changes in the population structure of Escherichia coli in the Yeongsan River basin of South Korea.

PubMed

Jang, Jeonghwan; Di, Doris Y W; Han, Dukki; Unno, Tatsuya; Lee, Jeom-Ho; Sadowsky, Michael J; Hur, Hor-Gil

2015-11-01

Although Escherichia coli has been used as an indicator to examine fecal contamination of aquatic environment, it also has been reported to become naturalized to secondary habitats, including soil, water and beach sand. A total of 2880 E. coli isolates obtained from surface water and sediment samples from the Yeongsan River in 2013 were genotyped by using the horizontal fluorophore-enhanced rep-PCR DNA fingerprinting technique. Although different E. coli genotypic groups were observed between surface water and sediments in the dry season, they were mingled and undifferentiated from each other in the rainy season. This indicates that there are frequent sediment resuspension events in the river basin. Moreover, the genotypic composition of the E. coli population in the Yeongsan River basin changes over months and years, implying that genotypic structure of E. coli populations dynamically fluctuates in the river environment. Consequently, our data suggests that the use of E. coli libraries for fecal source tracking needs to be reassessed to account for the changing structure of riverine E. coli populations. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The species accuracy of the Most Probable Number (MPN) European Union reference method for enumeration of Escherichia coli in marine bivalves.

PubMed

Grevskott, Didrik Hjertaker; Svanevik, Cecilie Smith; Wester, Astrid Louise; Lunestad, Bjørn Tore

2016-12-01

Continuous European Union programmes with specified methods for enumeration of Escherichia coli in bivalves for human consumption are currently running. The objective of this research was to examine the species accuracy of the five times three tube Most Probable Number (MPN) EU reference method used for detection of E. coli in marine bivalves. Among 549 samples of bivalves harvested from Norwegian localities during 2014 and 2015, a total number of 200 bacterial isolates were prepared from randomly selected culture-positive bivalves. These presumptive E. coli isolates were characterized biochemically by the Analytical Profile Index (API) 20E, as well as by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS). The majority of isolates (90%) were identified as E. coli, by both API 20E and MALDI-TOF MS. Ten isolates (5%) were identified as Klebsiella pneumoniae, while one isolate was identified as K. oxytoca by both methods, whereas three isolates were identified as Acinetobacter baumannii, Citrobacter braakii, and Enterobacter cloacae, respectively. The identification of the remaining six isolates were not in compliance between the two methods. Copyright © 2016 Elsevier B.V. All rights reserved.

Antibiotic resistance among Escherichia coli isolates from stool samples of children aged 3 to 14 years from Ujjain, India

PubMed Central

2013-01-01

Background Antibiotic resistance is a major global public health concern, particularly in settings where few treatment options are available. Limited research has been done on antibiotic resistance in Escherichia coli of Indian children at community level. Therefore we studied antibiotic resistance patterns in E. coli isolates from stool samples of children aged 3-14 years from Ujjain, Central India, to investigate associations of resistance with demographic variables. Methods Children, 3-14 years of age, were included from 30 randomly selected villages of Palwa demographic surveillance site, Ujjain, India. Parents were interviewed using a questionnaire, and stool samples were collected from participating children. E. coli were isolated from stool samples (n = 529), and susceptibility testing to 18 different antibiotics was done using standard methods. Results The proportions of isolates resistant to various antibiotics were, nalidixic acid, (45%), tetracycline (37%), ampicillin (37%), sulfamethoxazole/trimethoprim (29%) and amoxicillin/clavulanic acid (29%). No isolates were resistant to imipenem. Overall, 72% of isolates were resistant to at least one antibiotic and 33% were multi-drug resistant. High rates of cross-resistance were seen for 15 (83%) of the antibiotics studied. E. coli isolates from children with literate mothers were more resistant to penicillins and fluoroquinolones. ESBL-producers comprised 9% of the isolates. Conclusion Antibiotic resistance and cross-resistance were common in E. coli from stools of children. Resistance rates were associated with maternal literacy. PMID:24124728

Dissemination of ST131 and ST393 community-onset, ciprofloxacin-resistant Escherichia coli clones causing urinary tract infections in Korea.

PubMed

Lee, Mi Young; Choi, Hyeon Jin; Choi, Ji Young; Song, Minsuk; Song, Yoosuk; Kim, Shin-Woo; Chang, Hyun-Ha; Jung, Sook-In; Kim, Yeon-Sook; Ki, Hyun Kyun; Son, Jun Seong; Kwon, Ki Tae; Heo, Sang Taek; Yeom, Joon-Sup; Shin, Sang Yop; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon; Ko, Kwan Soo

2010-02-01

Ciprofloxacin-resistant Escherichia coli is growing concern in clinical settings. In this study, we investigated the distribution of virulence determinants and phylogenetic groups among community-onset, ciprofloxacin-resistant E. coli isolates causing urinary tract infections (UTIs) in Korea. In addition, the evidence of clonal spread in the community was also examined. From November 2006 to August 2007, 543 community-onset E. coli isolates causing UTIs were collected as part of a multicenter surveillance study. In vitro susceptibility testing was performed using broth microdilution method. Distribution of virulence determinants and phylogenetic groupings were examined. In addition, multilocus sequence typing (MLST) analysis was performed. In vitro antimicrobial susceptibility testing revealed that 154 isolates (28.4%) were ciprofloxacin-resistant. Of these, 129 ciprofloxacin-resistant E. coli isolates were further characterized. As a result of phylogenetic subgrouping, we found that phylogenetic subgroup D was the most predominant (46 isolates, 35.7%), followed by B2 (44 isolates, 34.1%), A (21 isolates, 16.3%), and B1 (18 isolates, 14.0%). MLST analysis showed 48 sequence types (STs). The most prevalent ST was ST131 (32 isolates, 24.8%), followed by ST393 (23 isolates, 17.8%). While all ST131 isolates belonged to phylogenetic subgroup B2, which is known to be a highly virulent, all ST393 isolates belonged to subgroup D. ST131 and ST393 showed different profiles of virulence factors; papA, papG allele III, and traT genes were significantly more prevalent in ST131 than in ST393 (p values, <0.001). Based on genotyping, it is suggested that epidemic and virulent ciprofloxacin-resistant E. coli clones such as ST131 and ST393 have disseminated in Korea. However, the diversity of CTX-M genes in ST131 isolates may indicate that ESBL genes have been acquired independently or several ESBL-producing, ciprofloxacin-resistant E. coli clones may have disseminated in the Korean community. Copyright 2009 The British Infection Society. Published by Elsevier Ltd. All rights reserved.

First Report of Prevalence of CTX-M-15-Producing Escherichia coli O25b/ST131 from Iran.

PubMed

Namaei, Mohammad Hasan; Yousefi, Masoud; Ziaee, Masoud; Salehabadi, Alireza; Ghannadkafi, Malaknaz; Amini, Elham; Askari, Parvin

2017-10-01

The emergence of Escherichia coli sequence type 131 (ST131) as a multidrug-resistant and virulent pathogen represents a major challenge to public health globally. Recently, the O25b/ST131 E. coli producing CTX-M-15 with high virulence potential has been reported worldwide, but has received little attention in Iran. This study is the first in Iran to specifically determine the spread of the O25b/ST131 clone producing CTX-M-15 among E. coli isolates belonging to the B2 phylogenetic group. ST131 clone in phylogenetic group B2 was detected based on PCR detection of ST131-specific single-nucleotide polymorphisms in mdh and gyrB. O25b/ST131 E. coli clone was confirmed utilizing O25b/ST131 clone allele-specific PCR for the pabB gene. All group B2 E. coli isolates were characterized based on antibiotic susceptibility, extended-spectrum β-lactamase (ESBL) enzymes, and virulence traits. Our results demonstrated that 38 out of the 154 B2 group isolates (24.7%) were identified as belonging to the ST131 clone. Furthermore, of these, 28 isolates (73.6%) were detected as O25b/ST131 clone. Antibiotic resistance of ST131 E. coli isolates to ciprofloxacin, gentamicin, cefotaxime, and aztreonam was significantly higher than non-ST131 isolates. Almost all of the O25b/ST131 isolates with the ability for ESBL production were reported as CTX-M-15 producing (95.5%). Our results showed that the most prevalent virulence trait in ST131 clone was ompT (94.7%). This study is the first to report the prevalence of the CTX-M-15-producing O25b/ST131 E. coli in Iran. Our findings reinforce the surveillance of dissemination of ST131 E. coli clone as a major drug-resistant pathogen and an important new public health threat.

Predominance of the ac variant in K88-positive Escherichia coli isolates from swine.

PubMed Central

Westerman, R B; Mills, K W; Phillips, R M; Fortner, G W; Greenwood, J M

1988-01-01

Monoclonal antibodies to K88ac and K88ab were used in enzyme-linked immunosorbent assays on Escherichia coli cultures known to produce K88 pili. A total of 415 K88-positive E. coli isolates from nine states were all found to be the K88ac variant. The cultures tested were isolated during the years 1976 to 1985. PMID:3277990

Draft Genome Sequences of Five Neonatal Meningitis-Causing Escherichia coli Isolates (SP-4, SP-5, SP-13, SP-46, and SP-65)

PubMed Central

Xu, Aixia; Johnson, James R.; Sheen, Shiowshuh

2018-01-01

ABSTRACT Neonatal meningitis-causing Escherichia coli isolates (SP-4, SP-5, SP-13, SP-46, and SP-65) were recovered between 1989 and 1997 from infants in the Netherlands. Here, we report the draft genome sequences of these five E. coli isolates, which are currently being used to validate food safety processing technologies. PMID:29674529

Draft genome sequences of six neonatal meningitis-causing escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65)

USDA-ARS?s Scientific Manuscript database

Neonatal meningitis Escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65) were recovered from infants in the Netherlands from 1989 to 1997. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used to validate food safety processing te...

Escherichia coli ST131, an Intriguing Clonal Group

PubMed Central

Bertrand, Xavier; Madec, Jean-Yves

2014-01-01

SUMMARY In 2008, a previously unknown Escherichia coli clonal group, sequence type 131 (ST131), was identified on three continents. Today, ST131 is the predominant E. coli lineage among extraintestinal pathogenic E. coli (ExPEC) isolates worldwide. Retrospective studies have suggested that it may originally have risen to prominence as early as 2003. Unlike other classical group B2 ExPEC isolates, ST131 isolates are commonly reported to produce extended-spectrum β-lactamases, such as CTX-M-15, and almost all are resistant to fluoroquinolones. Moreover, ST131 E. coli isolates are considered to be truly pathogenic, due to the spectrum of infections they cause in both community and hospital settings and the large number of virulence-associated genes they contain. ST131 isolates therefore seem to contradict the widely held view that high levels of antimicrobial resistance are necessarily associated with a fitness cost leading to a decrease in pathogenesis. Six years after the first description of E. coli ST131, this review outlines the principal traits of ST131 clonal group isolates, based on the growing body of published data, and highlights what is currently known and what we need to find out to provide public health authorities with better information to help combat ST131. PMID:24982321

Extended-spectrum β-lactamase producing Escherichia coli in hospital wastewaters and sewage treatment plants in Queensland, Australia.

PubMed

Gündoğdu, Aycan; Jennison, Amy V; Smith, Helen V; Stratton, Helen; Katouli, Mohammad

2013-11-01

We investigated the prevalence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in untreated hospital wastewaters and 2 sewage treatment plants (STPs). A collection of 252 ESBL-producing E. coli isolates from hospital wastewater and STPs were typed and tested for resistance to 17 antimicrobial agents and for the presence of integron-associated integrases (intI gene) and ESBL genes. Eighty-nine percent (n = 176) of the ESBL-producing E. coli strains from hospital wastewater were found in more than 1 sample (common types), with 1 common type accounting for 35% of isolates, found in all samples. These strains were also resistant to up to 9 non-β-lactam antibiotics and showed the same pattern of resistance in all samples. More than 73% of the hospital wastewater isolates possessed SHV-type ESBL as opposed to isolates from STPs that carried only CTX-M-type ESBL genes. The prevalence of the intI gene did not differ between the sources of the isolates. Certain ESBL-producing E. coli were dominant in hospital wastewaters. These strains possessed β-lactamase genes that were different from isolates found in STPs. From a public health point of view, the presence of such a high level of ESBL-producing E. coli strains in hospital wastewaters is of great importance.

Emergence of carbapenem resistant Escherichia coli isolates producing blaNDM and blaOXA-48-like carried on IncA/C and IncL/M plasmids at two Iranian university hospitals.

PubMed

Solgi, Hamid; Giske, Christian G; Badmasti, Farzad; Aghamohammad, Shadi; Havaei, Seyed Asghar; Sabeti, Shahram; Mostafavizadeh, Kamyar; Shahcheraghi, Fereshteh

2017-11-01

The emergence of carbapenem resistance among Escherichia coli is a serious threat to public health. The objective of this study was to investigate resistance genes and clonality of carbapenem resistant E. coli in Iran. Between February 2015 and July 2016, a total of 32 non-duplicate E. coli isolates that were ertapenem resistant or intermediate (R/I-ETP) were collected from patient clinical or surveillance cultures (rectal swabs) at two university hospitals. Resistance genes were identified by PCR and sequencing. Conjugation experiments, PCR-based replicon typing, PFGE and multilocus sequence typing (MLST) were performed. PCR assays showed, among the 32 isolates, twenty-nine strains produced carbapenemase genes. The predominant carbapenemase was bla OXA-48 (82.8%), followed by bla NDM-1 (31%), bla NDM-7 (6.9%) and bla OXA-181 (3.4%). Seven of the bla NDM positive isolates co-harbored bla OXA-48 carbapenemases. The bla NDM and bla OXA-48 were found in IncA/C and IncL/M conjugative plasmids, respectively. The bla CTX-M-15 , qnrA and intI1 genes were also present in most isolates. The PFGE revealed genetic diversity among the 28 E. coli isolates, which belonged to six minor PFGE clusters and 14 isolates were singletons. The 26 isolates were distributed into 18 STs, of which two were dominant (ST648 and ST167). We identified one bla NDM-1 -positive ST131 E. coli isolates that harbor the bla CTX-M-15 and bla TEM genes. Horizontal transfer of IncA/C and IncL/M plasmids has likely facilitated the spread of the bla OXA-48 and bla NDM genes among E. coli. Their clonal diversity and the presence of faecal carriers in isolates suggest an endemic spread of OXA-48 and NDM. Therefore, it emphasizes the critical importance of monitoring and controlling the spread of carbapenem resistant E. coli. Copyright © 2017. Published by Elsevier B.V.

Simultaneous gut colonisation and infection by ESBL-producing Escherichia coli in hospitalised patients.

PubMed

Asir, Johny; Nair, Shashikala; Devi, Sheela; Prashanth, Kenchappa; Saranathan, Rajagopalan; Kanungo, Reba

2015-01-01

Extended spectrum betalactamase (ESBL)-producing organisms are a major cause of hospital-acquired infections. ESBL-producing Escherichia coli (E. coli) have been recovered from the hospital environment. These drug-resistant organisms have also been found to be present in humans as commensals. The present investigation intended to isolate ESBL-producing E. coli from the gut of already infected patients; to date, only a few studies have shown evidence of the gut microflora as a major source of infection. This study aimed to detect the presence of ESBL genes in E.coli that are isolated from the gut of patients who have already been infected with the same organism. A total of 70 non-repetitive faecal samples were collected from in-patients of our hospital. These in-patients were clinically diagnosed and were culture-positive for ESBL-producing E. coli either from blood, urine, or pus. Standard microbiological methods were used to detect ESBL from clinical and gut isolates. Genes coding for major betalactamase enzymes such as bla CTX-M , bla TEM, and bla SHV were investigated by polymerase chain reaction (PCR). ESBL-producing E. coli was isolated from 15 (21 per cent) faecal samples of the 70 samples that were cultured. PCR revealed that out of these 15 isolates, the bla CTX-M gene was found in 13 (86.6 per cent) isolates, the bla TEM was present in 11 (73.3 per cent) isolates, and bla SHV only in eight (53.3 per cent) isolates. All 15 clinical and gut isolates had similar phenotypic characters and eight of the 15 patients had similar pattern of genes (bla TEM, bla CTX-M, and bla SHV) in their clinical and gut isolates. Strains with multiple betalactamase genes that colonise the gut of hospitalised patients are a potential threat and it may be a potential source of infection.

An evaluation of E. coli in urinary tract infection in emergency department at KAMC in Riyadh, Saudi Arabia: retrospective study.

PubMed

Alanazi, Menyfah Q; Alqahtani, Fulwah Y; Aleanizy, Fadilah S

2018-02-09

Urinary tract infection (UTIS) is a common infectious disease in which level of antimicrobial resistance are alarming worldwide. Therefore, this study aims to describe the prevalence and the resistance pattern of the main bacteria responsible for UTIS Escherichia coli (E. coli). Retrospective chart review for patients admitted to emergency department and diagnosed with UTIS at KAMC, in Riyadh, Saudi Arabia between January to March 2008 was performed. Antimicrobial susceptibility to ampicillin, augmentin (amoxicillin/clavulanate), cefazolin, co-trimoxazole (sulfamethoxazole/trimethoprim), ciprofloxacin, and nitrofurantoin, and cefpodoxime was determined for 101 E. coli urinary isolates. Escherichia coli was the most prevalent pathogen contributing to UTIS representing 93.55, 60.24, and 45.83% of all pathogen isolated from urine culture of pediatric, adult, and elderly, respectively. High rates of resistance to ampicillin (82.76, 58, and 63.64%) and co-trimoxazole (51.72, 42, and 59.09%), among E. coli isolated from pediatric, adult and elderly respectively. Nitrofurantoin was the most active agent, followed by ciprofloxacin, augmentin and cefazolin. 22.77% of E. coli isolates exhibited multiple drug resistance (MDR). Among 66 and 49 isolates resistant to ampicillin and co-trimoxazole, respectively, 34.84 and 42.85% were MDR. In contrast, all isolates resistant to augmentin and nitrofurantoin were MRD, while 72.7 and 82.4% of isolates resistant to ciprofloxacin and cefazolin were MDR. High resistance was observed to ampicillin and co-trimoxazole which commonly used as empirical treatments for UTIS, limiting their clinical use. This necessitates continuous surveillance for resistance pattern of uropathogens against antibiotics.

Resistance patterns of diversified phylogroups of Escherichia coli associated with mothers having history of preterm births in Pakistan.

PubMed

Rana, Fiza; Siddiqui, Sidra; Khan, Ayesha; Siddiqui, Fariha; Noreen, Zobia; Bokhari, Sadia; Bokhari, Habib

2017-01-01

Urinary tract infections (UTIs) are caused by extraintestinal pathogenic Escherichia coli (ExPEC), and are one of the key predictors of preterm births. In the light of this fact, present study was conducted to determine the predominant Escherichia coli (E. coli) phylotypes and their associated antibiotic susceptibility patterns, isolated from pregnant mothers with the history of preterm births. Forty seven E. coli strains were isolated out of a total of 80 urine samples of pregnant women. The isolates were phylotyped and further screened for the presence of Clonal group A. Moreover, Antimicrobial susceptibility testing and screening for Extended Spectrum Beta Lactamase (ESBL) producing strains were also performed. Among the 47 isolates, phylogroup B2 was found to be highly prevalent (45%), followed by group D (23%), B1 (10.64%), A (6.38%), E (6.38%), cryptic clade I (4.25%) and F (2.13%). Two isolates belonged to CgA and 41 (87.23%) isolates were found to be multidrug-resistant. Out of nine antibiotics tested in the study, the isolates displayed high resistance to Ampicillin (82.6%), Sulphamethoxazole (65.22%), Nalidixic acid (60.87%), Sulphamethoxazole-Trimethoprim, Doxycycline and Erythromycin (56.52% each). In total, 8 (17.02%) of the isolates were found to be ESBL positive. The prevalence of infections caused by virulent and highly drug resistant E. coli isolates constitute a risk of developing preterm birth complications in pregnant women and requires the selection of appropriate antibiotics for the treatment of infections caused during pregnancy.

A Magnetic Nanoparticle Based Nucleic Acid Isolation and Purification Instrument for DNA Extraction of Escherichia Coli O157: H7.

PubMed

Chen, Yahui; Lin, Jianhan; Jiang, Qin; Chen, Qi; Zhang, Shengjun; Li, Li

2016-03-01

The objective of this study was to evaluate the performance of a nucleic acid isolation and purification instrument using Escherichia coli O157:H7 as the model. The instrument was developed with magnetic nanoparticles for efficiently capturing nucleic acids and an intelligent mechanical unit for automatically performing the whole nucleic acid extraction process. A commercial DNA extraction kit from Huier Nano Company was used as reference. Nucleic acids in 1 ml of E. coli O157: H7 at a concentration of 5 x 10(8) CFU/mL were extracted by using this instrument and the kit in parallel and then detected by an ultraviolet spectrophotometer to obtain A260 values and A260/A280 values for the determination of the extracted DNA's quantity and purity, respectively. The A260 values for the instrument and the kit were 0.78 and 0.61, respectively, and the A260/A280 values were 1.98 and 1.93. The coefficient of variations of these parallel tests ranged from 10.5% to 16.7%. The results indicated that this nucleic acid isolation and purification instrument could extract a comparable level of nucleic acid within 50 min compared to the commercial DNA extraction kit.

Identical plasmid AmpC beta-lactamase genes and plasmid types in E. coli isolates from patients and poultry meat in the Netherlands.

PubMed

Voets, Guido M; Fluit, Ad C; Scharringa, Jelle; Schapendonk, Claudia; van den Munckhof, Thijs; Leverstein-van Hall, Maurine A; Stuart, James Cohen

2013-11-01

The increasing prevalence of third-generation cephalosporin-resistant Enterobacteriaceae is a worldwide problem. Recent studies showed that poultry meat and humans share identical Extended-Spectrum Beta-Lactamase genes, plasmid types, and Escherichia coli strain types, suggesting that transmission from poultry meat to humans may occur. The aim of this study was to compare plasmid-encoded Ambler class C beta-lactamase (pAmpC) genes, their plasmids, and bacterial strain types between E. coli isolates from retail chicken meat and clinical isolates in the Netherlands. In total, 98 Dutch retail chicken meat samples and 479 third-generation cephalosporin non-susceptible human clinical E. coli isolates from the same period were screened for pAmpC production. Plasmid typing was performed using PCR-based replicon typing (PBRT). E coli strains were compared using Multi-Locus-Sequence-Typing (MLST). In 12 of 98 chicken meat samples (12%), pAmpC producing E. coli were detected (all blaCMY-2). Of the 479 human E. coli, 25 (5.2%) harboured pAmpC genes (blaCMY-2 n = 22, blaACT n = 2, blaMIR n = 1). PBRT showed that 91% of poultry meat isolates harboured blaCMY-2 on an IncK plasmid, and 9% on an IncI1 plasmid. Of the human blaCMY-2 producing isolates, 42% also harboured blaCMY-2 on an IncK plasmid, and 47% on an IncI1 plasmid. Thus, 68% of human pAmpC producing E. coli have the same AmpC gene (blaCMY-2) and plasmid type (IncI1 or IncK) as found in poultry meat. MLST showed one cluster containing one human isolate and three meat isolates, with an IncK plasmid. These findings imply that a foodborne transmission route of blaCMY-2 harbouring plasmids cannot be excluded and that further evaluation is required. © 2013.

Evaluation of MLVA for epidemiological typing and outbreak detection of ESBL-producing Escherichia coli in Sweden.

PubMed

Helldal, Lisa; Karami, Nahid; Welinder-Olsson, Christina; Moore, Edward R B; Åhren, Christina

2017-01-06

To identify the spread of nosocomial infections and halt outbreak development caused by Escherichia coli that carry multiple antibiotic resistance factors, such as extended-spectrum beta-lactamases (ESBLs) and carbapenemases, is becoming demanding challenges due to the rapid global increase and constant and increasing influx of these bacteria from the community to the hospital setting. Our aim was to assess a reliable and rapid typing protocol for ESBL-E. coli, with the primary focus to screen for possible clonal relatedness between isolates. All clinical ESBL-E. coli isolates, collected from hospitals (n = 63) and the community (n = 41), within a single geographical region over a 6 months period, were included, as well as clinical isolates from a polyclonal outbreak (ST131, n = 9, and ST1444, n = 3). The sporadic cases represented 36 STs, of which eight STs dominated i.e. ST131 (n = 33 isolates), ST648 (n = 10), ST38 (n = 9), ST12 and 69 (each n = 4), ST 167, 405 and 372 (each n = 3). The efficacy of multiple-locus variable number tandem repeat analysis (MLVA) was evaluated using three, seven or ten loci, in comparison with that of pulsed-field gel electrophoresis (PFGE) and multi locus sequence typing (MLST). MLVA detected 39, 55 and 60 distinct types, respectively, using three (GECM-3), seven (GECM-7) or ten (GECM-10) loci. For GECM-7 and -10, 26 STs included one type and eleven STs each included several types, the corresponding numbers for GECM-3 were 29 and 8. The highest numbers were seen for ST131 (7,7 and 8 types, respectively), ST38 (5,5,8) and ST648 (4,5,5). Good concordance was observed with PFGE and GECM-7 and -10, despite fewer types being identified with MLVA; 78 as compared to 55 and 60 types. The lower discriminatory power of MLVA was primarily seen within the O25b-ST131 lineage (n = 34) and its H30-Rx subclone (n = 21). Epidemiologically unrelated O25b-ST131 isolates were clustered with O25b-ST131 outbreak isolates by MLVA, whereas the ST1444 outbreak isolates were accurately distinguished from unrelated isolates. MLVA, even when using only three loci, represents an easy initial typing tool for epidemiological screening of ESBL-E. coli. For the ST131-O25b linage, complementary methods may be needed to obtain sufficient resolution.

Whole-genome comparison of urinary pathogenic Escherichia coli and faecal isolates of UTI patients and healthy controls.

PubMed

Nielsen, Karen Leth; Stegger, Marc; Kiil, Kristoffer; Godfrey, Paul A; Feldgarden, Michael; Lilje, Berit; Andersen, Paal S; Frimodt-Møller, Niels

2017-12-01

The faecal flora is a common reservoir for urinary tract infection (UTI), and Escherichia coli (E. coli) is frequently found in this reservoir without causing extraintestinal infection. We investigated these E. coli reservoirs by whole-genome sequencing a large collection of E. coli from healthy controls (faecal), who had never previously had UTI, and from UTI patients (faecal and urinary) sampled from the same geographical area. We compared MLST types, phylogenetic relationship, accessory genome content and FimH type between patient and control faecal isolates as well as between UTI and faecal-only isolates, respectively. Comparison of the accessory genome of UTI isolates to faecal isolates revealed 35 gene families which were significantly more prevalent in the UTI isolates compared to the faecal isolates, although none of these were unique to one of the two groups. Of these 35, 22 belonged to a genomic island and three putatively belonged to a type VI secretion system (T6SS). MLST types and SNP phylogeny indicated no clustering of the UTI or faecal E. coli from patients distinct from the control faecal isolates, although there was an overrepresentation of UTI isolates belonging to clonal lineages CC73 and CC12. One combination of mutations in FimH, N70S/S78N, was significantly associated to UTI, while phylogenetic analysis of FimH and fimH identified no signs of distinct adaptation of UTI isolates compared to faecal-only isolates not causing UTI. In summary, the results showed that (i) healthy women who had never previously had UTI carried faecal E. coli which were overall closely related to UTI and faecal isolates from UTI patients; (ii) UTI isolates do not cluster separately from faecal-only isolates based on SNP analysis; and (iii) 22 gene families of a genomic island, putative T6SS proteins as well as specific metabolism and virulence associated proteins were significantly more common in UTI isolates compared to faecal-only isolates and (iv) evolution of fimH for these isolates was not linked to the clinical source of the isolates, apart from the mutation combination N70S/S78N, which was correlated to UTI isolates of phylogroup B2. Combined, these findings illustrate that faecal and UTI isolates, as well as faecal-only and faecal-UTI isolates, are closely related and can only be distinguished, if at all, by their accessory genome. Copyright © 2017 Elsevier GmbH. All rights reserved.

Multidrug resistance and extended-spectrum β-lactamases genes among Escherichia coli from patients with urinary tract infections in Northwestern Libya.

PubMed

Abujnah, Abubaker A; Zorgani, Abdulaziz; Sabri, Mohamed A M; El-Mohammady, Hanan; Khalek, Rania A; Ghenghesh, Khalifa S

2015-01-01

Multidrug resistance (MDR) and emergence of extended-spectrum β-lactamases (ESBLs) that mediate resistance to β-lactam drugs among Escherichia coli and other uropathogens have been reported worldwide. However, there is little information on the detection of ESBLs genes in E. coli from patients with urinary tract infections (UTIs) in the Arab countries using polymerase chain reaction (PCR), and in Libya such information is lacking. All patients attending Zawiya Teaching Hospital in Zawiya city between November 2012 and June 2013 suspected of having UTIs and from whom midstream urine samples were taken as part of the clinical workup were included in this prospective study. Samples were examined for uropathogens by standard bacteriological procedures. VITEK-2 automated microbiology system was used to identify the isolated uropathogens and determine the susceptibility of E. coli and Klebsiella spp. isolates to antimicrobials. In addition, phenotypically ESBLs-positive E. coli isolates were tested for ESBLs genes by PCR. The present study enrolled 1,790 patients with UTIs. Uropathogens were found in 371 (20.7%) urine specimens examined. Mixed pathogens were detected in two specimens with 373 total pathogens isolated. E. coli and Klebsiella spp. were the predominant uropathogens at 55.8% (208/373) and 18.5% (69/373), respectively. Other pathogens were detected in 25.7% (96/373) of urine samples. Of the E. coli and Klebsiella spp. tested, 69.2 and 100% were resistant to ampicillin, 6.7 and 33.3% to ceftriaxone, and 23.1 and 17.4% to ciprofloxacin, respectively. MDR (resistance to ≥3 antimicrobial groups) was found in 69 (33.2%) of E. coli and in 29 (42%) of Klebsiella spp. isolates. ESBLs were detected phenotypically in 14 (6.7%) of E. coli and in 15 (21.7%) of Klebsiella spp. isolates. Thirteen out of the 14 phenotypically ESBL-positive E. coli were positive for ESBL genes by PCR. bla TEM gene was detected in seven isolates, bla OXA gene in 10 isolates and bla CTX-M gene in six isolates. bla SHV gene was not detected in the present study. The isolation of MDR ESBL-producing uropathogens undoubtedly will limit the choices clinicians have to treat their patients with UTIs. Therefore, there is an urgent need for surveillance studies on antimicrobial resistance and prevalence of ESBLs among uropathogens to guide the clinical treatment of UTIs in Libya in the future.

Multidrug resistance and extended-spectrum β-lactamases genes among Escherichia coli from patients with urinary tract infections in Northwestern Libya

PubMed Central

Abujnah, Abubaker A.; Zorgani, Abdulaziz; Sabri, Mohamed A. M.; El-Mohammady, Hanan; Khalek, Rania A.; Ghenghesh, Khalifa S.

2015-01-01

Introduction Multidrug resistance (MDR) and emergence of extended-spectrum β-lactamases (ESBLs) that mediate resistance to β-lactam drugs among Escherichia coli and other uropathogens have been reported worldwide. However, there is little information on the detection of ESBLs genes in E. coli from patients with urinary tract infections (UTIs) in the Arab countries using polymerase chain reaction (PCR), and in Libya such information is lacking. Methods All patients attending Zawiya Teaching Hospital in Zawiya city between November 2012 and June 2013 suspected of having UTIs and from whom midstream urine samples were taken as part of the clinical workup were included in this prospective study. Samples were examined for uropathogens by standard bacteriological procedures. VITEK-2 automated microbiology system was used to identify the isolated uropathogens and determine the susceptibility of E. coli and Klebsiella spp. isolates to antimicrobials. In addition, phenotypically ESBLs-positive E. coli isolates were tested for ESBLs genes by PCR. Results The present study enrolled 1,790 patients with UTIs. Uropathogens were found in 371 (20.7%) urine specimens examined. Mixed pathogens were detected in two specimens with 373 total pathogens isolated. E. coli and Klebsiella spp. were the predominant uropathogens at 55.8% (208/373) and 18.5% (69/373), respectively. Other pathogens were detected in 25.7% (96/373) of urine samples. Of the E. coli and Klebsiella spp. tested, 69.2 and 100% were resistant to ampicillin, 6.7 and 33.3% to ceftriaxone, and 23.1 and 17.4% to ciprofloxacin, respectively. MDR (resistance to ≥3 antimicrobial groups) was found in 69 (33.2%) of E. coli and in 29 (42%) of Klebsiella spp. isolates. ESBLs were detected phenotypically in 14 (6.7%) of E. coli and in 15 (21.7%) of Klebsiella spp. isolates. Thirteen out of the 14 phenotypically ESBL-positive E. coli were positive for ESBL genes by PCR. bla TEM gene was detected in seven isolates, bla OXA gene in 10 isolates and bla CTX-M gene in six isolates. bla SHV gene was not detected in the present study. Conclusion The isolation of MDR ESBL-producing uropathogens undoubtedly will limit the choices clinicians have to treat their patients with UTIs. Therefore, there is an urgent need for surveillance studies on antimicrobial resistance and prevalence of ESBLs among uropathogens to guide the clinical treatment of UTIs in Libya in the future. PMID:25651907

Differential Distribution of Type II CRISPR-Cas Systems in Agricultural and Nonagricultural Campylobacter coli and Campylobacter jejuni Isolates Correlates with Lack of Shared Environments

PubMed Central

Pearson, Bruce M.; Louwen, Rogier; van Baarlen, Peter; van Vliet, Arnoud H.M.

2015-01-01

CRISPR (clustered regularly interspaced palindromic repeats)-Cas (CRISPR-associated) systems are sequence-specific adaptive defenses against phages and plasmids which are widespread in prokaryotes. Here we have studied whether phylogenetic relatedness or sharing of environmental niches affects the distribution and dissemination of Type II CRISPR-Cas systems, first in 132 bacterial genomes from 15 phylogenetic classes, ranging from Proteobacteria to Actinobacteria. There was clustering of distinct Type II CRISPR-Cas systems in phylogenetically distinct genera with varying G+C%, which share environmental niches. The distribution of CRISPR-Cas within a genus was studied using a large collection of genome sequences of the closely related Campylobacter species Campylobacter jejuni (N = 3,746) and Campylobacter coli (N = 486). The Cas gene cas9 and CRISPR-repeat are almost universally present in C. jejuni genomes (98.0% positive) but relatively rare in C. coli genomes (9.6% positive). Campylobacter jejuni and agricultural C. coli isolates share the C. jejuni CRISPR-Cas system, which is closely related to, but distinct from the C. coli CRISPR-Cas system found in C. coli isolates from nonagricultural sources. Analysis of the genomic position of CRISPR-Cas insertion suggests that the C. jejuni-type CRISPR-Cas has been transferred to agricultural C. coli. Conversely, the absence of the C. coli-type CRISPR-Cas in agricultural C. coli isolates may be due to these isolates not sharing the same environmental niche, and may be affected by farm hygiene and biosecurity practices in the agricultural sector. Finally, many CRISPR spacer alleles were linked with specific multilocus sequence types, suggesting that these can assist molecular epidemiology applications for C. jejuni and C. coli. PMID:26338188

Comparative assessment of inoculum effects on the antimicrobial activity of amoxycillin-clavulanate and piperacillin-tazobactam with extended-spectrum beta-lactamase-producing and extended-spectrum beta-lactamase-non-producing Escherichia coli isolates.

PubMed

López-Cerero, L; Picón, E; Morillo, C; Hernández, J R; Docobo, F; Pachón, J; Rodríguez-Baño, J; Pascual, A

2010-02-01

A significant inoculum-size effect has been observed with piperacillin-tazobactam, and has been associated with beta-lactamase production in extended-spectrum beta-lactamase (ESBL) producers. This association has not been previously studied in the case of amoxycillin-clavulanate. Piperacillin-tazobactam and amoxycillin-clavulanate were compared, using high inocula of susceptible strains either harbouring ESBLs or not. Two non-ESBL-producing and 15 amoxycillin-clavulanate-susceptible and piperacillin-tazobactam-susceptible ESBL-producing Escherichia coli isolates, and their respective transconjugants, were tested in dilution susceptibility tests using standard and 100-fold higher inocula. Three ESBL-producing strains and E. coli ATCC 25922 were selected for time-kill studies using standard and high initial inocula. At high inocula, MICs of piperacillin increased >eight-fold for non-ESBL-producing strains, and MICs of piperacillin-tazobactam (8:1 ratio or with tazobactam fixed at 4 mg/L) increased>eight-fold for all ESBL-producing strains. However, amoxycillin MICs were not affected by a high inoculum with non-ESBL-producing strains, whereas the MICs of amoxycillin-clavulanate (2:1 and 4:1) increased

High Levels of Antimicrobial Resistance among Escherichia coli Isolates from Livestock Farms and Synanthropic Rats and Shrews in the Mekong Delta of Vietnam

PubMed Central

Nhung, N. T.; Cuong, N. V.; Campbell, J.; Hoa, N. T.; Bryant, J. E.; Truc, V. N. T.; Kiet, B. T.; Jombart, T.; Trung, N. V.; Hien, V. B.; Thwaites, G.; Baker, S.

2014-01-01

In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P < 0.001). The prevalences of AMR among farmed species isolates (versus wild animals) were as follows: tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ∼8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R2 range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R2 range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. PMID:25398864

Determining the potential link between irrigation water quality and the microbiological quality of onions by phenotypic and genotypic characterization of Escherichia coli isolates.

PubMed

du Plessis, Erika M; Duvenage, Francois; Korsten, Lise

2015-04-01

The potential transfer of human pathogenic bacteria present in irrigation water onto fresh produce was investigated, because surface water sources used for irrigation purposes in South Africa have increasingly been reported to be contaminated with enteric bacterial pathogens. A microbiological analysis was performed of a selected river in Limpopo Province, South Africa, that is often contaminated with raw sewage from municipal sewage works and overhead irrigated onions produced on a commercial farm. Counts of Escherichia coli, coliforms, aerobic bacteria, fungi, and yeasts and the prevalence of E. coli O157:H7, Salmonella, and Listeria monocytogenes were determined. Identities of bacterial isolates from irrigation water and onions were confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrometry, PCR, and biochemical tests. To establish a potential link between the microbiological quality of the irrigation source and the onions, the E. coli isolates from both were subjected to antibiotic resistance, virulence gene, and enterobacterial repetitive intergenic consensus PCR analyses. River water E. coli counts exceeded South African Department of Water Affairs and World Health Organization irrigation water guidelines. Counts of aerobic bacteria, coliforms, fungi, and yeasts of onions from the market were acceptable according to Department of Health Directorate, Food Control, South Africa, microbiological guidelines for ready-to-eat fresh fruits and vegetables. E. coli O157:H7, Salmonella, and L. monocytogenes were not detected in onions, whereas only Salmonella was detected in 22% of water samples. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and PCR identification of E. coli isolates from water and onions correlated. Of the 45 E. coli isolates from water and onions, 42.2% were resistant to multiple antibiotics. Virulence genes eae, stx1, and stx2 were detected in 2.2, 6.6, and 2.2% of the E. coli isolates, respectively. Phenotypic (antimicrobial) and genotypic (virulence gene prevalence, DNA fingerprinting) analyses showed a link between river, dam, irrigation pivot point, and onion E. coli isolates.

An outbreak of Escherichia coli O157:H7 infection in southern Sweden associated with consumption of fermented sausage; aspects of sausage production that increase the risk of contamination

PubMed Central

SARTZ, L.; De JONG, B.; HJERTQVIST, M.; PLYM-FORSHELL, L.; ALSTERLUND, R.; LÖFDAHL, S.; OSTERMAN, B.; STÅHL, A.; ERIKSSON, E.; HANSSON, H.-B.; KARPMAN, D.

2008-01-01

SUMMARY A large outbreak of enterohaemorrhagic Escherichia coli (EHEC) infections occurred in southern Sweden during autumn 2002. A matched case-control study was performed and indicated an association between consumption of fermented sausage and EHEC infection (odds ratio 5·4, P<0·002). Pulsed-field gel electrophoresis analysis identified a strain of E. coli O157:H7 in clinical faecal isolates, which was identical to a strain isolated from sausage samples obtained from households of infected individuals. A combination of microbiological and epidemiological results established a link between sausage consumption and the outbreak in 30 out of a total of 39 investigated cases. Contaminated beef was suspected to be the source of infection. Delayed start of fermentation, lack of heat-treatment and a short curing period in cold temperature were identified as the main factors enabling EHEC survival. EHEC can survive throughout the entire production process of fermented sausage if curing conditions are inadequate. PMID:17445322

Atypical enteropathogenic Escherichia coli as aetiologic agents of sporadic and outbreak-associated diarrhoea in Brazil.

PubMed

Vieira, Melissa A; Dos Santos, Luís F; Dias, Regiane C B; Camargo, Carlos H; Pinheiro, Sandra R S; Gomes, Tânia A T; Hernandes, Rodrigo T

2016-09-01

Enteropathogenic Escherichia coli (EPEC) are important agents of diarrhoea in industrialized as well as developing countries, such as Brazil. The hallmark of EPEC pathogenesis is the establishment of attaching and effacing lesions in enterocytes, in which pedestal-like structures are formed underneath adherent bacteria. EPEC are divided into two subgroups, typical (tEPEC) and atypical (aEPEC), based on the presence of the EPEC adherence factor plasmid in tEPEC and its absence in aEPEC. This study was designed to characterize 82 aEPEC isolates obtained from stool samples of diarrhoeic patients during 2012 and 2013 in Brazil. The majority of the aEPEC were assigned to the phylo-group B1 (48.8 %), and intimin subtypes θ (20.7 %), β1 (9.7 %) and λ (9.7 %) were the most prevalent among the isolates. The nleB and nleE genes were concomitantly detected in 32.9 % of the isolates, demonstrating the occurrence of the pathogenicity island O122 among them. The O157-plasmid genes (ehxA and/or espP) were detected in 7.3 % of the isolates, suggesting that some aEPEC could be derived from Shiga-toxin-producing E. coli that lost the stx genes while trafficking in the host. PFGE of 14 aEPEC of serotypes O2 : H16, O33 : H34, O39 : H9, O108 : H- and ONT : H19 isolated from five distinct outbreaks showed serotype-specific PFGE clusters, indicating a high degree of similarity among the isolates from the same event, thus highlighting these serotypes as potential aetiologic agents of diarrhoeal outbreaks in Brazil.

Occurrence of multi-antibiotic resistant Pseudomonas spp. in drinking water produced from karstic hydrosystems.

PubMed

Flores Ribeiro, Angela; Bodilis, Josselin; Alonso, Lise; Buquet, Sylvaine; Feuilloley, Marc; Dupont, Jean-Paul; Pawlak, Barbara

2014-08-15

Aquatic environments could play a role in the spread of antibiotic resistance genes by enabling antibiotic-resistant bacteria transferred through wastewater inputs to connect with autochthonous bacteria. Consequently, drinking water could be a potential pathway to humans and animals for antibiotic resistance genes. The aim of this study was to investigate occurrences of Escherichia coli and Pseudomonas spp. in drinking water produced from a karst, a vulnerable aquifer with frequent increases in water turbidity after rainfall events and run-offs. Water samples were collected throughout the system from the karstic springs to the drinking water tap during three non-turbid periods and two turbid events. E. coli densities in the springs were 10- to 1000-fold higher during the turbid events than during the non-turbid periods, indicating that, with increased turbidity, surface water had entered the karstic system and contaminated the spring water. However, no E. coli were isolated in the drinking water. In contrast, Pseudomonas spp. were isolated from the drinking water only during turbid events, while the densities in the springs were from 10- to 100-fold higher than in the non-turbid periods. All the 580 Pseudomonas spp. isolates obtained from the sampling periods were resistant (to between 1 and 10 antibiotics), with similar resistance patterns. Among all the Pseudomonas isolated throughout the drinking water production system, between 32% and 86% carried the major resistance pattern: ticarcillin, ticarcillin-clavulanic acid, cefsulodin, and/or aztreonam, and/or sulfamethoxazol-trimethoprim, and/or fosfomycin. Finally, 8 Pseudomonas spp. isolates, related to the Pseudomonas putida and Pseudomonas fluorescens species, were isolated from the drinking water. Thus, Pseudomonas could be involved in the dissemination of antibiotic resistance via drinking water during critical periods. Copyright © 2014 Elsevier B.V. All rights reserved.

Inhibitory activity of cheese whey fermented with kefir grains.

PubMed

Londero, A; Quinta, R; Abraham, A G; Sereno, R; De Antoni, G; Garrote, G L

2011-01-01

We investigated the chemical and microbiological compositions of three types of whey to be used for kefir fermentation as well as the inhibitory capacity of their subsequent fermentation products against 100 Salmonella sp. and 100 Escherichia coli pathogenic isolates. All the wheys after fermentation with 10% (wt/vol) kefir grains showed inhibition against all 200 isolates. The content of lactic acid bacteria in fermented whey ranged from 1.04 × 10(7) to 1.17 × 10(7) CFU/ml and the level of yeasts from 2.05 × 10(6) to 4.23 × 10(6) CFU/ml. The main changes in the chemical composition during fermentation were a decrease in lactose content by 41 to 48% along with a corresponding lactic acid production to a final level of 0.84 to 1.20% of the total reaction products. The MIC was a 30% dilution of the fermentation products for most of the isolates, while the MBC varied between 40 and 70%, depending on the isolate. The pathogenic isolates Salmonella enterica serovar Enteritidis 2713 and E. coli 2710 in the fermented whey lost their viability after 2 to 7 h of incubation. When pathogens were deliberately inoculated into whey before fermentation, the CFU were reduced by 2 log cycles for E. coli and 4 log cycles for Salmonella sp. after 24 h of incubation. The inhibition was mainly related to lactic acid production. This work demonstrated the possibility of using kefir grains to ferment an industrial by-product in order to obtain a natural acidic preparation with strong bacterial inhibitory properties that also contains potentially probiotic microorganisms.

O-Antigens of Escherichia coli Strains O81 and HS3-104 Are Structurally and Genetically Related, Except O-Antigen Glucosylation in E. coli HS3-104.

PubMed

Zdorovenko, E L; Wang, Y; Shashkov, A S; Chen, T; Ovchinnikova, O G; Liu, B; Golomidova, A K; Babenko, V V; Letarov, A V; Knirel, Y A

2018-05-01

Glycerophosphate-containing O-specific polysaccharides (OPSs) were obtained by mild acidic degradation of lipopolysaccharides isolated from Escherichia coli type strain O81 and E. coli strain HS3-104 from horse feces. The structures of both OPSs and of the oligosaccharide derived from the strain O81 OPS by treatment with 48% HF were studied by monosaccharide analysis and one- and two-dimensional 1H- and 13C-NMR spectroscopy. Both OPSs had similar structures and differed only in the presence of a side-chain glucose residue in the strain HS3-104 OPS. The genes and the organization of the O-antigen biosynthesis gene cluster in both strains are almost identical with the exception of the gtr gene cluster responsible for glucosylations in the strain HS3-104, which is located elsewhere in the genome.

The microbiological safety of duckweed fed chickens: a risk assessment of using duckweed reared on domestic wastewater as a protein source in broiler chickens

NASA Astrophysics Data System (ADS)

Moyo, S.; Dalu, J. M.; Ndamba, J.

The possibility of transmission of pathogens from duckweed supplemented feed to chickens and consequently to the human consumer necessitated the microbiological testing of duckweed fed chickens. This assessment was thus done to determine whether there is transmission of pathogens from the duckweed supplemented feed to the chickens; determine whether such infection would be systemic or be confined to the gastro-intestinal tract of the birds; and to investigate the microbial load and distribution of the microbes with age. The study birds were sacrificed at 3, 6, 8 and 10 weeks of age and examined for the indicator organisms Escherichia coli and Salmonella spp. There was no discernible pattern in the microbial load of both the duckweed fed chickens and control birds with age although the control birds sampled clearly had a lower microbial load than the experimental flock. Some Salmonella and two enteropathogenic E. coli strains were isolated from control and experimental sub-samples at 3 weeks. There were no Salmonellae isolated in the subsequent batches of birds and feed although a number of E. coli were isolated. More isolates were obtained from the three weeks’ sub-samples (collected during wet weather) than from all the other sub-samples. The use of duckweed at this inclusion rate under the processing conditions at Nemanwa was thus concluded to be microbiologically safe as long as due caution is exercised during the processing of the duckweed and handling of the birds. There are indications that the chickens may get contaminated especially during wet weather as evidenced by the isolation of E. coli and Salmonella spp from the first batch sub-samples. This was attributed to poor environmental sanitation at the plant particularly in view of the prevailing wet conditions at the time.

Fecal Carriage of Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae Strains Is Associated with Worse Outcome in Patients Hospitalized in the Pediatric Oncology Unit of Beni-Messous Hospital in Algiers, Algeria.

PubMed

Medboua-Benbalagh, Chafiaa; Touati, Abdelaziz; Kermas, Rachida; Gharout-Sait, Alima; Brasme, Lucien; Mezhoud, Halima; Touati, Djamila; Guillard, Thomas; de Champs, Christophe

2017-09-01

The current study aimed to investigate extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) fecal carriage in children with different cancers admitted in the pediatric oncology unit of Beni-Messous Hospital (Algiers, Algeria). Rectal swabs from children with cancer were sampled from February 2012 to May 2013 within 48 hours following their admission. After species identification and detection of ESBL production by double-disk synergy test (DD test), antibiotic susceptibility was determined by the standard disk diffusion method. Antibiotic resistance genes, including bla genes and plasmid-mediated quinolone resistance (PMQR) genes, were investigated by polymerase chain reaction (PCR). The phylogenetic grouping of Escherichia coli strains was determined by PCR. Of the 171 children studied, 93 (54%) were ESBL carriers. An antibiotic treatment for the last 3 months before admission (p = 0.01), hematological malignancies (p = 0.003), and death (p = 0.0003) were more frequent in the ESBL-E group than in the non-ESBL group. Multivariate analysis showed that hematological malignancies (odds ratio [OR]: 3.9; confidence interval [CI]: 1.1-14.1; p = 0.04) and ESBL-E carriage (OR: 6.2; CI: 1.7-22.00; p = 0.005) were two independent factors associated with increased risk of death. A total of 103 ESBL-E isolates were obtained. Klebsiella pneumoniae and E. coli isolates were the most frequently isolated. PCR amplification showed that all the isolates produced a CTX-M ESBL (CTX-M-15, CTX-M-14, and CTX-M-3). The PMQR genes detected were qnrB, qnrS, and aac(6')-Ib-cr. E. coli isolates were assigned to four major extraintestinal pathogenic E. coli phylogroups, including B2 and D. This study provides, for the first time, insight into epidemiology of the ESBL-E fecal carriage among children with cancer in Algeria.

Inhibitor-resistant TEM- and OXA-1-producing Escherichia coli isolates resistant to amoxicillin-clavulanate are more clonal and possess lower virulence gene content than susceptible clinical isolates.

PubMed

Oteo, Jesús; González-López, Juan José; Ortega, Adriana; Quintero-Zárate, J Natalia; Bou, Germán; Cercenado, Emilia; Conejo, María Carmen; Martínez-Martínez, Luis; Navarro, Ferran; Oliver, Antonio; Bartolomé, Rosa M; Campos, José

2014-07-01

In a previous prospective multicenter study in Spain, we found that OXA-1 and inhibitor-resistant TEM (IRT) β-lactamases constitute the most common plasmid-borne mechanisms of genuine amoxicillin-clavulanate (AMC) resistance in Escherichia coli. In the present study, we investigated the population structure and virulence traits of clinical AMC-resistant E. coli strains expressing OXA-1 or IRT and compared these traits to those in a control group of clinical AMC-susceptible E. coli isolates. All OXA-1-producing (n = 67) and IRT-producing (n = 45) isolates were matched by geographical and temporal origin to the AMC-susceptible control set (n = 56). We performed multilocus sequence typing and phylogenetic group characterization for each isolate and then studied the isolates for the presence of 49 virulence factors (VFs) by PCR and sequencing. The most prevalent clone detected was distinct for each group: group C isolates of sequence type (ST) 88 (C/ST88) were the most common in OXA-1 producers, B2/ST131 isolates were the most common in IRT producers, and B2/ST73 isolates were the most common in AMC-susceptible isolates. The median numbers of isolates per ST were 3.72 in OXA-1 producers, 2.04 in IRT producers, and 1.69 in AMC-susceptible isolates; the proportions of STs represented by one unique isolate in each group were 19.4%, 31.1%, and 48.2%, respectively. The sum of all VFs detected, calculated as a virulence score, was significantly higher in AMC-susceptible isolates than OXA-1 and IRT producers (means, 12.5 versus 8.3 and 8.2, respectively). Our findings suggest that IRT- and OXA-1-producing E. coli isolates resistant to AMC have a different and less diverse population structure than AMC-susceptible clinical E. coli isolates. The AMC-susceptible population also contains more VFs than AMC-resistant isolates. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Prevalence, antimicrobial resistance and genetic diversity of Campylobacter coli and Campylobacter jejuni in Ecuadorian broilers at slaughter age

PubMed Central

Vinueza-Burgos, Christian; Wautier, Magali; Martiny, Delphine; Cisneros, Marco; Van Damme, Inge; De Zutter, Lieven

2017-01-01

Abstract Thermotolerant Campylobacter spp. are a major cause of foodborne gastrointestinal infections worldwide. The linkage of human campylobacteriosis and poultry has been widely described. In this study we aimed to investigate the prevalence, antimicrobial resistance and genetic diversity of C. coli and C. jejuni in broilers from Ecuador. Caecal content from 379 randomly selected broiler batches originating from 115 farms were collected from 6 slaughterhouses located in the province of Pichincha during 1 year. Microbiological isolation was performed by direct plating on mCCDA agar. Identification of Campylobacter species was done by PCR. Minimum inhibitory concentration (MIC) values for gentamicin, ciprofloxacin, nalidixic acid, tetracycline, streptomycin, and erythromycin were obtained. Genetic variation was assessed by RFLP-flaA typing and Multilocus Sequence Typing (MLST) of selected isolates. Prevalence at batch level was 64.1%. Of the positive batches 68.7% were positive for C. coli, 18.9% for C. jejuni, and 12.4% for C. coli and C. jejuni. Resistance rates above 67% were shown for tetracycline, ciprofloxacin, and nalidixic acid. The resistance pattern tetracycline, ciprofloxin, and nalidixic acid was the dominant one in both Campylobacter species. RFLP-flaA typing analysis showed that C. coli and C. jejuni strains belonged to 38 and 26 profiles respectively. On the other hand MLST typing revealed that C. coli except one strain belonged to CC-828, while C. jejuni except 2 strains belonged to 12 assigned clonal complexes (CCs). Furthermore 4 new sequence types (STs) for both species were described, whereby 2 new STs for C. coli were based on new allele sequences. Further research is necessary to estimate the impact of the slaughter of Campylobacter positive broiler batches on the contamination level of carcasses in slaughterhouses and at retail in Ecuador. PMID:28339716

Comparative study of three xenic media culture for cultivation of Balantidium coli strains.

PubMed

Barbosa, Alynne da Silva; Cardozo, Matheus Lessa; Dib, Laís Verdan; Fonseca, Ana Beatriz Monteiro; Uchôa, Claudia Maria Antunes; Bastos, Otilio Machado Pereira; Amendoeira, Maria Regina Reis

2018-01-01

The aim of the present study was to evaluate the growth rate of Balantidium coli in three xenic media cultures. Between 2013 and 2015, 10 B. coli isolates obtained from feces of Cynomolgus macaques, and 30 isolates from feces of pigs were studied. An inoculum of 500 trophozoites was transferred to tubes containing LES, TYSGM-9 and Pavlova media. These cultures were evaluated at incubation times of 24, 48, 72 and 96 hours. In most of strains analyzed wasn't showed significant difference in the growth rate comparing TYSGM-9 and Pavlova media (Wilcoxon p>0.016). In Pavlova medium, the trophozoites showed a maximum growth at 72 hours with significant difference when compared with the times of 24 h and 96 h (Wilcoxon <0.008). In LES, viable trophozoites were observed until 24 hours, with a significant difference (Friedman p<0.05, Wilcoxon p<0.016) in the number of parasite cells compared with Pavlova and TYSGM-9 media cultures. Thus, LES medium seemed to be less adequate than the other media for maintenance of B. coli. Despite the satisfactory results in TYSGM-9, Pavlova medium was considered ideal for the maintenance of this protozoan strain, guaranteeing the viability of the parasite with subculture every three days, presenting lower costs.

Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German outbreak strain and of STEC strains isolated in Spain.

PubMed

Mora, Azucena; Herrrera, Alexandra; López, Cecilia; Dahbi, Ghizlane; Mamani, Rosalia; Pita, Julia M; Alonso, María P; Llovo, José; Bernárdez, María I; Blanco, Jesús E; Blanco, Miguel; Blanco, Jorge

2011-09-01

A Shiga-toxin-producing Escherichia coli (STEC) strain belonging to serotype O104:H4, phylogenetic group B1 and sequence type ST678, with virulence features common to the enteroaggregative E. coli (EAEC) pathotype, was reported as the cause of the recent 2011 outbreak in Germany. The outbreak strain was determined to carry several virulence factors of extraintestinal pathogenic E. coli (ExPEC) and to be resistant to a wide range of antibiotics. There are only a few reports of serotype O104:H4, which is very rare in humans and has never been detected in animals or food. Several research groups obtained the complete genome sequence of isolates of the German outbreak strain as well as the genome sequences of EAEC of serotype O104:H4 strains from Africa. Those findings suggested that horizontal genetic transfer allowed the emergence of the highly virulent Shiga-toxin-producing enteroaggregative E. coli (STEAEC) O104:H4 strain responsible for the outbreak in Germany. Epidemiologic investigations supported a linkage between the outbreaks in Germany and France and traced their origin to fenugreek seeds imported from Africa. However, there has been no isolation of the causative strain O104:H4 from any of the samples of fenugreek seeds analyzed. Following the German outbreak, we conducted a large sampling to analyze the presence of STEC, EAEC, and other types of diarrheagenic E. coli strains in Spanish vegetables. During June and July 2011, 200 vegetable samples from different origins were analyzed. All were negative for the virulent serotype O104:H4 and only one lettuce sample (0.6%) was positive for a STEC strain of serotype O146:H21 (stx1, stx2), considered of low virulence. Despite the single positive case, the hygienic and sanitary quality of Spanish vegetables proved to be quite good. In 195 of the 200 samples (98%), <10 colony-forming units (cfu) of E. coli per gram were detected, and the microbiological levels of all samples were satisfactory (<100 cfu/g). The samples were also negative for other pathotypes of diarrheagenic E. coli (EAEC, ETEC, tEPEC, and EIEC). Consistent with data from other countries, STEC belonging to serotype O157:H7 and other serotypes have been isolated from beef, milk, cheese, and domestic (cattle, sheep, goats) and wild (deer, boar, fox) animals in Spain. Nevertheless, STEC outbreaks in Spain are rare.

Comparative Genomics of Escherichia coli Isolated from Skin and Soft Tissue and Other Extraintestinal Infections.

PubMed

Ranjan, Amit; Shaik, Sabiha; Nandanwar, Nishant; Hussain, Arif; Tiwari, Sumeet K; Semmler, Torsten; Jadhav, Savita; Wieler, Lothar H; Alam, Munirul; Colwell, Rita R; Ahmed, Niyaz

2017-08-15

Escherichia coli , an intestinal Gram-negative bacterium, has been shown to be associated with a variety of diseases in addition to intestinal infections, such as urinary tract infections (UTIs), meningitis in neonates, septicemia, skin and soft tissue infections (SSTIs), and colisepticemia. Thus, for nonintestinal infections, it is categorized as extraintestinal pathogenic E. coli (ExPEC). It is also an opportunistic pathogen, causing cross infections, notably as an agent of zoonotic diseases. However, comparative genomic data providing functional and genetic coordinates for ExPEC strains associated with these different types of infections have not proven conclusive. In the study reported here, ExPEC E. coli isolated from SSTIs was characterized, including virulence and drug resistance profiles, and compared with isolates from patients suffering either pyelonephritis or septicemia. Results revealed that the majority of the isolates belonged to two pathogenic phylogroups, B2 and D. Approximately 67% of the isolates were multidrug resistant (MDR), with 85% producing extended-spectrum beta-lactamase (ESBL) and 6% producing metallo-beta-lactamase (MBL). The bla CTX-M-15 genotype was observed in at least 70% of the E. coli isolates in each category, conferring resistance to an extended range of beta-lactam antibiotics. Whole-genome sequencing and comparative genomics of the ExPEC isolates revealed that two of the four isolates from SSTIs, NA633 and NA643, belong to pandemic sequence type ST131, whereas functional characteristics of three of the ExPEC pathotypes revealed that they had equal capabilities to form biofilm and were resistant to human serum. Overall, the isolates from a variety of ExPEC infections demonstrated similar resistomes and virulomes and did not display any disease-specific functional or genetic coordinates. IMPORTANCE Infections caused by extraintestinal pathogenic E. coli (ExPEC) are of global concern as they result in significant costs to health care facilities management. The recent emergence of a multidrug-resistant pandemic clone, Escherichia coli ST131, is of primary concern as a global threat. In developing countries, such as India, skin and soft tissue infections (SSTIs) associated with E. coli are marginally addressed. In this study, we employed both genomic analysis and phenotypic assays to determine relationships, if any, among the ExPEC pathotypes. Similarity between antibiotic resistance and virulence profiles was observed, ST131 isolates from SSTIs were reported, and genomic similarities among strains isolated from different disease conditions were detected. This study provides functional molecular infection epidemiology insight into SSTI-associated E. coli compared with ExPEC pathotypes. Copyright © 2017 Ranjan et al.

Salmonella enterica and extended-spectrum cephalosporin-resistant Escherichia coli recovered from Holstein dairy calves from 8 farms in New Brunswick, Canada.

PubMed

Awosile, Babafela; McClure, J; Sanchez, Javier; Rodriguez-Lecompte, Juan Carlos; Keefe, Greg; Heider, Luke C

2018-04-01

This study was carried out to determine the frequency of fecal carriage, antimicrobial susceptibility, and resistance genes in Salmonella enterica and Escherichia coli with reduced susceptibility to extended-spectrum cephalosporins (ESC) isolated from 488 dairy calves from 8 farms in New Brunswick, Canada. Both S. enterica and E. coli with reduced susceptibility to ESC were isolated using selective culture. Minimum inhibitory concentrations to a panel of antimicrobial drugs were determined for randomly selected E. coli isolates and all of the Salmonella isolates. Multiplex PCR were conducted on the selected ESC-resistant E. coli to assess the β-lactamase resistance genes (bla CTX-M , bla CMY-2 , bla SHV , and bla TEM ) and plasmid-mediated qnrB and qnrS resistant genes. Information on ceftiofur use and other farm management practices were collected by the use of a questionnaire to determine the risk factors for the fecal recovery of E. coli with reduced susceptibility to ESC. Salmonella enterica frequency in calves' fecal samples was 3.3%, and all were pansusceptible. Salmonella isolates belonged to 3 serovars namely Salmonella Senftenberg, Salmonella Typhimurium, and Salmonella Derby. The frequency of fecal carriage of E. coli with reduced susceptibility to ESC in calves was 81.2%. Of the selected isolates (n = 100), all were multi-drug resistant, whereas 88% were ESC resistant based on minimum inhibitory concentration testing. From the selected ESC-resistant E. coli isolates, bla TEM was detected in 84.1%, bla CMY-2 was detected in 52.2%, bla CTXM groups were detected in 30.7%, and bla SHV was detected in 1.1% of isolates. Plasmid-mediated quinolone resistance genes were identified in 7 of 9 isolates resistant to quinolones. Five isolates were positive for qnrB, whereas 2 isolates were positive for both qnrB and qnrS. Whereas neonatal calves [odds ratio (OR) = 2.42, 95% confidence interval (CI): 1.87-3.12], regular ceftiofur use on the farm (OR = 3.83, 95% CI: 2.29-6.39), feeding of unpasteurized nonsalable milk (OR = 1.6, 95% CI: 1.18-2.18), and use of florfenicol (OR = 2.02, 95% CI: 1.43-2.86) were statistically associated with fecal recovery of E. coli with reduced susceptibility to ESC, use of ceftiofur for the treatment of respiratory diseases (OR = 0.57, 95% CI: 0.41-0.79) was statistically associated with decreased recovery of E. coli with reduced susceptibility to ESC. This study has provided information on the resistance genes associated with the occurrence of ESC and fluoroquinolone resistance in dairy calves within this region. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Escherichia coli isolates from patients with bacteremic urinary tract infection are genetically distinct from those derived from sepsis following prostate transrectal biopsy.

PubMed

Dan, Michael; Yair, Yael; Samosav, Alex; Gottesman, Tamar; Yossepowitch, Orit; Harari-Schwartz, Orna; Tsivian, Alexander; Schreiber, Rachel; Gophna, Uri

2015-01-01

Transrectal ultrasound-guided (TRUS) prostate biopsy is a very common procedure that is generally considered relatively safe. However, severe sepsis can occur after TRUS prostate biopsies, with Escherichia coli being the predominant causative agent. A common perception is that the bacteria that cause post-TRUS prostate biopsy infections originate in the urinary tract, but this view has not been adequately tested. Yet other authors believe on the basis of indirect evidence that the pathogens are introduced into the bloodstream by the biopsy needle after passage through the rectal mucosa. We compared E. coli isolates from male patients with bacteremic urinary tract infection (B-UTI) to isolates of patients with post prostate biopsy sepsis (PPBS), in terms of their sequence types, determined by multi-locus sequence typing (MLST) and their virulence markers. B-UTI isolates were much richer in virulence genes than were PPBS isolates, supporting the hypothesis that E. coli causing PPBS derive directly from the rectum. Sequence type 131 (ST131) strains and related strain from the ST131 were common (>30%) among the E. coli isolates from PPBS patients as well as from B-UTI patients and all these strains expressed extended spectrum beta-lactamases. Our finding supports the hypothesis that E. coli causing PPBS derive directly from the rectum, bypassing the urinary tract, and therefore do not require many of the virulence capabilities necessary for an E. coli strain that must persist in the urinary tract. In light of the increasing prevalence of highly resistant E. coli strains, a new approach for prevention of PPBS is urgently required. Copyright © 2015. Published by Elsevier GmbH.

Changing plasmid types responsible for extended spectrum cephalosporin resistance in Escherichia coli O157:H7 in the United States, 1996–2009

PubMed Central

Folster, J. P.; Pecic, G.; Stroika, S.; Rickert, R.; Whichard, J.

2015-01-01

Escherichia coli O157 is a major cause of foodborne illness. Plasmids are genetic elements that mobilize antimicrobial resistance determinants including blaCMY β-lactamases that confer resistance to extended-spectrum cephalosporins (ESC). ESCs are important for treating a variety of infections. IncA/C plasmids are found among diverse sources, including cattle, the principal source of E. coli O157 infections in humans. IncI1 plasmids are common among E. coli and Salmonella from poultry and other avian sources. To broaden our understanding of reservoirs of blaCMY, we determined the types of plasmids carrying blaCMY among E. coli O157. From 1996 to 2009, 3742 E. coli O157 isolates were tested. Eleven (0.29%) were ceftriaxone resistant and had a blaCMY-2-containing plasmid. All four isolates submitted before 2001 and a single 2001 isolate had blaCMY encoded on IncA/C plasmids, while all five isolates submitted after 2001 and a single 2001 isolate had blaCMY carried on IncI1 plasmids. The IncI1 plasmids were ST2, ST20, and ST23. We conclude that cephalosporin resistance among E. coli O157:H7 is due to plasmid-encoded blaCMY genes and that plasmid types appear to have shifted from IncA/C to IncI1. This shift suggests either a change in plasmid type among animal reservoirs or that the organism has expanded into avian reservoirs. More analysis of human, retail meat, and food animal isolates is necessary to broaden our understanding of the antimicrobial resistance determinants of ESC resistance among E. coli O157. PMID:26478858

Distinct Transcriptional Profiles and Phenotypes Exhibited by Escherichia coli O157:H7 Isolates Related to the 2006 Spinach-Associated Outbreak

PubMed Central

Kyle, Jennifer L.; Huynh, Steven; Carter, Michelle Q.; Brandl, Maria T.; Mandrell, Robert E.

2012-01-01

In 2006, a large outbreak of Escherichia coli O157:H7 was linked to the consumption of ready-to-eat bagged baby spinach in the United States. The likely sources of preharvest spinach contamination were soil and water that became contaminated via cattle or feral pigs in the proximity of the spinach fields. In this study, we compared the transcriptional profiles of 12 E. coli O157:H7 isolates that possess the same two-enzyme pulsed-field gel electrophoresis (PFGE) profile and are related temporally or geographically to the above outbreak. These E. coli O157:H7 isolates included three clinical isolates, five isolates from separate bags of spinach, and single isolates from pasture soil, river water, cow feces, and a feral pig. The three clinical isolates and two spinach bag isolates grown in cultures to stationary phase showed decreased expression of many σS-regulated genes, including gadA, osmE, osmY, and katE, compared with the soil, water, cow, feral pig, and the other three spinach bag isolates. The decreased expression of these σS-regulated genes was correlated with the decreased resistance of the isolates to acid stress, osmotic stress, and oxidative stress but increases in scavenging ability. We also observed that intraisolate variability was much more pronounced among the clinical and spinach isolates than among the environmental isolates. Together, the transcriptional and phenotypic differences of the spinach outbreak isolates of E. coli O157:H7 support the hypothesis that some variants within the spinach bag retained characteristics of the preharvest isolates, whereas other variants with altered gene expression and phenotypes infected the human host. PMID:22081562

Comparison of broad-spectrum cephalosporin-resistant Escherichia coli isolated from dogs and humans in Hokkaido, Japan.

PubMed

Okubo, Torahiko; Sato, Toyotaka; Yokota, Shin-ichi; Usui, Masaru; Tamura, Yutaka

2014-04-01

Resistance to broad-spectrum cephalosporins (BSCs) in Enterobacteriaceae in companion animals has become a great concern for public health. To estimate the dissemination of BSC-resistant bacteria between dog and human, we examined the BSC-resistance determinants of and genetic similarities between 69 BSC-resistant Escherichia coli isolates derived from canine rectal swabs (n = 28) and human clinical samples (n = 41). Some E. coli isolates possessed blaTEM-1b (14 canine and 16 human isolates), blaCTx-M-2 (6 human isolates), blaCTx-M-14 (3 canine and 14 human isolates), blaCTx-M-27 (1 canine and 15 human isolates), and blaCMY-2 (11 canine and 3 human isolates). The possession of CTX-M-type β-lactamases was significantly more frequent in human isolates, whereas CMY-2 was more common in canine isolates. Bacterial typing methods (phylogenetic typing, O-antigen serotyping, and pulsed-field gel electrophoresis) showed little clonal relationship between canine isolates and human isolates. Plasmid analysis and Southern blotting indicated that the plasmids encoding CMY-2 were similar among canine and human isolates. Based on the differences in the major β-lactamase and the divergence of bacterial types between canine and human isolates, it seems that clonal dissemination of BSC-resistant E. coli between canines and humans is limited. The similarity of the CMY-2-encoding plasmid suggests that plasmid-mediated β-lactamase gene transmission plays a role in interspecies diffusion of BSC-resistant E. coli between dog and human. Copyright © 2013 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

A systematic review and meta-analysis of the epidemiology of pathogenic Escherichia coli of calves and the role of calves as reservoirs for human pathogenic E. coli.

PubMed

Kolenda, Rafał; Burdukiewicz, Michał; Schierack, Peter

2015-01-01

Escherichia coli bacteria are the most common causes of diarrhea and septicemia in calves. Moreover, calves form a major reservoir for transmission of pathogenic E. coli to humans. Systematic reviews and meta-analyses of publications on E. coli as calf pathogens and the role of calves as reservoir have not been done so far. We reviewed studies between 1951 and 2013 reporting the presence of virulence associated factors (VAFs) in calf E. coli and extracted the following information: year(s) and country of sampling, animal number, health status, isolate number, VAF prevalence, serotypes, diagnostic methods, and biological assays. The prevalence of VAFs or E. coli pathotypes was compared between healthy and diarrheic animals and was analyzed for time courses. Together, 106 papers with 25,982 E. coli isolates from 27 countries tested for VAFs were included. F5, F17, and F41 fimbriae and heat-stable enterotoxin (ST) - VAFs of enterotoxigenic E. coli (ETEC) were significantly associated with calf diarrhea. On the contrary, ETEC VAF F4 fimbriae and heat-labile enterotoxin as well as enteropathogenic (EPEC), Shiga toxin-producing (STEC), and enterohemorrhagic E. coli (EHEC) were not associated with diarrhea. The prevalence increased overtime for ST-positive isolates, but decreased for F5- and STEC-positive isolates. Our study provides useful information about the history of scientific investigations performed in this domain so far, and helps to define etiological agents of calf disease, and to evaluate calves as reservoir hosts for human pathogenic E. coli.

Assessing host-specificity of Escherichia coli using a supervised learning logic-regression-based analysis of single nucleotide polymorphisms in intergenic regions.

PubMed

Zhi, Shuai; Li, Qiaozhi; Yasui, Yutaka; Edge, Thomas; Topp, Edward; Neumann, Norman F

2015-11-01

Host specificity in E. coli is widely debated. Herein, we used supervised learning logic-regression-based analysis of intergenic DNA sequence variability in E. coli in an attempt to identify single nucleotide polymorphism (SNP) biomarkers of E. coli that are associated with natural selection and evolution toward host specificity. Seven-hundred and eighty strains of E. coli were isolated from 15 different animal hosts. We utilized logic regression for analyzing DNA sequence data of three intergenic regions (flanked by the genes uspC-flhDC, csgBAC-csgDEFG, and asnS-ompF) to identify genetic biomarkers that could potentially discriminate E. coli based on host sources. Across 15 different animal hosts, logic regression successfully discriminated E. coli based on animal host source with relatively high specificity (i.e., among the samples of the non-target animal host, the proportion that correctly did not have the host-specific marker pattern) and sensitivity (i.e., among the samples from a given animal host, the proportion that correctly had the host-specific marker pattern), even after fivefold cross validation. Permutation tests confirmed that for most animals, host specific intergenic biomarkers identified by logic regression in E. coli were significantly associated with animal host source. The highest level of biomarker sensitivity was observed in deer isolates, with 82% of all deer E. coli isolates displaying a unique SNP pattern that was 98% specific to deer. Fifty-three percent of human isolates displayed a unique biomarker pattern that was 98% specific to humans. Twenty-nine percent of cattle isolates displayed a unique biomarker that was 97% specific to cattle. Interestingly, even within a related host group (i.e., Family: Canidae [domestic dogs and coyotes]), highly specific SNP biomarkers (98% and 99% specificity for dog and coyotes, respectively) were observed, with 21% of dog E. coli isolates displaying a unique dog biomarker and 61% of coyote isolates displaying a unique coyote biomarker. Application of a supervised learning method, such as logic regression, to DNA sequence analysis at certain intergenic regions demonstrates that some E. coli strains may evolve to become host-specific. Copyright © 2015 Elsevier Inc. All rights reserved.

Induction of bacteremia in newborn rats by Escherichia coli K1 is correlated with only certain O (lipopolysaccharide) antigen types.

PubMed

Pluschke, G; Mercer, A; Kusećek, B; Pohl, A; Achtman, M

1983-02-01

A total of 95 Escherichia coli strains (O1:K1, O7:K1, or O18:K1), obtained from different sources of human infections and from healthy individuals, were analyzed for the ability to cause bacteremia after colonizing the gut of newborn rats. Strains of all three serotypes were able to multiply extensively in the gut after oral inoculation and to translocate (in small numbers) to the mesenteric lymph nodes. With only few exceptions, O7:K1 and O18:K1 strains were able to cause bacteremia, while O1:K1 strains could not. Mixed-infection experiments revealed that the bacteria present in the blood during a case of bacteremia are in most cases the descendants of one cell that has multiplied extraintestinally after translocation to the mesenteric lymph nodes. It appears that virulent O7:K1 and O18:K1, but not avirulent O1:K1, bacteria are able to multiply directly in the bloodstream of the newborn rats. No correlation between virulence and the source of isolation of the different strains was observed. Disease isolates thus do not seem to differ from fecal isolates of the same serotype in special virulence properties. The differences in virulence among different O serotypes of K1 E. coli observed in the rat model were comparable to their relative frequency of isolation from meningitis in newborn children.

Molecular epidemiology of Escherichia coli O157:H7 strains by bacteriophage lambda restriction fragment length polymorphism analysis: application to a multistate foodborne outbreak and a day-care center cluster.

PubMed

Samadpour, M; Grimm, L M; Desai, B; Alfi, D; Ongerth, J E; Tarr, P I

1993-12-01

Genomic DNAs prepared from 168 isolates of Escherichia coli O157:H7 were analyzed for restriction fragment length polymorphisms on Southern blots probed with bacteriophage lambda DNA. The isolates analyzed included strains from a recent large multistate outbreak of E. coli O157:H7 infection associated with consumption of poorly cooked beef in restaurants, a day-care center cluster, and temporally and geographically unrelated isolates. E. coli O157:H7 isolates recovered from the incriminated meat and from 61 (96.8%) of 63 patients from Washington and Nevada possessed identical lambda restriction fragment length patterns. The lambda restriction fragment length polymorphisms observed in 11 (91.7%) of 12 day-care center patients were identical, but they differed from that of the strain associated with the multistate outbreak. E. coli O157:H7 from 42 patients temporally or geographically unrelated to either cluster of infection possessed unique and different lambda restriction fragment length patterns, except for paired isolates from three separate clusters of infection. These data demonstrate that the hybridization of DNA digests of E. coli O157:H7 with radiolabelled bacteriophage lambda DNA can be a useful, stable, and discriminatory epidemiologic tool for analyzing the linkage between strains of E. coli O157:H7.

Comparison of Six Chromogenic Agar Media for the Isolation of a Broad Variety of Non-O157 Shigatoxin-Producing Escherichia coli (STEC) Serogroups

PubMed Central

Verhaegen, Bavo; De Reu, Koen; Heyndrickx, Marc; De Zutter, Lieven

2015-01-01

The isolation of non-O157 STEC from food samples has proved to be challenging. The selection of a suitable selective isolation agar remains problematic. The purpose of this study was to qualitatively and quantitatively evaluate six chromogenic agar media for the isolation of STEC: Tryptone Bile X-glucuronide agar (TBX), Rainbow® Agar O157 (RB), Rapid E. coli O157:H7 (RE), Modified MacConkey Agar (mMac), CHROMagarTM STEC (Chr ST) and chromIDTM EHEC (Chr ID). During this study, 45 E. coli strains were used, including 39 STEC strains belonging to 16 different O serogroups and 6 non-STEC E. coli. All E. coli strains were able to grow on TBX and RB, whereas one STEC strain was unable to grow on Chr ID and a number of other STEC strains did not grow on mMac, CHROMagar STEC and Rapid E. coli O157:H7. However, only the latter three agars were selective enough to completely inhibit the growth of the non-STEC E. coli. Our conclusion was that paired use of a more selective agar such as CHROMagar STEC together with a less selective agar like TBX or Chr ID might be the best solution for isolating non-O157 STEC from food. PMID:26090610

Comparison of Six Chromogenic Agar Media for the Isolation of a Broad Variety of Non-O157 Shigatoxin-Producing Escherichia coli (STEC) Serogroups.

PubMed

Verhaegen, Bavo; De Reu, Koen; Heyndrickx, Marc; De Zutter, Lieven

2015-06-17

The isolation of non-O157 STEC from food samples has proved to be challenging. The selection of a suitable selective isolation agar remains problematic. The purpose of this study was to qualitatively and quantitatively evaluate six chromogenic agar media for the isolation of STEC: Tryptone Bile X-glucuronide agar (TBX), Rainbow® Agar O157 (RB), Rapid E. coli O157:H7 (RE), Modified MacConkey Agar (mMac), CHROMagarTM STEC (Chr ST) and chromIDTM EHEC (Chr ID). During this study, 45 E. coli strains were used, including 39 STEC strains belonging to 16 different O serogroups and 6 non-STEC E. coli. All E. coli strains were able to grow on TBX and RB, whereas one STEC strain was unable to grow on Chr ID and a number of other STEC strains did not grow on mMac, CHROMagar STEC and Rapid E. coli O157:H7. However, only the latter three agars were selective enough to completely inhibit the growth of the non-STEC E. coli. Our conclusion was that paired use of a more selective agar such as CHROMagar STEC together with a less selective agar like TBX or Chr ID might be the best solution for isolating non-O157 STEC from food.

First report of extended-spectrum β-lactamases among clinical isolates of Escherichia coli in Gaza Strip, Palestine.

PubMed

Tayh, Ghassan; Ben Sallem, Rym; Ben Yahia, Houssem; Gharsa, Haythem; Klibi, Naouel; Boudabous, Abdellatif; Ben Slama, Karim

2016-09-01

This study aimed to assess the occurrence of extended-spectrum β-lactamases (ESBLs) in clinical Escherichia coli isolates from Palestine and to characterise their type, genetic environments and associated resistance genes. Twenty-seven broad-spectrum-cephalosporin-resistant E. coli isolates were recovered between April and June 2013 in Gaza Strip hospitals. Characterisation of ESBL genes and their genetic environments, detection of associated resistance genes, and the presence and characterisation of integrons were performed by PCR and sequencing. The clonal relationship among ESBL-positive E. coli strains was determined by pulsed-field gel electrophoresis (PFGE) using the restriction enzyme XbaI. Phylogroup typing and virulence factors were studied by PCR. The following ESBL genes were identified: blaCTX-M-15 (21 isolates); blaCTX-M-14a (2 isolates); blaCTX-M-1 (2 isolates); blaCTX-M-3 (1 isolate); and blaCTX-M-27 (1 isolate). The blaTEM-1 gene was also detected in eight CTX-M-producing strains. The ISEcp1 sequence was found upstream of blaCTX-M in 23 isolates, and orf477 was found downstream of this gene in 24 isolates. IS903 was also detected downstream in three isolates. Six isolates carried class 1 integrons with the gene cassette arrangement dfrA17-aadA5. High clonal diversity was observed among the studied isolates by PFGE (24 unrelated profiles). The virulence gene fimA was detected in 23 isolates, the aer gene in 8 isolates and the papC gene in 7 isolates. The studied isolates belonged to phylogroups B2 (12 isolates), D (12 isolates) and A (3 isolates). This is the first report of the detection of CTX-M class β-lactamases in E. coli of clinical origin in Gaza Strip hospitals. Copyright © 2016 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Molecular characterisation of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates from hospital and ambulatory patients in Germany.

PubMed

Pietsch, Michael; Eller, Christoph; Wendt, Constanze; Holfelder, Martin; Falgenhauer, Linda; Fruth, Angelika; Grössl, Tobias; Leistner, Rasmus; Valenza, Giuseppe; Werner, Guido; Pfeifer, Yvonne

2017-02-01

The increase of Escherichia coli producing extended-spectrum β-lactamases (ESBL) in hospitals and their emergence as intestinal colonisers of healthy humans is of concern. Transmission ways and the extent of spread of distinct E. coli clones or ESBL genes among humans and animals via the food chain or the environment is a matter of debate. In this study we determined ESBL genotypes in E. coli isolates (n=233) resistant to 3rd generation cephalosporins from hospitals and medical practices using PCR and sequencing. Bacterial strain typing was performed by PCR-based phylogrouping, multilocus sequence typing (MLST) and a ST131-specific PCR. Results showed that CTX-M-15 (50.4%), CTX-M-1 (28.4%) and CTX-M-14 (5.6%) were the most common ESBL types. Especially, CTX-M-15 was associated with E. coli ST131 of phylogenetic group B2, which was the dominant sequence type among our isolates (35.8%). MLST typing revealed 40 different sequence types (STs), with ST131, ST410, ST10 and ST38 as the most prevalent ones. Our findings give an overview of the current distribution of ESBL-producing E. coli isolates from humans in Germany. E. coli O25b:H4-ST131 was confirmed to be the most common clone, which is known for its successful dissemination worldwide. Although heterogeneity among the isolates was found, several successful clones previously described in animals (ST410, ST10) also occurred in our isolate collection. Further detailed investigations of ESBL-producing isolates from different habitats are needed to evaluate possible transfer ways. Copyright © 2015 Elsevier B.V. All rights reserved.

Leukemia and risk of recurrent Escherichia coli bacteremia: genotyping implicates E. coli translocation from the colon to the bloodstream.

PubMed

Samet, A; Sledzińska, A; Krawczyk, B; Hellmann, A; Nowicki, S; Kur, J; Nowicki, B

2013-11-01

In patients with leukemia, the portal(s) and reasons for the persistence of an Escherichia coli recurrent bacteremia remain unclear. Adult Hematology Clinic (AHC) databases at the State Clinical Hospital in Gdańsk were reviewed to evaluate the frequency of E. coli bacteremia between 2002 and 2005. Blood and bowel E. coli strains were obtained and the genetic relatedness of the strains was analyzed. The rate of E. coli bacteremia per 1,000 admissions at the AHC was higher (85.0) than in the other clinics of the hospital (2.9), p < 0.001. A higher mortality was observed in patients with a history of E. coli versus non-E. coli bacteremia [30/95 (31 %) vs. 53/430 (12 %), p < 0.001]; 72.8 % of patients with leukemia had an unknown source of bacteremia. In 2005, 6 out of 25 (24 %) patients with leukemia had ≥2 episodes of E. coli-positive blood cultures. These gastrointestinal E. coli isolates were replaced within 3-8 weeks with a new E. coli H genotype. A recurrent episode of bacteremia was usually caused by an infection with a transient E. coli H genotype identical to that found in the subject's bowel. Consistent with the definition of bowel/blood translocation, the bowel appeared to be a portal for E. coli in these subjects and, hence, a clear source for their recurring bacteremia.

Escherichia coli isolates causing asymptomatic bacteriuria in catheterized and noncatheterized individuals possess similar virulence properties.

PubMed

Watts, Rebecca E; Hancock, Viktoria; Ong, Cheryl-Lynn Y; Vejborg, Rebecca Munk; Mabbett, Amanda N; Totsika, Makrina; Looke, David F; Nimmo, Graeme R; Klemm, Per; Schembri, Mark A

2010-07-01

Urinary tract infections (UTIs) are among the most common infectious diseases of humans, with Escherichia coli being responsible for >80% of all cases. Asymptomatic bacteriuria (ABU) occurs when bacteria colonize the urinary tract without causing clinical symptoms and can affect both catheterized patients (catheter-associated ABU [CA-ABU]) and noncatheterized patients. Here, we compared the virulence properties of a collection of ABU and CA-ABU nosocomial E. coli isolates in terms of antibiotic resistance, phylogenetic grouping, specific UTI-associated virulence genes, hemagglutination characteristics, and biofilm formation. CA-ABU isolates were similar to ABU isolates with regard to the majority of these characteristics; exceptions were that CA-ABU isolates had a higher prevalence of the polysaccharide capsule marker genes kpsMT II and kpsMT K1, while more ABU strains were capable of mannose-resistant hemagglutination. To examine biofilm growth in detail, we performed a global gene expression analysis with two CA-ABU strains that formed a strong biofilm and that possessed a limited adhesin repertoire. The gene expression profile of the CA-ABU strains during biofilm growth showed considerable overlap with that previously described for the prototype ABU E. coli strain, 83972. This is the first global gene expression analysis of E. coli CA-ABU strains. Overall, our data suggest that nosocomial ABU and CA-ABU E. coli isolates possess similar virulence profiles.

Rapid and reliable discrimination between Shigella species and Escherichia coli using MALDI-TOF mass spectrometry.

PubMed

Paauw, Armand; Jonker, Debby; Roeselers, Guus; Heng, Jonathan M E; Mars-Groenendijk, Roos H; Trip, Hein; Molhoek, E Margo; Jansen, Hugo-Jan; van der Plas, Jan; de Jong, Ad L; Majchrzykiewicz-Koehorst, Joanna A; Speksnijder, Arjen G C L

2015-01-01

E. coli-Shigella species are a cryptic group of bacteria in which the Shigella species are distributed within the phylogenetic tree of E. coli. The nomenclature is historically based and the discrimination of these genera developed as a result of the epidemiological need to identify the cause of shigellosis, a severe disease caused by Shigella species. For these reasons, this incorrect classification of shigellae persists to date, and the ability to rapidly characterize E. coli and Shigella species remains highly desirable. Until recently, existing matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) assays used to identify bacteria could not discriminate between E. coli and Shigella species. Here we present a rapid classification method for the E. coli-Shigella phylogroup based on MALDI-TOF MS which is supported by genetic analysis. E. coli and Shigella isolates were collected and genetically characterized by MLVA. A custom reference library for MALDI-TOF MS that represents the genetic diversity of E. coli and Shigella strains was developed. Characterization of E. coli and Shigella species is based on an approach with Biotyper software. Using this reference library it was possible to distinguish between Shigella species and E. coli. Of the 180 isolates tested, 94.4% were correctly classified as E. coli or shigellae. The results of four (2.2%) isolates could not be interpreted and six (3.3%) isolates were classified incorrectly. The custom library extends the existing MALDI-TOF MS method for species determination by enabling rapid and accurate discrimination between Shigella species and E. coli. Copyright © 2015 Elsevier GmbH. All rights reserved.

Complete genome sequences of two atypical enteropathogenic Escherichia coli O145 environmental strains

USDA-ARS?s Scientific Manuscript database

Escherichia coli O145 strains RM14715 and RM14723 were isolated from wildlife feces near a leafy greens-growing region in Yuma, Arizona. Both strains carry a distinct genotype compared with the E. coli O145 strains isolated from Salinas Valley, California. Here we report complete genome sequences an...

Adhesion, biofilm and genotypic characteristics of antimicrobial resistant Escherichia coli isolates.

PubMed

Cergole-Novella, Maria C; Pignatari, Antonio C C; Guth, Beatriz E C

2015-03-01

Aggregative adherence to human epithelial cells, most to renal proximal tubular (HK-2) cells, and biofilm formation was identified among antimicrobial resistant Escherichia coli strains mainly isolated from bacteremia. The importance of these virulence properties contributing to host colonization and infection associated with multiresistant E. coli should not be neglected.

Epidemiology and Characteristics of Escherichia coli Sequence Type 131 (ST131) from Long-Term Care Facility Residents Colonized Intestinally with Fluoroquinolone-Resistant Escherichia coli

PubMed Central

Han, Jennifer H.; Garrigan, Charles; Johnston, Brian; Nachamkin, Irving; Clabots, Connie; Bilker, Warren B.; Santana, Evelyn; Tolomeo, Pam; Maslow, Joel; Myers, Janice; Carson, Lesley; Lautenbach, Ebbing; Johnson, James R.

2016-01-01

The objective of this study was to evaluate molecular and epidemiologic factors associated with Escherichia coli sequence type 131 (ST131) among long-term care facility (LTCF) residents who acquired gastrointestinal tract colonization with fluoroquinolone-resistant E. coli (FQREC). Colonizing isolates from 37 residents who newly developed FQREC colonization at three LTCFs from 2006–2008 were evaluated. Twenty-nine (78%) of 37 total FQREC colonizing isolates were ST131. Most ST131 isolates had a distinctive combination of gyrA and parC replacement mutations. The ST131 and non-ST131 isolates differed significantly for the prevalence of many individual virulence factors but not for the proportion that qualified molecularly as extraintestinal pathogenic E. coli (ExPEC) or aggregate virulence factor scores. E. coli ST131 was highly prevalent among LTCF residents with FQREC colonization. Future studies should determine the risk factors for infection among ST131-colonized residents, and assess the potential for increased transmissibility of ST131 in the long-term care setting. PMID:27939288

Quantifying Antimicrobial Resistance at Veal Calf Farms

PubMed Central

Bosman, Angela B.; Wagenaar, Jaap; Stegeman, Arjan; Vernooij, Hans; Mevius, Dik

2012-01-01

This study was performed to determine a sampling strategy to quantify the prevalence of antimicrobial resistance on veal calf farms, based on the variation in antimicrobial resistance within and between calves on five farms. Faecal samples from 50 healthy calves (10 calves/farm) were collected. From each individual sample and one pooled faecal sample per farm, 90 selected Escherichia coli isolates were tested for their resistance against 25 mg/L amoxicillin, 25 mg/L tetracycline, 0.5 mg/L cefotaxime, 0.125 mg/L ciprofloxacin and 8/152 mg/L trimethoprim/sulfamethoxazole (tmp/s) by replica plating. From each faecal sample another 10 selected E. coli isolates were tested for their resistance by broth microdilution as a reference. Logistic regression analysis was performed to compare the odds of testing an isolate resistant between both test methods (replica plating vs. broth microdilution) and to evaluate the effect of pooling faecal samples. Bootstrap analysis was used to investigate the precision of the estimated prevalence of resistance to each antimicrobial obtained by several simulated sampling strategies. Replica plating showed similar odds of E. coli isolates tested resistant compared to broth microdilution, except for ciprofloxacin (OR 0.29, p≤0.05). Pooled samples showed in general lower odds of an isolate being resistant compared to individual samples, although these differences were not significant. Bootstrap analysis showed that within each antimicrobial the various compositions of a pooled sample provided consistent estimates for the mean proportion of resistant isolates. Sampling strategies should be based on the variation in resistance among isolates within faecal samples and between faecal samples, which may vary by antimicrobial. In our study, the optimal sampling strategy from the perspective of precision of the estimated levels of resistance and practicality consists of a pooled faecal sample from 20 individual animals, of which 90 isolates are tested for their susceptibility by replica plating. PMID:22970313

No evidence for a bovine mastitis Escherichia coli pathotype.

PubMed

Leimbach, Andreas; Poehlein, Anja; Vollmers, John; Görlich, Dennis; Daniel, Rolf; Dobrindt, Ulrich

2017-05-08

Escherichia coli bovine mastitis is a disease of significant economic importance in the dairy industry. Molecular characterization of mastitis-associated E. coli (MAEC) did not result in the identification of common traits. Nevertheless, a mammary pathogenic E. coli (MPEC) pathotype has been proposed suggesting virulence traits that differentiate MAEC from commensal E. coli. The present study was designed to investigate the MPEC pathotype hypothesis by comparing the genomes of MAEC and commensal bovine E. coli. We sequenced the genomes of eight E. coli isolated from bovine mastitis cases and six fecal commensal isolates from udder-healthy cows. We analyzed the phylogenetic history of bovine E. coli genomes by supplementing this strain panel with eleven bovine-associated E. coli from public databases. The majority of the isolates originate from phylogroups A and B1, but neither MAEC nor commensal strains could be unambiguously distinguished by phylogenetic lineage. The gene content of both MAEC and commensal strains is highly diverse and dominated by their phylogenetic background. Although individual strains carry some typical E. coli virulence-associated genes, no traits important for pathogenicity could be specifically attributed to MAEC. Instead, both commensal strains and MAEC have very few gene families enriched in either pathotype. Only the aerobactin siderophore gene cluster was enriched in commensal E. coli within our strain panel. This is the first characterization of a phylogenetically diverse strain panel including several MAEC and commensal isolates. With our comparative genomics approach we could not confirm previous studies that argue for a positive selection of specific traits enabling MAEC to elicit bovine mastitis. Instead, MAEC are facultative and opportunistic pathogens recruited from the highly diverse bovine gastrointestinal microbiota. Virulence-associated genes implicated in mastitis are a by-product of commensalism with the primary function to enhance fitness in the bovine gastrointestinal tract. Therefore, we put the definition of the MPEC pathotype into question and suggest to designate corresponding isolates as MAEC.

Phenotypic and molecular detection of BLACTX-M gene extended-spectrum beta-lactamases in escherichia coli and klebsiella pneumoniae of north sumatera isolates

NASA Astrophysics Data System (ADS)

Hasibuan, Mirzan; Suryanto, Dwi; Lia Kusumawati, R.

2018-03-01

The application of antibiotics expanded-spectrum third-generation cephalosporin for the treatment of infectious diseases in hospitals is known contribute to increasing resistance due to the presence of the blaCTX-M gene in the bacteria producing ESBLs. This study was aimed to detect ESBLs, isolate phenotype and blaCTX-M genes on Escherichia coli and Klebsiella pneumoniae collected from H. Adam Malik Central Hospital. Phenotypes of the bacterial were detection using Vitek two compact, while the blaCTX-M genes were detection using polymerase chain reaction technique. The results showed that 85 (100%) isolates were ESBLs consisted of 41(48%) of Escherichia coli, and 44 (52%) of Klebsiella pneumoniae, respectively. blaCTX-M genes were detection in 62 (72.94%) of the isolates which 31 (36.47%) were Escherichia coli, and 31 (36.47%) of the isolates were Klebsiella pneumoniae, respectively. This study indicates the high prevalence of blaCTX-M genes in Escherichia coli and Klebsiella pneumoniea causing bacterial antibiotic resistance.

Genome Sequences of 228 Shiga Toxin-Producing Escherichia coli Isolates and 12 Isolates Representing Other Diarrheagenic E. coli Pathotypes

PubMed Central

Strockbine, Nancy; Changayil, Shankar; Ranganathan, Satishkumar; Zhao, Kun; Weil, Ryan; MacCannell, Duncan; Sabol, Ashley; Schmidtke, Amber; Martin, Haley; Stripling, Devon; Ribot, Efrain M.; Gerner-Smidt, Peter

2014-01-01

Shiga toxin-producing Escherichia coli (STEC) are a common cause for food-borne diarrheal illness outbreaks and sporadic cases. Here, we report the availability of the draft genome sequences of 228 STEC strains representing 32 serotypes with known pulsed-field gel electrophoresis (PFGE) types and epidemiological relationships, as well as 12 strains representing other diarrheagenic E. coli pathotypes. PMID:25103754

Isolation of an Aptamer that Binds Specifically to E. coli

PubMed Central

Cleto, Fernanda; Krieger, Marco Aurélio; Cardoso, Josiane

2016-01-01

Escherichia coli is a bacterial species found ubiquitously in the intestinal flora of animals, although pathogenic variants cause major public health problems. Aptamers are short oligonucleotides that bind to targets with high affinity and specificity, and have great potential for use in diagnostics and therapy. We used cell-based Systematic Evolution of Ligands by EXponential enrichment (cell-SELEX) to isolate four single stranded DNA (ssDNA) aptamers that bind strongly to E. coli cells (ATCC generic strain 25922), with Kd values in the nanomolar range. Fluorescently labeled aptamers label the surface of E. coli cells, as viewed by fluorescent microscopy. Specificity tests with twelve different bacterial species showed that one of the aptamers–called P12-31—is highly specific for E. coli. Importantly, this aptamer binds to Meningitis/sepsis associated E. coli (MNEC) clinical isolates, and is the first aptamer described with potential for use in the diagnosis of MNEC-borne pathologies. PMID:27104834

Characterization of Escherichia coli O157:H7 in New Zealand using multiple-locus variable-number tandem-repeat analysis.

PubMed

Dyet, K H; Robertson, I; Turbitt, E; Carter, P E

2011-03-01

Recently, multiple-locus variable-number tandem-repeat analysis (MLVA) has been proposed as an alternative to pulsed-field gel electrophoresis (PFGE) for characterization of Escherichia coli O157:H7. In this study we characterized 118 E. coli O157:H7 isolates from cases of gastrointestinal disease in New Zealand using XbaI PFGE profiles and a MLVA scheme that assessed variability in eight polymorphic loci. The 118 isolates characterized included all 80 E. coli O157:H7 referred to New Zealand's Enteric Reference Laboratory in 2006 and 29 phage-type 2 isolates from 2005. When applied to these isolates the discriminatory power of PFGE and MLVA was not significantly different. However, MLVA data may be more epidemiologically relevant as isolates from family clusters of disease had identical MLVA profiles, even when the XbaI PFGE profiles differed slightly. Furthermore, most isolates with indistinguishable XbaI PFGE profiles that did not appear to be epidemiologically related had distinct MLVA profiles.

Phenotypic and Genotypic Changes over Time and across Facilities of Serial Colonizing and Infecting Escherichia coli Isolates Recovered from Injured Service Members

PubMed Central

Beckius, Miriam L.; Zera, Wendy C.; Yu, Xin; Cheatle, Kristelle A.; Aggarwal, Deepak; Li, Ping; Lloyd, Bradley A.; Tribble, David R.; Weintrob, Amy C.; Murray, Clinton K.

2014-01-01

Escherichia coli is the most common colonizing and infecting organism isolated from U.S. service members injured during deployment. Our objective was to evaluate the phenotypic and genotypic changes of infecting and colonizing E. coli organisms over time and across facilities to better understand their transmission patterns. E. coli isolates were collected via surveillance cultures and infection workups from U.S. military personnel injured during deployment (June 2009 to May 2011). The isolates underwent antimicrobial susceptibility testing, pulsed-field gel electrophoresis, and multiplex PCR for phylotyping to determine their resistance profiles and clonality. A total of 343 colonizing and 136 infecting E. coli isolates were analyzed, of which 197 (57%) and 109 (80%) isolates, respectively, produced extended-spectrum β-lactamases (ESBL). Phylogroup A was predominant among both colonizing (38%) and infecting isolates (43%). Although 188 unique pulsed-field types (PFTs) were identified from the colonizing isolates, and 54 PFTs were identified from the infecting isolates, there was a lack of PFT overlap between study years, combat zones, and military treatment facilities. On a per-subject basis, 26% and 32% of the patients with serial colonizing isolates and 10% and 21% with serial infecting isolates acquired changes in their phylogroup and PFT profiles, respectively, over time. The production of ESBL remained high over time and across facilities, with no substantial changes in antimicrobial susceptibilities. Overall, our results demonstrated an array of genotypic and phenotypic differences for the isolates without large clonal clusters; however, the same PFTs were occasionally observed in the colonizing and infecting isolates, suggesting that the source of infections may be endogenous host organisms. PMID:25143566

High prevalence of Escherichia coli sequence type 131 among antimicrobial-resistant E. coli isolates from geriatric patients.

PubMed

Ho, Pak-Leung; Chu, Yuki Pui-Shan; Lo, Wai-U; Chow, Kin-Hung; Law, Pierra Y; Tse, Cindy Wing-Sze; Ng, Tak-Keung; Cheng, Vincent Chi-Chung; Que, Tak-Lun

2015-03-01

Previous work on the subclones within Escherichia coli ST131 predominantly involved isolates from Western countries. This study assessed the prevalence and antimicrobial resistance attributed to this clonal group. A total of 340 consecutive, non-duplicated urinary E. coli isolates originating from four clinical laboratories in Hong Kong in 2013 were tested. ST131 prevalence among the total isolates was 18.5 % (63/340) and was higher among inpatient isolates (23.0 %) than outpatient isolates (11.8 %, P<0.001), and higher among isolates from patients aged ≥65 years than from patients aged 18-50 years and 51-64 years (25.4 vs 3.4 and 4.0 %, respectively, P<0.001). Of the 63 ST131 isolates, 43 (68.3 %) isolates belonged to the H30 subclone, whereas the remaining isolates belonged to H41 (n = 17), H54 (n = 2) and H22 (n = 1). All H30 isolates were ciprofloxacin-resistant, of which 18.6 % (8/43) belonged to the H30-Rx subclone. Twenty-six (41.3 %) ST131 isolates were ESBL-producers, of which 19 had blaCTX-M-14 (12 non-H30-Rx, two H30-Rx and five H41), six had blaCTX-M-15 (five non-H30-Rx and one H30-Rx) and one was blaCTX-M-negative (H30). In conclusion, ST131 accounts for a large share of the antimicrobial-resistant E. coli isolates from geriatric patients. Unlike previous reports, ESBL-producing ST131 strains mainly belonged to non-H30-Rx rather than the H30-Rx subclone, with blaCTX-M-14 as the dominant enzyme type. © 2015 The Authors.

In vitro activity of rifaximin against clinical isolates of Escherichia coli and other enteropathogenic bacteria isolated from travellers returning to the UK.

PubMed

Hopkins, Katie L; Mushtaq, Shazad; Richardson, Judith F; Doumith, Michel; de Pinna, Elizabeth; Cheasty, Tom; Wain, John; Livermore, David M; Woodford, Neil

2014-05-01

Rifaximin is licensed in the EU and USA for treating travellers' diarrhoea caused by non-invasive bacteria. Selection for resistance mechanisms of public health significance might occur if these are linked to rifamycin resistance. Rifaximin MICs were determined by agar dilution for 90 isolates each of Escherichia coli, Shigella spp., nontyphoidal Salmonella enterica, typhoidal S. enterica and Campylobacter spp., an additional 60 E. coli with CTX-M ESBLs isolated from patients with travellers' diarrhoea, and 30 non-diarrhoeal carbapenemase-producing E. coli. Comparators were rifampicin, ciprofloxacin, azithromycin, trimethoprim/sulfamethoxazole and doxycycline. Isolates with rifaximin MICs>32 mg/L were screened for arr genes, and critical rpoB regions were sequenced. Rifaximin was active at ≤32 mg/L against 436/450 (96.9%) diverse Enterobacteriaceae, whereas 81/90 (90%) Campylobacter spp. were resistant to rifaximin at ≥128 mg/L. Rifaximin MICs were ≥128 mg/L for two Shigella and five MDR E. coli producing NDM (n = 3), OXA-48 (n = 1) or CTX-M-15 (n = 1). Two of the five MDR E. coli had plasmids harbouring arr-2 together with bla(NDM), and two (one each with bla(NDM) and bla(CTX-M-15)) had His526Asn substitutions in RpoB. The rifamycin resistance mechanism remained undefined in one MDR E. coli isolate (with bla(OXA-48)) and the two Shigella isolates. Rifaximin showed good in vitro activity against diverse Enterobacteriaceae but was largely inactive against Campylobacter spp. Rifaximin has potential to co-select MDR E. coli in the gut flora, but much stronger associations were seen between ESBL and/or carbapenemase production and resistance to alternative treatments for travellers' diarrhoea, notably ciprofloxacin and azithromycin. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Molecular Epidemiology of Campylobacter coli Strains Isolated from Different Sources in New Zealand between 2005 and 2014

PubMed Central

Grinberg, Alex; Midwinter, Anne C.; Marshall, Jonathan C.; Collins-Emerson, Julie M.; French, Nigel P.

2016-01-01

ABSTRACT Campylobacteriosis is one of the most important foodborne diseases worldwide and a significant health burden in New Zealand. Campylobacter jejuni is the predominant species worldwide, accounting for approximately 90% of human cases, followed by Campylobacter coli. Most studies in New Zealand have focused on C. jejuni; hence, the impact of C. coli strains on human health is not well understood. The aim of this study was to genotype C. coli isolates collected in the Manawatu region of New Zealand from clinical cases, fresh poultry meat, ruminant feces, and environmental water sources, between 2005 and 2014, to study their population structure and estimate the contribution of each source to the burden of human disease. Campylobacter isolates were identified by PCR and typed by multilocus sequence typing. C. coli accounted for 2.9% (n = 47/1,601) of Campylobacter isolates from human clinical cases, 9.6% (n = 108/1,123) from poultry, 13.4% (n = 49/364) from ruminants, and 6.4% (n = 11/171) from water. Molecular subtyping revealed 27 different sequence types (STs), of which 18 belonged to clonal complex ST-828. ST-1581 was the most prevalent C. coli sequence type isolated from both human cases (n = 12/47) and poultry (n = 44/110). When classified using cladistics, all sequence types belonged to clade 1 except ST-7774, which belonged to clade 2. ST-854, ST-1590, and ST-4009 were isolated only from human cases and fresh poultry, while ST-3232 was isolated only from human cases and ruminant sources. Modeling indicated ruminants and poultry as the main sources of C. coli human infection. IMPORTANCE We performed a molecular epidemiological study of Campylobacter coli infection in New Zealand, one of few such studies globally. This study analyzed the population genetic structure of the bacterium and included a probabilistic source attribution model covering different animal and water sources. The results are discussed in a global context. PMID:27208097

Bacteraemia due to non-ESBL-producing Escherichia coli O25b:H4 sequence type 131: insights into risk factors, clinical features and outcomes.

PubMed

Morales-Barroso, Isabel; López-Cerero, Lorena; Molina, José; Bellido, Mar; Navarro, María Dolores; Serrano, Lara; González-Galán, Verónica; Praena, Julia; Pascual, Alvaro; Rodríguez-Baño, Jesús

2017-04-01

The epidemiology and outcomes of bloodstream infections (BSIs) caused by Escherichia coli ST131 isolates not producing extended-spectrum β-lactamases (ESBLs) are not well defined despite being more prevalent than ESBL-producers. In this study, risk factors and the impact on outcome of BSIs caused by non-ESBL-producing ST131 E. coli versus non-ST131 E. coli were investigated. A case-control study was performed in two tertiary centres to identify risk factors for ST131. Molecular methods were used to investigate all E. coli isolates from blood cultures for those belonging to O25b:H4-ST131 clonal group. fimH alleles were characterised in ST131 isolates. Multivariate analysis was performed by logistic regression or Cox regression as appropriate. A total of 33 ST131 E. coli cases and 56 controls were studied. ST131 isolates showed higher rates of resistance to ampicillin and ciprofloxacin; fimH alleles were H30 in 14 isolates (42.4%) and H22 in 12 isolates (36.4%). Only recent surgery (OR = 7.03, 95% CI 1.71-28.84; P = 0.007) and unknown source of bacteraemia (OR = 5.37, 95% CI 0.93-30.81; P = 0.05) were associated with ST131. ST131 isolates showed no association with 30-day mortality, therapeutic failure, presentation with severe sepsis/shock or length of stay. Bacteraemia due to non-ESBL-producing O25b:H4-ST131 E. coli showed few differences in terms of risk factors as well as similar outcome to non-ST131 E. coli. These data support the notion that ST131 strains are not less clinically virulent despite showing increased antimicrobial resistance, but also that they are not more virulent than other clonal groups causing BSI. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Clinical and molecular epidemiology of Escherichia coli sequence type 131 among hospitalized patients colonized intestinally with fluoroquinolone-resistant E. coli.

PubMed

Han, Jennifer H; Johnston, Brian; Nachamkin, Irving; Tolomeo, Pam; Bilker, Warren B; Mao, Xiangqun; Clabots, Connie; Lautenbach, Ebbing; Johnson, James R

2014-11-01

This study examined molecular and epidemiologic factors associated with Escherichia coli sequence type 131 (ST131) among hospitalized patients colonized intestinally with fluoroquinolone (FQ)-resistant E. coli between 2002 and 2004. Among 86 patients, 21 (24%) were colonized with ST131. The proportion of ST131 isolates among colonizing isolates increased significantly over time, from 8% in 2002 to 50% in 2004 (P = 0.003). Furthermore, all 19 clonally related isolates were ST131. Future studies should identify potential transmissibility differences between ST131 and non-ST131 strains. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Characterization of biofilms produced by Escherichia coli O157 isolated from cattle hides

NASA Astrophysics Data System (ADS)

Milojević, L.; Velebit, B.; Baltić, T.; Nikolić, A.; Mitrović, R.; Đorđević, V.

2017-09-01

This study aimed to investigate possibility E. coli O157 from cattle hides to produced biofilms. We had 28 suspect primoisolates and 17 were confirmed to be E. coli O157. Biofilm production test showed that more than 50% of this isolates did not produce biofilm. From the other half of the isolates, 5 of them were weakly adherent, 3 were moderately adherent. Since E. coli O157 are one of the main foodborne hazards in meat processing industry and the discovery that some of them can produce moderately adherent biofilms, request necessity of strict implementation of HACCP procedures to prevent further expansion this pathogen.

Virulence factors and antimicrobial resistance in Escherichia coli strains isolated from hen egg shells.

PubMed

Grande Burgos, María José; Fernández Márquez, Maria Luisa; Pérez Pulido, Rubén; Gálvez, Antonio; Lucas López, Rosario

2016-12-05

Eggs may contain extraintestinal pathogenic (ExPEC) and diarrheogenic (DEC) Escherichia coli which in addition may carry antibiotic resistance. The wide use of biocides and disinfectants in the food industry may induce biocide tolerance in bacteria. The aim of the present study was to evaluate biocide tolerance and antibiotic resistance in E. coli from hen egg shells. A total of 27 isolates obtained from a screening of 180 eggs were studied. Seven isolates carried both eae and bfpA genes of typical enteropathogenic E. coli (EPEC) strains, while 14 isolates only carried eae associated with atypical EPEC strains. Shiga toxin genes stx and stx2 were detected in four isolates. Heat-stable and heat-labile enterotoxin genes as well as aggR were also detected. Several isolates had minimum inhibitory concentrations (MICs) that were higher than the wild-type for the biocide hexadecylpyridinium chloride (HDP, 18.52%) or the commercial disinfectant P3 oxonia (OX, 14.81%). Antibiotic resistance was detected for ampicillin (37.03%), streptomycin (37.03%), tetracycline (37.03%), chloramphenicol (11.11%), nalidixic acid (18.51%) and trimethoprim-sulfamethoxazole (14.81%). Eight isolates (29.63%) were biocide tolerant and antibiotic resistant. Efflux pump genes detected included acrB (96.29%), mdfA (85.18%) and oxqA (37.03%), in addition to quaternary ammonium compound (QAC) resistance genes qacA/B (11.11%) and qacE (7.40%). Antibiotic resistance genes detected included bla CTX-M-2 (22.22%), bla TEM (3.70%), bla PSE (3.70%), tet(A) (29.63%), tet(B) (29.63%), tet(C) (7.40%), tet(E) (11.11%), aac(6')-Ib (3.70%), sul1 (14.81%), dfrA12 (3.70%) and dfrA15 (3.70%). Most isolates (96.30%) carried more than one genetic determinant of resistance. The most frequent combinations were efflux pump components acrB and mdfA with tetracycline resistance genes (33.33% of isolates). Isolates carrying QAC resistance genes also carried between 4 and 8 of the additional antimicrobial resistance genes investigated. Regardless of biocide tolerance and antibiotic resistance, all isolates were sensitive to carvacrol (0.25%), thymol (0.125%) and trisodium phosphate (1 to 1.5%), but they exhibited a heterogeneous response to sodium lactate and lysozyme-EDTA combinations that apparently were not related with antibiotic resistance. Results from the study reveal not only a low incidence of biocide tolerance but also the presence of multiple resistance strains carrying multiple genetic determinants of resistance. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification, cloning and sequencing of Escherichia coli strain chi1378 (O78:K80) iss gene isolated from poultry colibacillosis in Iran.

PubMed

Derakhshandeh, A; Zahraei Salehi, T; Tadjbakhsh, H; Karimi, V

2009-09-01

To identify, clone and sequence the iss (increased serum survival) gene from E. coli strain chi1378 isolated from Iranian poultry and to predict its protein product, Iss. The iss gene from E. coli strain chi1378 was amplified and cloned into the pTZ57R/T vector and sequenced. From the DNA sequence, the Iss predictive protein was evaluated using bioinformatics. Iss from strain chi1378 had 100% identity with other E. coli serotypes and isolates from different origins and also 98% identity with E. coli O157:H7 Iss protein. Phylogenetic analysis showed no significant different phylogenic groups among E. coli strains. The strong association of predicted Iss protein among different E. coli strains suggests that it could be a good antigen to control and detect avian pathogenic E. coli (APEC). Because the exact pathogenesis and the role of virulence factors are unknown, the Iss protein could be used as a target for vaccination in the future, but further research is required.

Slugs: potential novel vectors of Escherichia coli O157.

PubMed

Sproston, Emma L; Macrae, M; Ogden, Iain D; Wilson, Michael J; Strachan, Norval J C

2006-01-01

Field and laboratory studies were performed to determine whether slugs could act as novel vectors for pathogen (e.g., Escherichia coli O157) transfer from animal feces to salad vegetables. Escherichia coli O157 was isolated from 0.21% of field slugs from an Aberdeenshire sheep farm. These isolates carried the verocytotoxin genes (vt1 and vt2) and the attaching and effacing gene (eae), suggesting that they are potentially pathogenic to humans. Strain typing using multilocus variable number tandem repeats analysis showed that slug and sheep isolates were indistinguishable. Laboratory experiments using an E. coli mutant resistant to nalidixic acid showed that the ubiquitous slug species Deroceras reticulatum could carry viable E. coli on its external surface for up to 14 days. Slugs that had been fed E. coli shed viable bacteria in their feces with numbers showing a short but statistically significant linear log decline. Further, it was found that E. coli persisted for up to 3 weeks in excreted slug feces, and hence, we conclude that slugs have the potential to act as novel vectors of E. coli O157.

Slugs: Potential Novel Vectors of Escherichia coli O157

PubMed Central

Sproston, Emma L.; Macrae, M.; Ogden, Iain D.; Wilson, Michael J.; Strachan, Norval J. C.

2006-01-01

Field and laboratory studies were performed to determine whether slugs could act as novel vectors for pathogen (e.g., Escherichia coli O157) transfer from animal feces to salad vegetables. Escherichia coli O157 was isolated from 0.21% of field slugs from an Aberdeenshire sheep farm. These isolates carried the verocytotoxin genes (vt1 and vt2) and the attaching and effacing gene (eae), suggesting that they are potentially pathogenic to humans. Strain typing using multilocus variable number tandem repeats analysis showed that slug and sheep isolates were indistinguishable. Laboratory experiments using an E. coli mutant resistant to nalidixic acid showed that the ubiquitous slug species Deroceras reticulatum could carry viable E. coli on its external surface for up to 14 days. Slugs that had been fed E. coli shed viable bacteria in their feces with numbers showing a short but statistically significant linear log decline. Further, it was found that E. coli persisted for up to 3 weeks in excreted slug feces, and hence, we conclude that slugs have the potential to act as novel vectors of E. coli O157. PMID:16391036

Occurrence of Extended Spectrum β-Lactamases, KPC-Type, and MCR-1.2-Producing Enterobacteriaceae from Wells, River Water, and Wastewater Treatment Plants in Oltrepò Pavese Area, Northern Italy

PubMed Central

Caltagirone, Mariasofia; Nucleo, Elisabetta; Spalla, Melissa; Zara, Francesca; Novazzi, Federica; Marchetti, Vittoria M.; Piazza, Aurora; Bitar, Ibrahim; De Cicco, Marica; Paolucci, Stefania; Pilla, Giorgio; Migliavacca, Roberta; Pagani, Laura

2017-01-01

To evaluate the water compartment antibiotic-resistance contamination rates, 11 wells, five streams, and four treatment plants located in the Oltrepò Pavese area were screened for the presence of third generation cephalosporins resistant Gram-negative bacteria. Enterobacteriaceae were also characterized for the Extended-Spectrum-β-Lactamases (ESBLs), carbapenemases, and mcr-1 genes presence. From December 2014 to November 2015, 246 water samples were filtered, plated on Plate Count Agar, MacConkey Agar, and MacConkey Agar with cefotaxime. Isolates were species identified using AutoSCAN-4-System and ESBLs, carbapenemases, and colistin resistance determinants were characterized by PCR, sequencing, and microarray. Plasmid conjugative transfer experiments, PCR-based Replicon typing, Pulsed-Field Gel Electrophoresis, Multi-Locus-Sequence-Typing, and in-silico plasmid characterization were performed. A total of 132 enterobacteria isolates grew on MacConkey agar with cefotaxime: 82 (62.1%) were obtained from streams, 41 (31.1%) from treatment plants, and 9 (6.8%) from wells. Thirty out of 132 (22.7%) isolates, mainly belonging to Escherichia coli (n = 15) species, showed a synergic effect with piperacillin-tazobactam. A single ESBL gene of blaCTX−M-type was identified in 19/30 isolates. In further two E. coli strains, a blaCTX−M−1 gene co-existed with a blaSHV-type ESBL determinant. A blaSHV−12 gene was detected in two isolates of E. coli (n = 1) and Klebsiella oxytoca (n = 1), while any ESBL determinant was ascertained in seven Yersinia enterocolitica strains. A blaDHA-type gene was detected in a cefoxitin resistant Y. enterocolitica from a stream. Interestingly, two Klebsiella pneumoniae strains of ST307 and ST258, collected from a well and a wastewater treatment plant, resulted KPC-2, and KPC-3 producers, respectively. Moreover, we report the first detection of mcr-1.2 ST10 E. coli on a conjugative IncX4 plasmid (33.303 bp in size) from a stream of Oltrepò Pavese (Northern Italy). Both ESBLs E. coli and ESBLs/carbapenemase-producing K. pneumoniae strains showed clonal heterogeneity by Pulsed-Field Gel Electrophoresis and Multi-Locus-Sequence-Typing. During one-year study and taking in account the whole Gram-negative bacterial population, an average percentage of cefotaxime resistance of 69, 32, and 10.3% has been obtained for the wastewater treatment plants, streams, and wells, respectively. These results, of concern for public health, highlight the need to improve hygienic measures to reduce the load of discharged bacteria with emerging resistance mechanisms. PMID:29176971

Role of K1 capsule antigen in cirrhotic patients with Escherichia coli spontaneous bacterial peritonitis in southern Taiwan.

PubMed

Wang, M C; Lin, W H; Tseng, C C; Wu, A B; Teng, C H; Yan, J J; Wu, J J

2013-03-01

Spontaneous bacterial peritonitis (SBP) is one of the most serious complications in patients with cirrhosis. This study aimed to investigate the prevalence of SBP caused by Escherichia coli isolates with or without the K1 capsule antigen in cirrhotic patients and the outcome. From January 2004 to January 2012, a total of 54 and 41 E. coli strains derived from patients with SBP and intestinal perforation (IP), respectively, were included for comparison in this study. Bacterial characteristics including phylogenetic groups, K1 capsule antigen, and 14 virulence factor genetic determinants, as well as data regarding patient characteristics, clinical manifestations, and in-hospital deaths, were collected and analyzed. The prevalence of the K1 capsule antigen gene neuA was more common in SBP isolates compared to IP isolates (28 % vs. 10 %, p = 0.0385). Phylogenetic groups B2 and group D were dominant in E. coli isolates with and without the K1 capsule antigen, respectively. The prevalence of virulence factors genes papG II, ompT, and usp was higher in E. coli K1 strains. There were 26 deaths (48 %) during hospitalization. Presence of the K1 capsule antigen in E. coli isolates was significantly associated with in-hospital death in cirrhotic patients with SBP (42 % vs. 14 %, p = 0.0331). This study demonstrates a higher prevalence of the K1 capsule antigen in E. coli SBP compared to E. coli peritonitis caused by IP. There were significant associations between the K1 capsule antigen and in-hospital mortality and bacterial virulence in cirrhotic patients with E. coli SBP.

[Characterization of ibeB gene of meningitic Escherichia coli strains in calves from Xinjiang].

PubMed

Ling, Chen; Jiang, Jianjun; Song, Kang; Zhang, Kun; Shi, Yanxia; Feng, Guangyu; Ni, Hongbin; Zhu, Ling; Wang, Pengyan; Yan, Genqiang

2016-06-04

To understand the molecular biology information of ibeB gene of meningitic Escherichia coli isolates in calves. The strain used was isolated from the brain and liver tissue of calves died from Meningitis. It was identified to be an O161-K99-STa pathogenic Escherichia coli strain and named as bovine-EN and bovine-EG. Based on the sequence of ibeB gene of meningitic Escherichia coli K1 RS218 strain in GenBank, a pair of primers was designed and the ibeB gene was cloned from isolates by PCR. Part molecular biology information of ibeB among different strains was compared. The sequence length of isolates ibeB gene was 1500 bp, containing a 1371 bp open reading frame (ORF) encoding 457 amino acids. Bioinformatics analysis showed that the nucleotide and amino acid homology of ibeB gene of bovine-EN strain shared 90.5% and 96.9% identity with Escherichia coli K1 RS218 ibeB gene, respectively, while bovine-EG strain shared 99.4% and 100.0% identity with Escherichia coli K12 respectively. The ibeB gene of bovine-E strains encoded water-soluble protein whose molecular weight was 50.26 kDa and isoelectric point was 6.05. This protein contained a signal peptide A but no transmembrane domain. Subcellular localization of ibeB belonged to the secreted protein, which secretory signal path site (SP) proportion was 0.939. The ibeB gene was cloned from meningitic E. coli isolates and had higher homology and similar biological characteristics with meningitis E. coli K1 RS218ibeB, which belongs to extraintestinal pathogenic Escherichia coli.

Type 1 fimbrial expression enhances Escherichia coli virulence for the urinary tract.

PubMed

Connell, I; Agace, W; Klemm, P; Schembri, M; Mărild, S; Svanborg, C

1996-09-03

Type 1 fimbriae are adhesion organelles expressed by many Gram-negative bacteria. They facilitate adherence to mucosal surfaces and inflammatory cells in vitro, but their contribution to virulence has not been defined. This study presents evidence that type 1 fimbriae increase the virulence of Escherichia coli for the urinary tract by promoting bacterial persistence and enhancing the inflammatory response to infection. In a clinical study, we observed that disease severity was greater in children infected with E. coli O1:K1:H7 isolates expressing type 1 fimbriae than in those infected with type 1 negative isolates of the same serotype. The E. coli O1:K1:H7 isolates had the same electrophoretic type, were hemolysin-negative, expressed P fimbriae, and carried the fim DNA sequences. When tested in a mouse urinary tract infection model, the type 1-positive E. coli O1:K1:H7 isolates survived in higher numbers, and induced a greater neutrophil influx into the urine, than O1:K1:H7 type 1-negative isolates. To confirm a role of type 1 fimbriae, a fimH null mutant (CN1016) was constructed from an O1:K1:H7 type 1-positive parent. E. coli CN1016 had reduced survival and inflammatogenicity in the mouse urinary tract infection model. E. coli CN1016 reconstituted with type 1 fimbriae (E. coli CN1018) had restored virulence similar to that of the wild-type parent strain. These results show that type 1 fimbriae in the genetic background of a uropathogenic strain contribute to the pathogenesis of E. coli in the urinary tract.

Occurrence, genotyping, shiga toxin genes and associated risk factors of E. coli isolated from dairy farms, handlers and milk consumers.

PubMed

Awadallah, M A; Ahmed, H A; Merwad, A M; Selim, M A

2016-11-01

The objectives of the current study were to determine the occurrence and genotypes of E. coli in dairy farms, workers and milk consumers and to evaluate risk factors associated with contamination of milk in dairy farms. Molecular characterization of shiga toxin associated genes and enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) finger printing of E. coli from different sources were also studied. Paired milk samples and rectal swabs from 125 dairy cows, rectal swabs from 82 calves and hand swabs from 45 dairy workers from five dairy farms were collected. In addition, 100 stool samples from 70 diarrheic and 30 healthy humans were collected and examined for the presence of E. coli. E. coli was isolated from milk (22.4%), dairy cattle feces (33.6%), calf feces (35.4%), dairy worker hand swabs (11.1%) and stools of milk consumers (2%, from diarrheic patients only). Only stx1 was identified in seven of 12 E. coli O125 isolated from different sources. High genetic diversity was determined (Simpson's index of diversity, D = 1) and E. coli O125 isolates were classified into 12 distinct profiles, E1-E12. The dendrogram analysis showed that two main clusters were generated. Mastitis in dairy cows was considered a risk factor associated with contamination of the produced milk with E. coli. The isolation of E. coli from rectal swabs of dairy cows and calves poses a zoonotic risk through consumption of unpasteurized contaminated dairy milk. Educational awareness should be developed to address risks related to consumption of raw milk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Resistance to non-quinolone antimicrobials in commensal Escherichia coli isolates from chickens treated orally with enrofloxacin.

PubMed

Jurado, Sonia; Medina, Alberto; de la Fuente, Ricardo; Ruiz-Santa-Quiteria, José A; Orden, José A

2015-11-01

The aim of the present study was evaluate how oral administration of enrofloxacin affected the frequency of resistance to different antimicrobials in commensal Escherichia coli isolates from healthy chickens. A further objective of this study was to characterize the mechanisms of resistance in these isolates. A trend towards increased resistance to enrofloxacin, doxycycline and amoxicillin of E. coli isolates from chickens after enrofloxacin administration was observed. The increase in the resistance to doxycycline and amoxicillin was probably due to a co-selection of tetracycline and β-lactam resistance genes by the administration of enrofloxacin. The detection of tetM was much higher than expected (50%), which indicates that this gene may play an important role in tetracycline resistance in E. coli from chickens.

Genetic Investigation of Beta-Lactam Associated Antibiotic Resistance Among Escherichia Coli Strains Isolated from Water Sources.

PubMed

Ranjbar, Reza; Sami, Mehrdad

2017-01-01

Antimicrobial resistance is an important factor threatening human health. It is widely accepted that antibiotic resistant bacteria such as Escherichia coli ( E. coli) released from humans and animals into the water sources, can introduce their resistance genes into the natural bacterial community. The aim of this study was to investigate the prevalence of bla TEM , bla CTX , bla SHV , bla OXA and bla VEB associated-antibiotic resistance among E. coli bacteria isolated from different water resources in Iran. The study contained all E. coli strains segregated from different surface water sources. The Kirby-Bauer method and combined discs method was determined in this study for testing antimicrobial susceptibility and strains that produced Extended-Spectrum Beta Lactamases (ESBL), respectively. DNA extraction kit was applied for genomic and plasmid DNA derivation. Finally the frequency of resistant genes including bla TEM , bla CTX , bla SHV , bla OXA and bla VEB in ESBL producing isolates were studied by PCR. One hundred E. coli strains were isolated and entered in the study. The highest antibiotic resistance was observed on clindamycin (96%). Moreover, 38.5% isolates were ESBL producers. The frequency of different ESBLs genes were 37%, 27%, 27%, and 25% for bla TEM , bla CTX , bla SHV , and bla OXA , respectively. The bla VEB wasn't found in any isolates. The study revealed a high prevalence of CTX-M, TEM, SHV and OXA genes among E. coli strains in surface water resources. In conclusion, these results raised a concern regarding the presence and distribution of these threatening factors in surface water sources and its subsequent outcomes.

Co-Occurrence of Plasmid-Mediated AmpC β-Lactamase Activity Among Klebsiella pneumoniae and Escherichia Coli

PubMed Central

Zorgani, Abdulaziz; Daw, Hiyam; Sufya, Najib; Bashein, Abdullah; Elahmer, Omar; Chouchani, Chedly

2017-01-01

Introduction: Extended-spectrum β-lactamases (ESBLs), including the AmpC type, are important mechanisms of resistance among Klebsiella pneumoniae and Escherichia coli isolates. Objective: The aim of the study was to investigate the occurrence of AmpC-type β-lactamase producers isolated from two hospitals in Tripoli, Libya. Methods: All clinical isolates (76 K. pneumoniae and 75 E. coli) collected over two years (2013-2014) were evaluated for susceptibility to a panel of antimicrobials and were analyzed phenotypically for the ESBL and AmpC phenotype using E-test and ESBL and AmpC screen disc test. Both ESBL and AmpC-positive isolates were then screened for the presence of genes encoding plasmid-mediated AmpC β-lactamases by polymerase chain reaction (PCR). Results: Of the K. pneumoniae and E. coli tested, 75% and 16% were resistant to gentamicin, 74% and 1.3% to imipenem, 71% and 12% to cefoxitin, 80% and 12% to cefepime, 69% and 22.6% to ciprofloxacin, respectively. None of the E. coli isolates were multidrug resistant compared with K. pneumoniae (65.8%). K. pneumoniae ESBL producers were significantly higher (85.5%) compared with (17.3%) E. coli isolates (P <0.0001, OR=4.93). Plasmid-mediated AmpC genes were detected in 7.9% of K. pneumoniae, and 4% E. coli isolates. There was low agreement between phenotypic and genotypic methods, phenotypic testing underestimated detection of AmpC enzyme and did not correlate well with molecular results. The gene encoding CMY enzyme was the most prevalent (66.6%) of AmpC positive isolates followed by MOX, DHA and EBC. Only one AmpC gene was detected in 5/9 isolates, i.e, blaCMY (n=3), bla MOX (n=1), blaDHA (n=1). However, co-occurrence of AmpC genes were evident in 3/9 isolates with the following distribution: bla CMY and blaEBC (n=1), and blaCMY and blaMOX (n=2). Neither blaFOX nor blaACC was detected in all tested isolates. All AmpC positive strains were resistant to cefoxitin and isolated from patients admitted to intensive care units. Conclusion: Further studies are needed for detection of other AmpC variant enzyme production among such isolates. Continued surveillance and judicious antibiotic usage together with the implementation of efficient infection control measures are absolutely required. PMID:29151996

Co-Occurrence of Plasmid-Mediated AmpC β-Lactamase Activity Among Klebsiella pneumoniae and Escherichia Coli.

PubMed

Zorgani, Abdulaziz; Daw, Hiyam; Sufya, Najib; Bashein, Abdullah; Elahmer, Omar; Chouchani, Chedly

2017-01-01

Extended-spectrum β-lactamases (ESBLs), including the AmpC type, are important mechanisms of resistance among Klebsiella pneumoniae and Escherichia coli isolates. The aim of the study was to investigate the occurrence of AmpC-type β-lactamase producers isolated from two hospitals in Tripoli, Libya. All clinical isolates (76 K. pneumoniae and 75 E. coli ) collected over two years (2013-2014) were evaluated for susceptibility to a panel of antimicrobials and were analyzed phenotypically for the ESBL and AmpC phenotype using E-test and ESBL and AmpC screen disc test. Both ESBL and AmpC-positive isolates were then screened for the presence of genes encoding plasmid-mediated AmpC β-lactamases by polymerase chain reaction (PCR). Of the K. pneumoniae and E. coli tested, 75% and 16% were resistant to gentamicin, 74% and 1.3% to imipenem, 71% and 12% to cefoxitin, 80% and 12% to cefepime, 69% and 22.6% to ciprofloxacin, respectively. None of the E. coli isolates were multidrug resistant compared with K. pneumoniae (65.8%). K. pneumoniae ESBL producers were significantly higher (85.5%) compared with (17.3%) E. coli isolates (P <0.0001, OR=4.93). Plasmid-mediated AmpC genes were detected in 7.9% of K. pneumoniae , and 4% E. coli isolates. There was low agreement between phenotypic and genotypic methods, phenotypic testing underestimated detection of AmpC enzyme and did not correlate well with molecular results. The gene encoding CMY enzyme was the most prevalent (66.6%) of AmpC positive isolates followed by MOX, DHA and EBC. Only one AmpC gene was detected in 5/9 isolates, i.e, bla CMY (n=3), bla MOX (n=1), bla DHA (n=1). However, co-occurrence of AmpC genes were evident in 3/9 isolates with the following distribution: bla CMY and bla EBC (n=1), and bla CMY and bla MOX (n=2). Neither bla FOX nor bla ACC was detected in all tested isolates. All AmpC positive strains were resistant to cefoxitin and isolated from patients admitted to intensive care units. Further studies are needed for detection of other AmpC variant enzyme production among such isolates. Continued surveillance and judicious antibiotic usage together with the implementation of efficient infection control measures are absolutely required.

Molecular and Phenotypic Characterization of Escherichia coli O26:H8 among Diarrheagenic E. coli O26 Strains Isolated in Brazil

PubMed Central

Piazza, Roxane M. F.; Delannoy, Sabine; Fach, Patrick; Saridakis, Halha O.; Pedroso, Margareth Z.; Rocha, Letícia B.; Gomes, Tânia A. T.; Vieira, Mônica A. M.; Beutin, Lothar

2013-01-01

Escherichia coli strains of serogroup O26 comprise two distinct groups of pathogens, characterized as enteropathogenic E. coli (EPEC) and enterohemorrhagic E. coli (EHEC). Among the several genes related to type III secretion system-secreted effector proteins, espK was found to be highly specific for EHEC O26:H11 and its stx-negative derivative strains isolated in European countries. E. coli O26 strains isolated in Brazil from infant diarrhea, foods, and the environment have consistently been shown to lack stx genes and are thus considered atypical EPEC. However, no further information related to their genetic background is known. Therefore, in this study, we aimed to discriminate and characterize these Brazilian O26 stx-negative strains by phenotypic, genetic, and biochemical approaches. Among 44 isolates confirmed to be O26 isolates, most displayed flagellar antigen H11 or H32. Out of the 13 nonmotile isolates, 2 tested positive for fliCH11, and 11 were fliCH8 positive. The identification of genetic markers showed that several O26:H11 and all O26:H8 strains tested positive for espK and could therefore be discriminated as EHEC derivatives. The presence of H8 among EHEC O26 and its stx-negative derivative isolates is described for the first time. The interaction of three isolates with polarized Caco-2 cells and with intestinal biopsy specimen fragments ex vivo confirmed the ability of the O26 strains analyzed to cause attaching-and-effacing (A/E) lesions. The O26:H32 strains, isolated mostly from meat, were considered nonvirulent. Knowledge of the virulence content of stx-negative O26 isolates within the same serotype helped to avoid misclassification of isolates, which certainly has important implications for public health surveillance. PMID:23974139

Relationship between lactobacilli and opportunistic bacterial pathogens associated with vaginitis.

PubMed

Razzak, Mohammad Sabri A; Al-Charrakh, Alaa H; Al-Greitty, Bara Hamid

2011-04-01

Vaginitis, is an infectious inflammation of the vaginal mucosa, which sometimes involves the vulva. The balance of the vaginal flora is maintained by the Lactobacilli and its protective and probiotic role in treating and preventing vaginal infection by producing antagonizing compounds which are regarded as safe for humans. The aim of this study was to evaluate the protective role of Lactobacilli against common bacterial opportunistic pathogens in vaginitis and study the effects of some antibiotics on Lactobacilli isolates. In this study (110) vaginal swabs were obtained from women suffering from vaginitis who admitted to Babylon Hospital of Maternity and Paediatrics in Babylon province, Iraq. The study involved the role of intrauterine device among married women with vaginitis and also involved isolation of opportunistic bacterial isolates among pregnant and non pregnant women. This study also involved studying probiotic role of Lactobacilli by production of some defense factors like hydrogen peroxide, bacteriocin, and lactic acid. Results revealed that a total of 130 bacterial isolates were obtained. Intrauterine device was a predisposing factor for vaginitis. The most common opportunistic bacterial isolates were Staphylococcus aureus, Escherichia coli, Streptococcus agalactiae, and Klebsiella pneumoniae. All Lactobacilli were hydrogen peroxide producers while some isolates were bacteriocin producers that inhibited some of opportunistic pathogens (S. aureus, E. coli). Lactobacilli were sensitive to erythromycin while 93.3% of them were resistant to ciprofloxacin and (40%, 53.3%) of them were resistant to amoxicillin and gentamycin respectively. Results revealed that there was an inverse relationship between Lactobacilli presence and organisms causing vaginitis. This may be attributed to the production of defense factors by Lactobacilli. The types of antibiotics used to treat vaginitis must be very selective in order not to kill the beneficial bacteria (Lactobacilli) that help in preservation of vaginal health and ecosystem as being one of the probiotic bacteria.

EFFECT OF VISIBLE RANGE ELECTROMAGNETIC RADIATIONS ON ESCHERICHIA COLI.

PubMed

Azeemi, Samina T Yousuf; Shaukat, Saleem Farooq; Azeemi, Khawaja Shamsuddin; Khan, Idrees; Mahmood, Khalid; Naz, Farah

2017-01-01

Escherichia coli is the agent responsible for a range of clinical diseases. With emerging antimicrobial resistance, other treatment options including solar/photo-therapy are becoming increasingly common. Visible Range Radiation Therapy/Colour Therapy is an emerging technique in the field of energy/vibrational medicine that uses visible spectrum of Electromagnetic Radiations to cure different diseases. In this study, our goal was to understand the effect of Visible Range Electromagnetic Radiations on E. coli (in vitro) and therefore find out the most appropriate visible range radiation for the treatment of diseases caused by E. coli. A total of 6 non-repetitive E. coli isolates were obtained from urine samples obtained from hospitalized patients with UTI. Single colony of E. coli was inoculated in 3 ml of Lysogeny Broth (LB) and 40 μl of this E. coli suspension was poured into each of the plastic tubes which were then irradiated with six different wavelengths in the visible region (Table. 1) after 18 hours with one acting as a control. The Optical Densities of these irradiated samples were then measured. Furthermore, scanning electron microscopy (TEFCAN ZEGA3) was carried out. The analysis of the microscopic and SEM images of irradiated E. coli samples with six different visible range radiations is representative of The fact that E. coli responded differently to every applied radiation in the visible region and the most profound inhibitory effects were that of 538nm Visible Range Radiation (Green) which proved to be bactericidal and 590nm Visible Range Radiation (yellow) which was bacteriostatic. The enhanced growth of E. coli with varying degrees was clearly observed in 610nm (orange), 644nm (red), 464nm (Purple) and 453nm (blue). It can be concluded that 538nm (Green) and 590nm (Yellow) can effectively be used for treating E. coli borne diseases.

EFFECT OF VISIBLE RANGE ELECTROMAGNETIC RADIATIONS ON ESCHERICHIA COLI

PubMed Central

Azeemi, Samina T. Yousuf; Shaukat, Saleem Farooq; Azeemi, Khawaja Shamsuddin; Khan, Idrees; Mahmood, Khalid; Naz, Farah

2017-01-01

Background: Escherichia coli is the agent responsible for a range of clinical diseases. With emerging antimicrobial resistance, other treatment options including solar/photo-therapy are becoming increasingly common. Visible Range Radiation Therapy/Colour Therapy is an emerging technique in the field of energy/vibrational medicine that uses visible spectrum of Electromagnetic Radiations to cure different diseases. In this study, our goal was to understand the effect of Visible Range Electromagnetic Radiations on E. coli (in vitro) and therefore find out the most appropriate visible range radiation for the treatment of diseases caused by E. coli. Materials and Methods: A total of 6 non-repetitive E. coli isolates were obtained from urine samples obtained from hospitalized patients with UTI. Single colony of E. coli was inoculated in 3 ml of Lysogeny Broth (LB) and 40 μl of this E. coli suspension was poured into each of the plastic tubes which were then irradiated with six different wavelengths in the visible region (Table. 1) after 18 hours with one acting as a control. The Optical Densities of these irradiated samples were then measured. Furthermore, scanning electron microscopy (TEFCAN ZEGA3) was carried out. Results: The analysis of the microscopic and SEM images of irradiated E. coli samples with six different visible range radiations is representative of The fact that E. coli responded differently to every applied radiation in the visible region and the most profound inhibitory effects were that of 538nm Visible Range Radiation (Green) which proved to be bactericidal and 590nm Visible Range Radiation (yellow) which was bacteriostatic. The enhanced growth of E. coli with varying degrees was clearly observed in 610nm (orange), 644nm (red), 464nm (Purple) and 453nm (blue). Conclusion: It can be concluded that 538nm (Green) and 590nm (Yellow) can effectively be used for treating E. coli borne diseases. PMID:28331912

Feeding of waste milk to Holstein calves affects antimicrobial resistance of Escherichia coli and Pasteurella multocida isolated from fecal and nasal swabs.

PubMed

Maynou, G; Bach, A; Terré, M

2017-04-01

The use of milk containing antimicrobial residues in calf feeding programs has been shown to select for resistant fecal Escherichia coli in dairy calves. However, information is scarce about the effects of feeding calves waste milk (WM) on the prevalence of multidrug-resistant bacteria. The objective of this study was to determine the antimicrobial resistance patterns of fecal E. coli and nasal Pasteurella multocida isolates from calves fed either milk replacer (MR) or WM in 8 commercial dairy farms (4 farms per feeding program). Fecal and nasal swabs were collected from 20 ± 5 dairy calves at 42 ± 3.2 d of age, and from 10 of these at approximately 1 yr of age in each study farm to isolate the targeted bacteria. Furthermore, resistance of E. coli isolates from calf-environment and from 5 calves at birth and their dams was also evaluated in each study farm. Resistances were tested against the following antimicrobial agents: amoxicillin-clavulanic acid, ceftiofur, colistin, doxycycline (DO), enrofloxacin (ENR), erythromycin, florfenicol, imipenem, and streptomycin. A greater number of fecal E. coli resistant to ENR, florfenicol, and streptomycin and more multidrug-resistant E. coli phenotypes were isolated in feces of calves fed WM than in those fed MR. However, the prevalence of fecal-resistant E. coli was also influenced by calf age, as it increased from birth to 6 wk of age for ENR and DO and decreased from 6 wk to 1 yr of age for DO regardless of the feeding program. From nasal samples, an increase in the prevalence of colistin-resistant P. multocida was observed in calves fed WM compared with those fed MR. The resistance patterns of E. coli isolates from calves and their dams tended to differ, whereas similar resistance profiles among E. coli isolates from farm environment and calves were observed. The findings of this study suggest that feeding calves WM fosters the presence of resistant bacteria in the lower gut and respiratory tracts of dairy calves. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Evidence of Naturalized Stress-Tolerant Strains of Escherichia coli in Municipal Wastewater Treatment Plants

PubMed Central

Zhi, Shuai; Banting, Graham; Li, Qiaozhi; Edge, Thomas A.; Topp, Edward; Sokurenko, Mykola; Scott, Candis; Braithwaite, Shannon; Ruecker, Norma J.; Yasui, Yutaka; McAllister, Tim; Chui, Linda

2016-01-01

ABSTRACT Escherichia coli has been proposed to have two habitats—the intestines of mammals/birds and the nonhost environment. Our goal was to assess whether certain strains of E. coli have evolved toward adaptation and survival in wastewater. Raw sewage samples from different treatment plants were subjected to chlorine stress, and ∼59% of the surviving E. coli strains were found to contain a genetic insertion element (IS30) located within the uspC-flhDC intergenic region. The positional location of the IS30 element was not observed across a library of 845 E. coli isolates collected from various animal hosts or within GenBank or whole-genome reference databases for human and animal E. coli isolates (n = 1,177). Phylogenetics clustered the IS30 element-containing wastewater E. coli isolates into a distinct clade, and biomarker analysis revealed that these wastewater isolates contained a single nucleotide polymorphism (SNP) biomarker pattern that was specific for wastewater. These isolates belonged to phylogroup A, possessed generalized stress response (RpoS) activity, and carried the locus of heat resistance, features likely relevant to nonhost environmental survival. Isolates were screened for 28 virulence genes but carried only the fimH marker. Our data suggest that wastewater contains a naturalized resident population of E. coli. We developed an endpoint PCR targeting the IS30 element within the uspC-flhDC intergenic region, and all raw sewage samples (n = 21) were positive for this marker. Conversely, the prevalence of this marker in E. coli-positive surface and groundwater samples was low (≤5%). This simple PCR assay may represent a convenient microbial source-tracking tool for identification of water samples affected by municipal wastewater. IMPORTANCE The results of this study demonstrate that some strains of E. coli appear to have evolved to become naturalized populations in the wastewater environment and possess a number of stress-related genetic elements likely important for survival in this nonhost environment. The presence of non-host-adapted strains in wastewater challenges our understanding of using E. coli as a microbial indicator of wastewater treatment performance, suggesting that the E. coli strains present in human and animal feces may be very different from those found in treated wastewater. PMID:27371583

Uropathogenic Escherichia coli ST131 in urinary tract infections in children.

PubMed

Yun, Ki Wook; Lee, Mi-Kyung; Kim, Wonyong; Lim, In Seok

2017-07-01

Escherichia coli sequence type (ST) 131, a multidrug-resistant clone causing extraintestinal infections, has rapidly become prevalent worldwide. However, the epidemiological and clinical features of pediatric infections are poorly understood. We aimed to explore the characteristics of ST131 Escherichia coli isolated from Korean children with urinary tract infections. We examined 114 uropathogenic E. coli (UPEC) isolates from children hospitalized at Chung-Ang University Hospital between 2011 and 2014. Bacterial strains were classified into STs by partial sequencing of seven housekeeping genes ( adk , fumC , gyrB , icd , mdh , purA , and recA ). Clinical characteristics and antimicrobial susceptibility were compared between ST131 and non-ST131 UPEC isolates. Sixteen UPEC isolates (14.0%) were extended-spectrum β-lactamase (ESBL)-producers; 50.0% of ESBL-producers were ST131 isolates. Of all the isolates tested, 13.2% (15 of 114) were classified as ST131. There were no statistically significant associations between ST131 and age, sex, or clinical characteristics, including fever, white blood cell counts in urine and serum, C-reactive protein, radiologic abnormalities, and clinical outcome. However, ST131 isolates showed significantly lower rates of susceptibility to cefazolin (26.7%), cefotaxime (40.0%), cefepime (40.0%), and ciprofloxacin (53.3%) than non-ST131 isolates (65.7%, 91.9%, 92.9%, and 87.9%, respectively; P <0.001 for all). ESBL was more frequently produced in ST131 (53.3%) than in non-ST131 (8.1%) isolates ( P <0.01). ST131 E. coli isolates were prevalent uropathogens in children at a single medical center in Korea between 2011 and 2014. Although ST131 isolates showed higher rates of antimicrobial resistance, clinical presentation and outcomes of patients were similar to those of patients infected with non-ST131 isolates.

Frequency of antimicrobial resistance and integron gene cassettes in Escherichia coli isolated from giant pandas (Ailuropoda melanoleuca) in China.

PubMed

Zou, Wencheng; Li, Caiwu; Yang, Xin; Wang, Yongxiang; Cheng, Guangyang; Zeng, Jinxin; Zhang, Xiuzhong; Chen, Yanpeng; Cai, Run; Huang, Qianru; Feng, Lan; Wang, Hongning; Li, Desheng; Zhang, Guiquan; Chen, Yanxi; Zhang, Zhizhong; Zhang, Heming

2018-03-01

Escherichia coli (E. coli) is considered as a common opportunistic pathogen, which causes seriously intestinal infections to giant pandas (Ailuropoda melanoleuca) and other animals. The aim of this investigation was to characterize the antimicrobial resistance and integron gene cassettes in E. coli isolated from the faeces of giant pandas in China. A total of 89 E. coli were isolated, after diagnosis of isolates and genomes were extracted. All the isolates were screened for the presence of related drug-resistance genes and integron gene cassettes through the Polymerase Chain Reaction (PCR) and sequencing. In addition, antimicrobial resistance testing was performed according to the standard disk diffusion method (CLSI 2013). The results demonstrated that all the isolates were multi-drug resistance (MDR). High resistance proportions of the E. coli isolates were to streptomycin (93%), cefazolin (90%), amikacin (75%), tetracycline (65%), ampicillin (62%), cefotaxime and trimethoprim-sulfamethoxazole (54%, each). With respect to the various resistance genes; bla CTX-M , sul1, ant (3')-Ia, tetA, qnrB, tetE, floR, aac (6')-Ib, sul2, rmtA, cmlA, rmtB and tetC were identified with the respective frequencies of 44%, 45%, 38%, 37%, 35%, 27%, 26%, 20%, 18%, 15%, 10%, 7% and 4%. None of the isolates was positive for qnrA and cfr genes. Moreover, a further investigation of integron revealed that the emergence of class 1 and 2 integrons were in 47% and 8% isolates, respectively. While class 3 integron was not screened. Six types of containing in class 1 integron specific gene cassettes (dfrA12-orfF-aadA2, dfrA17-aadA5, aadA1, aadA5, dfrA1 and dfrA7) were identified. However, only one gene cassette (dfrA1-sat2-aadA1) was detected in class 2 integron. These finding emphasize that a high level of E. coli isolates harbored antibiotics resistance and integron gene cassettes, which may bring so many potential threats to the health of giant pandas. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Effect of Pseudomonas aeruginosa exometabolites on planktonic and biofilm cultures of Escherichia coli].

PubMed

Kuznetsova, M V; Karpunina, T I; Maslennikova, I L; Nesterova, L Iu; Demakov, V A

2012-01-01

Study the effect of P. aeruginosa exometabolites on planktonic and biofilm cultures of bioluminescent E. coli strain. E. coli K12 TG1 (pF1 lux+ Ap(r)) recombinant bioluminescent strain, P. aeruginosa ATCC 27853 reference strain and 2 nosocomial isolates were used. Pyocyanin and pyoverdin content in supernatant of P. aeruginosa over-night cultures was evaluated according to E. Deziel et al. (2001). Planktonic and biofilm cultures of E. coli were obtained in 96-well plates (LB, statically, 37 degrees C), optical density of plankton, film biomass (OD600, OD580) and bioluminescence in plankton and biofilm were evaluated in microplate reader Infiniti M200 (Tecan, Austria). P. aeruginosa exometabolites increased the duration of lag-phase in E. coli, and short term exposition inhibited luminescence of planktonic cells. These effects are determined by bactericidal action ofpyocyanin and pyoverdin. Supernatants ofover-night cultures of P. aeruginosa inhibit formation of biofilm and disrupt the formed biofilm of E. coli. Effect of pyocyanin and pyoverdin on these processes is not established, other factors may have higher significance. Bioluminescence of E. coli K12 TGI that reflects the energetic status of the cell allows to evaluate and prognose the character of coexistence of P. aeruginosa in combined with E. coli planktonic and biofilm culture.

Free water surface constructed wetlands limit the dissemination of extended-spectrum beta-lactamase producing Escherichia coli in the natural environment.

PubMed

Vivant, Anne-Laure; Boutin, Catherine; Prost-Boucle, Stéphanie; Papias, Sandrine; Hartmann, Alain; Depret, Géraldine; Ziebal, Christine; Le Roux, Sophie; Pourcher, Anne-Marie

2016-11-01

The fates of Escherichia coli and extended-spectrum beta-lactamase-producing E. coli (ESBL E. coli) were studied over a period of one year in a free water surface constructed wetland (FWS CW) with a succession of open water zones and vegetation ponds (Typha or Phragmites), that received the effluent from a wastewater treatment plant. ESBL E. coli were detected and isolated from all sampling areas of the FWS CW throughout the study period. They represented 1‰ of the total E. coli population regardless of the origin of samples. Two main factors affected the log removal of E. coli and of ESBL E. coli: the season and the presence of vegetation. Between the inlet and the outlet of the FWS CW, the log removal of E. coli ranged from 1.5 in the warmer season (summer and fall) to 3.0 in the colder season (winter and spring). The concentrations of E. coli decreased significantly in the vegetated areas during the colder season, but increased in the warmer season, suggesting an effect of the plant growth stage on the survival of E. coli. Among the 369 ESBL E. coli isolates collected during our study, 84% harbored the CTX-M-ESBL type and 55.3% carried bla genes on plasmid DNA. Furthermore, 93% of the ESBL E. coli isolates were multidrug resistant but the proportion of resistant strains did not change significantly along the FWS CW. ESBL E. coli were characterized by MLST analysis using the 7 genes based Achtman Scheme. ESBL E. coli isolated from water, sediments, roots and feces of myocastors collected in the FWS CW and in the recipient river were genotypically related, suggesting persistence and circulation of the ESBL producing E. coli throughout the FWS CW and in the receiving river. Overall, these observations show that FWS CW could be an efficient treatment for ESBL E. coli disinfection of wastewater and could limit their dissemination in the aquatic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Norwegian patients and retail chicken meat share cephalosporin-resistant Escherichia coli and IncK/blaCMY-2 resistance plasmids.

PubMed

Berg, E S; Wester, A L; Ahrenfeldt, J; Mo, S S; Slettemeås, J S; Steinbakk, M; Samuelsen, Ø; Grude, N; Simonsen, G S; Løhr, I H; Jørgensen, S B; Tofteland, S; Lund, O; Dahle, U R; Sunde, M

2017-06-01

In 2012 and 2014 the Norwegian monitoring programme for antimicrobial resistance in the veterinary and food production sectors (NORM-VET) showed that 124 of a total of 406 samples (31%) of Norwegian retail chicken meat were contaminated with extended-spectrum cephalosporin-resistant Escherichia coli. The aim of this study was to compare selected cephalosporin-resistant E. coli from humans and poultry to determine their genetic relatedness based on whole genome sequencing (WGS). Escherichia coli representing three prevalent cephalosporin-resistant multi-locus sequence types (STs) isolated from poultry (n=17) were selected from the NORM-VET strain collections. All strains carried an IncK plasmid with a bla CMY-2 gene. Clinical E. coli isolates (n=284) with AmpC-mediated resistance were collected at Norwegian microbiology laboratories from 2010 to 2014. PCR screening showed that 29 of the clinical isolates harboured both IncK and bla CMY-2 . All IncK/bla CMY-2 -positive isolates were analysed with WGS-based bioinformatics tools. Analysis of single nucleotide polymorphisms (SNP) in 2.5 Mbp of shared genome sequences showed close relationship, with fewer than 15 SNP differences between five clinical isolates from urinary tract infections (UTIs) and the ST38 isolates from poultry. Furthermore, all of the 29 clinical isolates harboured IncK/bla CMY-2 plasmid variants highly similar to the IncK/bla CMY-2 plasmid present in the poultry isolates. Our results provide support for the hypothesis that clonal transfer of cephalosporin-resistant E. coli from chicken meat to humans may occur, and may cause difficult-to-treat infections. Furthermore, these E. coli can be a source of AmpC-resistance plasmids for opportunistic pathogens in the human microbiota. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Antibiotic Resistance Characterization of Environmental E. coli Isolated from River Mula-Mutha, Pune District, India.

PubMed

Dhawde, Rutuja; Macaden, Ragini; Saranath, Dhananjaya; Nilgiriwala, Kayzad; Ghadge, Appasaheb; Birdi, Tannaz

2018-06-12

In the current study, ceftazidime- and ciprofloxacin-resistant—or dual drug-resistant (DDR)— E. coli were isolated from river Mula-Mutha, which flows through rural Pune district and Pune city. The DDR E. coli were further examined for antibiotic resistance to six additional antibiotics. The study also included detection of genes responsible for ceftazidime and ciprofloxacin resistance and vectors for horizontal gene transfer. Twenty-eight percent of the identified DDR E. coli were resistant to more than six antibiotics, with 12% being resistant to all eight antibiotics tested. Quinolone resistance was determined through the detection of qnrA , qnrB , qnrS and oqxA genes, whereas cephalosporin resistance was confirmed through detection of TEM, CTX-M-15, CTX-M-27 and SHV genes. Out of 219 DDR E. coli , 8.2% were qnrS positive and 0.4% were qnrB positive. Percentage of isolates positive for the TEM, CTX-M-15 and CTX-M-27 genes were 32%, 46% and 0.9%, respectively. None of the DDR E. coli tested carried the qnrA , SHV and oqxA genes. Percentage of DDR E. coli carrying Class 1 and 2 integrons (mobile genetic elements) were 47% and 8%, respectively. The results showed that antibiotic resistance genes (ARGs) and integrons were present in the E. coli isolated from the river at points adjoining and downstream of Pune city.

Microbiological quality of fresh produce obtained from retail stores on the Eastern Shore of Maryland, United States of America.

PubMed

Korir, Robert Cheruiyot; Parveen, Salina; Hashem, Fawzy; Bowers, John

2016-06-01

The aim of this study was to investigate the microbiological quality of six types of fresh produce obtained from three retail stores located on the Eastern Shore of Maryland, USA. A total of 414 samples representing basil, cilantro, lettuce, scallion, spinach, and parsley were analyzed for total aerobic bacteria (APC), total coliforms, Escherichia coli, and three pathogenic bacteria (E. coli O157:H7, Listeria monocytogenes, and Salmonella), using standard methods. Presumptive pathogenic isolates were confirmed using BAX Polymerase Chain Reaction. Total aerobic populations varied widely between samples, while 38.41% were positive for total coliforms and only 10.15% for E. coli. Median abundance (log CFU/g) of total coliforms and E. coli were less than the limit of detection and that of APC ranged from 5.78 to 6.61 over the six produce types. There was a statistically significant difference in prevalence of total coliforms among the retail stores, but not for abundance of APC or prevalence of E. coli. E. coli O157:H7 and L. monocytogenes were detected in one spinach sample each, while one parsley and one cilantro sample were positive for Salmonella. There were no statistically significant differences in microbiological quality among produce types. Although the results of this study provided some indices of sanitary and/or spoilage level, no relationship was observed among the total aerobic bacteria, total coliforms, E. coli, and the presence of pathogenic bacteria in the samples tested. Copyright © 2015 Elsevier Ltd. All rights reserved.

Escherichia coli isolates from commercial chicken meat and eggs cause sepsis, meningitis and urinary tract infection in rodent models of human infections.

PubMed

Mellata, M; Johnson, J R; Curtiss, R

2018-02-01

The zoonotic potential of Escherichia coli from chicken-source food products is important to define for public health purposes. Previously, genotypic and phenotypic screening of E. coli isolates from commercial chicken meat and shell eggs identified some E. coli strains that by molecular criteria resembled human-source extraintestinal pathogenic E. coli (ExPEC). Here, to clarify the zoonotic risk of such chicken-source E. coli, we compared selected E. coli isolates from chicken meat and eggs, stratified by molecularly defined ExPEC status, to human-source ExPEC and to laboratory E. coli for virulence in rodent models of sepsis, meningitis and UTI, and evaluated whether specific bacterial characteristics predict experimental virulence. Multiple chicken-source E. coli resembled human-source ExPEC in their ability to cause one or multiple different ExPEC-associated infections. Swimming ability corresponded with urovirulence, K1 capsule corresponded with ability to cause neonatal meningitis, and biofilm formation in urine corresponded with ability to cause sepsis. In contrast, molecularly defined ExPEC status and individual genotypic traits were uncorrelated with ability to cause sepsis, and neither complement sensitivity nor growth in human urine corresponded with virulence in any infection model. These findings establish that chicken-derived food products contain E. coli strains that, in rodent models of multiple human-associated ExPEC infections, are able to cause disease comparably to human-source E. coli clinical isolates, which suggests that they may pose a significant food safety threat. Further study is needed to define the level of risk they pose to human health, which if appreciable would justify efforts to monitor for and reduce or eliminate them. © 2017 Blackwell Verlag GmbH.

Antimicrobial resistance profiles of common mastitis pathogens on Canadian dairy farms.

PubMed

Saini, V; McClure, J T; Léger, D; Keefe, G P; Scholl, D T; Morck, D W; Barkema, H W

2012-08-01

Monitoring of antimicrobial resistance (AMR) in bacteria has clinical and public health significance. The present study determined prevalence of AMR in common mastitis pathogens Staphylococcus aureus, including methicillin-resistant Staph. aureus (MRSA; n=1,810), Escherichia coli (n=394), and Klebsiella species (n=139), including extended-spectrum β-lactamase (ESBL)-producing E. coli and Klebsiella species, isolated from milk samples on 89 dairy farms in 6 Canadian provinces. Minimum inhibitory concentrations (MIC) were determined using the Sensititer bovine mastitis plate (Trek Diagnostic Systems Inc., Cleveland, OH) and a National Antimicrobial Resistance Monitoring System gram-negative panel containing antimicrobials commonly used for mastitis treatment and control. Denim blue chromogenic agar and real-time PCR were used to screen and confirm MRSA, respectively. Resistance proportion estimates ranged from 0% for cephalothin and oxacillin to 8.8% for penicillin in Staph. aureus isolates, and 15% of the resistant Staph. aureus isolates were multidrug resistant. One MRSA isolate was confirmed (prevalence: 0.05%). Resistance proportion estimates ranged from 0% for ceftriaxone and ciprofloxacin to 14.8% for tetracycline in E. coli, and 0% for amikacin, ceftiofur, ciprofloxacin, and nalidixic acid to 18.6% for tetracycline in Klebsiella species isolates. Further, 62.8 and 55% of the resistant E. coli and Klebsiella species isolates were multidrug resistant, respectively. Resistance to >5 and >2 antimicrobials was most common in E. coli and Klebsiella species isolates, respectively, and no ESBL producers were found. Prevalence of AMR in bovine mastitis pathogens was low. Most gram-negative udder pathogens were multidrug resistant; MRSA was rarely found, and ESBL E. coli and Klebsiella species isolates were absent in Canadian milk samples. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada

PubMed Central

Boulianne, Martine; Arsenault, Julie; Daignault, Danielle; Archambault, Marie; Letellier, Ann; Dutil, Lucie

2016-01-01

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry. PMID:26733732

Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada.

PubMed

Boulianne, Martine; Arsenault, Julie; Daignault, Danielle; Archambault, Marie; Letellier, Ann; Dutil, Lucie

2016-01-01

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.

Draft genome sequence analysis of multidrug-resistant Escherichia coli strains isolated in 2013 from humans and chickens in Nigeria

USDA-ARS?s Scientific Manuscript database

Here, we present the draft genome sequences of nine multidrug-resistant Escherichia coli isolated from humans (n=6) and chicken carcass (n=3) from Lagos, Nigeria in 2013. Multiple extended-spectrum beta-lactamase (ESBL) genes were identified in these isolates. ...

Fecal carriage of extended-spectrum β-lactamases and AmpC-producing Escherichia coli in a Libyan community

PubMed Central

2014-01-01

Background Extended-spectrum β-lactamases (ESBLs), including the AmpC type, are important mechanisms of resistance among Enterobacteriaeceae. CTX-M type extended-spectrum β- lactamases, of which there are now over 90 variants, are distributed globally, yet appear to vary in regional distribution. AmpC β-lactamases hydrolyze third generation cephalosporins, but are resistant to inhibition by clavulanate or other β-lactamase inhibitors in vitro. Fecal carriage and rates of colonization by bacteria harboring these resistance mechanisms have been reported in patients with community-acquired infections and in healthy members of their households. Expression of these ESBLs compromises the efficacy of current antibacterial therapies, potentially increasing the seriousness of hospital- and community-acquired Escherichia coli (E. coli) infections. To investigate the occurrence of ESBL-producing E. coli in human fecal flora isolated from two pediatric populations residing in the Libyan cities Zleiten and Abou El Khoms. Isolates were further studied to characterize genes encoding β-lactam resistance, and establish genetic relationships. Methods Antibiotic resistance profiles of phenotypically characterized E. coli isolates recovered from the stools of 243 Libyan children during two surveillance periods in 2001 and 2007 were determined by the disk diffusion method. ESBL-screening was performed using the cephalosporin/clavulanate double synergy disc method, and the AmpC-phenotype was confirmed by the aminophenyl-boronic acid test. ESBL genes were molecularly characterized. Phylogenetic group and multilocus sequence typing (MLST) were determined for ESBL-producing isolates and PFGE was performed to compare banding profiles of some dominant strains. Results ESBLs were identified in 13.4% (18/134) of E. coli isolates, and nine isolates (6.7%) demonstrated AmpC activity; all 18 isolates contained a CTX-M gene. Three CTX-M gene families (CTX-M-1, n = 9; CTX-M-15, n = 8 and CTX-M-3, n = 1) were distributed in diverse E. coli backgrounds (phylogenetic group D, 39%; B2, 28%; B1, 22% and A, 11%). MLST analysis revealed 14 sequence type (ST) with six new sequence types. The gene encoding the CMY-2 enzyme was detected in five AmpC-positive E. coli. Conclusions These results identified heterogeneous clones of CTX-M-producing E. coli in the fecal isolates, indicating that the intestinal tract acts as a reservoir for ESBL-producing organisms, and a trafficker of antibiotic resistance genes. PMID:24934873

Symbiotic Fungus of Marine Sponge Axinella sp. Producing Antibacterial Agent

NASA Astrophysics Data System (ADS)

Trianto, A.; Widyaningsih, S.; Radjasa, OK; Pribadi, R.

2017-02-01

The emerging of multidrug resistance pathogenic bacteria cause the treatment of the diseaseshave become ineffective. There for, invention of a new drug with novel mode of action is an essential for curing the disease caused by an MDR pathogen. Marine fungi is prolific source of bioactive compound that has not been well explored. This study aim to obtain the marine sponges-associated fungus that producing anti-MDR bacteria substaces. We collected the sponge from Riung water, NTT, Indonesia. The fungus was isolated with affixed method, followed with purification with streak method. The overlay and disk diffusion agar methods were applied for bioactivity test for the isolate and the extract, respectively. Molecular analysis was employed for identification of the isolate. The sponge was identified based on morphological and spicular analysis. The ovelay test showed that the isolate KN15-3 active against the MDR Staphylococcus aureus and Eschericia coli. The extract of the cultured KN15-3 was also inhibited the S. aureus and E. coli with inhibition zone 2.95 mm and 4.13 mm, respectively. Based on the molecular analysis, the fungus was identified as Aspergillus sydowii. While the sponge was identified as Axinella sp.

Increased Amoxicillin–Clavulanic Acid Resistance in Escherichia coli Blood Isolates, Spain

PubMed Central

Oteo, Jesús; Lázaro, Edurne; Cuevas, Óscar; García-Cobos, Silvia; Pérez-Vázquez, María; de Abajo, F. J.

2008-01-01

To determine the evolution and trends of amoxicillin–clavulanic acid resistance among Escherichia coli isolates in Spain, we tested 9,090 blood isolates from 42 Spanish hospitals and compared resistance with trends in outpatient consumption. These isolates were collected by Spanish hospitals that participated in the European Antimicrobial Resistance Surveillance System network from April 2003 through December 2006. PMID:18680650

Antimicrobial resistance in diarrheagenic Escherichia coli from ready-to-eat foods.

PubMed

Lima, Cíntia Matos; Souza, Ingrid Evelyn Gomes Lima; Dos Santos Alves, Taila; Leite, Clícia Capibaribe; Evangelista-Barreto, Norma Suely; de Castro Almeida, Rogeria Comastri

2017-10-01

Certain subgroups of Escherichia coli have congenital or acquired virulence properties that allow them to cause a wide spectrum of disease. The aim of this study was to investigate the occurrence of diarrheagenic E. coli strains in ready-to-eat (RTE) foods produced in institutional, commercial and hotel restaurants in Salvador, Brazil. The presence of virulent isolates and antimicrobial resistance were evaluated. Four hundred forty-six samples were collected and grouped into cereals and vegetables, meat-based preparations, cooked salads, raw salads, garnishes, soups and sauces, desserts and juices. E. coli were detected using the most probable number method, the presence of virulence factors in isolates was determined by polymerase chain reaction (PCR) assays, and antibiotic resistance was analyzed using the disc diffusion method. In total, 15 isolates (3.1%) of E. coli were recovered; raw salads had the highest detection rate, 1.4%, followed by cooked salads, 0.8%; meat-based preparations, 0.4%; and cereals and vegetables, 0.4%. PCR assays showed that none of the isolates had the virulence genes cnf1, cnf2, eae , sta, lt1, stx1, stx2 or cdtB . The isolates showed resistance to nine antibiotics of the 15 tested, and the highest levels of resistance were found for sulfamethoxazole/trimethoprim, tetracycline, ampicillin, and chloramphenicol (13.3% of isolates for each antibiotic). One isolate from cooked salad had plasmid-mediated multidrug resistance to tetracycline, trimethoprim/sulfamethoxazole, ampicillin and chloramphenicol. These results suggest that RTE foods, especially raw salads, can be reservoirs of E. coli and facilitate the spread of antibiotic resistance genes to the gastrointestinal microbiota of humans.

Poultry hatcheries as potential reservoirs for antimicrobial-resistant Escherichia coli: A risk to public health and food safety.

PubMed

Osman, Kamelia M; Kappell, Anthony D; Elhadidy, Mohamed; ElMougy, Fatma; El-Ghany, Wafaa A Abd; Orabi, Ahmed; Mubarak, Aymen S; Dawoud, Turki M; Hemeg, Hassan A; Moussa, Ihab M I; Hessain, Ashgan M; Yousef, Hend M Y

2018-04-11

Hatcheries have the power to spread antimicrobial resistant (AMR) pathogens through the poultry value chain because of their central position in the poultry production chain. Currently, no information is available about the presence of AMR Escherichia coli strains and the antibiotic resistance genes (ARGs) they harbor within hatchezries. Therefore, this study aimed to investigate the possible involvement of hatcheries in harboring hemolytic AMR E. coli. Serotyping of the 65 isolated hemolytic E. coli revealed 15 serotypes with the ability to produce moderate biofilms, and shared susceptibility to cephradine and fosfomycin and resistance to spectinomycin. The most common β-lactam resistance gene was bla TEM , followed by bla OXA-1 , bla MOX -like , bla CIT -like , bla SHV and bla FOX . Hierarchical clustering of E. coli isolates based on their phenotypic and genotypic profiles revealed separation of the majority of isolates from hatchlings and the hatchery environments, suggesting that hatchling and environmental isolates may have different origins. The high frequency of β-lactam resistance genes in AMR E. coli from chick hatchlings indicates that hatcheries may be a reservoir of AMR E. coli and can be a major contributor to the increased environmental burden of ARGs posing an eminent threat to poultry and human health.

Molecular Characterization of Plasmids Encoding CTX-M β-Lactamases and their Associated Addiction Systems Circulating Among Escherichia coli from Retail Chickens, Chicken Farms, and Slaughterhouses in Korea.

PubMed

Jo, Su-Jin; Woo, Gun-Jo

2016-02-01

Extended-spectrum β-lactamases (ESBLs), particularly those of the CTX-M types, are the predominant resistance determinants of Escherichia coli that are rapidly spreading worldwide. To determine CTX-M types, E. coli isolates were collected from retail chickens (n = 390) and environmental samples from chicken farms (n = 32) and slaughterhouses (n = 67) in Korea. Fifteen strains harboring blaCTX-M genes were isolated from 358 E. coli isolates. The most common CTX-M type was eight of CTX-M-15, followed by six of CTX-M-1 and one of CTX-M- 14. The blaCTX-M genes were identified in the isolates from retail chickens (n = 9), followed by feces, water pipes, floors, and walls. Conjugations confirmed the transferability of the plasmids carrying blaCTX-M genes to the recipient E. coli J53 strain. Furthermore, eight addiction systems carried by the replicons in CTX-M types were confirmed. The dominant system was identified as ccdAB, vagCD, and pndAC in donor strains and transconjugants. The clonal relationship between the two strains carrying blaCTX-M genes indicates that E. coli may transmit from the farm to retail chickens, suggesting a possible public health risk. Our findings demonstrate that the detection of CTX-M types in E. coli isolates is important for tracking ESBL production in animals, and suggest linkage of multiple addiction systems in plasmids bearing blaCTX-M genes.

Whole Genome Sequencing demonstrates that Geographic Variation of Escherichia coli O157 Genotypes Dominates Host Association.

PubMed

Strachan, Norval J C; Rotariu, Ovidiu; Lopes, Bruno; MacRae, Marion; Fairley, Susan; Laing, Chad; Gannon, Victor; Allison, Lesley J; Hanson, Mary F; Dallman, Tim; Ashton, Philip; Franz, Eelco; van Hoek, Angela H A M; French, Nigel P; George, Tessy; Biggs, Patrick J; Forbes, Ken J

2015-10-07

Genetic variation in an infectious disease pathogen can be driven by ecological niche dissimilarities arising from different host species and different geographical locations. Whole genome sequencing was used to compare E. coli O157 isolates from host reservoirs (cattle and sheep) from Scotland and to compare genetic variation of isolates (human, animal, environmental/food) obtained from Scotland, New Zealand, Netherlands, Canada and the USA. Nei's genetic distance calculated from core genome single nucleotide polymorphisms (SNPs) demonstrated that the animal isolates were from the same population. Investigation of the Shiga toxin bacteriophage and their insertion sites (SBI typing) revealed that cattle and sheep isolates had statistically indistinguishable rarefaction profiles, diversity and genotypes. In contrast, isolates from different countries exhibited significant differences in Nei's genetic distance and SBI typing. Hence, after successful international transmission, which has occurred on multiple occasions, local genetic variation occurs, resulting in a global patchwork of continental and trans-continental phylogeographic clades. These findings are important for three reasons: first, understanding transmission and evolution of infectious diseases associated with multiple host reservoirs and multi-geographic locations; second, highlighting the relevance of the sheep reservoir when considering farm based interventions; and third, improving our understanding of why human disease incidence varies across the world.

Label-free isolation and deposition of single bacterial cells from heterogeneous samples for clonal culturing

NASA Astrophysics Data System (ADS)

Riba, J.; Gleichmann, T.; Zimmermann, S.; Zengerle, R.; Koltay, P.

2016-09-01

The isolation and analysis of single prokaryotic cells down to 1 μm and less in size poses a special challenge and requires micro-engineered devices to handle volumes in the picoliter to nanoliter range. Here, an advanced Single-Cell Printer (SCP) was applied for automated and label-free isolation and deposition of bacterial cells encapsulated in 35 pl droplets by inkjet-like printing. To achieve this, dispenser chips to generate micro droplets have been fabricated with nozzles 20 μm in size. Further, the magnification of the optical system used for cell detection was increased. Redesign of the optical path allows for collision-free addressing of any flat substrate since no compartment protrudes below the nozzle of the dispenser chip anymore. The improved system allows for deterministic isolation of individual bacterial cells. A single-cell printing efficiency of 93% was obtained as shown by printing fluorescent labeled E. coli. A 96-well plate filled with growth medium is inoculated with single bacteria cells on average within about 8 min. Finally, individual bacterial cells from a heterogeneous sample of E. coli and E. faecalis were isolated for clonal culturing directly on agar plates in user-defined array geometry.

Antimicrobial resistance in Escherichia coli and Salmonella spp. isolates from fresh produce and the impact to food safety.

PubMed

Vital, Pierangeli G; Caballes, Marie Bernadine D; Rivera, Windell L

2017-09-02

Foodborne diseases associated with fresh produce consumption have escalated worldwide, causing microbial safety of produce of critical importance. Bacteria that have increasingly been detected in fresh produce are Escherichia coli and Salmonella spp., both of which have been shown to progressively display antimicrobial resistance. The study focused on the assessment of antimicrobial resistance of these enteric bacteria from different kinds of fresh produce from various open air markets and supermarkets in the Philippines. Using the disk diffusion assay on a total of 50 bacterial isolates obtained from 410 fresh produce surveyed, monoresistance to tetracycline was observed to be the most prevalent (38%), followed by multidrug resistance to tetracycline, chloramphenicol, ciprofloxacin, and nalidixic acid (4%), and lastly by dual resistance to tetracycline and chloramphenicol (2%). Using multiplex and simplex polymerase chain reaction (PCR) assays, tetA (75%) and tetB (9%) were found in tetracycline resistant isolates, whereas catI (67%) and catIII (33%) were detected in chloramphenicol resistant isolates. Sequence analysis of gyr and par genes from the ciprofloxacin and nalidixic acid resistant isolates revealed different mutations. Based on the results, fresh produce act as a reservoir of these antibiotic resistant bacteria which may pose health threat to consumers.

MOLECULAR CHARACTERISATION AND ANTIMICROBIAL RESISTANCE PATTERNS OF ESCHERICHIA COLI ISOLATES FROM GOATS SLAUGHTERED IN PARTS OF KENYA.

PubMed

Njoroge, S; Muigai, A W T; Njiruh, P N; Kariuki, S

2013-03-01

To determine the antibiotic resistance patterns of pathogenic Escherichia coli on goat meat carcass at Huruma and Kiserian abattoirs in Kenya. Laboratory based study. Huruma and Kiserian abattoirs in Kenya, 400 slaughtered goats inspected by veterinary health officers and approved for human consumption. A Total of 400 slaughtered goats which were inspected by veterinary health officers and approved for human consumption were sampled from Huruma and Kiserian abattoir. Goat carcass swabs were collected by passing each swab tissue on four parts of the carcass mainly neck, right and left forelimbs, right and left hind limbs, and brisket. A total of 54 E. coli isolates were isolated and confirmed to be pathogenic. The percentage of isolates resistant to various microbial agents was recorded as follows: ampicillin (26 %), amoxycillin-clavulanic acid (17%), tetracycline (15%), chroramphenicol (4%), and ceftrixone (2% each). All Escherichia coli isolates were susceptible to gentamicin sulphamethaxazole-trimethomprin, kanamycin, cetriazididine (CAZ, 30pg), ciproxacin, nalidixic acid and chloramphenicol. Isolates were resistant to one or more of the antibiotics tested. Among the drugs tested, resistance was more frequently observed against ampicillin, amoxycillin-clavulanic acid, tetracycline, ceftrixone and chroramphenicol antibiotics. Among the isolates 26(48%) were positive for the stx1 gene, 19(35%) had the eae gene, 10(19%) possessed est gene,while 8(15%) harboured elt gene. Overall five isolates (10%) possessed aspu gene and two (4%) had aggR gene. No isolate possessed ipah gene. This study demonstrated that there is a significant level of antimicrobial resistance in pathogenic E. coli isolated from goat meat from Huruma and Kiserian abattoir. This indicates that goat meat from abattoirs could pose a risk of transmission of pathogenic antibiotic resistant strains to human. Poor hygienic standards and indiscriminate use of antimicrobials are the two main reasons for the presence of resistant pathogens in goat carcasses. Implemention of appropriate hygiene measures to control contamination of meat with pathogenic E. coli.

Analyzing indicator microorganisms, antibiotic resistant Escherichia coli, and regrowth potential of foodborne pathogens in various organic fertilizers.

PubMed

Miller, Cortney; Heringa, Spencer; Kim, Jinkyung; Jiang, Xiuping

2013-06-01

This study analyzed various organic fertilizers for indicator microorganisms, pathogens, and antibiotic-resistant Escherichia coli, and evaluated the growth potential of E. coli O157:H7 and Salmonella in fertilizers. A microbiological survey was conducted on 103 organic fertilizers from across the United States. Moisture content ranged from approximately 1% to 86.4%, and the average pH was 7.77. The total aerobic mesophiles ranged from approximately 3 to 9 log colony-forming units (CFU)/g. Enterobacteriaceae populations were in the range of <1 to approximately 7 log CFU/g, while coliform levels varied from <1 to approximately 6 log CFU/g. Thirty samples (29%) were positive for E. coli, with levels reaching approximately 6 log CFU/g. There were no confirmed positives for E. coli O157:H7, Salmonella, or Listeria monocytogenes. The majority of E. coli isolates (n=73), confirmed by glutamate decarboxylase (gad) PCR, were from group B1 (48%) and group A (32%). Resistance to 16 antibiotics was examined for 73 E. coli isolates, with 11 isolates having resistance to at least one antibiotic, 5 isolates to ≥ 2 antibiotics, and 2 isolates to ≥ 10 antibiotics. In the presence of high levels of background aerobic mesophiles, Salmonella and E. coli O157:H7 grew approximately 1 log CFU/g within 1 day of incubation in plant-based compost and fish emulsion-based compost, respectively. With low levels of background aerobic mesophiles, Salmonella grew approximately 2.6, 3.0, 3.0, and 3.2 log CFU/g in blood, bone, and feather meals and the mixed-source fertilizer, respectively, whereas E. coli O157:H7 grew approximately 4.6, 4.0, 4.0, and 4.8 log CFU/g, respectively. Our results revealed that the microbiological quality of organic fertilizers varies greatly, with some fertilizers containing antibiotic resistant E. coli and a few supporting the growth of foodborne pathogens after reintroduction into the fertilizer.

Differential Distribution of Type II CRISPR-Cas Systems in Agricultural and Nonagricultural Campylobacter coli and Campylobacter jejuni Isolates Correlates with Lack of Shared Environments.

PubMed

Pearson, Bruce M; Louwen, Rogier; van Baarlen, Peter; van Vliet, Arnoud H M

2015-09-02

CRISPR (clustered regularly interspaced palindromic repeats)-Cas (CRISPR-associated) systems are sequence-specific adaptive defenses against phages and plasmids which are widespread in prokaryotes. Here we have studied whether phylogenetic relatedness or sharing of environmental niches affects the distribution and dissemination of Type II CRISPR-Cas systems, first in 132 bacterial genomes from 15 phylogenetic classes, ranging from Proteobacteria to Actinobacteria. There was clustering of distinct Type II CRISPR-Cas systems in phylogenetically distinct genera with varying G+C%, which share environmental niches. The distribution of CRISPR-Cas within a genus was studied using a large collection of genome sequences of the closely related Campylobacter species Campylobacter jejuni (N = 3,746) and Campylobacter coli (N = 486). The Cas gene cas9 and CRISPR-repeat are almost universally present in C. jejuni genomes (98.0% positive) but relatively rare in C. coli genomes (9.6% positive). Campylobacter jejuni and agricultural C. coli isolates share the C. jejuni CRISPR-Cas system, which is closely related to, but distinct from the C. coli CRISPR-Cas system found in C. coli isolates from nonagricultural sources. Analysis of the genomic position of CRISPR-Cas insertion suggests that the C. jejuni-type CRISPR-Cas has been transferred to agricultural C. coli. Conversely, the absence of the C. coli-type CRISPR-Cas in agricultural C. coli isolates may be due to these isolates not sharing the same environmental niche, and may be affected by farm hygiene and biosecurity practices in the agricultural sector. Finally, many CRISPR spacer alleles were linked with specific multilocus sequence types, suggesting that these can assist molecular epidemiology applications for C. jejuni and C. coli. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Potentially pathogenic Escherichia coli in healthy, pasture-raised sheep on farms and at the abattoir in Brazil.

PubMed

Maluta, Renato Pariz; Fairbrother, John Morris; Stella, Ariel Eurides; Rigobelo, Everlon Cid; Martinez, Roberto; de Ávila, Fernando Antonio

2014-02-21

Sheep harbor pathogenic Escherichia coli, which may cause severe disease in humans. In this study, the prevalence of Shiga toxin-producing E. coli (STEC) and enteropathogenic E. coli (EPEC) was examined in sheep feces and carcasses on three farms and at an abattoir in Brazil. The isolates were further characterized for the presence of markers recently associated with disease in humans, to investigate their possible origin and role as food-borne pathogens. At the abattoir, 99 carcass samples yielded two STEC and 10 EPEC isolates while 101 fecal samples yielded five EPEC and eight STEC isolates. On the other hand, on the farms, 202 samples yielded 44 STEC and eight EPEC isolates. The 77 isolates were typed by PFGE. Isolates with the same PFGE pattern and also those that were not restricted with XbaI were termed as "clones" (n=49). The isolates of any one clone mostly originated from the same sampling site. In addition, seven isolates encoded for novel Stx2 variants and five for Stx2e, the subtype related to porcine edema disease, which was for the first time isolated from sheep feces and carcasses. Also, three stx2-only isolates harbored genes of predicted Stx2 variants that were formed by A and B subunits of different types including Stx2a and Stx2d. The EPEC isolates were heterogeneous, 21 (91.3%) of them possessing efa1, ehxA, lpfAO113 or paa genes associated with diarrhea in humans. Thus, using markers recently associated with disease, we have demonstrated that E. coli similar to those pathogenic for humans are present in the sheep intestinal microflora, particularly at the abattoir, underlining the potential for food-borne transmission. Copyright © 2013 Elsevier B.V. All rights reserved.

Prevalence and Molecular Characterization of Plasmid-mediated Extended-Spectrum β-Lactamase Genes (balaTEM, blaCTX and blASHV) Among Urinary Escherichia coli Clinical Isolates in Mashhad, Iran

PubMed Central

Nakhaei Moghaddam, Mahboobeh; Forghanifard, Mohammad Mahdi; Moshrefi, Sheila

2012-01-01

Objective(s) Extended-spectrum beta-lactamase (ESBL) producing bacteria have an important role in nosocomial infections. Due to the limited availability of information about the molecular epidemiology of ESBL producing bacteria in Mashhad, we decided to investigate about TEM, CTX and SHV ESBLs among urinary Escherichia coli isolates in Mashhad, a city in northeast Iran. Materials and Methods One hundred and eleven clinical isolates of E. coli were diagnosed from hospitalized patients in 2009. After performing antibiogram and phenotypic confirmation test, polymerase chain reaction (PCR) was performed by blaTEM, blaSHV and blaCTX primers and restriction digestion was carried out using PstI and TaqI (Fermentas-Lithuania) for confirmation. Results ESBL producers of E. coli isolates were 33.3%. Among 37 ESBL-producing isolates, 35 (94.6%), 21 (56.8%) and 5 (13.5%) were shown to have blaCTX, blaTEM and blaSHV, genes respectively. Co-resistance to non-beta lactam antibiotics was observed more with ESBL producers (P < 0.05). Conclusion The results showed that the studied ESBL genes are found with high prevalence and among them blaCTX is more widespread in urine E. coli isolates in Mashhad. PMID:23493415

A comparison of inpatient versus outpatient resistance patterns of pediatric urinary tract infection.

PubMed

Saperston, Kara N; Shapiro, Daniel J; Hersh, Adam L; Copp, Hillary L

2014-05-01

Prior single center studies showed that antibiotic resistance patterns differ between outpatients and inpatients. We compared antibiotic resistance patterns for urinary tract infection between outpatients and inpatients on a national level. We examined outpatient and inpatient urinary isolates from children younger than 18 years using The Surveillance Network (Eurofins Scientific, Luxembourg, Luxembourg), a database of antibiotic susceptibility results, as well as patient demographic data from 195 American hospitals. We determined the prevalence and antibiotic resistance patterns of the 6 most common uropathogens, including Escherichia coli, Proteus mirabilis, Klebsiella, Enterobacter, Pseudomonas aeruginosa and Enterococcus. We compared differences in uropathogen prevalence and resistance patterns for outpatient and inpatient isolates using chi-square analysis. We identified 25,418 outpatient (86% female) and 5,560 inpatient (63% female) urinary isolates. Escherichia coli was the most common uropathogen overall but its prevalence varied by gender and visit setting, that is 79% of uropathogens overall for outpatient isolates, including 83% of females and 50% of males, compared to 54% for overall inpatient isolates, including 64% of females and 37% of males (p <0.001). Uropathogen resistance to many antibiotics was lower in the outpatient vs inpatient setting, including trimethoprim/sulfamethoxazole 24% vs 30% and cephalothin 16% vs 22% for E. coli (each p <0.001), cephalothin 7% vs 14% for Klebsiella (p = 0.03), ceftriaxone 12% vs 24% and ceftazidime 15% vs 33% for Enterobacter (each p <0.001), and ampicillin 3% vs 13% and ciprofloxacin 5% vs 12% for Enterococcus (each p <0.001). Uropathogen resistance rates of several antibiotics are higher for urinary specimens obtained from inpatients vs outpatients. Separate outpatient vs inpatient based antibiograms can aid in empirical prescribing for pediatric urinary tract infections. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Virulence factors and antimicrobial susceptibility profile of extraintestinal Escherichia coli isolated from an avian colisepticemia outbreak.

PubMed

Maciel, Jonas Fernandes; Matter, Letícia Beatriz; Trindade, Michele Martins; Camillo, Giovana; Lovato, Maristela; de Ávila Botton, Sônia; Castagna de Vargas, Agueda

2017-02-01

In this study an avian colisepticemia outbreak was investigated. Two isolates from a chicken with colisepticemia were characterized for antimicrobial susceptibility and virulence factors profile. For this purpose 7 antimicrobial and 29 genes (fimH, hrlA/hek, iha, papC, sfa/focCD, tsh, mat, tia, gimB, ibeA, chuA, fyuA, ireA, iroN, irp2, iucD, sitD. chr., sitD. ep., iss, neuC, ompA, traT, astA, hlyA, sat, vat, pic, malX, cvi/cva) were tested. The outbreak happened in a hick chicken breeding located in the northwestern region of Rio Grande do Sul state in South of Brazil and caused 28.3% (102 deads of a total of 360 chickens) of mortality rate. Escherichia coli isolates obtained from the avian spleen and liver belong to the same phylogenetic group A and present resistance to all antimicrobials tested (ampicillin, tetracycline, gentamicin, neomycin, sulfa + trimethoprim, enrofloxacin, and norfloxacin). Both isolates harbor virulence factors related to adhesion (fimH, papC, mat), invasion (tia), iron acquisition system (iroN) and serum resistance (iss, ompA, traT), showing that these groups are important for Avian Pathogenic E. coli (APEC). However, they present different virulence profiles for some genes, whereas liver-isolate carries more hrlA/hek (adhesin), gimB (invasin), sitD ep. (iron acquisition system), sat (toxin) and hylA (toxin) genes, the spleen-isolate harbors fyuA (iron acquisition system) gene. Here, we highlight a coinfection by different strains of APEC in the same animal with colisepticemia, the great antimicrobial resistance of these bacterial isolates and the genetic traits that modulate the virulence for high mortality rate of chickens for human consumption. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reduction of Carriage of Enterohemorrhagic Escherichia coli O157:H7 in Cattle by Inoculation with Probiotic Bacteria

PubMed Central

Zhao, Tong; Doyle, Michael P.; Harmon, Barry G.; Brown, Cathy A.; Mueller, P. O. Eric; Parks, Andrew H.

1998-01-01

Bacteria inhibitory to Escherichia coli O157:H7 were isolated from cattle and evaluated for their potential for reducing carriage of E. coli O157:H7 in calves. Eighteen of 1,200 bacterial isolates from cattle feces and intestinal tissue samples were screened and determined to inhibit the growth of E. coli O157:H7 in vitro. Seventeen of the isolates were E. coli and one was Proteus mirabilis. None produced Shiga toxin. Genomic DNA fingerprinting by pulsed-field gel electrophoresis revealed 13 distinguishable profiles among the 18 isolates. Two calves inoculated perorally with a mixture of all 18 isolates (1010 CFU) appeared to be normal and did not develop signs of clinical disease throughout a 25- to 27-day observation period. These bacteria colonized segments of the gastrointestinal tract and were in feces at the termination of the experiment (25 and 27 days postinoculation) at levels of 50 to 200 CFU/g. Fifteen cannulated calves were studied to determine the efficiency of the probiotic bacteria in reducing or eliminating the carriage of E. coli O157:H7. Nine calves served as controls, with each animal receiving perorally 1010 CFU of E. coli O157:H7. E. coli O157:H7 was detected intermittently in the rumen samples from all control animals throughout 3 weeks postinoculation, whereas E. coli O157:H7 was shed at various levels in feces continuously throughout the experiment (mean, 28 days). E. coli O157:H7 was isolated from the rumens and colons of eight of nine and nine of nine calves, respectively, at the termination of the study. Six calves each received perorally 1010 CFU of probiotic bacteria and then 2 days later received 1010 CFU of E. coli O157:H7. E. coli O157:H7 was detected in the rumen for only 9 days postinoculation in two animals, for 16 days in one animal, for 17 days in two animals, and for 29 days in one animal. E. coli O157:H7 was detected in feces for only 11 days postinoculation in one animal, for 15 days in one animal, for 17 days in one animal, for 18 days in one animal, for 19 days in one animal, and for 29 days in one animal. At the end of the experiment (mean, 30 days), E. coli O157:H7 was not recovered from the rumen of any of the six animals treated with probiotic bacteria; however, E. coli O157:H7 was recovered from the feces of one of the animals. This animal was fasted twice postinoculation. These studies indicate that selected probiotic bacteria administered to cattle prior to exposure to E. coli O157:H7 can reduce the level of carriage of E. coli O157:H7 in most animals. PMID:9508288

Plasmid-mediated AmpC beta-lactamase-producing Escherichia coli causing urinary tract infection in the Auckland community likely to be resistant to commonly prescribed antimicrobials.

PubMed

Drinkovic, Dragana; Morris, Arthur J; Dyet, Kristin; Bakker, Sarah; Heffernan, Helen

2015-03-13

To estimate the prevalence and characterise plasmid-mediated AmpC beta-lactamase (PMACBL)- producing Escherichia coli in the Auckland community. All cefoxitin non-susceptible (NS) E. coli identified at the two Auckland community laboratories between 1 January and 31 August 2011 were referred to ESR for boronic acid double-disc synergy testing, to detect the production of AmpC beta-lactamase, and polymerase chain reaction (PCR) to identify the presence of PMACBL genes. PMACBL-producing isolates were typed using pulsed-field gel electrophoresis (PFGE), and PCR was used to determine their phylogenetic group and to identify multilocus sequence type (ST)131. Antimicrobial susceptibility testing and detection of extended-spectrum beta-lactamases (ESBLs) were performed according to the Clinical and Laboratory Standards Institute recommendations. 101 (51%) and 74 (37%) of 200 non-duplicate cefoxitin-NS E. coli were PMACBL producers or assumed hyper-producers of chromosomal AmpC beta-lactamase, respectively. The prevalence of PMACBL-producing E. coli was 0.4%. PMACBL-producing E. coli were significantly less susceptible to norfloxacin, trimethoprim and nitrofurantoin than E. coli that produced neither a PMACBL nor an ESBL. Very few (4%) PMACBL-producing E. coli co-produced an ESBL. Most (88%) of the PMACBL-producing isolates had a CMY-2-like PMACBL. The PMACBL-producing E. coli isolates were diverse based on their PFGE profiles, 44% belonged to phylogenetic group D, and only four were ST131. 100 of the 101 PMACBL-producing E. coli were cultured from urine, and were causing urinary tract infection (UTI) in the majority of patients. The median patient age was 56 years and most (94%) of the patients were women. A greater proportion of patients with community-acquired UTI caused by PMACBL-producing E. coli received a beta-lactam antimicrobial than patients with community-acquired UTI caused by other non-AmpC, non-ESBL-producing E. coli. Thirty-six (43%) patients with community-acquired UTI due to PMACBL-producing E. coli were neither hospitalised nor had any antimicrobial treatment in the previous 6 months. The prevalence of PMACBL-producing E. coli was relatively low in the Auckland community, but has increased in recent years. Typing revealed that the majority of the PMACBL-producing E. coli in the Auckland region were genetically unrelated meaning that a point source or direct person to person transmission are not drivers of local community spread currently. The isolates were more resistant to non-beta-lactam antimicrobials than other non-AmpC, non-ESBL-producing E. coli, leaving few treatment options. The majority of the PMACBL-producing E. coli isolates seemed to be acquired in the community and were most frequently isolated from women with UTI. A large proportion of patients with community-acquired UTI had not been hospitalised nor had any antimicrobial treatment in the previous 6 months.

High prevalence of multidrug-resistant Escherichia coli isolates from children with and without diarrhoea and their susceptibility to the antibacterial activity of extracts/fractions of fruits native to Mexico.

PubMed

Uribe-Beltrán, Magdalena de Jesús; Ahumada-Santos, Yesmi Patricia; Díaz-Camacho, Sylvia Páz; Eslava-Campos, Carlos Alberto; Reyes-Valenzuela, Jesús Ernesto; Báez-Flores, María Elena; Osuna-Ramírez, Ignacio; Delgado-Vargas, Francisco

2017-07-01

This paper aims to evaluate the antimicrobial resistance of Esherichia coli isolates from children under 5 years old, with and without diarrhoea, who were hospital outpatients in Culiacan, Sinaloa, Mexico. It also looks at the antimicrobial activity of fruit extracts against selected multidrug-resistant (MDR) E. coli strains. A total of 205 E. coli isolates from stool samples were collected from 94 children under 5 years old who were outpatients from two hospitals in the city of Culiacan, Sinaloa, Mexico, during the autumn/winter of 2003/04; their resistance profiles to 19 commercial antimicrobials were investigated using the Kirby-Bauer method. The antibacterial activities of extracts/fractions of fruits (i.e. uvalama, Vitex mollis; ayale, Crescentia alata; and arrayan, Psidium sartorianum) were evaluated using the broth microdilution method. All E. coli isolates were susceptible to amikacin, nitrofurantoin and meropenem, and approximately 96 % were resistant to at least one antimicrobial, especially carbenicillin (93.2 %), cefuroxime sodium (53.7 %), ampicillin (40 %) and trimethoprim/sulfamethoxazole (35.1 %). Likewise, the frequency of MDR strains (44.9 %) was high, and no significant association with diarrhoea symptoms was found. Remarkably, all fruit extracts/fractions showed antibacterial activity against some, but not all, MDR isolates. The lowest minimal inhibitory concentration values were for the hexane fraction of arrayan (0.25 mg ml-1). A high number of antimicrobial-resistant E. coli (especially to β-lactams and sulfonamides) and MDR isolates were detected in children under 5 years old, irrespective of diarrhoea symptoms; this is novel information for Culiacan, Sinaloa, Mexico. Moreover, our results showed that the studied fruit extracts/fractions are potential alternative or complementary treatments for MDR E. coli strains.

Mequindox resistance and in vitro efficacy in animal-derived Escherichia coli strains.

PubMed

He, Tao; Wang, Yang; Qian, Minyi; Wu, Congming

2015-06-12

This study investigated the in vitro efficacy of mequindox against enteropathogenic Escherichia coli (EPEC), and characterized the oqxAB genes as the main mequindox resistance determinant in E. coli strains of animal origin. A total of 1123 E. coli isolates were collected from domestic animals in China from the 1970s to 2013, and mequindox susceptibility was tested by broth microdilution. The percentage of E. coli isolates with increased mequindox MICs of ≥ 64 μg/ml showed a rising trend each year throughout the study period. Mequindox showed good bactericidal activity in vitro towards 20 EPEC strains, although it had a wide mutant selection window. All 1123 E. coli isolates were tested for the presence of the oqxAB genes, and the operon was detected in 322 isolates, which accounted for 94.4% (322/341) of isolates with increased MICs to mequindox (MIC ≥ 64 μg/ml). Of the isolates with mequindox MIC ≤ 32 μg/ml, 98.8% (773/782) were oqxAB negative. Polymerase chain reaction-based stability testing revealed that the IS26-oqxAB circular intermediate was present in 93.4% (309/331) of the oqxAB-positive strains, indicating that this IS26-flanked Tn6010 element was unstable and prone to excision via IS26-mediated recombination. Functional analysis of the oqxAB genes confirmed that this operon alone is sufficient to confer resistance or increased MICs to multiple antimicrobials, including mequindox. This is the first study to investigate the relationship between mequindox susceptibility and oqxAB genotype, and may provide the basis for establishing the resistance breakpoint for mequindox against E. coli. Copyright © 2015 Elsevier B.V. All rights reserved.

Lactobacillus acidophilus INMIA 9602 Er-2 strain 317/402 probiotic regulates growth of commensal Escherichia coli in gut microbiota of familial Mediterranean fever disease subjects.

PubMed

Pepoyan, A Z; Balayan, M H; Manvelyan, A M; Mamikonyan, V; Isajanyan, M; Tsaturyan, V V; Kamiya, S; Netrebov, V; Chikindas, M L

2017-04-01

Previously, we reported a positive effect the probiotic formulation, Lactobacillus acidophilus INMIA 9602 Er-2 strain 317/402 (Narine strain), had on the blood characteristics of patients with familial Mediterranean fever disease (FMF). The aim of this investigation was to evaluate the effect of the Narine probiotic on growth characteristics in the predominant commensal Escherichia coli isolates from the gut microbiota in FMF-positive study participants. Bacterial growth of 192 prevalent commensal E. coli isolates found in the volunteer participants' guts was evaluated using Verhulst's logistic function. This study showed that the duration of the preparatory growth phase for the E. coli isolates collected from FMF-positive volunteers was significantly shorter, whereas the duration of the logarithmic growth phase was significantly longer (P < 0·03) than that of the isolates collected from healthy participants. The Narine probiotic formulation caused a significant extension (P < 0·001) of the preparatory growth phase in the commensal E. coli isolated from FMF subjects a month after the Narine probiotic administration was terminated. The data suggest that the mathematical model characterizes the growth of commensal E. coli isolates from FMF-positive participants and it can be useful in a decision-making process on the practical use of probiotics during FMF. This is the first study to demonstrate the effects of Narine, containing the probiotic Lactobacillus acidophilus, on the growth of gut commensal Escherichia coli from study participants with familial Mediterranean fever disease (FMF). Verhulst's logistic function was demonstrated to act as a possible tool for the evaluation and quantification of effects produced by the probiotic formulation in FMF participants. © 2017 The Society for Applied Microbiology.

Detection of acrA, acrB, aac(6')-Ib-cr, and qepA genes among clinical isolates of Escherichia coli and Klebsiella pneumoniae.

PubMed

Heidary, Mohsen; Bahramian, Aghil; Hashemi, Ali; Goudarzi, Mehdi; Omrani, Vahid Fallah; Eslami, Gita; Goudarzi, Hossein

2017-03-01

The distribution of drug resistance among clinical isolates of Escherichia coli and Klebsiella pneumoniae has limited the therapeutic options. The aim of this study was to report the prevalence of quinolone resistance genes among E. coli and K. pneumoniae clinical strains isolated from three educational hospitals of Tehran, Iran. A total of 100 strains of E. coli from Labbafinejad and Taleghani Hospitals and 100 strains of K. pneumoniae from Mofid Children and Taleghani Hospitals were collected between January 2013 and May 2014. Antimicrobial susceptibility tests were done by disk diffusion method based on Clinical and Laboratory Standards Institute guidelines. Detection of qepA, aac(6')-Ib-cr, acrA, and acrB genes was done by polymerase chain reaction (PCR). In this study, fosfomycin and imipenem against E. coli and fosfomycin and tigecycline against K. pneumoniae had the best effect in antimicrobial susceptibility tests. PCR assay using specific primers demonstrated that the prevalence of qepA, aac(6')-Ib-cr, acrA, and acrB genes among the 100 E. coli isolates was 0 (0%), 87 (87%), 92 (92%), and 84 (84%), respectively. The prevalence of qepA, aac(6')-Ib-cr, acrA, and acrB genes among the 100 K. pneumoniae isolates was 4 (4%), 85 (85%), 94 (94%), and 87 (87%), respectively. The distribution of qepA, aac(6')-Ib-cr, acrA, and acrB resistance determinants in E. coli and K. pneumoniae is a great concern. Therefore, infection control and prevention of spread of drug-resistant bacteria need careful management of medication and identification of resistant isolates.

Use of the Escherichia coli Identification Microarray for Characterizing the Health Risks of Shiga Toxin-Producing Escherichia coli Isolated from Foods.

PubMed

Lacher, David W; Gangiredla, Jayanthi; Patel, Isha; Elkins, Christopher A; Feng, Peter C H

2016-10-01

More than 470 serotypes of Shiga toxin-producing Escherichia coli (STEC) have been identified, but not all cause severe illness in humans. Most STEC that cause severe diseases can adhere to epithelial cells, produce specific stx subtypes, and belong to certain serotypes; therefore, these traits appear to be critical STEC risk factors. However, testing for these traits is labor intensive, and serotyping is inadequate because of extensive variations among E. coli O and H antigen types. In the present study, the E. coli identification microarray, which tests for over 40,000 E. coli gene targets, was examined for its potential to quickly characterize STEC strains. Analysis of 47 E. coli isolates, including 31 STEC isolates, recovered from 39 foods revealed that the microarray effectively determined the presence or absence of adherence genes and identified the specific eae allele in 3 isolates. The array identified most of the stx subtypes carried by all the isolates but had some difficulties in discerning between stx 2a , stx 2c , and stx 2d because of the genetic similarities of these subtypes. The array determined the O and H types of 68 and 96% of the isolates, respectively, and although most serotypes were unremarkable, a few known pathogenic serotypes were also found. These selected STEC traits provided a scientific basis for assessing the potential health risks of STEC strains and also showed the importance of H typing in determining health risks. However, the diversity of the STEC group, the complexity of virulence mechanisms, and the variation in pathotypes among strains continue to pose challenges to assessing the potential of STEC strains to cause severe illness.

Escherichia coli isolates from inflammatory bowel diseases patients survive in macrophages and activate NLRP3 inflammasome.

PubMed

De la Fuente, Marjorie; Franchi, Luigi; Araya, Daniela; Díaz-Jiménez, David; Olivares, Mauricio; Álvarez-Lobos, Manuel; Golenbock, Douglas; González, María-Julieta; López-Kostner, Francisco; Quera, Rodrigo; Núñez, Gabriel; Vidal, Roberto; Hermoso, Marcela A

2014-05-01

Crohn's disease (CD) is a multifactorial pathology associated with the presence of adherent-invasive Escherichia coli (AIEC) and NLRP3 polymorphic variants. The presence of intracellular E. coli in other intestinal pathologies (OIP) and the role of NLRP3-inflammasome in the immune response activated by these bacteria have not been investigated. In this study, we sought to characterize intracellular strains isolated from patients with CD, ulcerative colitis (UC) and OIP, and analyze NLRP3-inflammasome role in the immune response and bactericidal activity induced in macrophages exposed to invasive bacteria. For this, intracellular E. coli isolation from ileal biopsies, using gentamicin-protection assay, revealed a prevalence and CFU/biopsy of E. coli higher in biopsies from CD, UC and OIP patients than in controls. To characterize bacterial isolates, pulsed-field gel electrophoresis (PFGE) patterns, virulence genes, serogroup and phylogenetic group were analyzed. We found out that bacteria isolated from a given patient were closely related and shared virulence factors; however, strains from different patients were genetically heterogeneous. AIEC characteristics in isolated strains, such as invasive and replicative properties, were assessed in epithelial cells and macrophages, respectively. Some strains from CD and UC demonstrated AIEC properties, but not strains from OIP. Furthermore, the role of NLRP3 in pro-inflammatory cytokines production and bacterial elimination was determined in macrophages. E. coli strains induced IL-1β through NLRP3-dependent mechanism; however, their elimination by macrophages was independent of NLRP3. Invasiveness of intracellular E. coli strains into the intestinal mucosa and IL-1β production may contribute to CD and UC pathogenesis. Copyright © 2014 Elsevier GmbH. All rights reserved.

Prevalence of adhesin and toxin genes in E. coli strains isolated from diarrheic and non-diarrheic pigs from smallholder herds in northern and eastern Uganda.

PubMed

Ikwap, Kokas; Larsson, Jenny; Jacobson, Magdalena; Owiny, David Okello; Nasinyama, George William; Nabukenya, Immaculate; Mattsson, Sigbrit; Aspan, Anna; Erume, Joseph

2016-08-05

Enterotoxigenic E. coli (ETEC) significantly contribute to diarrhea in piglets and weaners. The smallholder pig producers in Uganda identified diarrhea as one of the major problems especially in piglets. The aim of this study was to; i) characterize the virulence factors of E. coli strains isolated from diarrheic and non-diarrheic suckling piglets and weaners from smallholder herds in northern and eastern Uganda and ii) identify and describe the post-mortem picture of ETEC infection in severely diarrheic piglets. Rectal swab samples were collected from 83 piglets and weaners in 20 herds and isolated E. coli were characterized by PCR, serotyping and hemolysis. The E. coli strains carried genes for the heat stable toxins STa, STb and EAST1 and adhesins F4 and AIDA-I. The genes for the heat labile toxin LT and adhesins F5, F6, F18 and F41 were not detected in any of the E. coli isolates. Where the serogroup could be identified, E. coli isolates from the same diarrheic pig belonged to the same serogroup. The prevalence of EAST1, STb, Stx2e, STa, AIDA-I, and F4 in the E. coli isolates from suckling piglets and weaners (diarrheic and non-diarrheic combined) was 29, 26.5, 2.4, 1.2, 16, and 8.4 %, respectively. However the prevalence of F4 and AIDA-I in E. coli from diarrheic suckling piglets alone was 22.2 and 20 %, respectively. There was no significant difference in the prevalence of the individual virulence factors in E. coli from the diarrheic and non-diarrheic pigs (p > 0.05). The main ETEC strains isolated from diarrheic and non-diarrheic pigs included F4/STb/EAST1 (7.2 %), F4/STb (1.2 %), AIDA/STb/EAST1 (8 %) and AIDA/STb (8 %). At post-mortem, two diarrheic suckling piglets carrying ETEC showed intact intestinal villi, enterocytes and brush border but with a layer of cells attached to the brush border, suggestive of ETEC infections. This study has shown that the F4 fimbriae is the most predominant in E. coli from diarrheic piglets in the study area and therefore an F4-based vaccine should be considered one of the preventive measures for controlling ETEC infections in the piglets in northern and eastern Uganda.

Aerobic bacteria from mucous membranes, ear canals, and skin wounds of feral cats in Grenada, and the antimicrobial drug susceptibility of major isolates.

PubMed

Hariharan, Harry; Matthew, Vanessa; Fountain, Jacqueline; Snell, Alicia; Doherty, Devin; King, Brittany; Shemer, Eran; Oliveira, Simone; Sharma, Ravindra N

2011-03-01

In a 2-year period 54 feral cats were captured in Grenada, West Indies, and a total of 383 samples consisting of swabs from rectum, vagina, ears, eyes, mouth, nose and wounds/abscesses, were cultured for aerobic bacteria and campylobacters. A total of 251 bacterial isolates were obtained, of which 205 were identified to species level and 46 to genus level. A commercial bacterial identification system (API/Biomerieux), was used for this purpose. The most common species was Escherichia coli (N=60), followed by Staphylococcus felis/simulans (40), S. hominis (16), S. haemolyticus (12), Streptococcus canis (9), Proteus mirabilis (8), Pasteurella multocida (7), Streptococcus mitis (7), Staphylococcus xylosus (7), S. capitis (6), S. chromogenes (4), S. sciuri (3), S. auricularis (2), S. lentus (2), S. hyicus (2), Streptococcus suis (2) and Pseudomonas argentinensis (2). Sixteen other isolates were identified to species level. A molecular method using 16S rRNA sequencing was used to confirm/identify 22 isolates. Salmonella or campylobacters were not isolated from rectal swabs. E. coli and S. felis/simulans together constituted 50% of isolates from vagina. S. felis/simulans was the most common species from culture positive ear and eye samples. P. multocida was isolated from 15% of mouth samples. Coagulase-negative staphylococci were the most common isolates from nose and wound swabs. Staphylococcus aureus, or S. intemedius/S. pseudintermedius were not isolated from any sample. Antimicrobial drug resistance was minimal, most isolates being susceptible to all drugs tested against, including tetracycline. Copyright © 2010 Elsevier Ltd. All rights reserved.

Genetic diversity of thermotolerant Campylobacter spp. isolates from different stages of the poultry meat supply chain in Argentina.

PubMed

Zbrun, María V; Romero-Scharpen, Analía; Olivero, Carolina; Zimmermann, Jorge A; Rossler, Eugenia; Soto, Lorena P; Astesana, Diego M; Blajman, Jesica E; Berisvil, Ayelén; Frizzo, Laureano S; Signorini, Marcelo L

The objective of this study was to investigate a clonal relationship among thermotolerant Campylobacter spp. isolates from different stages of the poultry meat supply chain in Argentina. A total of 128 thermotolerant Campylobacter spp. (89 C. jejuni and 39 C. coli) isolates from six poultry meat chains were examined. These isolates were from: a) hens from breeder flocks, b) chickens on the farm (at ages 1 wk and 5 wk), c) chicken carcasses in the slaughterhouse, and d) chicken carcasses in the retail market. Chickens sampled along each food chain were from the same batch. Campylobacter spp. isolates were analyzed using pulsed-field gel electrophoresis to compare different profiles according to the source. Clustering of C. jejuni isolates resulted in 17 profiles, with four predominant genotypes and many small profiles with just a few isolates or unique patterns, showing a very high degree of heterogeneity among the C. jejuni isolates. Some clusters included isolates from different stages within the same chain, which would indicate a spread of strains along the same poultry meat chain. Moreover, twenty-two strains of C. coli clustered in seven groups and the remaining 17 isolates exhibited unique profiles. Evidence for transmission of thermotolerant Campylobacter spp. through the food chain and cross contamination in the slaughterhouses were obtained. This collective evidence should be considered as the scientific basis to implement risk management measures to protect the public health. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Complete sequence of a colistin resistance gene (mcr-1) bearing isolate of Escherichia coli from the United States

USDA-ARS?s Scientific Manuscript database

Transmissible colistin resistance conferred by mcr-1 gene bearing IncI2 plasmid has been recently reported in Esherichia coli in the US. We report the completed genome sequence of a second E. coli isolated from swine in the US that carried the mcr-1 gene on an IncI2 type plasmid....

Seagulls of the Berlengas natural reserve of Portugal as carriers of fecal Escherichia coli harboring CTX-M and TEM extended-spectrum beta-lactamases.

PubMed

Poeta, Patricia; Radhouani, Hajer; Igrejas, Gilberto; Gonçalves, Alexandre; Carvalho, Carlos; Rodrigues, Jorge; Vinué, Laura; Somalo, Sergio; Torres, Carmen

2008-12-01

Escherichia coli isolates containing the following extended-spectrum beta-lactamases have been detected in 11 of 57 fecal samples (19.3%) in Berlengas Island seagulls: TEM-52 (eight isolates), CTX-M-1 (one isolate), CTX-M-14a (one isolate), and CTX-M-32 (one isolate). Most of the extended-spectrum beta-lactamase-positive isolates harbored class 1 or class 2 integrons, which included different antibiotic resistance gene cassettes.

Seagulls of the Berlengas Natural Reserve of Portugal as Carriers of Fecal Escherichia coli Harboring CTX-M and TEM Extended-Spectrum Beta-Lactamases▿

PubMed Central

Poeta, Patricia; Radhouani, Hajer; Igrejas, Gilberto; Gonçalves, Alexandre; Carvalho, Carlos; Rodrigues, Jorge; Vinué, Laura; Somalo, Sergio; Torres, Carmen

2008-01-01

Escherichia coli isolates containing the following extended-spectrum beta-lactamases have been detected in 11 of 57 fecal samples (19.3%) in Berlengas Island seagulls: TEM-52 (eight isolates), CTX-M-1 (one isolate), CTX-M-14a (one isolate), and CTX-M-32 (one isolate). Most of the extended-spectrum beta-lactamase-positive isolates harbored class 1 or class 2 integrons, which included different antibiotic resistance gene cassettes. PMID:18835997

Evaluation of adherence, hemagglutination, and presence of genes codifying for virulence factors of Acinetobacter baumannii causing urinary tract infection.

PubMed

Braun, Graziela; Vidotto, Marilda Carlos

2004-12-01

Acinetobacter baumannii is a strictly aerobic bacterium which causes severe infections, however its pathogenic characteristics are not well defined. Thirteen A. baumannii strains isolated from urine of hospitalized and nonhospitalized patients with different ages were investigated for the presence of virulence factors. The isolates belonged to biotypes 2, 6, and 9 and were sensitive to imipenem. The majority of them showed resistance to amikacin, ceftazidime, ceftriaxone, ciprofloxacin, gentamicin, norfloxacin, and trimethoprim-sulfamethoxazole. None of A. baumannii strains presented genes codifying for 17 different virulence factors previously described in uropathogenic Escherichia coli, when tested by polymerase chain reaction (PCR). Nine isolates agglutinated human group AB erythrocytes, in presence of mannose, but none of them agglutinated group O erythrocytes. Adherence to polystyrene was observed in 7 isolates, and this result did not correlate with that obtained in hemagglutination assay. All the isolates were able to grow in iron-limiting conditions, showing that A. baumannii produces some type of siderophore. However, the genes iutA and fyuA, from iron uptake system of E. coli and Yersinia sp., respectively, were not present in the isolates, suggesting the presence of a different type of siderophore. The fimbriae of A. baumannii strains that mediates the adherence are possibly mannose-resistant, even though the mechanism of adherence to human epithelial cells still remains to be elucidated.

Characteristics of Transmissible CTX-M- and CMY-Type β-Lactamase-Producing Escherichia coli Isolates Collected from Pig and Chicken Farms in South Korea.

PubMed

Shin, Seung Won; Jung, Myunghwan; Won, Ho Geun; Belaynehe, Kuastros Mekonnen; Yoon, In Joong; Yoo, Han Sang

2017-09-28

The rapid dissemination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli has significantly contributed to public health hazard globally. A total of 281 E. coli strains recovered from pigs and chickens between 2009 and 2015 in South Korea were analyzed for ESBL production. ESBL phenotypes were recognized in 14 E. coli isolates; ten and three ESBLproducing isolates carried only bla CTX-M and bla CMY genes, respectively, and one isolate harbored both genes. The predominant CTX-M and CMY types were CTX-M-15 (n = 8) and CMY-2 (n = 3). We also detected ESBL-producing isolates harboring bla CTX-M-65 , bla CTX-M-14 , bla CMY-6 , bla DHA-1 , and bla TEM-1 genes. All ESBL-producing isolates showed resistance to the extent of the fourth generation cephalosporins, along with multidrug resistance. CTX-M-15- producing isolates showed higher MIC values than CTX-M-14- and CTX-M-65-producing isolates. The bla CTX-M and bla CMY genes have the potential to be transferable. The spreading of bla CMY and bla CTX-M genes was arbitrated mainly v ia F rep a nd I ncI1 plasmids. Our i solates showed clonal diversity in PFGE analysis. This is the first report of E. coli isolates carrying bla CMY-6 in chicken from South Korea. The emergence of CMY-6 ESBLs in a population of poultry suggests that extensive screening with long-term surveillance is necessary to prevent the dissemination of ESBL from chicken to human.

Role of Poultry Meat in Sporadic Campylobacter Infections in Bosnia and Herzegovina: Laboratory-based Study

PubMed Central

Uzunović-Kamberović, Selma; Zorman, Tina; Heyndrickx, Marc; Smole Možina, Sonja

2007-01-01

Aim To investigate genetic diversity and specificity of Campylobacter jejuni and Campylobacter coli strains isolated from humans, retail poultry meat, and live farm chickens in Zenica-Doboj Canton, Bosnia and Herzegovina, and identify the role of poultry meat in sporadic Campylobacter infections. Methods We determined the type of Campylobacter species using standard microbiological methods and multiplex polymerase chain reaction (PCR), and performed pulsed field gel-electrophoresis (PFGE) and restriction fragment length polymorphism (RFLP) typing of the flaA gene to investigate genetic diversity among the isolates. Results We isolated C jejuni and C coli from 75 (5.2%) of 1453 samples of consecutive outpatients with sporadic diarrhea; from 51 (34.7%) of 147 samples of poultry meat; and from 15 out of 23 farm chicken samples. The proportion of C coli found among human (30.1%), poultry meat (56.9%), and farm chicken isolates (53.3%), was greater than the proportion of C jejuni. Fourteen and 24 PFGE genotypes were identified among 20 C coli and 37 C jejuni isolates, respectively. Identical PFGE genotypes were found in two cases of human and poultry meat isolates and two cases of poultry meat and farm chicken isolates. Conclusion Only a minority of human Campylobacter isolates shared identical PFGE type with poultry meat isolates. Although poultry is the source of a certain number of human infections, there may be other more important sources. Further research is required to identify the environmental reservoir of Campylobacter spp responsible for causing human disease and the reason for the high prevalence of C coli human infections in this region. PMID:18074419

Intergenic Sequence Comparison of Escherichia coli Isolates Reveals Lifestyle Adaptations but Not Host Specificity▿

PubMed Central

White, A. P.; Sibley, K. A.; Sibley, C. D.; Wasmuth, J. D.; Schaefer, R.; Surette, M. G.; Edge, T. A.; Neumann, N. F.

2011-01-01

Establishing the risk of human infection is one of the goals of public health. For bacterial pathogens, the virulence and zoonotic potential can often be related to their host source. Escherichia coli bacteria are common contaminants of water associated with human recreation and consumption, and many strains are pathogenic. In this study, we analyzed three promoter-containing intergenic regions from 284 diverse E. coli isolates in an attempt to identify molecular signatures associated with specific host types. Promoter sequences controlling production of curli fimbriae, flagella, and nutrient import yielded a phylogenetic tree with isolates clustered by established phylogenetic grouping (A, B1, B2, and D) but not by host source. Virulence genes were more prevalent in groups B2 and D isolates and in human isolates. Group B1 isolates, primarily from nonhuman sources, were the most genetically similar, indicating that they lacked molecular adaptations to specific host environments and were likely host generalists. Conversely, B2 isolates, primarily from human sources, displayed greater genetic distances and were more likely to be host adapted. In agreement with these hypotheses, prevalence of σS activity and the rdar morphotype, phenotypes associated with environmental survival, were significantly higher in B1 isolates than in B2 isolates. Based on our findings, we speculate that E. coli host specificity is not defined by genome-wide sequence changes but, rather, by the presence or absence of specific genes and associated promoter elements. Furthermore, the requirements for colonization of the human gastrointestinal tract may lead to E. coli lifestyle changes along with selection for increased virulence. PMID:21908635

Characterization of antimicrobial resistance of Escherichia coli recovered from foods of animal and fish origin in Korea.

PubMed

Koo, Hyon-Ji; Woo, Gun-Jo

2012-05-01

Antimicrobial-resistant Escherichia coli is transferred from food-producing animals to humans through the food chain. We investigated the prevalence of antimicrobial resistance and resistance determinants and characterized the integrons of foodborne E. coli in Korea. In total, 162 E. coli isolates from commercial foods (raw meat, fish, and processed foods) were collected by the National Antimicrobial Resistance Management Program from 2004 to 2006. Susceptibility to 20 antibiotics was tested by disk diffusion, and resistance determinants were detected using PCR and genomic sequence analysis. The isolates were highly resistant to antibiotics commonly used in livestock farming. Resistance to tetracycline (74.7%) was the most frequently observed, followed by streptomycin (71%) and ampicillin (51.2%). Class 1 integrons were detected in 13 isolates (8%), and nine of these integrons were located on conjugative plasmids. None of the isolates produced extended-spectrum β -lactamase. One isolate (0.6%) harbored bla(CMY-2), which was located on a conjugative plasmid. Although the qnr gene was not detected, aac(6'9)-Ib-cr was present in two isolates (1.2%). This is the first report of aac(6'9)-Ib-cr in food isolates. Three or four amino acid substitutions at positions 83 and 87 in gyrA and at positions 80 and/or 84 in parC were found in six isolates, representing high resistance to ciprofloxacin (MIC ≥ 16 mg/liter). These results suggest that E. coli isolates carrying resistance genes and integrons are present in the Korean food chain.

Recent emergence of clonal group O25b:K1:H4-B2-ST131 ibeA strains among Escherichia coli poultry isolates, including CTX-M-9-producing strains, and comparison with clinical human isolates.

PubMed

Mora, Azucena; Herrera, Alexandra; Mamani, Rosalia; López, Cecilia; Alonso, María Pilar; Blanco, Jesús E; Blanco, Miguel; Dahbi, Ghizlane; García-Garrote, Fernando; Pita, Julia María; Coira, Amparo; Bernárdez, María Isabel; Blanco, Jorge

2010-11-01

To discern the possible spread of the Escherichia coli O25b:H4-ST131 clonal group in poultry and the zoonotic potential of avian strains, we made a retrospective search of our strain collection and compared the findings for those strains with the findings for current strains. Thus, we have characterized a collection of 19 avian O25b:H4-ST131 E. coli strains isolated from 1995 to 2010 which, interestingly, harbored the ibeA gene. Using this virulence gene as a criterion for selection, we compared those 19 avian strains with 33 human O25b:H4-ST131 ibeA-positive E. coli strains obtained from patients with extraintestinal infections (1993 to 2009). All 52 O25b:H4-ST131 ibeA-positive E. coli strains shared the fimH, kpsMII, malX, and usp genes but showed statistically significant differences in nine virulence factors, namely, papGIII, cdtB, sat, and kpsMII K5, which were associated with human strains, and iroN, kpsMII K1, cvaC, iss, and tsh, which were associated with strains of avian origin. The XbaI macrorestriction profiles of the 52 E. coli O25b:H4-ST131 ibeA-positive strains revealed 11 clusters (clusters I to XI) of >85% similarity, with four clusters including strains of human and avian origin. Cluster VII (90.9% similarity) grouped 10 strains (7 avian and 3 human strains) that mostly produced CTX-M-9 and that also shared the same virulence profile. Finally, we compared the macrorestriction profiles of the 12 CTX-M-9-producing O25b:H4-ST131 ibeA strains (7 avian and 5 human strains) identified among the 52 strains with those of 15 human O25b:H4-ST131 CTX-M-14-, CTX-M-15-, and CTX-M-32-producing strains that proved to be negative for ibeA and showed that they clearly differed in the level of similarity from the CTX-M-9-producing strains. In conclusion, E. coli clonal group O25b:H4-ST131 ibeA has recently emerged among avian isolates with the new acquisition of the K1 capsule antigen and includes CTX-M-9-producing strains. This clonal group represents a real zoonotic risk that has crossed the barrier between human and avian hosts.

Limazepines A-F, pyrrolo[1,4]benzodiazepine Antibiotics from an Indonesian Micrococcus sp.

PubMed

Fotso, Serge; Zabriskie, T Mark; Proteau, Philip J; Flatt, Patricia M; Santosa, Dwi Andreas; Mahmud, Taifo

2009-04-01

In our screening of Indonesian microorganisms for novel bioactive natural products we have isolated seven new compounds, designated as limazepines A, B1 and B2 (isolated as an isomeric mixture), C, D, E, and F, from the culture broth of Micrococcus sp. strain ICBB 8177. In addition, the known natural products prothracarcin and 7-O-succinylmacrolactin A, as well as two previously reported synthetic compounds, 2-amino-3-hydroxy-4-methoxybenzoic acid methyl ester and 4-ethylpyrrole-2-carboxaldehyde, were obtained from the extract. Chemical structures were determined by spectroscopic methods and by comparison with the NMR data of structurally related compounds. The limazepines belong to the growing group of the pyrrolo[1,4]benzodiazepine antitumor antibiotics isolated from various soil bacteria. Limazepines B1/B2 mixture, C, and E were active against the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Escherichia coli. Limazepine D was also active against S. aureus, but was not active against E. coli. Interestingly, only the limazepines B1/B2 mixture and D were active against Pseudomonas aeruginosa.

Molecular and clinical characterization of plasmid-mediated AmpC β-lactamase-producing Escherichia coli bacteraemia: a comparison with extended-spectrum β-lactamase-producing and non-resistant E. coli bacteraemia.

PubMed

Matsumura, Y; Nagao, M; Iguchi, M; Yagi, T; Komori, T; Fujita, N; Yamamoto, M; Matsushima, A; Takakura, S; Ichiyama, S

2013-02-01

Plasmid-mediated AmpC β-lactamase-producing Escherichia coli (AmpC-E) bacteraemia was characterized by comparison with bacteraemia caused by extended-spectrum β-lactamase (ESBL)-producing E. coli (ESBL-E) and non-resistant E. coli (NR-E) in the era of the worldwide spread of the CTX-M-15-producing O25b-ST131-B2 clone. Of 706 bloodstream E. coli isolates collected between 2005 and 2010 in three Japanese university hospitals, 111 ESBL screening-positive isolates were analysed for AmpC and ESBL genes by PCR. A case-control study was performed in which the cases consisted of all of the patients with AmpC-E bacteraemia. Phylogenetic groups, sequence types and O25b serotype were determined. Twenty-seven AmpC-E isolates (26 of which were of the CMY-2 type) were identified, and 54 ESBL-E and 54 NR-E isolates were selected for the controls. Nineteen AmpC-E isolates were also positive for ESBL. CTX-M-14 was the most prevalent ESBL type among both the AmpC-E and ESBL-E isolates. The O25b-ST131-B2 clone was the most prevalent among the ESBL-E isolates (26%) and the second most prevalent among the NR-E isolates (13%), but only one O25b-ST131-B2 clone was found among the AmpC-E isolates. Twenty-three different sequence types were identified among the AmpC-E isolates. When compared with bacteraemia with ESBL-E, previous isolation of multidrug-resistant bacteria and intravascular catheterization were independently associated with a lower risk for AmpC-E. When compared with NR-E bacteraemia, prior use of antibiotics was the only significant risk factor for AmpC-E. Unlike the spread of the O25b-ST131-B2 clone between ESBL-E and NR-E, the AmpC-E isolates were not dominated by any specific clone. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.

Prevalence of ESBLs and PMQR genes in fecal Escherichia coli isolated from the non-human primates in six zoos in China.

PubMed

Wang, Yang; He, Tao; Han, Jing; Wang, Juan; Foley, Steven L; Yang, Guangyou; Wan, Shuangxiu; Shen, Jianzhong; Wu, Congming

2012-09-14

The aim of this study is to characterize the prevalence of extended-spectrum β-lactamases (ESBLs) and plasmid-mediated quinolone resistance (PMQR) genes in Escherichia coli from captive non-human primates. A total of 206 E. coli isolates were collected from primates in six zoos in China in 2009 and their susceptibility to 10 antimicrobials were tested by broth microdilution. The susceptibility patterns of E. coli strains varied greatly among different zoos reflecting different backgrounds of antimicrobial usage. Both the ESBL-encoding genes and the PMQR genes were detected by PCR. Of the 206 strains, 65 (32%) were confirmed as phenotypic ESBL producers with bla(CTX-M) (27%, bla(CTX-M-15), n=31, bla(CTX-M-3), n=23 and bla(CTX-M-14), n=2) mainly mediating the ESBL phenotype. qnrS1 (18%, n=36) and oqxAB (15%, n=31) were the predominant PMQR genes and the prevalence of PMQR genes was much higher among phenotypic ESBL producers than that among phenotypic non-ESBL producers from any zoo. Notably, the PMQR genes qnrS1 and oqxAB and β-lactamase genes bla(TEM-1) and bla(CTX-M-3) were found together in 23 E. coli isolates in two zoos in Shanghai. PFGE analysis of these 23 isolates demonstrated nearly identical PFGE profiles (similarity matrix >97%) indicating this specific E. coli genotype was prevalent in these two zoos. To the best of our knowledge, this is the first report of these four genes coexisting in an E. coli genotype and the first report of antimicrobial resistance profiles in E. coli isolated from primates in China. Copyright © 2012 Elsevier B.V. All rights reserved.

Genetic & virulence profiling of ESBL-positive E. coli from nosocomial & veterinary sources.

PubMed

Tyrrell, J M; Wootton, M; Toleman, M A; Howe, R A; Woodward, M; Walsh, T R

2016-04-15

CTX-M genes are the most prevalent ESBL globally, infiltrating nosocomial, community and environmental settings. Wild and domesticated animals may act as effective vectors for the dissemination of CTX-producing Enterobacteriaceae. This study aimed to contextualise blaCTX-M-14-positive, cephalosporin-resistant Enterobacteriaceae human infections and compared resistance and pathogenicity markers with veterinary isolates. Epidemiologically related human (n=18) and veterinary (n=4) blaCTX-M-14-positive E. coli were fully characterised. All were typed by XbaI pulsed field gel electrophoresis and ST. Chromosomal/plasmidic locations of blaCTX-M-14 were deduced by S1-nuclease digestion, and association with ISEcp1 was investigated by sequencing. Conjugation experiments assessed transmissibility of plasmids carrying blaCTX-M-14. Presence of virulence determinants was screened by PCR assay and pathogenicity potential was determined by in vitro Galleria mellonella infection models. 84% of clinical E. coli originated from community patients. blaCTX-M-14 was found ubiquitously downstream of ISEcp1 upon conjugative plasmids (25-150 kb). blaCTX-M-14 was also found upon the chromosome of eight E. coli isolates. CTX-M-14-producing E. coli were found at multiple hospital sites. Clonal commonality between patient, hospitals and livestock microbial populations was found. In vivo model survival rates from clinical isolates (30%) and veterinary isolates (0%) were significantly different (p<0.05). Co-transfer of blaCTX-M-14 and virulence determinants was demonstrated. There is evidence of clonal spread of blaCTX-M-14-positive E. coli involving community patients and farm livestock. blaCTX-M-14 positive human clinical isolates carry a lower intrinsic pathogenic potential than veterinary E. coli highlighting the need for greater veterinary practices in preventing dissemination of MDR E. coli among livestock. Copyright © 2016. Published by Elsevier B.V.

Pilot Study of Antimicrobial Resistance in Northern Bobwhites (Colinus virginianus).

PubMed

Zhang, Michael; Shen, Zhenyu; Rollins, Dale; Fales, William; Zhang, Shuping

2017-09-01

Antimicrobial resistance (AMR) is an important issue for both wildlife conservation and public health. The purpose of this study was to screen for AMR in fecal bacteria isolated from northern bobwhite (Colinus virginianus), a species that is an ecologically and economically important natural resource in the southern United States. The antimicrobial susceptibility profiles of 45 Escherichia coli isolates, 20 Enterococcus faecalis isolates, and 10 Enterococcus faecium isolates were determined using the Sensititer TM microbroth dilution minimum inhibitory concentration (MIC) plate, AVIAN1F. Overall, E. coli isolates had high MIC values for the following classes of antimicrobials: aminocoumarins, beta-lactams, lincosamides, macrolides, florfenicol, and sulfonamides. Enterococcus faecalis and E. faecium isolates had high MICs for aminocyclitols, aminoglycosides, beta-lactams, lincosamides, and sulfonamides. Enterococcus faecalis isolates also showed high MICs for aminocoumarins, while E. faecium isolates had high MICs for trimethoprim/sulfamethoxazole and tetracycline. Based on available veterinary interpretive criteria, 15% and 33% of E. coli isolates were resistant to sulphathiazole and sulphadimethoxine, respectively. Intermediate susceptibility to florfenicol was seen with 17.8% of E. coli isolates. Twenty percent of E. faecalis and 80% of E. faecium isolates were resistant to high-concentration streptomycin. One third of E. faecalis and 70% of E. faecium isolates were intermediately susceptible to erythromycin. Ten percent of E. faecium isolates were resistant to tetracycline and oxytetracycline. A comparison of available MIC suggests that AMR in wild bobwhite is less severe than in domestic poultry. Further investigation is needed to determine the source of AMR in wild bobwhite.

Complete genome sequence of the clinical Campylobacter coli isolate 15-537360

USDA-ARS?s Scientific Manuscript database

Campylobacter coli strain 15-537360 was originally isolated from a 42 year-old patient with gastroenteritis. Here we report its complete genome sequence, which comprises a 1.7 Mbp chromosome and a 29 kbp conjugative cryptic plasmid. This is the first complete genome sequence of a clinical isolate of...

Preponderance of toxigenic Escherichia coli in stool pathogens correlates with toxin detection in accessible drinking-water sources.

PubMed

Igbokwe, H; Bhattacharyya, S; Gradus, S; Khubbar, M; Griswold, D; Navidad, J; Igwilo, C; Masson-Meyers, D; Azenabor, A A

2015-02-01

Since early detection of pathogens and their virulence factors contribute to intervention and control strategies, we assessed the enteropathogens in diarrhoea disease and investigated the link between toxigenic strains of Escherichia coli from stool and drinking-water sources; and determined the expression of toxin genes by antibiotic-resistant E. coli in Lagos, Nigeria. This was compared with isolates from diarrhoeal stool and water from Wisconsin, USA. The new Luminex xTAG GPP (Gastroplex) technique and conventional real-time PCR were used to profile enteric pathogens and E. coli toxin gene isolates, respectively. Results showed the pathogen profile of stool and indicated a relationship between E. coli toxin genes in water and stool from Lagos which was absent in Wisconsin isolates. The Gastroplex technique was efficient for multiple enteric pathogens and toxin gene detection. The co-existence of antibiotic resistance with enteroinvasive E. coli toxin genes suggests an additional prognostic burden on patients.

[E. coli: resistance to quinolones and beta-lactams of clinical strains isolated in the Franche-Comté region of France].

PubMed

Talon, D; Lallemand-De-Conto, S; Thouverez, M; Bertrand, X

2004-03-01

Numerous European studies have reported an increase of resistance to quinolones among E. coli. We conducted a regional study to update our knowledge on this evolution. We evaluated the resistance phenotype and genotype of 115 clinical strains of E. coli. We collected data on individual treatment with fluoroquinolones, and the evolution of the use of these antimicrobial agents. Resistance to nalidixic acid and ciprofloxacin was 13.0 and 6.9, respectively. The frequency of resistance increased from 1999 to 2001, from 7.5% to 13.0% for nalidixic acid and from 5.4% to 6.9% for fluoroquinolones. Resistance to quinolones was significantly associated to beta-lactams resistance and was slightly higher for nosocomial isolates compared to community-acquired isolates. Previous treatment with fluoroquinolones was the major risk factor associated to E. coli resistance. From 1997 to 2001, fluoroquinolones use has increased in our hospital and particularly in the community. Analysis of molecular epidemiology shows a large clonal diversity among E. coli isolates. This study confirms the evolution through resistance to quinolones of E. coli isolates. This observation is not due to dissemination of resistant clonal strains and the selective pressure exerted by fluoroquinolones influences this evolution. Therapeutic alternatives, surveillance, and restriction of fluoroquinolones use are needed to control this spread of resistance.

Using the agricultural environment to select better surrogates for foodborne pathogens associated with fresh produce.

PubMed

Cook, Kimberly L; Givan, Ethan C; Mayton, Holly M; Parekh, Rohan R; Taylor, Ritchie; Walker, Sharon L

2017-12-04

Despite continuing efforts to reduce foodborne pathogen contamination of fresh produce, significant outbreaks continue to occur. Identification of appropriate surrogates for foodborne pathogens facilitates relevant research to identify reservoirs and amplifiers of these contaminants in production and processing environments. Therefore, the objective of this study was to identify environmental Escherichia coli isolates from manures (poultry, swine and dairy) and surface water sources with properties similar to those of the produce associated foodborne pathogens E. coli O157:H7 and Salmonella enterica serotype Typhimurium. The most similar environmental E. coli isolates were from poultry (n=3) and surface water (n=1) sources. The best environmental E. coli surrogates had cell surface characteristics (zeta potential, hydrophobicity and exopolysaccharide composition) that were similar (i.e., within 15%) to those of S. Typhimurium and/or formed biofilms more often when grown in low nutrient media prepared from lettuce lysates (24%) than when grown on high nutrient broth (7%). The rate of attachment of environmental isolates to lettuce leaves was also similar to that of S. Typhimurium. In contrast, E. coli O157:H7, a commonly used E. coli quality control strain and swine isolates behaved similarly; all were in the lowest 10% of isolates for biofilm formation and leaf attachment. These data suggest that the environment may provide a valuable resource for selection of surrogates for foodborne pathogens. Published by Elsevier B.V.

Route of infection alters virulence of neonatal septicemia Escherichia coli clinical isolates

PubMed Central

Cole, Bryan K.; Scott, Edgar; Ilikj, Marko; Bard, David; Akins, Darrin R.; Dyer, David W.

2017-01-01

Escherichia coli is the leading cause of Gram-negative neonatal septicemia in the United States. Invasion and passage across the neonatal gut after ingestion of maternal E. coli strains produce bacteremia. In this study, we compared the virulence properties of the neonatal E. coli bacteremia clinical isolate SCB34 with the archetypal neonatal E. coli meningitis strain RS218. Whole-genome sequencing data was used to compare the protein coding sequences among these clinical isolates and 33 other representative E. coli strains. Oral inoculation of newborn animals with either strain produced septicemia, whereas intraperitoneal injection caused septicemia only in pups infected with RS218 but not in those injected with SCB34. In addition to being virulent only through the oral route, SCB34 demonstrated significantly greater invasion and transcytosis of polarized intestinal epithelial cells in vitro as compared to RS218. Protein coding sequences comparisons highlighted the presence of known virulence factors that are shared among several of these isolates, and revealed the existence of proteins exclusively encoded in SCB34, many of which remain uncharacterized. Our study demonstrates that oral acquisition is crucial for the virulence properties of the neonatal bacteremia clinical isolate SCB34. This characteristic, along with its enhanced ability to invade and transcytose intestinal epithelium are likely determined by the specific virulence factors that predominate in this strain. PMID:29236742

Some virulence characteristics of uropathogenic Escherichia coli in different patient groups.

PubMed

Naveen, Rebecca; Mathai, Elizabeth

2005-08-01

Uropathogenic Escherichia coli have virulence properties, that are absent in non pathogenic E. coli. The distribution of these markers can vary according to patient populations. Hence, a study was undertaken to describe the presence of virulence factors like Pfimbriae, type 1 fimbriae and haemolysin in E.coli causing urinary infections in three groups of patients. Antibiogram was also recorded to determine differences, if any, between the groups. E. coli isolated from three groups of subjects, in counts of >10(5) CFU/ml and in pure growth were tested for mannose resistant haemagglutination (MRHA) to indicate P fimbriae and mannose sensitive haemagglutination (MSHA) to indicate type 1 fimbriae. Haemolysin production and antimicrobial susceptibility patterns were also recorded. Significantly more isolates from antenatal and postnatal women possessed P fimbriae compared to groups with urologic abnormalities (P=0.05). Haemolysin production was also significantly higher (P<0.001) in this group. Greater proportions of isolates from pregnant women were susceptible to commonly used antimicrobials. However, resistance to third generation cephalosporins was present even in these isolates from community infections. In patients with urological abnormality, E. coli with lower virulence can cause infections. Isolates from these patients exhibited greater drug resistance. In pregnant women and in community acquired infections, simple antimicrobial drugs like nitrofurantoin might still be useful. However, urgent and stringent policies for antimicrobial use and infection control in hospitals are required in India.

Prevalence of Avian-Pathogenic Escherichia coli Strain O1 Genomic Islands among Extraintestinal and Commensal E. coli Isolates

PubMed Central

Johnson, Timothy J.; Wannemuehler, Yvonne; Kariyawasam, Subhashinie; Johnson, James R.; Logue, Catherine M.

2012-01-01

Escherichia coli strains that cause disease outside the intestine are known as extraintestinal pathogenic E. coli (ExPEC) and include pathogens of humans and animals. Previously, the genome of avian-pathogenic E. coli (APEC) O1:K1:H7 strain O1, from ST95, was sequenced and compared to those of several other E. coli strains, identifying 43 genomic islands. Here, the genomic islands of APEC O1 were compared to those of other sequenced E. coli strains, and the distribution of 81 genes belonging to 12 APEC O1 genomic islands among 828 human and avian ExPEC and commensal E. coli isolates was determined. Multiple islands were highly prevalent among isolates belonging to the O1 and O18 serogroups within phylogenetic group B2, which are implicated in human neonatal meningitis. Because of the extensive genomic similarities between APEC O1 and other human ExPEC strains belonging to the ST95 phylogenetic lineage, its ability to cause disease in a rat model of sepsis and meningitis was assessed. Unlike other ST95 lineage strains, APEC O1 was unable to cause bacteremia or meningitis in the neonatal rat model and was significantly less virulent than uropathogenic E. coli (UPEC) CFT073 in a mouse sepsis model, despite carrying multiple neonatal meningitis E. coli (NMEC) virulence factors and belonging to the ST95 phylogenetic lineage. These results suggest that host adaptation or genome modifications have occurred either in APEC O1 or in highly virulent ExPEC isolates, resulting in differences in pathogenicity. Overall, the genomic islands examined provide targets for further discrimination of the different ExPEC subpathotypes, serogroups, phylogenetic types, and sequence types. PMID:22467781

Prevalence of avian-pathogenic Escherichia coli strain O1 genomic islands among extraintestinal and commensal E. coli isolates.

PubMed

Johnson, Timothy J; Wannemuehler, Yvonne; Kariyawasam, Subhashinie; Johnson, James R; Logue, Catherine M; Nolan, Lisa K

2012-06-01

Escherichia coli strains that cause disease outside the intestine are known as extraintestinal pathogenic E. coli (ExPEC) and include pathogens of humans and animals. Previously, the genome of avian-pathogenic E. coli (APEC) O1:K1:H7 strain O1, from ST95, was sequenced and compared to those of several other E. coli strains, identifying 43 genomic islands. Here, the genomic islands of APEC O1 were compared to those of other sequenced E. coli strains, and the distribution of 81 genes belonging to 12 APEC O1 genomic islands among 828 human and avian ExPEC and commensal E. coli isolates was determined. Multiple islands were highly prevalent among isolates belonging to the O1 and O18 serogroups within phylogenetic group B2, which are implicated in human neonatal meningitis. Because of the extensive genomic similarities between APEC O1 and other human ExPEC strains belonging to the ST95 phylogenetic lineage, its ability to cause disease in a rat model of sepsis and meningitis was assessed. Unlike other ST95 lineage strains, APEC O1 was unable to cause bacteremia or meningitis in the neonatal rat model and was significantly less virulent than uropathogenic E. coli (UPEC) CFT073 in a mouse sepsis model, despite carrying multiple neonatal meningitis E. coli (NMEC) virulence factors and belonging to the ST95 phylogenetic lineage. These results suggest that host adaptation or genome modifications have occurred either in APEC O1 or in highly virulent ExPEC isolates, resulting in differences in pathogenicity. Overall, the genomic islands examined provide targets for further discrimination of the different ExPEC subpathotypes, serogroups, phylogenetic types, and sequence types.

Age-related susceptibility to infection with diarrheagenic E. coli in infants from peri-urban areas of Lima, Peru

PubMed Central

Ochoa, Theresa J.; Ecker, Lucie; Barletta, Francesca; Mispireta, Mónica L.; Gil, Ana I.; Contreras, Carmen; Molina, Margarita; Amemiya, Isabel; Verastegui, Hector; Hall, Eric R.; Cleary, Thomas G.; Lanata, Claudio F.

2009-01-01

Background Diarrheagenic E. coli are being recognized as important pediatric enteropathogens worldwide. However, it is unclear whether there are differences in age-related susceptibility to specific agents, especially among infants. Methods We conducted a passive surveillance diarrhea cohort study of 1034 children from 2 to 12 months of age in Lima, Perú. Control stool samples were collected from randomly selected children without diarrhea. All samples were analyzed for common enteric pathogens and for the diarrheagenic E. coli by a multiplex real-time PCR. Results The most commonly isolated pathogens from 1065 diarrheal episodes were the diarrheagenic E. coli (31%), including enteroaggregative (15.1%) and enteropathogenic E. coli (EPEC) (7.6%). Diarrheagenic E. coli, Campylobacter and rotavirus were more frequently isolated from infants ≥ 6m. Diffusely adherent E. coli and enterotoxigenic E. coli (ETEC) were more frequently isolated in diarrheal samples than in controls in older infants (p<0.05). Children ≥ 6m infected with ETEC had a 4.56-fold increased risk for diarrhea (95% CI, 1.20 to 17.28). Persistent diarrhea was more frequent in infants < 6m (13.5% vs. 3.6%, p<0.001). Among diarrheagenic E. coli positive samples, co-infections with other pathogens were more common in diarrhea than in controls (40.1% vs. 15.6%, p<0.001). Conclusions Diarrheagenic E. coli were more frequently isolated in older infants. In this setting with high frequency of pathogen exposure and high frequency of breastfeeding, we hypothesize that the major age-related differences result from decreased exposure to milk protective factors and with increased exposure to contaminated food and water. PMID:19857163

Prevalence and behavior of multidrug-resistant shiga toxin-producing Escherichia coli, enteropathogenic E. coli and enterotoxigenic E. coli on coriander.

PubMed

Gómez-Aldapa, Carlos A; Segovia-Cruz, Jesús A; Cerna-Cortes, Jorge F; Rangel-Vargas, Esmeralda; Salas-Rangel, Laura P; Gutiérrez-Alcántara, Eduardo J; Castro-Rosas, Javier

2016-10-01

The prevalence and behavior of multidrug-resistant diarrheagenic Escherichia coli pathotypes on coriander was determined. One hundred coriander samples were collected from markets. Generic E. coli were determined using the most probable number procedure. Diarrheagenic E. coli pathotypes (DEPs) were identified using two multiplex polymerase chain reaction procedures. Susceptibility to sixteen antibiotics was tested for the isolated DEPs strains by standard test. The behavior of multidrug-resistant DEPs isolated from coriander was determined on coriander leaves and chopped coriander at 25°± 2 °C and 3°± 2 °C. Generic E. coli and DEPs were identified, respectively, in 43 and 7% of samples. Nine DEPs strains were isolated from positive coriander samples. The identified DEPs included Shiga toxin-producing E. coli (STEC, 4%) enterotoxigenic E. coli (ETEC, 2%) and enteropathogenic E. coli (EPEC, 1%). All isolated DEPs strains exhibited multi-resistance to antibiotics. On inoculated coriander leaves stored at 25°± 2 °C or 3°± 2 °C, no growth was observed for multidrug-resistant DEPs strains. However, multidrug-resistant DEPs strains grew in chopped coriander: after 24 h at 25° ± 2 °C, DEPs strains had grown to approximately 3 log CFU/g. However, at 3°± 2 °C the bacterial growth was inhibited. To the best of our knowledge, this is the first report of the presence and behavior of multidrug-resistant STEC, ETEC and EPEC on coriander and chopped coriander. Copyright © 2016 Elsevier Ltd. All rights reserved.

Isolation and characterization of Escherichia coli pathotypes and factors associated with well and boreholes water contamination in Mombasa County

PubMed Central

Thani, Thani Suleiman; Symekher, Samwel Morris Lifumo; Boga, Hamadi; Oundo, Joseph

2016-01-01

Introduction Safe water for human consumption is important, but there is a limited supply. Mombasa County has water shortages making residences rely on other sources of water including boreholes and wells. Microbiological evaluation of drinking water is important to reduce exposure to water borne enteric diseases. This cross sectional study aimed at determining the frequency and characterization of Escherichia coli (E. coli) pathotypes from water samples collected from wells and boreholes in Mombasa County. Methods One hundred and fifty seven (157) water samples were collected from four divisions of the county and a questionnaire administered. The samples were inoculated to double strength MacConkey broth and incubated at 370C for up to 48 hours. Positive results were compared to the 3 tube McCrady MPN table. The E. coli were confirmed by Eijkman's test and antibiotic susceptibility carried out. Using polymerase chain reaction (PCR), the E. coli were characterized to establish pathotypes. Results One hundred and thirty one (n = 131; 83.4%) samples had coliform bacteria with only 79 (60.3%) samples having E. coli. Significant values (<0.05) were noted when coliforms were compared to variables with E. Coli showing no significance when compared to similar variables. E. coli (n = 77; 100%) tested were sensitive to Gentamicin, while all (n = 77; 100%) isolates were resistant to Ampicillin. PCR typed isolates as enteroinvasive E. Coli (EIEC). Conclusion Findings suggest that coliforms and E. coli are major contaminants of wells and boreholes in Mombasa County. The isolates have a variety of resistant and sensitivity patterns to commonly used antibiotics. PMID:27200121

Effects of feeding pasteurized waste milk to dairy calves on phenotypes and genotypes of antimicrobial resistance in fecal Escherichia coli isolates before and after weaning.

PubMed

Maynou, G; Migura-Garcia, L; Chester-Jones, H; Ziegler, D; Bach, A; Terré, M

2017-10-01

The aim of this study was to evaluate the effects of feeding pasteurized waste milk (pWM) to calves on antimicrobial resistance of fecal Escherichia coli at both phenotypic and genotypic levels. Fifty-two Holstein female calves (3 ± 1.3 d of age) were fed 1 of the 2 different types of milk: milk replacer (MR) without antimicrobials or pWM with β-lactam residues until weaning at 49 d of age. Fecal swabs of all calves were obtained on d 0, 35, and 56 of the study and 3 E. coli isolates per sample were studied. Phenotypic resistance was tested by the disk diffusion method against a panel of 12 antimicrobials. A total of 13 resistance genes consisting of β-lactam, sulfonamide, tetracycline, and aminoglycoside families were examined by PCR. Feeding pWM to calves increased the presence of phenotypic resistance to ampicillin, cephalotin, ceftiofur, and florfenicol in fecal E. coli compared with MR-fed calves. However, the presence of resistance to sulfonamides, tetracyclines, and aminoglycosides was common in dairy calves independent of their milk-feeding source, suggesting other factors apart from the feeding source are involved in the emergence of antimicrobial resistance. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Genomic Comparisons and Shiga Toxin Production among Escherichia coli O157:H7 Isolates from a Day Care Center Outbreak and Sporadic Cases in Southeastern Wisconsin

PubMed Central

Gouveia, S.; Proctor, M. E.; Lee, M.-S.; Luchansky, J. B.; Kaspar, C. W.

1998-01-01

Contour-clamped homogeneous electric field pulsed-field gel electrophoresis (CHEF-PFGE) was used to compare Wisconsin isolates of Escherichia coli O157:H7, including 39 isolates from a 1994 day care center outbreak, 28 isolates from 18 individuals from the surrounding geographic area with sporadic cases occurring during the 3 months before the outbreak, and 3 isolates, collected in 1995, from patients with hemolytic-uremic syndrome (HUS) who were from eastern Wisconsin counties other than those inhabited by the day care center and sporadic-case individuals. The technique of CHEF-PFGE using XbaI identified seven highly related restriction endonuclease digestion profiles (REDPs) (93 to 98% similarity) among the 39 day care center isolates and nine XbaI REDPs (63 to 93% similarity) among the 28 isolates from sporadic-case individuals, including REDP 33, which was exhibited by both day care and sporadic-case isolates. PFGE analyses of sequential E. coli O157:H7 isolates from symptomatic day care center attendees revealed that the REDPs of 25 isolates from eight patients were indistinguishable whereas the REDPs of 2 of 6 isolates from two patients differed slightly (93 to 95% similarity). The REDPs of the three isolates from 1995 HUS patients were 78 to 83% similar, with REDP 26 being exhibited by one HUS-associated isolate and an isolate from one day care attendee who did not develop HUS. The genes for both Shiga toxins I and II (stx1 and stx2, respectively) were detected in all but one isolate (sporadic case), and Shiga toxin production by the day care center isolates was not significantly different from that of the other isolates, including the three HUS-associated isolates. Analyses of E. coli O157:H7 isolates from both the day care center outbreak and sporadic cases by CHEF-PFGE permitted us to define the REDP variability of an outbreak and geographic region and demonstrated that the day care center outbreak and a HUS case in 1995 were caused by E. coli O157:H7 strains endemic to eastern Wisconsin. PMID:9508303

Detection of diarrheagenic Escherichia coli strains isolated from dogs and cats in Brazil.

PubMed

Puño-Sarmiento, Juan; Medeiros, Leonardo; Chiconi, Carolina; Martins, Fernando; Pelayo, Jacinta; Rocha, Sérgio; Blanco, Jorge; Blanco, Miguel; Zanutto, Marcelo; Kobayashi, Renata; Nakazato, Gerson

2013-10-25

Escherichia coli are gut microbiota bacteria that can cause disease in some humans and other animals, including dogs and cats that humans often keep as pets. Diarrheagenic E. coli (DEC) strains are classified into six categories: enteropathogenic (EPEC), enterotoxigenic (ETEC), Shiga toxin-producing (STEC), enteroinvasive (EIEC), enteroaggregative (EAEC), and diffuse-adhering E. coli (DAEC). In this study 144 and 163 E. coli colonies were isolated from the fecal samples of 50 dogs and 50 cats, respectively, with and without diarrhea from a Veterinary Hospital (clinical isolates). The virulence factors were determined using multiplex Polymerase Chain Reaction. Adherence assays, antibacterial susceptibility and serotyping (somatic or flagellar antigens) were performed on DEC isolates. We found 25 (17.4%) and 4 (2.5%) DEC strains isolated from dogs and cats, respectively. Only the EPEC and EAEC pathotypes were found in both animals. Meanwhile, genes from other pathotypes (STEC, EIEC, and ETEC) were not found in these clinical isolates. All of the DEC strains showed mannose-resistant adherence to HEp-2 and HeLa cells, and aggregative adherence was predominant in these isolates. Multiresistant strains to antimicrobials were found in most DEC strains including usual and unusual antimicrobials in veterinary practices. The serotypes of these DEC isolates were variable. The ONT serotype was predominant in these isolates. Some serotypes found in our study were described to human DEC. Here, we demonstrate that pets carry virulent DEC genes, which are mainly strains of EPECs and EAECs. The presence of these virulence factors in isolates from animals without diarrhea suggests that pets can act as a reservoir for human infection. Copyright © 2013 Elsevier B.V. All rights reserved.

Prevalence and Virulence Factors of Escherichia coli Serogroups O26, O103, O111, and O145 Shed by Cattle in Scotland

PubMed Central

Pearce, M. C.; Evans, J.; McKendrick, I. J.; Smith, A. W.; Knight, H. I.; Mellor, D. J.; Woolhouse, M. E. J.; Gunn, G. J.; Low, J. C.

2006-01-01

A national survey was conducted to determine the prevalence of Escherichia coli O26, O103, O111, and O145 in feces of Scottish cattle. In total, 6,086 fecal pats from 338 farms were tested. The weighted mean percentages of farms on which shedding was detected were 23% for E. coli O26, 22% for E. coli O103, and 10% for E. coli O145. The weighted mean prevalences in fecal pats were 4.6% for E. coli O26, 2.7% for E. coli O103, and 0.7% for E. coli O145. No E. coli O111 was detected. Farms with cattle shedding E. coli serogroup O26, O103, or O145 were widely dispersed across Scotland and were identified most often in summer and autumn. However, on individual farms, fecal shedding of E. coli O26, O103, or O145 was frequently undetectable or the numbers of pats testing positive were small. For serogroup O26 or O103 there was clustering of positive pats within management groups, and the presence of an animal shedding one of these serogroups was a positive predictor for shedding by others, suggesting local transmission of infection. Carriage of vtx was rare in E. coli O103 and O145 isolates, but 49.0% of E. coli O26 isolates possessed vtx, invariably vtx1 alone or vtx1 and vtx2 together. The carriage of eae and ehxA genes was highly associated in all three serogroups. Among E. coli serogroup O26 isolates, 28.9% carried vtx, eae, and ehxA—a profile consistent with E. coli O26 strains known to cause human disease. PMID:16391103

Detection and molecular characterization of Escherichia coli CTX-M-15 and Klebsiella pneumoniae SHV-12 β-lactamases from bovine mastitis isolates in the United Kingdom.

PubMed

Timofte, Dorina; Maciuca, Iuliana E; Evans, Nicholas J; Williams, Helen; Wattret, Andrew; Fick, Jenny C; Williams, Nicola J

2014-01-01

Recent reports raised concerns about the role that farm stock may play in the dissemination of extended-spectrum β-lactamase (ESBL)-producing bacteria. This study characterized the ESBLs in two Escherichia coli and three Klebsiella pneumoniae subsp. pneumoniae isolates from cases of clinical bovine mastitis in the United Kingdom. Bacterial culture and sensitivity testing of bovine mastitic milk samples identified Gram-negative cefpodoxime-resistant isolates, which were assessed for their ESBL phenotypes. Conjugation experiments and PCR-based replicon typing (PBRT) were used for characterization of transferable plasmids. E. coli isolates belonged to sequence type 88 (ST88; determined by multilocus sequence typing) and carried blaCTX-M-15 and blaTEM-1, while K. pneumoniae subsp. pneumoniae isolates carried blaSHV-12 and blaTEM-1. Conjugation experiments demonstrated that blaCTX-M-15 and blaTEM-1 were carried on a conjugative plasmid in E. coli, and PBRT identified this to be an IncI1 plasmid. The resistance genes were nontransferable in K. pneumoniae subsp. pneumoniae isolates. Moreover, in the E. coli isolates, an association of ISEcp1 and IS26 with blaCTX-M-15 was found where the IS26 element was inserted upstream of both ISEcp1 and the blaCTX-M promoter, a genetic arrangement highly similar to that described in some United Kingdom human isolates. We report the first cases in Europe of bovine mastitis due to E. coli CTX-M-15 and also of bovine mastitis due to K. pneumoniae subsp. pneumoniae SHV-12 β-lactamases in the United Kingdom. We also describe the genetic environment of blaCTX-M-15 and highlight the role that IncI1 plasmids may play in the spread and dissemination of ESBL genes, which have been described in both human and cattle isolates.

Detection and Molecular Characterization of Escherichia coli CTX-M-15 and Klebsiella pneumoniae SHV-12 β-Lactamases from Bovine Mastitis Isolates in the United Kingdom

PubMed Central

Maciuca, Iuliana E.; Evans, Nicholas J.; Williams, Helen; Wattret, Andrew; Fick, Jenny C.; Williams, Nicola J.

2014-01-01

Recent reports raised concerns about the role that farm stock may play in the dissemination of extended-spectrum β-lactamase (ESBL)-producing bacteria. This study characterized the ESBLs in two Escherichia coli and three Klebsiella pneumoniae subsp. pneumoniae isolates from cases of clinical bovine mastitis in the United Kingdom. Bacterial culture and sensitivity testing of bovine mastitic milk samples identified Gram-negative cefpodoxime-resistant isolates, which were assessed for their ESBL phenotypes. Conjugation experiments and PCR-based replicon typing (PBRT) were used for characterization of transferable plasmids. E. coli isolates belonged to sequence type 88 (ST88; determined by multilocus sequence typing) and carried blaCTX-M-15 and blaTEM-1, while K. pneumoniae subsp. pneumoniae isolates carried blaSHV-12 and blaTEM-1. Conjugation experiments demonstrated that blaCTX-M-15 and blaTEM-1 were carried on a conjugative plasmid in E. coli, and PBRT identified this to be an IncI1 plasmid. The resistance genes were nontransferable in K. pneumoniae subsp. pneumoniae isolates. Moreover, in the E. coli isolates, an association of ISEcp1 and IS26 with blaCTX-M-15 was found where the IS26 element was inserted upstream of both ISEcp1 and the blaCTX-M promoter, a genetic arrangement highly similar to that described in some United Kingdom human isolates. We report the first cases in Europe of bovine mastitis due to E. coli CTX-M-15 and also of bovine mastitis due to K. pneumoniae subsp. pneumoniae SHV-12 β-lactamases in the United Kingdom. We also describe the genetic environment of blaCTX-M-15 and highlight the role that IncI1 plasmids may play in the spread and dissemination of ESBL genes, which have been described in both human and cattle isolates. PMID:24247146

Molecular characteristic of mcr-1 producing Escherichia coli in a Chinese university hospital.

PubMed

He, Qing-Wen; Xu, Xiao-Hong; Lan, Fang-Jun; Zhao, Zhi-Chang; Wu, Zhi-Yun; Cao, Ying-Ping; Li, Bin

2017-04-19

Colistin has been considered as a last-line treatment option in severe infections caused by multidrug-resistant (MDR) gram-negative pathogens. However, the emergence of the mobile colistin resistance gene (mcr-1) has challenged this viewpoint. The aim of this study is to explore the prevalence of mcr-1 in Escherichia coli (E. coli) in a Chinese teaching hospital, and investigate their molecular characteristics. A total of 700 E. coli isolates were used to screen mcr-1 by PCR and sequencing in a Chinese university hospital from August 2014 to August 2015. Susceptibility test of mcr-1-producing isolates was determined by Vitek -2 Compact system. 26 virulence factors (VFs), phylogenetic groups, Multi-locus sequence typing (MLST), and DNA Fingerprinting (ERIC-PCR) of strains were investigated by PCR. Four (0.6%) mcr-1 producing E. coli isolates were found in this study. The results of antibiotic susceptibility test showed that all four isolates were resistant to colistin, ciprofloxacin, levofloxacin, cefazolin, and trimethoprim/sulfamethoxazole, and were susceptible to amikacin, ertapenem and imipenem. In addition, all 4 isolates exhibited high-level resistance to aztreonam, cefotaxime and gentamicin. The numbers of VFs contained in mcr-1 positive isolates were no more than 4 in our study. MLST result demonstrated that these isolates were assigned to two sequence types: ST156 and ST167. The result of phylogenetic analysis showed that four mcr-1-positive isolates belong to two phylogenetic groups: A and B1 group. ERIC-PCR showed that four mcr-1 positive strains were categorized into three different genotypes. Our study demonstrated a low prevalence of mcr-1 in E. coli clinical isolates in a Chinese teaching hospital, and we have gained insights into the molecular characteristics of these mcr-1-positive strains. Increasing the surveillance of these infections, as well as taking effective infection control measures are urgently needed to take to control the transmission of mcr-1 gene.

Escherichia coli Sequence Type 131 (ST131) Subclone H30 as an Emergent Multidrug-Resistant Pathogen Among US Veterans

PubMed Central

Colpan, Aylin; Johnston, Brian; Porter, Stephen; Clabots, Connie; Anway, Ruth; Thao, Lao; Kuskowski, Michael A.; Tchesnokova, Veronika; Sokurenko, Evgeni V.; Johnson, James R.; Allen, Bradley L.; Baracco, Gio J.; Bedimo, Roger; Bessesen, Mary; Bonomo, Robert A.; Brecher, Stephen M.; Brown, Sheldon T.; Castellino, Laila; Desai, Arundhati S.; Fernau, Fletcher; Fisher, Mark A.; Fleckenstein, James; Fleming, Carol S.; Fries, Narla J.; Kan, Virginia L.; Kauffman, Carol A.; Klutts, Stacey; Ohl, Michael; Russo, Thomas; Swiatlo, Andrea; Swiatlo, Edwin

2013-01-01

Background. Escherichia coli sequence type 131 (ST131), typically fluoroquinolone-resistant (FQ-R) and/or extended-spectrum β-lactamase (ESBL)–producing, has emerged globally. We assessed its prevalence and characteristics among US veterans. Methods. In 2011, 595 de-identified E. coli clinical isolates were collected systematically within 3 resistance groups (FQ-susceptible [FQ-S], FQ-R, and ESBL-producing) from 24 nationally distributed Veterans Affairs Medical Centers (VAMCs). ST131 and its H30 subclone were detected by polymerase chain reaction and compared with other E. coli for molecular traits, source, and resistance profiles. Results. ST131 accounted for 78% (184/236) of FQ-R and 64.2% (79/123) of ESBL-producing isolates, but only 7.2% (17/236) of FQ-S isolates (P < .001). The H30 subclone accounted for ≥95% of FQ-R and ESBL-producing, but only 12.5% of FQ-S, ST131 isolates (P < .001). By back-calculation, 28% of VAMC E. coli isolates nationally represented ST131. Overall, ST131 varied minimally in prevalence by specimen type, inpatient/outpatient source, or locale; was the most prevalent ST, followed distantly by ST95 and ST12 (13% each); and accounted for ≥40% (β-lactams), >50% (trimethoprim-sulfamethoxazole , multidrug), or >70% (ciprofloxacin, gentamicin) of total antimicrobial resistance. FQ-R and ESBL-producing ST131 isolates had higher virulence scores than corresponding non-ST131 isolates. ST131 pulsotypes overlapped extensively among VAMCs. Conclusions. Among US veterans, ST131, primarily its H30 subclone, accounts for most antimicrobial-resistant E. coli and is the dominant E. coli strain overall. Possible contributors include multidrug resistance, extensive virulence gene content, and ongoing transmission. Focused attention to ST131, especially its H30 subclone, could reduce infection-related morbidity, mortality, and costs among veterans. PMID:23926176

Genotypic Characterization of Egypt Enterotoxigenic Escherichia coli Isolates Expressing Coli Surface Antigen 6

DTIC Science & Technology

2013-02-01

47%) of these isolates were resistant to ampicillin, a third (37%) of the isolates were resistant to trimethoprim -sulfamethoxazole, and 24% of the...isolates were tetracycline-resistant. A blaTEM gene was detected in 24 (83%) ampicillin-resistant isolates. Trimethoprim -sulfamethoxazole-resistant...ciprofloxacin (CIP) 5 μg, amikacin (AN) 30 μg, gentamicin (GEN) 10 μg, tetracycline (TET) 30 μg, trimethoprim 1.25 μg / sulfamethoxazole 23.75 μg (SXT

Comparative Genomics of Recent Shiga Toxin-Producing Escherichia coli O104:H4: Short-Term Evolution of an Emerging Pathogen

PubMed Central

Grad, Yonatan H.; Godfrey, Paul; Cerquiera, Gustavo C.; Mariani-Kurkdjian, Patricia; Gouali, Malika; Bingen, Edouard; Shea, Terrence P.; Haas, Brian J.; Griggs, Allison; Young, Sarah; Zeng, Qiandong; Lipsitch, Marc; Waldor, Matthew K.; Weill, François-Xavier; Wortman, Jennifer R.; Hanage, William P.

2013-01-01

ABSTRACT The large outbreak of diarrhea and hemolytic uremic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli O104:H4 in Europe from May to July 2011 highlighted the potential of a rarely identified E. coli serogroup to cause severe disease. Prior to the outbreak, there were very few reports of disease caused by this pathogen and thus little known of its diversity and evolution. The identification of cases of HUS caused by E. coli O104:H4 in France and Turkey after the outbreak and with no clear epidemiological links raises questions about whether these sporadic cases are derived from the outbreak. Here, we report genome sequences of five independent isolates from these cases and results of a comparative analysis with historical and 2011 outbreak isolates. These analyses revealed that the five isolates are not derived from the outbreak strain; however, they are more closely related to the outbreak strain and each other than to isolates identified prior to the 2011 outbreak. Over the short time scale represented by these closely related organisms, the majority of genome variation is found within their mobile genetic elements: none of the nine O104:H4 isolates compared here contain the same set of plasmids, and their prophages and genomic islands also differ. Moreover, the presence of closely related HUS-associated E. coli O104:H4 isolates supports the contention that fully virulent O104:H4 isolates are widespread and emphasizes the possibility of future food-borne E. coli O104:H4 outbreaks. PMID:23341549

Genomic landscape of extended-spectrum β-lactamase resistance in Escherichia coli from an urban African setting.

PubMed

Musicha, Patrick; Feasey, Nicholas A; Cain, Amy K; Kallonen, Teemu; Chaguza, Chrispin; Peno, Chikondi; Khonga, Margaret; Thompson, Sarah; Gray, Katherine J; Mather, Alison E; Heyderman, Robert S; Everett, Dean B; Thomson, Nicholas R; Msefula, Chisomo L

2017-06-01

Efforts to treat Escherichia coli infections are increasingly being compromised by the rapid, global spread of antimicrobial resistance (AMR). Whilst AMR in E. coli has been extensively investigated in resource-rich settings, in sub-Saharan Africa molecular patterns of AMR are not well described. In this study, we have begun to explore the population structure and molecular determinants of AMR amongst E. coli isolates from Malawi. Ninety-four E. coli isolates from patients admitted to Queen's Hospital, Malawi, were whole-genome sequenced. The isolates were selected on the basis of diversity of phenotypic resistance profiles and clinical source of isolation (blood, CSF and rectal swab). Sequence data were analysed using comparative genomics and phylogenetics. Our results revealed the presence of five clades, which were strongly associated with E. coli phylogroups A, B1, B2, D and F. We identified 43 multilocus STs, of which ST131 (14.9%) and ST12 (9.6%) were the most common. We identified 25 AMR genes. The most common ESBL gene was bla CTX-M-15 and it was present in all five phylogroups and 11 STs, and most commonly detected in ST391 (4/4 isolates), ST648 (3/3 isolates) and ST131 [3/14 (21.4%) isolates]. This study has revealed a high diversity of lineages associated with AMR, including ESBL and fluoroquinolone resistance, in Malawi. The data highlight the value of longitudinal bacteraemia surveillance coupled with detailed molecular epidemiology in all settings, including low-income settings, in describing the global epidemiology of ESBL resistance. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Analysis of blaCTX-M-Carrying Plasmids from Escherichia coli Isolates Collected in the BfT-GermVet Study ▿

PubMed Central

Schink, Anne-Kathrin; Kadlec, Kristina; Schwarz, Stefan

2011-01-01

In this study, 417 Escherichia coli isolates from defined disease conditions of companion and farm animals collected in the BfT-GermVet study were investigated for the presence of extended-spectrum β-lactamase (ESBL) genes. Three ESBL-producing E. coli isolates were identified among the 100 ampicillin-resistant isolates. The E. coli isolates 168 and 246, of canine and porcine origins, respectively, harbored blaCTX-M-1, and the canine isolate 913 harbored blaCTX-M-15, as confirmed by PCR and sequence analysis. The isolates 168 and 246 belonged to the novel multilocus sequence typing (MLST) types ST1576 and ST1153, respectively, while isolate 913 had the MLST type ST410. The ESBL genes were located on structurally related IncN plasmids in isolates 168 and 246 and on an IncF plasmid in isolate 913. The blaCTX-M-1 upstream regions of plasmids pCTX168 and pCTX246 were similar, whereas the downstream regions showed structural differences. The genetic environment of the blaCTX-M-15 gene on plasmid pCTX913 differed distinctly from that of both blaCTX-M-1 genes. Detailed sequence analysis showed that the integration of insertion sequences, as well as interplasmid recombination events, accounted for the structural variability in the blaCTX-M gene regions. PMID:21685166