Science.gov

Sample records for escherichia coli isolated

  1. TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE IN SEWAGE ISOLATES OF ESCHERICHIA COLI

    EPA Science Inventory

    Sewage samples from seven locations in the United States were analyzed for Escherichia coli isolates which were resistant to trimethoprim-sulfamethoxazole (SXT). The prevalence rate of SXT resistant organisms varied between the different geographical locales. The majority of th...

  2. TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE IN SEWAGE ISOLATES OF ESCHERICHIA COLI

    EPA Science Inventory

    Sewage samples from seven locations in the United States were analyzed for Escherichia coli isolates which were resistant to trimethoprim-sulfamethoxazole (SXT). The prevalence rate of SXT resistant organisms varied between the different geographical locales. The majority of th...

  3. 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

  4. TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE IN SEWAGE ISOLATES OF ESCHERICHIA COLI

    EPA Science Inventory

    The increase in resistance rates to trimehtoprim-sulfamethoxazole (TMP/SMX) in isolates of Escherichia coli has become a matter of increasing concern. This has been particularly true in reference to community acquired urinary tract infections (UTI). This study utilized sewage i...

  5. TRIMETHOPRIM-SULFAMETHOXAZOLE RESISTANCE IN SEWAGE ISOLATES OF ESCHERICHIA COLI

    EPA Science Inventory

    The increase in resistance rates to trimehtoprim-sulfamethoxazole (TMP/SMX) in isolates of Escherichia coli has become a matter of increasing concern. This has been particularly true in reference to community acquired urinary tract infections (UTI). This study utilized sewage i...

  6. Isolation of an Lc-specific Escherichia coli bacteriophage.

    PubMed Central

    Fralick, J A; Diedrich, D L; Casey-Wood, S

    1990-01-01

    We isolated an OmpF-specific bacteriophage whose host range mutant, SQ108h2, requires the presence of the Lc porin for its attachment and which can be used to screen or select for Lc-defective mutants among Escherichia coli K-12 strains lysogenic for the PA-2 converting phage. Images FIG. 1 PMID:1689719

  7. Norfloxacin resistance in a clinical isolate of Escherichia coli.

    PubMed Central

    Aoyama, H; Sato, K; Kato, T; Hirai, K; Mitsuhashi, S

    1987-01-01

    Analysis of DNA gyrase supercoiling and of norfloxacin uptake in Escherichia coli GN14176, a moderately norfloxacin-resistant clinical isolate, indicated that resistance was associated with both an altered drug target and a reduction in drug uptake. Images PMID:2829712

  8. [Drug resistance of Escherichia coli strains isolated from poultry].

    PubMed

    Giurov, B; Korudzhiĭski, N; Bineva, I

    1981-01-01

    Studied was the sensitivity of a total of 143 strains of Escherichia coli, isolated from young birds and broilers died from coli septicaemia, to antibiotics and chemotherapeutics. The following descending order was established: gentamycin, carbenicillin, ampicillin, furazolidon, borgal, kanamycin, strep tomycin, chloramphenicol, neomycin sulphathiazole, and tetracycline. Markers of resistance were established with all strains with regard to the therapeutic agents in current and prospective use in industrial poultry farming. It is stated that a preliminary antibiogram is indispensable in order to obtain dependable results in the treatment of animals affected with colibacteriosis. An alternative is to apply directly those drugs to which the strains have shown highest sensitivity.

  9. Resistance and virulence factors of Escherichia coli isolated from chicken.

    PubMed

    Pavlickova, Silvie; Dolezalova, Magda; Holko, Ivan

    2015-01-01

    Chicken meat has become an important part of the human diet and besides contamination by pathogenic Escherichia coli there is a risk of antibiotic resistance spreading via the food chain. The purpose of this study was to examine the prevalence of resistance against eight antibiotics and the presence of 14 virulence factors among 75 Escherichia coli strains isolated from chicken meat in the Czech Republic after classification into phylogenetic groups by the multiplex PCR method. More than half of strains belonged to A phylogroup, next frequently represented was B1 phylogroup, which suggests the commensal strains. The other strains were classified into phylogroups B2 and D, which had more virulence factors. Almost half of all E. coli strains were resistant to at least one of eight-tested antibiotics. A multidrug resistance was observed in 13% of strains. The most prevalent virulence genes were iucD, iss and tsh. None of genes encoding toxins was detected. Most of E. coli strains isolated from chicken meat can be considered as nonpathogenic on the basis of analysis of virulence factors, antibiotic resistance and phylogroups assignment. It can provide a useful tool for prediction of a potential risk from food contaminated by E. coli.

  10. Infectious Drug Resistance Among Clinically Isolated Escherichia coli

    PubMed Central

    Gunter, Ann C.; Feary, Thomas W.

    1968-01-01

    Of 398 strains of clinically isolated Escherichia coli from three Birmingham, Alabama, hospitals, 38% were found to be resistant to one or more drugs tested. Fifty-seven per cent of the resistant strains transferred all or a part of their resistance pattern to sensitive cells during mixed cultivation. Of the 152 resistant strains, 29.1% were singly resistant, and 70.5% were resistant to more than one drug. Of the multiply resistant strains, 61% transferred all or a part of their pattern. Strains isolated from Veterans Hospital patients demonstrated higher percentages of resistance than strains isolated from Children's Hospital patients. An extremely low incidence of infective drug resistance was noted among E. coli isolated from the stools of healthy hospital employees. PMID:4882016

  11. [Antimicrobial susceptibility of Escherichia coli isolates from river water ecosystems].

    PubMed

    Romeu Alvarez, Beatriz; Salazar Jiménez, Paloma; Lugo Moya, Daysi; Rojas Hernández, Nidia M; Eslava Campos, Carlos A

    2012-01-01

    Antimicrobial resistance is one of the biggest problems facing global public health. The emergence of resistant clinical and environmental strains worsens the situation. Among the microorganisms with antimicrobial resistance, Escherichia coil species stands out due to its dual role as fecal contamination indicator and pathogen. To isolate and identify Escherichia coil isolates from water samples from polluted rivers located in La Habana, and to determine their antimicrobial in vitro susceptibility. One hundred thirteen isolates of coliform bacteria isolated from 10 sampling stations in the capital's urban areas near Almendares, Quibú and Luyanó rivers were studied in the period of February 2008 to June 2010. The identification of isolates, the determination of antimicrobial susceptibility and the search for extended-spectrum beta-lactamase were all performed using VITEK automated method. One hundred thirteen environmental strains of Escherichia coli were identified. It showed that 23% of the isolates were resistant to at least one of the tested antimicrobials. The highest percentages of resistance were observed to ampicilline, sulfamethoxazole-trimethoprim and ciprofloxacin. The presence of E. coil isolates with multiple antimicrobial resistances in these rivers clearly indicates the biological risk involving the use of their waters.

  12. Characterization of Shiga toxigenic Escherichia coli isolated from foods.

    PubMed

    Martínez, Aida Juliana; Bossio, Carolina Paba; Durango, Adriana Coral; Vanegas, Maria Consuelo

    2007-12-01

    The aim of this study was to characterize Shiga toxigenic Escherichia coli (STEC) by PCR using strains isolated from ham, beef, and cattle in Colombia. A total of 189 E. coli strains were tested for the presence of the uidA, stx1, and stx2 genes, and identification was confirmed by the automated PCR BAX system for E. coli O157:H7. Genes encoding Shiga-like toxins (stx) were found in eight (6.06%) of 132 strains previously isolated from minced beef; four (50%) of these strains yielded amplification products for both toxin genes (stx1 and stx2), and four (50%) yielded products only for the stx2 toxin. None of the strains analyzed were positive by PCR for the presence of the single base-pair mutation in the uidA gene from E. coli O157:H7; these results were confirmed by the BAX system analysis. A multiplex PCR assay was standardized for the three genes. Results from this study confirmed previous data about the low prevalence of E. coli O157:H7 and Shiga-like toxins in Colombia and is the first known report of the prevalence of non-O157 enterohemorrhagic E. coli in this country.

  13. Antibiotic Resistance in Urinary Isolates of Escherichia coli

    PubMed Central

    Abduzaimovic, Amila; Aljicevic, Mufida; Rebic, Velma; Vranic, Sabina Mahmutovic; Abduzaimovic, Kadrija; Sestic, Sabina

    2016-01-01

    Objectives: The aim of this study was to examine the presence of antimicrobial resistance / susceptibility strains of Escherichia coli in inpatients and outpatients. Materials and methods: It is a retrospective study carried out at the Department of Microbiology, Parasitology and Virology Faculty of Medicine, University of Sarajevo. In cooperation with the Microbiological laboratory of the Cantonal Hospital Zenica and the Microbiological laboratory of the General Hospital Tesanj, 3863 urine samples were processed in the period from March 1st to March 31st 2016. Results: Our study showed that E. coli had the highest antimicrobial resistance to trimethoprim / sulfamethoxazole (38.61%), followed by amoxicillin / clavulanic acid (19.62%), ciprofloxacin (9.49%), gentamicin (8.86%), cephalexin (8.23%), nitrofurantoin (8.23%), cefuroxime (7.52%), ceftazidime (6.33%), cefuroxime (89.87%), amikacin (4.43%). Conclusions: The isolated strains of E. coli showed the highest resistance to trimethoprim / sulfamethoxazole and amoxicillin / clavulanic acid. The isolated strains of E. coli showed the greatest susceptibility to amikacin and ceftazidime. Gender distribution of positive E. coli isolates showed statistically significant differences in favor of females. PMID:28144190

  14. Gentamicin resistance among Escherichia coli strains isolated in neonatal sepsis.

    PubMed

    Hasvold, J; Bradford, L; Nelson, C; Harrison, C; Attar, M; Stillwell, T

    2013-01-01

    Neonatal sepsis is a significant cause of morbidity and mortality among term and preterm infants. Ampicillin and gentamicin are standard empiric therapy for early onset sepsis. Four cases of neonatal sepsis secondary to Escherichia coli (E. coli) found to be gentamicin resistant occurred within a five week period in one neonatal intensive care unit (NICU). To determine whether these cases could be tied to a single vector of transmission, and to more broadly evaluate the incidence of gentamicin resistant strains of E. coli in the neonatal population at our institution compared to other centers, we reviewed the charts of the four neonates (Infants A through D) and their mothers. The E. coli isolates were sent for Pulse Field Gel Electrophoresis (PFGE) to evaluate for genetic similarity between strains. We also reviewed all positive E. coli cultures from one NICU over a two year period. Infants A and B had genetically indistinguishable strains which matched that of urine and placental cultures of Infant B's mother. Infant C had a genetically distinct organism. Infant D, the identical twin of Infant C, did not have typing performed. Review of all cultures positive for E. coli at our institution showed a 12.9 percent incidence of gentamicin-resistance. A review of other studies showed that rates of resistance vary considerably by institution. We conclude that gentamicin-resistant E. coli is a relatively uncommon cause of neonatal sepsis, but should remain a consideration in patients who deteriorate despite initiation of empiric antibiotics.

  15. Isolation and mapping of phosphotransferase mutants in Escherichia coli.

    PubMed

    Epstein, W; Jewett, S; Fox, C F

    1970-11-01

    Mutants of Escherichia coli K-12 defective in enzyme I or Hpr, the two common components of the phosphoenolpyruvate-dependent phosphotransferase system, were isolated by a simple, direct method. The ptsI locus, the structural gene for enzyme I, and the ptsH locus, the site of mutations leading to loss of Hpr activity, are adjacent genes and could be part of a single operon. These two genes lie between the purC and supN markers in the order: strA... guaB-purC-ptsI-ptsH-supN-dsdA... his.

  16. Isolation and Mapping of Phosphotransferase Mutants in Escherichia coli

    PubMed Central

    Epstein, Wolfgang; Jewett, Susan; Fox, C. Fred

    1970-01-01

    Mutants of Escherichia coli K-12 defective in enzyme I or Hpr, the two common components of the phosphoenolpyruvate-dependent phosphotransferase system, were isolated by a simple, direct method. The ptsI locus, the structural gene for enzyme I, and the ptsH locus, the site of mutations leading to loss of Hpr activity, are adjacent genes and could be part of a single operon. These two genes lie between the purC and supN markers in the order: strA... guaB-purC-ptsI-ptsH-supN-dsdA... his. PMID:4923073

  17. Characterization of avian pathogenic Escherichia coli isolated in eastern China.

    PubMed

    Dou, Xinhong; Gong, Jiansen; Han, Xiangan; Xu, Ming; Shen, Haiyu; Zhang, Di; Zhuang, Linlin; Liu, Jiasheng; Zou, Jianmin

    2016-01-15

    In order to investigate the biological characteristics of avian pathogenic Escherichia coli (APEC) isolated in eastern China, a total of 243 isolates were isolated from diseased poultry on different farms during the period from 2007 to 2014. These isolates were characterized for serogroups (polymerase chain reaction and agglutination), the presence of virulence-associated genes (fimC, iss, ompA, fyuA, stx2f, iroC, iucD, hlyE, tsh, cvaC, irp2, and papC) and class I integrons (polymerase chain reaction), drug susceptibilities (disk diffusion method) and the biofilm-forming abilities (semi-quantitative method). The results showed that the most predominant serogroups were O78 (87 isolates, 35.8%) and O2 (35 isolates, 14.4%). Gene profiling found that fimC and ompA were frequently distributed among the isolates and that 77.4% of the isolates were positive for class 1 integrons. Overall, isolates displayed resistance to tetracycline (97.5%), nalidixic acid (82.3%), ampicillin (81.1%), sulphafurazole (80.7%), streptomycin (79.0%), trimethoprim (78.2%) and cotrimoxazole (78.2%). Multiple-drug resistance was exhibited in 80.3% of the isolates, and the presence of class 1 integrons is associated with multidrug resistance. Finally, 151 isolates had the ability to form biofilms in vitro, and drug resistance seemed relative to biofilm-forming abilities.

  18. Virulence and antibiotic resistance of Escherichia coli isolated from rooks.

    PubMed

    Kmet, Vladimir; Drugdova, Zuzana; Kmetova, Marta; Stanko, Michal

    2013-01-01

    With regard to antibiotic resistance studies in various model animals in the urban environment, the presented study focused on the rook, many behavioural and ecological aspects of which are important from an epidemiological point of view. A total of 130 Escherichia coli strains isolated from rook faeces during a two-year period (2011-2012) were investigated for antibiotic resistance and virulence. Resistance to ampicillin (60%) and streptomycin (40%) were the most frequent, followed by resistance to fluoroquinolones (ciprofloxacin-22% and enrofloxacin-24%), tetracycline (18%), cotrimoxazol (17%) and florfenicol (14%). Ceftiofur resistance occured in 10.7% of strains and cefquinom resistance in 1.5% of strains. Twenty-five E.coli strains with a higher level of MICs of cephalosporins (over 2mg/L of ceftazidime and ceftriaxon) and fluoroquinolones were selected for detection of betalactamase genes (CTX-M, CMY), plasmid-mediated quinolone resistance qnrS, integrase 1, and for APEC (avian pathogenic E.coli) virulence factors (iutA, cvaC, iss, tsh, ibeA, papC, kpsII). Genes of CTX-M1, CMY-2, integrase 1, papC, cvaC, iutA were detected in one strain of E.coli, and qnrS, integrase 1, iss, cvaC, tsh were detected in another E.coli. DNA microarray revealed the absence of verotoxin and enterotoxin genes and pathogenicity islands. The results show that rooks can serve as a reservoir of antibiotic-resistant E. coli with avian pathogenic virulence factors for the human population, and potentially transmit such E.coli over long distances.

  19. Clonal relationships among bloodstream isolates of Escherichia coli.

    PubMed

    Maslow, J N; Whittam, T S; Gilks, C F; Wilson, R A; Mulligan, M E; Adams, K S; Arbeit, R D

    1995-07-01

    The clonal relationships among 187 bloodstream isolates of Escherichia coli from 179 patients at Boston, Mass., Long Beach, Calif., and Nairobi, Kenya, were determined by multilocus enzyme electrophoresis (MLEE), analysis of polymorphisms associated with the ribosomal operon (ribotyping), and serotyping. MLEE based on 20 enzymes resolved 101 electrophoretic types (ETs), forming five clusters; ribotyping resolved 56 distinct patterns concordant with the analysis by MLEE. The isolates at each study site formed a genetically diverse group and demonstrated similar clonal structures, with the same small subset of lineages accounting for the majority of isolates at each site. Moreover, two ribotypes accounted for approximately 30% of the isolates at each study site. One cluster contained the majority (65%) of isolates and, by direct comparison of the ETs and ribotypes of individual isolates, was genetically indistinguishable from the largest cluster for each of two other collections of E. coli causing pyelonephritis and neonatal meningitis (R. K. Selander, T. K. Korhonen, V. Väisänen-Rhen, P. H. Williams, P. E. Pattison, and D. A. Caugent, Infect. Immun. 52:213-222, 1986; M. Arthur, C. E. Johnson, R. H. Rubin, R. D. Arbeit, C. Campanelli, C. Kim, S. Steinbach, M. Agarwal, R. Wilkinson, and R. Goldstein, Infect. Immun. 57:303-313, 1989), thus defining a virulent set of lineages. The isolates within these virulent lineages typically carried DNA homologous to the adhesin operon pap or sfa and the hemolysin operon hly and expressed O1, O2, O4, O6, O18, O25, or O75 antigens. DNA homologous to pap was distributed among isolates of each major cluster, whereas hly was restricted to isolates of two clusters, typically detected in pap-positive strains, and sfa was restricted to isolates of one cluster, typically detected in pap- and hly-positive strains. The occurrence of pap-positive isolates in the same geographically and genetically divergent lineages suggests that this

  20. Metalloendopeptidase QG. Isolation from Escherichia coli and characterization.

    PubMed

    Polgár, L; Szigetvári, A; Löw, M; Kóródi, I; Balla, E

    1991-02-01

    A new proteinase, which preferentially cleaves the Gln-Gly bond, was isolated from Escherichia coli. Because of this narrow specificity, the enzyme was called metalloendopeptidase QG. The proteinase is a monomer and consists of a single polypeptide chain of Mr 67,000, which is significantly smaller than the other known metalloendopeptidases of E. coli. It is found in the cytoplasm, but not in the periplasm. The enzyme cleaves the substrate benzyloxycarbonyl-Gln-Gly-Pro 2-naphthylamide between the glutamine and glycine residues, as well as its extended homologues including a nonapeptide, but it does not hydrolyse either the oxidized A and B chains of insulin or azo-casein. The pH-dependence of substrate hydrolysis gives a bell-shaped curve with pK1 = 6.6 and pK2 = 8.8. The metallopeptidase is inhibited in Tris and imidazole buffers, the basic components of which are presumably liganded to the essential Zn2+ ion. 2-Aminobenzoyl-Gln-Gly-Pro 2-naphthylamide, designed as a fluorescent substrate for the metallopeptidase, proved to be a strong inhibitor. Bestatin, an inhibitor of aminopeptidases in the micromolar concentration range, inhibits the metalloendopeptidase only in the millimolar concentration range. Captopril, the widely used inhibitor of angiotensin-converting enzyme, is a fairly good inhibitor of the metalloendopeptidase. The simplest inhibitor that can be used to protect recombinant proteins from degradation by the metalloendopeptidase may be EDTA, which is effective at low millimolar concentration.

  1. Escherichia Coli

    ERIC Educational Resources Information Center

    Goodsell, David S.

    2009-01-01

    Diverse biological data may be used to create illustrations of molecules in their cellular context. I describe the scientific results that support a recent textbook illustration of an "Escherichia coli cell". The image magnifies a portion of the bacterium at one million times, showing the location and form of individual macromolecules. Results…

  2. Escherichia Coli

    ERIC Educational Resources Information Center

    Goodsell, David S.

    2009-01-01

    Diverse biological data may be used to create illustrations of molecules in their cellular context. I describe the scientific results that support a recent textbook illustration of an "Escherichia coli cell". The image magnifies a portion of the bacterium at one million times, showing the location and form of individual macromolecules. Results…

  3. [Sensitivity to drugs of Escherichia coli strains isolated from poultry with coli septicemia].

    PubMed

    Giurov, B

    1985-01-01

    Investigations were carried out into the susceptibility of a total of 223 strains of Escherichia coli to therapeutic agents with the employment of the disk diffusion method. The organisms were isolated from internal organs and bone marrow of birds died of coli septicaemia. The serologic classification of the strains was defined with the use of 88 anti-group OK-agglutinating sera obtained through hyperimmunization of rabbits with the following Escherichia coli serotypes: 01-063, 068, 071, 073, 075, 078, 086, 0101, 0103, 0111-0114, 0119, 0124, 0129, 0135-0141, 0146, 0147, and 0149. It was found that serologically the strains referred as follows: 01-41 strains, 02-70 strains, 04-2 strains, 08-3 strains, 026-1 strain, 078-70 strains, 0111-2 strains, 0103-1 strain, 0141-1 strain. The number of untypable strains amounted to 32. Highest number of strains proved sensitive to colistin--96.06%, the remaining drugs following in a descending order: flumequine--95.65%, apramycin - 95.5%, gentamycin--93.72%, amoxicillin--93,8%, amikacin--88.57%, carbenicillin--86.88%, furazolidone--83,13%, and kanamycin--79.36%. High was the percent of strains resistant to tetracycline--66.17%, spectinomycin--61.67%, ampicillin--51.12%, chloramphenicol--50.23%, and streptomycin--44.84%.

  4. Increased amoxicillin-clavulanic acid resistance in Escherichia coli blood isolates, Spain.

    PubMed

    Oteo, Jesús; Campos, José; Lázaro, Edurne; Cuevas, Oscar; García-Cobos, Silvia; Pérez-Vázquez, María; de Abajo, F J

    2008-08-01

    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.

  5. Characterization of Escherichia coli O157 : H7 isolates causing haemolytic uraemic syndrome in France.

    PubMed

    Bidet, Philippe; Mariani-Kurkdjian, Patricia; Grimont, Francine; Brahimi, Naïma; Courroux, Céline; Grimont, Patrick; Bingen, Edouard

    2005-01-01

    Forty-seven non-epidemic Escherichia coli O157 : H7 isolates causing haemolytic uraemic syndrome in France were characterized. The isolates clustered into 36 clones using PFGE typing. All the isolates harboured eae and one or more copies of stx2 and belonged to phylogenetic group D. Nine per cent were resistant to amoxicillin.

  6. 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

  7. Identification of enterotoxigenic Escherichia coli isolates with enzyme-labeled synthetic oligonucleotide probes.

    PubMed Central

    Medon, P P; Lanser, J A; Monckton, P R; Li, P; Symons, R H

    1988-01-01

    Commercially available kits containing alkaline phosphatase-labeled oligonucleotide probes for Escherichia coli heat-stable enterotoxins (STI-H, STI-P, and STII) and the heat-labile enterotoxin were compared with bioassays and radiolabeled recombinant DNA probes to identify enterotoxigenic E. coli from 100 clinical isolates. There was very good agreement between the three methods. PMID:3053766

  8. [Development of chromogenic agar medium for isolation of enterohaemorrhagic Escherichia coli O26].

    PubMed

    Ikedo, M; Komatsu, O; Hara-Kudo, Y; Yamamoto, S; Kumagai, S

    2001-04-01

    Agar media for isolation of enterohaemorrhagic Escherichia coli (EHEC) have been developed primarily for E. coli O157, because this bacterium has most frequently caused EHEC infection. However, there have been few studies for isolation of other serotypes of EHEC, and media appropriate for isolation of such organisms, especially from food samples, are not yet available. Among such serotypes, E. coli O26 has often been isolated from clinical specimens from patients and animals, but not from food samples in outbreaks, because of lack of an appropriate method for isolation. In this study, we tried to develop a new chromogenic agar medium for selective isolation of E. coli O26 using the characteristics of E. coli O26. Fifteen strains of E. coli O26, 11 strains of E. coli O157 and 36 strains of other sero-types E. coli were tested for fermentation of rhamnose, cellobiose, dulcitol, salicin, raffinose, sorbitol, sucrose, lactose, mannitol, arabinose, maltose, xylose and glucose. Rhamnose was fermented by all E. coli strains except for E. coli O26. The other substrates were not effective for differentiating E. coli O26 from the other strains of E. coli. Thus the medium containing rhamnose and 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside, which is a substrate of beta-galactosidase specific to coliforms, produced a color of E. coli O26 colonies different from colors of the other bacteria. Furthermore, cefixime and sodium tellulite were added to the composition of the medium for gaining higher selectivity.

  9. SILVER NANOPARTICLES-DISK DIFFUSION TEST AGAINST Escherichia coli ISOLATES

    PubMed Central

    CUNHA, Francisco Afrânio; MAIA, Kamila Rocha; MALLMAN, Eduardo José Jucá; CUNHA, Maria da Conceição dos Santos Oliveira; MACIEL, Antonio Auberson Martins; de SOUZA, Ieda Pereira; MENEZES, Everardo Albuquerque; FECHINE, Pierre Basílio Almeida

    2016-01-01

    SUMMARY Nanotechnology can be a valuable ally in the treatment of infections. Silver nanoparticles (AgNPs) are structures that have antimicrobial activity. The aim of this study was to produce AgNPs by green methods, characterize these structures, and assess their antimicrobial activity against Escherichia coli associated with the antibiotic ciprofloxacin. AgNPs were characterized by spectroscopic and microscopic techniques. Antimicrobial activity was evaluated by the disk diffusion method against 10 strains of E. coli. The synthesized AgNPs showed a spherical shape and a size of 85.07 ± 12.86 nm (mean ± SD). AgNPs increased the activity of ciprofloxacin by 40% and may represent a new therapeutic option for the treatment of bacterial infections. PMID:27680178

  10. SILVER NANOPARTICLES-DISK DIFFUSION TEST AGAINST Escherichia coli ISOLATES.

    PubMed

    Cunha, Francisco Afrânio; Maia, Kamila Rocha; Mallman, Eduardo José Jucá; Cunha, Maria da Conceição Dos Santos Oliveira; Maciel, Antonio Auberson Martins; Souza, Ieda Pereira de; Menezes, Everardo Albuquerque; Fechine, Pierre Basílio Almeida

    2016-09-22

    Nanotechnology can be a valuable ally in the treatment of infections. Silver nanoparticles (AgNPs) are structures that have antimicrobial activity. The aim of this study was to produce AgNPs by green methods, characterize these structures, and assess their antimicrobial activity against Escherichia coli associated with the antibiotic ciprofloxacin. AgNPs were characterized by spectroscopic and microscopic techniques. Antimicrobial activity was evaluated by the disk diffusion method against 10 strains of E. coli. The synthesized AgNPs showed a spherical shape and a size of 85.07 ± 12.86 nm (mean ± SD). AgNPs increased the activity of ciprofloxacin by 40% and may represent a new therapeutic option for the treatment of bacterial infections.

  11. Characterization of a second lysine decarboxylase isolated from Escherichia coli.

    PubMed Central

    Kikuchi, Y; Kojima, H; Tanaka, T; Takatsuka, Y; Kamio, Y

    1997-01-01

    We report here on the existence of a new gene for lysine decarboxylase in Escherichia coli K-12. The hybridization experiments with a cadA probe at low stringency showed that the homologous region of cadA was located in lambda Kohara phage clone 6F5 at 4.7 min on the E. coli chromosome. We cloned the 5.0-kb HindIII fragment of this phage clone and sequenced the homologous region of cadA. This region contained a 2,139-nucleotide open reading frame encoding a 713-amino-acid protein with a calculated molecular weight of 80,589. Overexpression of the protein and determination of its N-terminal amino acid sequence defined the translational start site of this gene. The deduced amino acid sequence showed 69.4% identity to that of lysine decarboxylase encoded by cadA at 93.7 min on the E. coli chromosome. In addition, the level of lysine decarboxylase activity increased in strains carrying multiple copies of the gene. Therefore, the gene encoding this lysine decarboxylase was designated Idc. Analysis of the lysine decarboxylase activity of strains containing cadA, ldc, or cadA ldc mutations indicated that ldc was weakly expressed under various conditions but is a functional gene in E. coli. PMID:9226257

  12. Label-free identification of antibiotic resistant isolates of living Escherichia coli: Pilot study.

    PubMed

    Cheong, Youjin; Jin Kim, Young; Kang, Heeyoon; Choi, Samjin; Joo Lee, Hee

    2017-02-01

    We introduce a label-free spectroscopic method to classify subtypes of quinolone-nonsusceptible Escherichia coli (E. coli) isolates obtained from human blood cultures. Raman spectroscopy with a 30-nm gold-deposited, surface-enhanced Raman scattering (SERS) substrate was used to evaluate three multilocus sequencing typing (MLST)-predefined groups including E. coli ATCC25922, E. coli ST131:O75, and E. coli ST1193:O25b. Although there was a coffee-ring effect, the ring zone was selected at the ideal position to screen E. coli isolates. Strong Raman peaks were present at 1001-1004 cm(-1) (CC aromatic ring breathing stretching vibrational mode of phenylalanine), 1447-1448 cm(-1) (CH2 scissoring deformation vibrational mode), and 1667 cm(-1) (amide I α-helix). Although the three MLST-predefined E. coli isolates had similar Raman spectral patterns, a support vector machine (SVM) learning algorithm-assisted principal component analysis (PCA) analysis had superior performance in detecting the presence of quinolone-nonsusceptible E. coli isolates as well as classifying similar microbes, such as quinolone-nonsusceptible E. coli ST131:O75 and E. coli ST1193:O25b isolates. Therefore, this label-free and nondestructive technique is likely to be useful for clinically diagnosing quinolone-nonsusceptible E. coli isolates with the MLST method.

  13. Genome sequences of five multidrug resistant Escherichia coli ST117 isolates recovered from dairy calves

    USDA-ARS?s Scientific Manuscript database

    Escherichia coli ST117 have been recovered from poultry with colibacillosis, as well as urinary tract infections and fatal septic infections in humans. To further investigate ST117 isolates recovered from non-poultry food animals we sequenced the genomes of six ST117 isolates from dairy calves in Pe...

  14. 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.

  15. Virulence Factors and Clonal Relationships among Escherichia coli Strains Isolated from Broiler Chickens with Cellulitis

    PubMed Central

    de Brito, Benito Guimarães; Gaziri, Luiz Carlos J.; Vidotto, Marilda C.

    2003-01-01

    In this study, we compared Escherichia coli isolates from chickens with avian cellulitis with those from feces of healthy chickens. Cellulitis-derived strains presented phenotypic and genotypic characteristics of greater virulence than did the fecal isolates. Phylogenetic analysis by repetitive extragenic palindromic-PCR showed that, in agreement with their virulence characteristics, the cellulitis isolates form two clonal groups distinct from the fecal isolates. PMID:12819112

  16. Genetic Relatedness Among Escherichia coli Pathotypes Isolated from Food Products for Human Consumption in Cartagena, Colombia

    PubMed Central

    Amézquita-Montes, Zorangel; Tamborski, Maria; Kopsombut, Usa G.; Zhang, Chengxian; Arzuza, Octavio S.

    2015-01-01

    Abstract Foodborne pathogens are a leading cause of mild-to-severe gastrointestinal illnesses worldwide. Escherichia coli pathotypes have been known to cause gastrointestinal illnesses in children less than 5 years old in Colombia. However, insufficient information is available on the prevalence of E. coli contamination of food products and the kind of E. coli food product reservoirs. The two objectives of this study were designed to address this issue. The first objective was to ascertain coliform, E. coli, and pathogenic E. coli contamination of food products readily available for human consumption in Cartagena, Colombia. The second objective was to evaluate the relationship between pathogenic E. coli isolated from food products and those isolated from cases of diarrhea in children. Food product samples consisting of pasteurized milk, unpasteurized fruit juice, ground beef, cheese, and vegetables were obtained at four retail stores. The food samples were cultured in liquid media and tested for the presence of coliforms and E. coli. E. coli isolates were tested by polymerase chain reaction for the presence of pathogenic E. coli. Coliforms, E. coli, and E. coli intestinal pathotypes contamination were detected in 88.4%, 53%, and 2.1% of food product samples, respectively. Ground beef and cheese were the only food samples contaminated with E. coli intestinal pathotypes including enteropathogenic (EPEC), Shiga toxin–producing (STEC), and enterotoxigenic E. coli (ETEC). Closed multilocus sequencing typing relationships between diarrheagenic E. coli isolates from food products and from individuals with diarrhea suggest that food products readily available at public markets in Cartagena can transmit ETEC and possibly EPEC and STEC. We demonstrated that a high proportion of food products for human consumption available at public markets in Cartagena are contaminated with coliforms, E. coli, and E. coli intestinal pathogens. Furthermore, food products containing E. coli

  17. Genetic Relatedness Among Escherichia coli Pathotypes Isolated from Food Products for Human Consumption in Cartagena, Colombia.

    PubMed

    Amézquita-Montes, Zorangel; Tamborski, Maria; Kopsombut, Usa G; Zhang, Chengxian; Arzuza, Octavio S; Gómez-Duarte, Oscar G

    2015-05-01

    Foodborne pathogens are a leading cause of mild-to-severe gastrointestinal illnesses worldwide. Escherichia coli pathotypes have been known to cause gastrointestinal illnesses in children less than 5 years old in Colombia. However, insufficient information is available on the prevalence of E. coli contamination of food products and the kind of E. coli food product reservoirs. The two objectives of this study were designed to address this issue. The first objective was to ascertain coliform, E. coli, and pathogenic E. coli contamination of food products readily available for human consumption in Cartagena, Colombia. The second objective was to evaluate the relationship between pathogenic E. coli isolated from food products and those isolated from cases of diarrhea in children. Food product samples consisting of pasteurized milk, unpasteurized fruit juice, ground beef, cheese, and vegetables were obtained at four retail stores. The food samples were cultured in liquid media and tested for the presence of coliforms and E. coli. E. coli isolates were tested by polymerase chain reaction for the presence of pathogenic E. coli. Coliforms, E. coli, and E. coli intestinal pathotypes contamination were detected in 88.4%, 53%, and 2.1% of food product samples, respectively. Ground beef and cheese were the only food samples contaminated with E. coli intestinal pathotypes including enteropathogenic (EPEC), Shiga toxin-producing (STEC), and enterotoxigenic E. coli (ETEC). Closed multilocus sequencing typing relationships between diarrheagenic E. coli isolates from food products and from individuals with diarrhea suggest that food products readily available at public markets in Cartagena can transmit ETEC and possibly EPEC and STEC. We demonstrated that a high proportion of food products for human consumption available at public markets in Cartagena are contaminated with coliforms, E. coli, and E. coli intestinal pathogens. Furthermore, food products containing E. coli intestinal

  18. Genetic determinants of pathogenicity of Escherichia coli isolated from children with acute diarrhea in Maputo, Mozambique.

    PubMed

    Sumbana, Jose; Taviani, Elisa; Manjate, Alice; Paglietti, Bianca; Santona, Antonella; Colombo, Mauro M

    2015-07-04

    Diarrheagenic Escherichia coli (DEC) represents one of the leading cause of diarrhoea in developing countries. In this study a molecular approach was applied for the detection of diarrheagenic Escherichia coli (DEC) circulating in Maputo, Mozambique. All isolates were PCR tested for species-specific genes and for 11 molecular markers: stx1, stx2, eae, bfpA, lt, st, ipaH, aap, aggR CVD432 and daaE. Of the 80 E. coli isolated, 74% were potential DEC: 21% EIEC, 19% EPEC, 15% EAEC, 13% ETEC, 5% DAEC and 1% hybrids. This study revealed the complexity of the etiology of diarrhea caused by pathogenic E. coli in Mozambique, and the risk of the emergence of new pathogenic variants due to the horizontal transmission of pathogenicity factors.

  19. [Antibiotic resistance of Escherichia coli strains isolated from raw chicken meat in Senegal].

    PubMed

    Fofana, A; Bada Alambédji, R; Seydi, M; Akakpo, A J

    2006-01-01

    Antimicrobial-resistant Escherichia coli and others pathogens bacteria can be transferred from animals to humans through consumption of contaminated food and foods products and thus present a public health risk. The increase in E. coli resistance to commonly used antimicrobials both in the public health and veterinary sectors is one of the major threats of health care worldwide. The present study was undertaken to estimate the antimicrobial resistance of E. coli isolates from raw chicken meat in Dakar. Levying of skin and muscle have been carried out on 120 chicken carcasses bought from 13 sale points and 23 flocks beetween November 2003 and April 2004. 102 Escherichia coli strains have been isolated, among which, 90 were tested for their susceptibilities to 16 selected antibiotics by agar diffusion method. All Escherichia coli strains (100%), were resistant to one or more antibiotic; 60 strains (66.66%) being resistant to more than five antibiotics. Those frequently encountererd are: ampicillin, trimethoprim, trimethoprim-sulfametoxazole, tetracycline, sulfonamides, streptomycin, nalidixic acid. Multiple resistances to 12 antibiotics were also observed. The lowest resistances were noted with gentamicin (3.33%) and neomycin (5.56%). This study showed the significance of chicken meat as source of Escherichia coli strains with a simple or multiple resistance to various antibiotics tested. Further studies are necessary in order to determine bacterium mechanisms of resistance.

  20. [Antibioresistance of Escherichia coli strains isolated from raw chicken meat in Senegal].

    PubMed

    Fofana, A; Bada Alambedji, R; Seydi, M; Akakpo, A J

    2006-01-01

    Antimicrobial-resistant Escherichia coli and others pathogens bacteria can be transferred from animals to humans through consumption of contaminated food and foods products and thus present a public health risk. The increase in E. coli resistance to commonly used antimicrobials both in the public health and veterinary sectors is one of the major threats of health care worldwide. The present study was undertaken to estimate the antimicrobial resistance of E. coli isolates from raw chicken meat in Dakar. Levying of skin and muscle have been carried out on 120 chicken carcasses bought from 13 sale points and 23 flocks beetween November 2003 and April 2004. 102 Escherichia coli strains have been isolated, among which, 90 were tested for their susceptibilities to 16 selected antibiotics by agar diffusion method. All Escherichia coli strains (100%), were resistant to one or more antibiotic; 60 strains (66.66%) being resistant to more than five antibiotics. Those frequently encountererd are: ampicillin, trimethoprim, trimethoprim-sulfametoxazole, tetracycline, sulfonamides, streptomycin, nalidixic acid. Multiple resistances to 12 antibiotics were also observed. The lowest resistances were noted with gentamicin (3.33%) and neomycin (5.56%). This study showed the significance of chicken meat as source of Escherichia coli strains with a simple or multiple resistance to various antibiotics tested. Further studies are necessary in order to determine bacterium mechanisms of resistance.

  1. Draft Genome Sequences of Escherichia coli Isolates from Wounded Military Personnel.

    PubMed

    Arivett, Brock A; Ream, Dave C; Fiester, Steven E; Kidane, Destaalem; Actis, Luis A

    2016-08-11

    Members of the Escherichia coli bacterial family have been grouped as ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens because of their extensive drug resistance phenotypes and increasing threat to human health. The genomes of six extended-spectrum β-lactamase (ESBL)-producing E. coli strains isolated from wounded military personnel were sequenced and annotated.

  2. 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.

  3. Isolation and characterization of Escherichia coli recovered from Maryland apple cider and the cider production environment.

    PubMed

    Senkel, I Arthur; Jolbitado, Beverly; Zhang, Yifan; White, David G; Ayers, Sherry; Meng, Jianghong

    2003-12-01

    Contaminated apple cider has been implicated in several Escherichia coli O157:H7 outbreaks. In an attempt to investigate sources and modes of entry of E. coli into apple cider, samples of fresh apple, pomace, and cider and equipment and mill floor swabs were analyzed for standard plate counts (SPC), total coliforms (TC), fecal coliforms (FC), and E. coli. E. coli was isolated from 14 (33%) of 42 samples of bottled fresh cider, from food equipment in 6 (67%) of 9 mills, and from apples, pomace, or cider in 7 (78%) of 9 mills. Seventy-five E. coli isolates were further characterized for Shiga toxin-producing E. coli (STEC)-associated virulence factors, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) type. No E. coli O157:H7 or other STEC was identified. Serotyping and PFGE revealed 64 distinct profiles, suggesting that recovered E. coli arose from multiple independent sources. However, on one occasion, E. coli isolated from the source apple sample was closely related to the E. coli identified in the finished cider sample. E. coli isolates were further tested for antimicrobial susceptibility to 17 antimicrobial agents of human and veterinary importance. Fourteen (19%) of the 75 isolates were resistant to at least one of the antimicrobial agents tested, and 9 (12%) were resistant to at least two of these agents. Of the resistant isolates recovered, 64% were resistant to tetracycline and 57% were resistant to streptomycin. Overall, the level of E. coli contamination in source apple samples did not differ significantly from those in samples of pomace, cider at the press, and cider entering the bottling tank; therefore, source apples cannot be dismissed as a potential contributor of E. coli to the cider-making process.

  4. Antimicrobial resistance in Escherichia coli strains isolated from Swiss weaned pigs and sows.

    PubMed

    Stannarius, C; Bürgi, E; Regula, G; Zychowska, M A; Zweifel, C; Stephan, R

    2009-03-01

    Based on Directive (EC) No 99/2003, monitoring programs on the development of antimicrobial resistance in bacteria from livestock are implemented in many European countries. The aim of the present study was (i) to establish comprehensive baseline data on the antimicrobial resistance situation in Escherichia coli isolates obtained from healthy pigs (pooled fecal samples) originating from 60 Swiss pig-breeding farms, and (ii) to analyze differences in the resistance frequency between Escherichia coli isolates from weaned pigs and sows. Susceptibility testing (disc diffusion method) was performed on 429 isolates from weaned pigs and 431 isolates from sows. Overall, 17.7% of the isolates from weaned pigs and 22.5% of the Escherichia coli isolates from sows were susceptible to all antibiotics tested. Low resistance prevalence was found for amoxicillin, amoxicillin/clavulanic acid, ampicillin, cefquinome, ciprofloxacin, colistin, florfenicol, and gentamicin. The most frequently found resistances were against streptomycin (60.6% of the isolates from weaners and 64.3% of the isolates from sows), sulfonamide (51.5% and 26.9%), tetracycline (35.2% and 22.0%), and trimethoprim (27.5% and 11.1%). With exception of colistin, most resistances were found for those antibiotics commonly used on the farms. Except for ciprofloxacin and streptomycin, isolates from weaned pigs showed higher resistance prevalence than those from sows. This difference was significant for cefquinome, florfenicol, sulfonamide, tetracycline, and trimethoprim (p<0.05).

  5. [Isolation of avian Escherichia coli and PCR detection of their F1 and HPI genes].

    PubMed

    Zhu, Shan-Yuan; Lu, Hui; Wang, Jian

    2007-10-01

    To further investigate into the prevalence of F1 fimbriae and high pathogenicity island (HPI) in avian Escherichia coli, a total of 69 bacteria isolates (29 from geese and 40 from chickens) were obtained from deceased poultry and characterized to be Escherichia coli by gram staining, culture characterizing and bio-chemical testing. Two sets of primers were designed or analyzed with DNAStar software based on the F1 and HPI sequences that deposited in GenBank and synthesized by Sangon Biological Engineering Technology and Service Co. Ltd. (Shanghai, P. R. China). All the primers were tested for their specificities by using reference E. coli strains, and it is confirmed that the PCR using primers F1-F and F1-R could identify F1+ E. coli, as well as the PCR using primers irp-F and irp-R could identify HPI+ E. coli. All the isolates were submitted to PCR detection, and the data shows 46 isolates (66.7%) were F1-positive, 10 isolates (14.5%) were F1+ HPI-positive and 2 isolates (20.0%) were HPI-positive. Furthermore analysis indicated that the prevalence of F1 and HPI have no different between the isolates from geese and chickens, and no different among the isolates from different tissue, such as liver, lung and duodenum. In addition, all the 69 E. coli isolates serological typed, and the results show that the isolates from geese were belonged to O26 (25.0%), O78 (12.5%), O18 (12.5%) and O117 (12.5%), while E coli from chickens were fell into O109 (37.5%), O24 (18.75%), O18 (12.5%), O139 (12.5%) and O78 (6.25%). Seven kinds of antibiotics were tested on 11 isolates, and it revealed that most isolates were sensitive to cefazolin, nitrofurantoin and gentamycin, while resistant to lincomycin, tetracycline and polymycin B.

  6. Complete Genome Sequence of Escherichia coli Strain M8, Isolated from ob/ob Mice

    PubMed Central

    Siddharth, Jay; Membrez, Mathieu; Chakrabarti, Anirikh; Betrisey, Bertrand; Chou, Chieh Jason

    2017-01-01

    ABSTRACT Escherichia coli is one of the common inhabitants of the mammalian gastrointestinal track. We isolated a strain from an ob/ob mouse and performed whole-genome sequencing, which yielded a chromosome of ~5.1 Mb and three plasmids of ~160 kb, ~6 kb, and ~4 kb. PMID:28572322

  7. Shiga toxin-producing serogroup O91 Escherichia coli strains isolated from food and environmental samples

    USDA-ARS?s Scientific Manuscript database

    Shiga toxin-producing Escherichia coli (STEC) strains of the O91: H21 serotype have caused severe infections, including hemolytic-uremic syndrome. Strains of the O91 serogroup have been isolated from food, animals, and the environment worldwide but are not well characterized. We used a microarray an...

  8. Development of an automated multiplexed immunomagnetic separation system for isolating Shiga toxin-producing Escherichia coli

    USDA-ARS?s Scientific Manuscript database

    In recent years, non-O157 Shiga toxin-producing Escherichia coli(STEC) have become an emerging problem. Efforts have been devoted to facilitating and speeding their detection, however, their isolation from high background microbiota foods remains problematic. To solve this problem, immunomagnetic se...

  9. Detection of Florfenicol Resistance Genes in Escherichia coli Isolated from Sick Chickens

    PubMed Central

    Keyes, Kathleen; Hudson, Charlene; Maurer, John J.; Thayer, Stephan; White, David G.; Lee, Margie D.

    2000-01-01

    Florfenicol is an antibiotic approved for veterinary use in cattle in the United States in 1996. Although this drug is not used in poultry, we have detected resistance to florfenicol in clinical isolates of avian Escherichia coli. Molecular typing demonstrated that the florfenicol resistance gene, flo, was independently acquired and is plasmid encoded. PMID:10639375

  10. Emergence of Carbapenemase-Producing Escherichia coli Isolated from Companion Animals in Algeria.

    PubMed

    Yousfi, Massilia; Touati, Abdelaziz; Mairi, Assia; Brasme, Lucien; Gharout-Sait, Alima; Guillard, Thomas; De Champs, Christophe

    2016-06-01

    The emergence and worldwide spread of carbapenemase-producing Enterobacteriaceae is of great concern to public health. The aim of this study was to investigate the occurrence of carbapenemase-producing Escherichia coli in companion animals in Algeria. Two hundred fecal samples were obtained from healthy and diseased dogs and cats in one veterinary office and private owners in Bejaia city, Algeria, during November 2014 to March 2015. Isolates were screened by polymerase chain reaction for the presence of carbapenemase, acquired plasmidic AmpC (pAmpC) and extended-spectrum beta-lactamase genes. Five carbapenemase-producing E. coli isolates were detected including four OXA-48-producing isolates and one isolate producing NDM-5. Coexpression of ESBL and pAmpC genes was observed in these isolates. Phylogenetic grouping revealed that these isolates belonged to A and D phylogroups. The results of this study show that carbapenemase-producing E. coli spread to the companion animals in Algeria.

  11. 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 O60 or O101 (35%). Phylogroup B1, serogroups O60 and O101 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.

  12. Occurrence of Virulence Genes Associated with Diarrheagenic Pathotypes in Escherichia coli Isolates from Surface Water

    PubMed Central

    Ahmed, Warish; Hodgers, Leonie; Toze, Simon

    2013-01-01

    Escherichia coli isolates (n = 300) collected from six sites in subtropical Brisbane, Australia, prior to and after storm events were tested for the presence of 11 virulence genes (VGs) specific to diarrheagenic pathotypes. The presence of eaeA, stx1, stx2, and ehxA genes specific for the enterohemorrhagic E. coli (EHEC) pathotype was detected in 56%, 6%, 10%, and 13% of isolates, respectively. The VGs astA (69%) and aggR (29%), carried by enteroaggregative (EAEC) pathotypes, were frequently detected in E. coli isolates. The enteropathogenic E. coli (EPEC) gene bfp was detected in 24% of isolates. In addition, enteroinvasive E. coli (EIEC) VG ipaH was also detected in 14% of isolates. During dry periods, isolates belonging to the EAEC pathotype were most commonly detected (23%), followed by EHEC (11%) and EPEC (11%). Conversely, a more uniform prevalence of pathotypes, EPEC (14%), EAEC (12%), EIEC (10%), EHEC (7%), and ETEC (7%), was observed after the storm events. The results of this study highlight the widespread occurrence of potentially diarrheagenic pathotypes in the urban aquatic ecosystems. While the presence of VGs in E. coli isolates alone is insufficient to determine pathogenicity, the presence of diarrheagenic E. coli pathotypes in high frequency after the storm events could lead to increased health risks if untreated storm water were to be used for nonpotable purposes and recreational activities. PMID:23124225

  13. Antimicrobial resistance of Escherichia coli isolates from canine urinary tract infections

    PubMed Central

    CHANG, Shao-Kuang; LO, Dan-Yuan; WEI, Hen-Wei; KUO, Hung-Chih

    2014-01-01

    This study determined the antimicrobial resistance profiles of Escherichia coli isolates from dogs with a presumptive diagnosis of urinary tract infection (UTI). Urine samples from 201 dogs with UTI diagnosed through clinical examination and urinalysis were processed for isolation of Escherichia coli. Colonies from pure cultures were identified by biochemical reactions (n=114) and were tested for susceptibility to 18 antimicrobials. The two most frequent antimicrobials showing resistance in Urinary E. coli isolates were oxytetracycline and ampicillin. Among the resistant isolates, 17 resistance patterns were observed, with 12 patterns involving multidrug resistance (MDR). Of the 69 tetracycline-resistant E. coli isolates, tet(B) was the predominant resistance determinant and was detected in 50.9% of the isolates, whereas the remaining 25.5% isolates carried the tet(A) determinant. Most ampicillin and/or amoxicillin-resistant E. coli isolates carried blaTEM-1 genes. Class 1 integrons were prevalent (28.9%) and contained previously described gene cassettes that are implicated primarily in resistance to aminoglycosides and trimethoprim (dfrA1, dfrA17-aadA5). Of the 44 quinolone-resistant E. coli isolates, 38 were resistant to nalidixic acid, and 6 were resistant to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in the GyrA (Ser83Leu) and ParC (Ser80Ile) genes. Furthermore, the aminoglycoside resistance gene aacC2, the chloramphenicol resistant gene cmlA and the florfenicol resistant gene floR were also identified. This study revealed an alarming rate of antimicrobial resistance among E. coli isolates from dogs with UTIs. PMID:25720807

  14. Isolation of extraintestinal pathogenic Escherichia coli from diarrheic dogs and their antimicrobial resistance profile

    PubMed Central

    de Cleber Jacob Silva Paula; Marin, José Moacir

    2008-01-01

    From January to December 2006, 92 Escherichia coli isolates from 25 diarrheic dogs were analyzed by screening for the presence of adhesin-encoding genes (pap, sfa, afa), hemolysin and aerobactin genes. Virulence gene frequencies detected in those isolates were: 12% pap, 1% sfa, 10% hemolysin and 6.5% aerobactin. Ten isolates were characterized as extraintestinal pathogenic E. coli (ExPEC) strains; all showed a multidrug resistance phenotype that may represent a reason for concern due the risk of dissemination of antimicrobial resistant genes to the microbiota of human beings. PMID:24031253

  15. Genome-wide transcriptome analysis of fluoroquinolone resistance in clinical isolates of Escherichia coli.

    PubMed

    Yamane, Takashi; Enokida, Hideki; Hayami, Hiroshi; Kawahara, Motoshi; Nakagawa, Masayuki

    2012-04-01

    Coincident with their worldwide use, resistance to fluoroquinolones in Escherichia coli has increased. To identify the gene expression profiles underlying fluoroquinolone resistance, we carried out genome-wide transcriptome analysis of fluoroquinolone-sensitive E. coli. Four fluoroquinolone-sensitive E. coli and five fluoroquinolone-resistant E. coli clinical isolates were subjected to complementary deoxyribonucleic acid microarray analysis. Some upregulated genes' expression was verified by real-time polymerase chain reaction using 104 E. coli clinical isolates, and minimum inhibitory concentration tests were carried out by using their transformants. A total of 40 genes were significantly upregulated in fluoroquinolone-resistant E. coli isolates (P < 0.05). The expression of phage shock protein operons, which are involved in biofilm formation, was markedly upregulated in our profile of fluoroquinolone-resistant E. coli. One of the phage shock protein operons, pspC, was significantly upregulated in 50 fluoroquinolone-resistant E. coli isolates (P < 0.0001). The expression of type I fimbriae genes, which are pilus operons involved in biofilm formation, were markedly downregulated in fluoroquinolone-resistant E. coli. Deoxyribonucleic acid adenine methyltransferase (dam), which represses type I fimbriae genes, was significantly upregulated in the clinical fluoroquinolone-resistant E. coli isolates (P = 0.007). We established pspC- and dam-expressing E. coli transformants from fluoroquinolone-sensitive E. coli, and the minimum inhibitory concentration tests showed that the transformants acquired fluoroquinolone resistance, suggesting that upregulation of these genes contributes to acquiring fluoroquinolone resistance. Upregulation of psp operones and dam underlying pilus operons downregulation might be associated with fluoroquinolone resistance in E. coli. © 2011 The Japanese Urological Association.

  16. Transport of Escherichia coli strains isolated from natural spring water.

    PubMed

    Lutterodt, G; Foppen, J W A; Uhlenbrook, S

    2012-10-01

    We present a new methodology to scale up bacteria transport experiments carried out in the laboratory to practical field situations. The key component of the methodology is to characterize bacteria transport not by a constant sticking efficiency, but by a range of sticking efficiency values determined from laboratory column experiments. In this study, initially, we harvested six Escherichia coli strains from springs in Kampala, the capital of Uganda, and then we carried out a number of experiments with 1.5m high columns of quartz sand with various sampling ports in order to determine the fraction of bacteria as a function of sticking efficiency. Furthermore, we developed a simple mathematical formulation, based on the steady-state analytical solution for the transport of mass in the subsurface, to arrive at bacteria concentrations as a function of transport distance. The results of the quartz sand column experiments indicated that the fractional bacteria mass and sticking efficiency of most of the strains we harvested could be adequately described by a power law. When applying the power distributions to the field situation in Kampala, we found that the transport distance required to reduce bacteria concentrations with five log units ranged from 1.5 to 23m, and this was up to three times more than when using a constant sticking efficiency. The methodology we describe is simple, can be carried out in a spreadsheet, and in addition to parameters describing transport, like pore water flow velocity and dispersion, only two constants are required, which define the relation between sticking efficiency and percentage of bacteria mass.

  17. Genotype Analysis of Escherichia coli Strains Isolated from Children and Chickens Living in Close Contact

    PubMed Central

    Kariuki, S.; Gilks, C.; Kimari, J.; Obanda, A.; Muyodi, J.; Waiyaki, P.; Hart, C. A.

    1999-01-01

    Escherichia coli isolates from rectal swabs from 62 chickens and stools from 42 children living in close contact with chickens on the same farms in Kiambu district, Kenya, were compared for their genetic relatedness. Antibiotic susceptibility profiles broadly categorized isolates from the children and from the chickens into two separate clusters: the majority (144; 85.5%) of the E. coli isolates from children were multidrug resistant, while the majority (216; 87.1%) of the E. coli isolates from chickens were either fully susceptible or resistant only to tetracycline. Sixty- and 100- to 110-MDA plasmids were found to encode the transferable resistance to co-trimoxazole and tetracycline. HindIII restriction endonuclease digestion of the 60- and 100- to 110-MDA plasmids produced four distinct patterns for isolates from children and three distinct patterns for isolates from chickens. XbaI digestion of genomic DNA followed by pulsed-field gel electrophoresis (PFGE) analysis produced 14 distinct clusters. There were six distinct PFGE clusters among the isolates from children, while among the isolates from chickens there were seven distinct clusters. Only one PFGE cluster contained isolates from both children and chickens, with the isolates displaying an approximately 60% coefficient of similarity. This study showed that although several different genotypes of E. coli were isolated from children and chickens from the same farms, the E. coli strains from these two sources were distinct. PMID:9925570

  18. 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.

  19. 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.

  20. 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

  1. Antimicrobial drug resistance in Escherichia coli isolated from commercial chicken eggs in Grenada, West Indies.

    PubMed

    Arathy, D S; Vanpee, G; Belot, G; Mathew, V; DeAllie, C; Sharma, R

    2011-01-01

    To determine the antimicrobial resistance profile of Escherichia coli (E coli) isolated from the shell membrane and yolk of commercial chicken eggs in Grenada. A total of 450 eggs were collected from different locations including small (33.3%) and big farms (26.7%), roadside vendors (26.7%) and supermarkets (13.3%). The shell membranes and yolk were cultured separately on blood agar and McConkey Agar Escherichia coli were identified using biochemical tests and API20E strips. The isolates were tested for antimicrobial sensitivity. A total of 55 E coli isolates were obtained. Of which 34 isolates were from shell membrane and 21 from yolk samples. Twenty-two of the total 34 isolates from shell membrane exhibited resistance to one or more of the antibiotics used in the study whereas 11 of the 21 yolks isolate also showed resistance to one or more of the tested antibiotics. Among the six antibiotics tested, the highest level of resistance was observed for ampicillin, 42.9 per cent and 31.8 per cent respectively for shell membrane and yolk isolates. The lowest resistance rate among all the antibiotics was observed against enrofloxacin (0%). Multi-drug resistance (resistance to > or = 3 compounds) was observed in 10.9% of the isolates. This study on E coli drug resistance in commercial chicken eggs in Grenada generated baseline data indicating that chicken eggs used for food can harbour resistant E coli. A regular monitoring of commensal and clinical isolates of E coli for antibacterial resistance is warranted.

  2. Relationship of biofilm formation and different virulence genes in uropathogenic Escherichia coli isolates from Northwest Iran

    PubMed Central

    Fattahi, Sargol; Kafil, Hossein Samadi; Nahai, Mohammad Reza; Asgharzadeh, Mohammad; Nori, Roghaya; Aghazadeh, Mohammad

    2015-01-01

    Background and objectives: The Escherichia coli (E. coli) bacterium is one of the main causative agents of urinary tract infections (UTI) worldwide. The ability of this bacterium to form biofilms on medical devices such as catheters plays an important role in the development of UTI. The aim of the present study was to investigate the possible relationship between virulence factors and biofilm formation of E. coli isolates responsible for urinary tract infection. Materials and methods: A total of 100 E. coli isolates isolated from patients with UTI were collected and characterized by routine bacteriological methods. In vitro biofilm formation by these isolates was determined using the 96-well microtiter-plate test, and the presence of fimA, papC, and hly virulence genes was examined by PCR assay. Data analysis was performed using SPSS 16.0 software. Results: From 100 E. coli isolates isolated from UTIs, 92% were shown to be biofilm positive. The genes papC, fimA, and hly were detected in 43%, 94% and 26% of isolates, respectively. Biofilm formation in isolates that expressed papC, fimA, and hly genes was 100%, 93%, and 100%, respectively. A significant relationship was found between presence of the papC gene and biofilm formation in E. coli isolates isolated from UTI (P<0.01), but there was no statistically significant correlation between presence of fimA and hly genes with biofilm formation (P<0.072, P<0.104). Conclusion: Results showed that fimA and hly genes do not seem to be necessary or sufficient for the production of biofilm in E. coli, but the presence of papC correlates with increased biofilm formation of urinary tract isolates. Overall, the presence of fimA, papC, and hly virulence genes coincides with in vitro biofilm formation in uropathogenic E. coli isolates. PMID:26213679

  3. 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.

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

    PubMed Central

    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

  5. A longitudinal study of Escherichia coli strains isolated from captive mammals, birds, and reptiles in Trinidad.

    PubMed

    Gopee, N V; Adesiyun, A A; Caesar, K

    2000-09-01

    A longitudinal study was conducted of the prevalence and characteristics of Escherichia coli in mammals, birds, and reptiles housed at the Emperor Valley Zoo, Trinidad. During a 6-mo study period, swabs were obtained from fecal samples that were randomly collected from the enclosures of animals from these three taxonomic groups every 3 wk. With snakes, both cloacal and fecal swabs were obtained. Fecal and cloacal swabs were cultured for E. coli on eosin methylene blue agar. The production of mucoid colonies and hemolytic colonies and non-sorbitol fermenter status were identified. The occurrence of O157 strains was determined amongst E. coli isolates that were non-sorbitol fermenters, and the disc diffusion method was used to determine the antibiograms of isolates. The frequency of E. coli isolation was significantly higher in mammals compared with birds and reptiles. Overall, the frequencies of isolation of E. coli from omnivores. herbivores, and carnivores, 87.2%, 70.0%, and 57.3%, respectively, regardless of animal class, were significantly different. Most (99.6%) of the E. coli isolates tested for antibiotic sensitivity exhibited resistance to one or more of the eight antimicrobial agents used. The possession of phenotypic virulence markers by the E. coli isolates studied and the generally high resistance to antimicrobial agents may have health implications for the zoological collection.

  6. 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.

  7. 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

  8. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh.

    PubMed

    Rahman, Shahedur; Parvez, Anowar Khasru; Islam, Rezuanul; Khan, Mahboob Hossain

    2011-03-15

    Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm). Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.

  9. [Evaluation of beta-glucuronidase activity for the isolation of diarrhea-causing Escherichia coli].

    PubMed

    Muto, T; Arai, K; Miyai, M

    1991-06-01

    To compare the isolating efficiency of diarrhea-causing Escherichia coli between Fluorocult agar plates, which reveal the beta-glucuronidase activity of E. coli, and a combination of SS and DHL agar plates, a total of 330 fecal specimens collected from outpatients were examined. Diarrhea-causing E. coli, identified by serological and toxigenic characters, were demonstrated in 52 samples. Among these specimens, 35 samples tested were positive on the Fluorocult agar plates, and 26 samples on the combination of SS and DHL agar plates. However, only 10 samples were positive on both the Fluorocult agar plates and the combination of SS and DHL agar plates. Thus, using Fluorocult agar plates for the isolation of diarrhea-causing E. coli in addition to the conventional SS and DHL agar plates will improve isolating efficacy.

  10. Biofilm-Forming Abilities of Shiga Toxin-Producing Escherichia coli Isolates Associated with Human Infections

    PubMed Central

    Vogeleer, Philippe; Tremblay, Yannick D. N.; Jubelin, Grégory; Jacques, Mario

    2015-01-01

    Forming biofilms may be a survival strategy of Shiga toxin-producing Escherichia coli to enable it to persist in the environment and the food industry. Here, we evaluate and characterize the biofilm-forming ability of 39 isolates of Shiga toxin-producing Escherichia coli isolates recovered from human infection and belonging to seropathotypes A, B, or C. The presence and/or production of biofilm factors such as curli, cellulose, autotransporter, and fimbriae were investigated. The polymeric matrix of these biofilms was analyzed by confocal microscopy and by enzymatic digestion. Cell viability and matrix integrity were examined after sanitizer treatments. Isolates of the seropathotype A (O157:H7 and O157:NM), which have the highest relative incidence of human infection, had a greater ability to form biofilms than isolates of seropathotype B or C. Seropathotype A isolates were unique in their ability to produce cellulose and poly-N-acetylglucosamine. The integrity of the biofilms was dependent on proteins. Two autotransporter genes, ehaB and espP, and two fimbrial genes, z1538 and lpf2, were identified as potential genetic determinants for biofilm formation. Interestingly, the ability of several isolates from seropathotype A to form biofilms was associated with their ability to agglutinate yeast in a mannose-independent manner. We consider this an unidentified biofilm-associated factor produced by those isolates. Treatment with sanitizers reduced the viability of Shiga toxin-producing Escherichia coli but did not completely remove the biofilm matrix. Overall, our data indicate that biofilm formation could contribute to the persistence of Shiga toxin-producing Escherichia coli and specifically seropathotype A isolates in the environment. PMID:26712549

  11. Biofilm-Forming Abilities of Shiga Toxin-Producing Escherichia coli Isolates Associated with Human Infections.

    PubMed

    Vogeleer, Philippe; Tremblay, Yannick D N; Jubelin, Grégory; Jacques, Mario; Harel, Josée

    2015-12-28

    Forming biofilms may be a survival strategy of Shiga toxin-producing Escherichia coli to enable it to persist in the environment and the food industry. Here, we evaluate and characterize the biofilm-forming ability of 39 isolates of Shiga toxin-producing Escherichia coli isolates recovered from human infection and belonging to seropathotypes A, B, or C. The presence and/or production of biofilm factors such as curli, cellulose, autotransporter, and fimbriae were investigated. The polymeric matrix of these biofilms was analyzed by confocal microscopy and by enzymatic digestion. Cell viability and matrix integrity were examined after sanitizer treatments. Isolates of the seropathotype A (O157:H7 and O157:NM), which have the highest relative incidence of human infection, had a greater ability to form biofilms than isolates of seropathotype B or C. Seropathotype A isolates were unique in their ability to produce cellulose and poly-N-acetylglucosamine. The integrity of the biofilms was dependent on proteins. Two autotransporter genes, ehaB and espP, and two fimbrial genes, z1538 and lpf2, were identified as potential genetic determinants for biofilm formation. Interestingly, the ability of several isolates from seropathotype A to form biofilms was associated with their ability to agglutinate yeast in a mannose-independent manner. We consider this an unidentified biofilm-associated factor produced by those isolates. Treatment with sanitizers reduced the viability of Shiga toxin-producing Escherichia coli but did not completely remove the biofilm matrix. Overall, our data indicate that biofilm formation could contribute to the persistence of Shiga toxin-producing Escherichia coli and specifically seropathotype A isolates in the environment.

  12. 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.

  13. Genetic relatedness of Escherichia coli isolates in interstitial water from a Lake Huron (Canada) beach.

    PubMed

    Kon, Tatiana; Weir, Susan C; Howell, E Todd; Lee, Hung; Trevors, Jack T

    2007-03-01

    Research was undertaken to characterize Escherichia coli isolates in interstitial water samples of a sandy beach on the southeastern shore of Lake Huron, Ontario, Canada. A survey of the beach area revealed the highest abundance of E. coli in interstitial water of the foreshore beach sand next to the swash zone. Higher concentrations of E. coli (up to 1.6 x 10(6) CFU/100 ml of water) were observed in the interstitial water from the sampling holes on the beach itself compared to lake water and sediment. Repetitive extragenic palindromic PCR (REP-PCR) was used to characterize the genetic diversity of E. coli isolates from interstitial water samples on the beach. E. coli isolates from the same sampling location frequently exhibited the same REP-PCR pattern or were highly similar to each other. In contrast, E. coli isolates from different sampling locations represented populations distinct from each other. This study has identified a unique ecological niche within the foreshore area of the beach where E. coli may survive and possibly multiply outside of host organisms. The results are of interest as increasing concentrations of E. coli in recreational waters are often considered to be an indication of recent fecal pollution.

  14. Capsule reduces adherence of enterotoxigenic Escherichia coli to isolated intestinal epithelial cells of pigs.

    PubMed Central

    Runnels, P L; Moon, H W

    1984-01-01

    Previous reports have demonstrated that heat-stable (A-type) capsule on piliated enterotoxigenic Escherichia coli enhances colonization of enterotoxigenic E. coli in the small intestine and enhances virulence of enterotoxigenic E. coli. In this report, four encapsulated enterotoxigenic E. coli strains and one encapsulated nonenterotoxigenic strain of E. coli and their nonencapsulated mutants were tested for adhesion to isolated intestinal epithelial cells or brush borders from neonatal pigs. The enterotoxigenic E. coli also expressed the K99 pilus antigen. The nonencapsulated mutants of the four enterotoxigenic E. coli adhered in higher numbers than did the encapsulated parental strains. Both the encapsulated and nonencapsulated forms of enterotoxigenic E. coli 431 grown at 18 degrees C (K99 production suppressed) adhered poorly to the isolated cells. The nonenterotoxigenic E. coli 1793 which does not express K99 antigen also adhered poorly in both encapsulated and nonencapsulated forms. Fab fragments of anticapsular immunoglobulin G failed to block the effect of capsule on adherence of strain 431. The results indicated that K99 was the principal mediator of in vitro adhesion of the enterotoxigenic E. coli strains and that capsule impedes the in vitro adhesion. They also suggested that the capsular enhancement of colonization by such strains in vivo probably is by some mechanism other than enhanced adhesion to epithelium. PMID:6147310

  15. Capsule reduces adherence of enterotoxigenic Escherichia coli to isolated intestinal epithelial cells of pigs.

    PubMed

    Runnels, P L; Moon, H W

    1984-09-01

    Previous reports have demonstrated that heat-stable (A-type) capsule on piliated enterotoxigenic Escherichia coli enhances colonization of enterotoxigenic E. coli in the small intestine and enhances virulence of enterotoxigenic E. coli. In this report, four encapsulated enterotoxigenic E. coli strains and one encapsulated nonenterotoxigenic strain of E. coli and their nonencapsulated mutants were tested for adhesion to isolated intestinal epithelial cells or brush borders from neonatal pigs. The enterotoxigenic E. coli also expressed the K99 pilus antigen. The nonencapsulated mutants of the four enterotoxigenic E. coli adhered in higher numbers than did the encapsulated parental strains. Both the encapsulated and nonencapsulated forms of enterotoxigenic E. coli 431 grown at 18 degrees C (K99 production suppressed) adhered poorly to the isolated cells. The nonenterotoxigenic E. coli 1793 which does not express K99 antigen also adhered poorly in both encapsulated and nonencapsulated forms. Fab fragments of anticapsular immunoglobulin G failed to block the effect of capsule on adherence of strain 431. The results indicated that K99 was the principal mediator of in vitro adhesion of the enterotoxigenic E. coli strains and that capsule impedes the in vitro adhesion. They also suggested that the capsular enhancement of colonization by such strains in vivo probably is by some mechanism other than enhanced adhesion to epithelium.

  16. 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.

  17. Isolation and molecular characterization of Escherichia coli O157 from broiler and human samples.

    PubMed

    Kalin, Recep; Ongor, Hasan; Cetinkaya, Burhan

    2012-04-01

    There is a lack of information about the role of poultry, specifically chicken, in transmission of Escherichia coli (E. coli) O157 and subsequent human illnesses. This study was therefore aimed at investigating the presence of E. coli O157 and its virulence genes in various samples collected from broiler chickens and humans in Eastern Turkey by culture, immunomagnetic separation (IMS), and polymerase chain reaction (PCR). The genetic relationship between broiler and human isolates was also examined by pulsed-field gel electrophoresis (PFGE). In the PCR analysis of sorbitol-negative isolates, E. coli O157 was identified in 0.1% (1/1000) and 0.4% (4/1000) of the liver and cecum samples of broiler chickens, respectively. On the other hand, none of the carcass samples were determined to be positive for E. coli O157. Overall, the results indicated that 12% (3/25) of the flocks were positive for E. coli O157. The differences between the flocks in terms of the positivity were determined to be statistically significant (p<0.001). Ten (2.7%) of 367 human stool samples were also positive for E. coli O157 in the PCR examination. None of the broiler and human E. coli O157 isolates possessed H7, shigatoxins 1-2, or enterohemolysin genes, whereas all the broiler isolates and one of the human isolates were positive for intimin gene. In the PFGE analysis, a total of eight different profiles (four from broiler and four from human isolates) were observed. However, there were no genetic relationships between broiler and human E. coli O157 isolates. It can be concluded that more detailed studies are needed in poultry to better understand the role of these species in the epidemiology of E. coli 0157 infections in humans.

  18. Antibiotic resistance in Escherichia coli isolated from retail raw chicken meat in Taif, Saudi Arabia.

    PubMed

    Altalhi, Abdullah D; Gherbawy, Youssuf A; Hassan, Sabry A

    2010-03-01

    The present study was carried out to screen and analyze the genetic characteristics of antibiotic resistance in Escherichia coli strains isolated from chicken meat marketed in the local markets of the Taif region in Saudi Arabia. A total of 119 samples were purchased from various supermarkets and examined for bacterial contamination with resistant E. coli. Thirty-seven E. coli isolates were evaluated for their antibiotic susceptibilities and the presence of class 1 integrons and antibiotic resistance genes. Results of antibiograms revealed that E. coli isolates were resistant to one or more of the antibiotics tested. Resistance was most frequently observed against sulphafurazole (89.2%), ampicillin (78.4%), nalidixic acid (70.3%), streptomycin (48.6%), chloramphenicol (32.4%), and gentamicin (24.3%). Fifteen E. coli strains have multidrug resistance phenotypes and harbored at least three antibiotic resistance genes. The bla(TEM) (beta-lactamase) and sul (sulfonamide) resistance encoding genes were detected in all the tested isolates. Polymerase chain reaction screening detected class 1 integrons in all multiresistant E. coli isolates. The present study provides an assessment of the occurrence of multidrug resistance of E. coli from raw chicken meat collected from local markets.

  19. Characterization of Carbapenem-Resistant Escherichia coli Isolates Through the Whole-Genome Sequencing Analysis.

    PubMed

    Luo, Yanping; Luo, Rong; Ding, Hong; Ren, Xiu; Luo, Haipeng; Zhang, Ying; Ye, Liyan; Cui, Shenghui

    2017-07-07

    Limited studies have characterized multiple carbapenem-resistant Escherichia coli isolates and compared their genetic characteristics through whole-genome sequencing (WGS) because of the scarcity of these isolates. In this study, we determined the prevalence of carbapenem resistance in 2,993 E. coli isolates collected from three Chinese hospitals. The carbapenem-resistant isolates were further characterized by WGS, and the molecular epidemiological characters and resistance mechanisms were explored through the publicly available platforms from the Center for Genomic Epidemiology. Twenty-four carbapenem-resistant E. coli isolates were screened out from 2,993 E. coli clinical isolates and all carbapenem-resistant isolates showed multiple drug-resistant phenotypes. The main serotypes identified among carbapenem-resistant isolates through WGS included E. coli O8:H21 (n = 6), E. coli O102:H6 (n = 6), and E. coli O25:H4 (n = 3), and the dominant sequence types (ST) were ST410 (n = 8), ST405 (n = 6), and ST131 (n = 3). Carbapenemase encoding genes, including blaIMP-4 (n = 3), blaKPC-2 (n = 2), blaNDM-5 (n = 1), and blaIMP-1 (n = 1) were identified in seven isolates. WGS analysis could provide a vast amount of molecular epidemiological data of the resistant isolates all at once, such as serotypes, multilocus sequence typing (MLST) types, plasmid replicons, and resistant determinants. Since carbapenem is the last resort to treat life-threatening E. coli infections, it is urgent to characterize the transmission routes and develop risk management strategies to block or slow down the transmission of resistance mechanisms and save carbapenems.

  20. Evaluation of antimicrobial susceptibility of Escherichia coli strains isolated in Rabat University Hospital (Morocco).

    PubMed

    Alem, Nabil; Frikh, Mohammed; Srifi, Abdellatif; Maleb, Adil; Chadli, Mariama; Sekhsokh, Yassine; Louzi, Lhoucin; Ibrahimi, Azzedine; Lemnouer, Abdelhay; Elouennass, Mostafa

    2015-08-30

    Escherichia coli (E. coli) is the most commonly isolated bacteria in human pathology. In Morocco the data concerning the nature and the rates of antibiotic resistance of E. coli in both hospitals and city environment remains relatively poor and needs further investigations. During a 16 months period, E. coli isolates were collected from different culture specimens received in the Bacteriology Department of the Military teaching Hospital Mohammed-V-Rabat for routine diagnostic purposes. E. coli isolates were identified and their antimicrobial susceptibility pattern was determined. A total of 1369 E. coli isolates comprising 33% (1369/4110) of culture-positive samples were consecutively collected. Isolates of E. coli were, in 40.5% (554/1369) of cases from hospitalized patients and in 59.5% (815/1369) of cases from outpatients. Urine isolates represented 82% (1123/1369) of the cases. High rates of resistance were found for amoxicillin (42.5%), cefalotin (30.4%), norfoloxacin (29.9%) and sulfamethoxazole (37.7%). The detection rate of ESBL was 6.1% (85/1369). In hospitalized patients 11.9% of the isolates of E. coli (66/554) had an ESBL phenotype while in outpatients cases only 2.3% of isolates of E. coli (19/815) had this phenotype. Our findings suggest that more judicious use of antibiotics is needed especially in probabilistic treatment. The emergence of ESBL in the Moroccan cities is an indicator of the severity of this problem that is not limited to health care facilities.

  1. Moderate prevalence of antimicrobial resistance in Escherichia coli isolates from lettuce, irrigation water, and soil.

    PubMed

    Holvoet, Kevin; Sampers, Imca; Callens, Benedicte; Dewulf, Jeroen; Uyttendaele, Mieke

    2013-11-01

    Fresh produce is known to carry nonpathogenic epiphytic microorganisms. During agricultural production and harvesting, leafy greens can become contaminated with antibiotic-resistant pathogens or commensals from animal and human sources. As lettuce does not undergo any inactivation or preservation treatment during processing, consumers may be exposed directly to all of the (resistant) bacteria present. In this study, we investigated whether lettuce or its production environment (irrigation water, soil) is able to act as a vector or reservoir of antimicrobial-resistant Escherichia coli. Over a 1-year period, eight lettuce farms were visited multiple times and 738 samples, including lettuce seedlings (leaves and soil), soil, irrigation water, and lettuce leaves were collected. From these samples, 473 isolates of Escherichia coli were obtained and tested for resistance to 14 antimicrobials. Fifty-four isolates (11.4%) were resistant to one or more antimicrobials. The highest resistance rate was observed for ampicillin (7%), followed by cephalothin, amoxicillin-clavulanic acid, tetracycline, trimethoprim, and streptomycin, with resistance rates between 4.4 and 3.6%. No resistance to amikacin, ciprofloxacin, gentamicin, or kanamycin was observed. One isolate was resistant to cefotaxime. Among the multiresistant isolates (n = 37), ampicillin and cephalothin showed the highest resistance rates, at 76 and 52%, respectively. E. coli isolates from lettuce showed higher resistance rates than E. coli isolates obtained from soil or irrigation water samples. When the presence of resistance in E. coli isolates from lettuce production sites and their resistance patterns were compared with the profiles of animal-derived E. coli strains, they were found to be the most comparable with what is found in the cattle reservoir. This may suggest that cattle are a potential reservoir of antimicrobial-resistant E. coli strains in plant primary production.

  2. Moderate Prevalence of Antimicrobial Resistance in Escherichia coli Isolates from Lettuce, Irrigation Water, and Soil

    PubMed Central

    Holvoet, Kevin; Callens, Benedicte; Dewulf, Jeroen; Uyttendaele, Mieke

    2013-01-01

    Fresh produce is known to carry nonpathogenic epiphytic microorganisms. During agricultural production and harvesting, leafy greens can become contaminated with antibiotic-resistant pathogens or commensals from animal and human sources. As lettuce does not undergo any inactivation or preservation treatment during processing, consumers may be exposed directly to all of the (resistant) bacteria present. In this study, we investigated whether lettuce or its production environment (irrigation water, soil) is able to act as a vector or reservoir of antimicrobial-resistant Escherichia coli. Over a 1-year period, eight lettuce farms were visited multiple times and 738 samples, including lettuce seedlings (leaves and soil), soil, irrigation water, and lettuce leaves were collected. From these samples, 473 isolates of Escherichia coli were obtained and tested for resistance to 14 antimicrobials. Fifty-four isolates (11.4%) were resistant to one or more antimicrobials. The highest resistance rate was observed for ampicillin (7%), followed by cephalothin, amoxicillin-clavulanic acid, tetracycline, trimethoprim, and streptomycin, with resistance rates between 4.4 and 3.6%. No resistance to amikacin, ciprofloxacin, gentamicin, or kanamycin was observed. One isolate was resistant to cefotaxime. Among the multiresistant isolates (n = 37), ampicillin and cephalothin showed the highest resistance rates, at 76 and 52%, respectively. E. coli isolates from lettuce showed higher resistance rates than E. coli isolates obtained from soil or irrigation water samples. When the presence of resistance in E. coli isolates from lettuce production sites and their resistance patterns were compared with the profiles of animal-derived E. coli strains, they were found to be the most comparable with what is found in the cattle reservoir. This may suggest that cattle are a potential reservoir of antimicrobial-resistant E. coli strains in plant primary production. PMID:23974140

  3. Genotypic study of verocytotoxic Escherichia coli isolates from deer by multiplex polymerase chain reaction

    PubMed Central

    Mishra, Raghavendra Prasad; Jain, Udit; Singh, Rakesh Kumar

    2016-01-01

    Aim: This study was planned to study the genotypes of verocytotoxigenic Escherichia coli (VTEC) in fecal samples of deer due to its public health significance. Materials and Methods: A total of 160 fecal samples of deer were taken from Mathura district and Kanpur Zoo and screened for VTEC genes by polymerase chain reaction (PCR). Results: All fecal samples were positive for E. coli. All the E. coli isolates were screened by PCR to detect virulence genes stx1, stx2, eaeA, and hlyA. Of these, 15 isolates were found positive for VTEC having one or more genes in different combinations. Conclusion: Genes such as stx1, stx2, eaeA, and hlyA were prevalent in VTEC isolates from feces of deer. The presence of VTEC isolates having virulent genes may pose a threat to public health. PMID:27651685

  4. 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

  5. Antibiotic Resistance Patterns of Escherichia coli Isolates from Hospitals in Kumasi, Ghana

    PubMed Central

    George, Duredoh Freeman; Gbedema, Stephen Yao; Agyare, Christian; Adu, Francis; Boamah, Vivian Etsiapa; Tawiah, Adelaide Ama; Saana, Sixtus Bieranye Bayaa Martin

    2012-01-01

    Nosocomial infections are infections acquired by a patient as a result of treatment in a hospital or healthcare service providing center and symptoms occurs within a short period of hospitalization. The study was to determine the antibiotic resistance patterns of Escherichia coli isolated from Kumasi-South, Tafo and Suntreso Hospitals, Kumasi, Ghana. Total of 600 swabs samples from the hospitals were collected between January and June, 2010. The isolates were identified using morphological and biochemical means. A total of 97 E. coli isolates were obtained from the hospitals. Beds in hospital wards had the highest number of E. coli strains (53.6%), followed by floors (20.6%) while drainages had the least isolates (3.1%). Majority of the E. coli isolates (90.7%) exhibited resistance to ampicillin while 6.2 and 3.1% showed intermediate and sensitive respectively. Co-trimoxazole, 78.4% of the isolates were resistant while 9.3 and 12.4% exhibited intermediate and sensitive responses respectively. E. coli isolates (28.6 to 46.4%) were resistant to gentamicin, ciprofloxacin and ceftriaxone while 14.4 to 47.4% gave intermediate responses. Most isolates (80.4%) exhibited multi-drug resistance. There is a need to observe proper personal hygiene, use of effective disinfectants and proper disposal of contaminated/pathogenic materials in these hospitals to control nosocomial infections. PMID:23762756

  6. Antibiotic Resistance Patterns of Escherichia coli Isolates from Hospitals in Kumasi, Ghana.

    PubMed

    George, Duredoh Freeman; Gbedema, Stephen Yao; Agyare, Christian; Adu, Francis; Boamah, Vivian Etsiapa; Tawiah, Adelaide Ama; Saana, Sixtus Bieranye Bayaa Martin

    2012-01-01

    Nosocomial infections are infections acquired by a patient as a result of treatment in a hospital or healthcare service providing center and symptoms occurs within a short period of hospitalization. The study was to determine the antibiotic resistance patterns of Escherichia coli isolated from Kumasi-South, Tafo and Suntreso Hospitals, Kumasi, Ghana. Total of 600 swabs samples from the hospitals were collected between January and June, 2010. The isolates were identified using morphological and biochemical means. A total of 97 E. coli isolates were obtained from the hospitals. Beds in hospital wards had the highest number of E. coli strains (53.6%), followed by floors (20.6%) while drainages had the least isolates (3.1%). Majority of the E. coli isolates (90.7%) exhibited resistance to ampicillin while 6.2 and 3.1% showed intermediate and sensitive respectively. Co-trimoxazole, 78.4% of the isolates were resistant while 9.3 and 12.4% exhibited intermediate and sensitive responses respectively. E. coli isolates (28.6 to 46.4%) were resistant to gentamicin, ciprofloxacin and ceftriaxone while 14.4 to 47.4% gave intermediate responses. Most isolates (80.4%) exhibited multi-drug resistance. There is a need to observe proper personal hygiene, use of effective disinfectants and proper disposal of contaminated/pathogenic materials in these hospitals to control nosocomial infections.

  7. 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 stx2 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 stx1 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.

  8. Epidemiological survey of the enteropathogenic Escherichia coli isolated from children with diarrhoea.

    PubMed

    Regua, A H; Bravo, V L; Leal, M C; Lobo Leite, M E

    1990-08-01

    Escherichia coli was isolated in 382 (94 per cent) of 406 children from 0 to 3 years of age who had been hospitalized for diarrhoea at the Hospital Municipal Salles Neto, Rio de Janeiro. Enteropathogenic Escherichia coli strains were isolated in 67 samples (18 per cent), distributed among the serogroups that were tested as follows: 0111 (33 per cent); 0125 (19 per cent); 0126, 0127, and 0142 (9 per cent); 0128 and 0119 (8 per cent); 055 (5 per cent); 0114 (2 per cent). No strains of EPEC belonging to serogroups 086, 0126, and 0158 were found. Among the samples in which EPEC strains were isolated, 15.0 per cent were children living in dwellings which had piped systems of water supply and drain, whereas with regard to those living in houses without such facilities, this percentage raised to 24 per cent. Similar results were found when the availability of water supply of drainage were taken separately.

  9. Molecular screening of pathogenic Escherichia coli strains isolated from dairy neonatal calves in Cordoba province, Argentina.

    PubMed

    Picco, Natalia Y; Alustiza, Fabrisio E; Bellingeri, Romina V; Grosso, María C; Motta, Carlos E; Larriestra, Alejandro J; Vissio, Claudina; Tiranti, Karina I; Terzolo, Horacio R; Moreira, Ana R; Vivas, Adriana B

    2015-01-01

    The aim of this study was to perform a current molecular characterization of bovine pathogenic Escherichia coli strains isolated from random samplings in Argentinean dairy farms. Rectal swabs were obtained from 395 (63.7%) healthy and 225 (36.3%) diarrheic calves, belonging to 45 dairy farms in Cordoba Province, Argentina. E. coli isolates were examined for virulence genes (f5, f41, f17, sta, stb, lt, eae, vt) using PCR and the prevalence of E. coli virulence profiles was spatially described in terms of spatial distribution. A total of 30.1% isolates were found to be positive for at least one of the virulence genes. Depending on the different gene combinations present, 11 virulence profiles were found. Most of the isolates analyzed had a single gene, and no combination of fimbrial and enterotoxin gene was predominant. There was no association between the frequency and distribution of E. coli virulence genes and calf health status. Most of the virulence profiles were compatible with ETEC strains and showed a homogeneous distribution over the sampled area. A clustering pattern for E. coli virulence profiles could not be recognized. This work provides updated information on the molecular characterization of pathogenic E. coli strains from dairy herds in Cordoba, Argentina. These findings would be important to formulate prevention programs and effective therapies for diarrhea in calves caused by E. coli. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Antimicrobial resistance changes in enteric Escherichia coli of horses during hospitalisation: resistance profiling of isolates.

    PubMed

    Williams, A; Christley, R M; McKane, S A; Roberts, V L H; Clegg, P D; Williams, N J

    2013-01-01

    The aim of this study was to determine whether hospitalisation of horses leads to increased antimicrobial resistance in equine faecal Escherichia coli isolates. E. coli were cultured from faecal samples of horses on admission and after 7 days of hospitalisation; antimicrobial susceptibility was determined for eight antimicrobial agents. Resistance profiles of E. coli isolates were grouped into clusters, which were analysed to determine resistance patterns. Resistance to 7/8 antimicrobial agents and multi-drug resistance (MDR; resistance to ≥3 antimicrobial classes) were significantly higher after 7 days of hospitalisation. Forty-eight resistance profiles were identified; 15/48 were present on day 0 only, 16/48 on day 7 only and 17/48 at both times of sampling. There was a significant association between day 7 profiles and resistance detected to an increased number of antimicrobial agents. Hospitalisation of horses for 7 days resulted in alterations in equine faecal E. coli antimicrobial resistance profiles.

  11. Molecular Epidemiology of Ceftiofur-Resistant Escherichia coli Isolates from Dairy Calves

    PubMed Central

    Donaldson, Sarah C.; Straley, Beth A.; Hegde, Narasimha V.; Sawant, Ashish A.; DebRoy, Chitrita; Jayarao, Bhushan M.

    2006-01-01

    Healthy calves (n = 96, 1 to 9 weeks old) from a dairy herd in central Pennsylvania were examined each month over a five-month period for fecal shedding of ceftiofur-resistant gram-negative bacteria. Ceftiofur-resistant Escherichia coli isolates (n = 122) were characterized by antimicrobial resistance (disk diffusion and MIC), serotype, pulsed-field gel electrophoresis subtypes, beta-lactamase genes, and virulence genes. Antibiotic disk diffusion assays showed that the isolates were resistant to ampicillin (100%), ceftiofur (100%), chloramphenicol (94%), florfenicol (93%), gentamicin (89%), spectinomycin (72%), tetracycline (98%), ticarcillin (99%), and ticarcillin-clavulanic acid (99%). All isolates were multidrug resistant and displayed elevated MICs. The E. coli isolates belonged to 42 serotypes, of which O8:H25 was the predominant serotype (49.2%). Pulsed-field gel electrophoresis classified the E. coli isolates into 27 profiles. Cluster analysis showed that 77 isolates (63.1%) belonged to one unique group. The prevalence of pathogenic E. coli was low (8%). A total of 117 ceftiofur-resistant E. coli isolates (96%) possessed the blaCMY2 gene. Based on phenotypic and genotypic characterization, the ceftiofur-resistant E. coli isolates belonged to 59 clonal types. There was no significant relationship between calf age and clonal type. The findings of this study revealed that healthy dairy calves were rapidly colonized by antibiotic-resistant strains of E. coli shortly after birth. The high prevalence of multidrug-resistant nonpathogenic E. coli in calves could be a significant source of resistance genes to other bacteria that share the same environment. PMID:16751500

  12. Isolation of Escherichia coli O157:H7 from retail fresh meats and poultry.

    PubMed Central

    Doyle, M P; Schoeni, J L

    1987-01-01

    A total of 896 samples of retail fresh meats and poultry was assayed for Escherichia coli serogroup O157:H7 by a hydrophobic grid membrane filter-immunoblot procedure developed specifically to isolate the organism from foods. The procedure involves several steps, including selective enrichment, filtration of enrichment culture through hydrophobic grid membrane filters, incubation of each filter on nitrocellulose paper on selective agar, preparation of an immunoblot (by using antiserum to E. coli O157:H7 culture filtrate) of each nitrocellulose paper, selection from the filters of colonies which corresponded to immunopositive sites on blots, screening of isolates by a Biken test for precipitin lines from metabolites and antiserum to E. coli O157:H7 culture filtrate, and confirmation of isolates as Vero cell cytotoxic E. coli O157:H7 by biochemical, serological, and Vero cell cytotoxicity tests. E. coli O157:H7 was isolated from 6 (3.7%) of 164 beef, 4 (1.5%) of 264 pork, 4 (1.5%) of 263 poultry, and 4 (2.0%) of 205 lamb samples. One of 14 pork samples and 5 of 17 beef samples contaminated with the organism were from Calgary, Alberta, Canada, grocery stores, whereas all other contaminated samples were from Madison, Wis., retail outlets. This is the first report of the isolation of E. coli O157:H7 from food other than ground beef, and results indicate that the organism is not a rare contaminant of fresh meats and poultry. Images PMID:3322190

  13. 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.

  14. Detection of virulence genes in Escherichia coli isolated from patients with cystitis and pyelonephritis.

    PubMed

    Firoozeh, Farzaneh; Saffari, Mahmood; Neamati, Foroogh; Zibaei, Mohammad

    2014-12-01

    Uropathogenic Escherichia coli (UPEC) is a common cause of ascending urinary tract infections including cystitis and pyelonephritis. The purpose of this study was to investigate virulence genes among Escherichia coli isolated from patients with cystitis and pyelonephritis. Between December 2012 and June 2013, 150 E. coli isolates from hospitalized patients with pyelonephritis (n = 72) and cystitis (n=78) were collected at Shahid Beheshti Hospital in Kashan. A PCR assay was used to evaluate the presence of virulence genes including pap, hly, aer, sfa, cnf, afa, traT, and pathogenicity island (PAI) markers in isolates. Of the total 150 UPEC isolates, 130 (86.7%) were found to carry the virulence genes studied. Nineteen different virulence patterns were identified. The most prevalent virulence pattern was UPEC including traT-PAI operons. The pap, traT, aer, hly, and PAI operons were more prevalent among patients with pyelonephritis than cystitis, and the sfa, afa, and cnf genes were not detected in any of the isolates. Higher virulence gene diversity was found among pyelonephritis UPEC isolates in comparison to cystitis UPEC isolates, showing that UPEC strains that cause pyelonephritis need more virulence factors. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Genomic and molecular analysis of the hyperadherent phenotype of an Escherichia coli O157:H7 super shedder isolate

    USDA-ARS?s Scientific Manuscript database

    Shiga Toxin producing Escherichia coli (STEC) are a subtype of pathogenic E. coli and, in particular, STEC isolates of E. coli serotype O157:H7 are recognized as a major foodborne pathogen that can cause infections ranging from having simple intestinal discomfort to bloody diarrhea and life threaten...

  16. Draft Genome Sequences of Semiconstitutive Red, Dry, and Rough Biofilm-Forming Commensal and Uropathogenic Escherichia coli Isolates

    PubMed Central

    Cimdins, Annika; Lüthje, Petra; Li, Fengyang; Ahmad, Irfan; Brauner, Annelie

    2017-01-01

    ABSTRACT Strains of Escherichia coli exhibit diverse biofilm formation capabilities. E. coli K-12 expresses the red, dry, and rough (rdar) morphotype below 30°C, whereas clinical isolates frequently display the rdar morphotype semiconstitutively. We sequenced the genomes of eight E. coli strains to subsequently investigate the molecular basis of semiconstitutive rdar morphotype expression. PMID:28126929

  17. Sharing of Ribotype Patterns of Escherichia Coli Isolates During Baseflow and Stormflow Conditions

    USGS Publications Warehouse

    Hartel, Peter G.; Frick, Elizabeth A.; Funk, Adrienne L.; Hill, Jennifer L.; Summer, Jacob D.; Gregory, M. Brian

    2004-01-01

    Factors affecting bacterial source tracking are important to understand because they affect the amount of sampling needed to describe fecal sources in a watershed adequately. The study area was a 76-kilometer reach of the Chattahoochee River and its tributaries in Metropolitan Atlanta, Georgia. Escherichia coli was isolated from water samples collected during baseflow and stormflow conditions from four mainstem and eight tributary sites; 262 isolates were ribotyped and assessed for their similarity. The vast majority of the E. coli ribotype patterns were unshared, whether the comparisons were between baseflow and stormflow conditions at one location, or between one location and another. The data suggest that either baseflow and stormflow conditions affected sharing of ribotype patterns, or that the sample size was too small to characterize the sharing adequately. Regardless, the results suggest that a large sampling of E. coli isolates is needed during various flow conditions from watersheds with complex land-use patterns for adequate bacterial source tracking.

  18. Efficacy of fosfomycin on Escherichia coli isolated from bitches with pyometra.

    PubMed

    Inoue, Ikuo; Shibata, Sanae; Fukata, Tsuneo

    2013-01-01

    The aim of this study was to determine the antimicrobial resistance of Escherichia coli isolated from the uteri of bitches with pyometra, and 38 E. coli isolates were used. The antimicrobials used were ampicillin (ABPC), amoxicillin/clavulanic acid, gentamicin, minocycline, cefazolin, levofloxacin (LVFX), trimethoprim-sulfamethoxazole (ST) and fosfomycin (FOM). Resistance to ABPC occurred most frequently, followed by LVFX and ST. Multi-drug resistance, defined as resistance against 3 or more classes of antimicrobials, was found in 23.7% of all isolates. Nine out of 13 resistant strains were multi-drug resistant, but no strain was found to be resistant to FOM. This suggests that FOM should be administered for E. coli from pyometra.

  19. Detection of mutations in parC in quinolone-resistant clinical isolates of Escherichia coli.

    PubMed Central

    Vila, J; Ruiz, J; Goñi, P; De Anta, M T

    1996-01-01

    The gene parC encodes the A subunit of topoisomerase IV of Escherichia coli. Mutations in the parC region analogous to those in the quinolone resistance-determining region of gyrA were investigated in 27 clinical isolates of E. coli for which ciprofloxacin MICs were 0.0007 to 128 micrograms/ml. Of 15 isolates for which ciprofloxacin MICs were > or = 1 microgram/ml, 8 showed a change in the serine residue at position 80 (Ser-80), 4 showed a change in Glu-84, and 3 showed changes in both amino acids. No mutations were detected in 12 clinical isolates for which ciprofloxacin MICs were < or = 0.25 micrograms/ml. These findings suggest that ParC from E. coli may be another target for quinolones and that mutations at residues Ser-80 and Glu-84 may contribute to decreased fluoroquinolone susceptibility. PMID:8834907

  20. 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

  1. 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

  2. Characterization of Escherichia coli O157:H7 Strains Isolated from Supershedding Cattle

    PubMed Central

    Ahmed, Rafiq; Chase-Topping, Margo; Kalchayanand, Norasak; Schmidt, John W.; Bono, James L.

    2013-01-01

    Previous reports have indicated that a small proportion of cattle shedding high levels of Escherichia coli O157:H7 is the main source for transmission of this organism between animals. Cattle achieving a fecal shedding status of 104 CFU of E. coli O157:H7/gram or greater are now referred to as supershedders. The aim of this study was to investigate the contribution of E. coli O157:H7 strain type to supershedding and to determine if supershedding was restricted to a specific set of E. coli O157:H7 strains. Fecal swabs (n = 5,086) were collected from cattle at feedlots or during harvest. Supershedders constituted 2.0% of the bovine population tested. Supershedder isolates were characterized by pulsed-field gel electrophoresis (PFGE), phage typing, lineage-specific polymorphism assay (LSPA), Stx-associated bacteriophage insertion (SBI) site determination, and variant analysis of Shiga toxin, tir, and antiterminator Q genes. Isolates representing 52 unique PFGE patterns, 19 phage types, and 12 SBI clusters were obtained from supershedding cattle, indicating that there is no clustering to E. coli O157:H7 genotypes responsible for supershedding. While being isolated directly from cattle, this strain set tended to have higher frequencies of traits associated with human clinical isolates than previously collected bovine isolates with respect to lineage and tir allele, but not for SBI cluster and Q type. We conclude that no exclusive genotype was identified that was common to all supershedder isolates. PMID:23645203

  3. Characterization of Escherichia coli O157:H7 strains isolated from supershedding cattle.

    PubMed

    Arthur, Terrance M; Ahmed, Rafiq; Chase-Topping, Margo; Kalchayanand, Norasak; Schmidt, John W; Bono, James L

    2013-07-01

    Previous reports have indicated that a small proportion of cattle shedding high levels of Escherichia coli O157:H7 is the main source for transmission of this organism between animals. Cattle achieving a fecal shedding status of 10(4) CFU of E. coli O157:H7/gram or greater are now referred to as supershedders. The aim of this study was to investigate the contribution of E. coli O157:H7 strain type to supershedding and to determine if supershedding was restricted to a specific set of E. coli O157:H7 strains. Fecal swabs (n = 5,086) were collected from cattle at feedlots or during harvest. Supershedders constituted 2.0% of the bovine population tested. Supershedder isolates were characterized by pulsed-field gel electrophoresis (PFGE), phage typing, lineage-specific polymorphism assay (LSPA), Stx-associated bacteriophage insertion (SBI) site determination, and variant analysis of Shiga toxin, tir, and antiterminator Q genes. Isolates representing 52 unique PFGE patterns, 19 phage types, and 12 SBI clusters were obtained from supershedding cattle, indicating that there is no clustering to E. coli O157:H7 genotypes responsible for supershedding. While being isolated directly from cattle, this strain set tended to have higher frequencies of traits associated with human clinical isolates than previously collected bovine isolates with respect to lineage and tir allele, but not for SBI cluster and Q type. We conclude that no exclusive genotype was identified that was common to all supershedder isolates.

  4. EcoR phylogenetic analysis and virulence genotyping of avian pathogenic Escherichia coli strains and Escherichia coli isolates from commercial chicken carcasses in southern Brazil.

    PubMed

    Kobayashi, Renata K T; Aquino, Ivani; Ferreira, Ana Lívia da S; Vidotto, Marilda C

    2011-05-01

    Escherichia coli strains designated as avian pathogenic E. coli (APEC) are responsible for avian colibacillosis, an acute and largely systemic disease that promotes significant economic losses in poultry industry worldwide because of mortality increase, medication costs, and condemnation of carcasses. APEC is a subgroup of extraintestinal pathogenic E. coli pathotype, which includes uropathogenic E. coli, neonatal meningitis E. coli, and septicemic E. coli. We isolated E. coli from commercial chicken carcasses in a Brazilian community and compared by polymerase chain reaction-defined phylogenetic group (A, B1, B2, or D) with APEC strains isolated from sick chickens from different poultry farms. A substantial number of strains assigned to phylogenetic E. coli reference collection group B2, which is known to harbor potent extraintestinal human and animal E. coli pathogens, were identified as APEC (26.0%) in both commercial chicken carcasses and retail poultry meat (retail poultry E. coli [RPEC]) (21.25%). The majority of RPEC were classified as group A (35%), whereas the majority of APEC were groups B1 (30.8) and A (27.6%). APEC and RPEC presented the genes pentaplex, iutA, hly, iron, ompT, and iss, but with different virulence profiles. The similarity between APEC and RPEC indicates RPEC as potentially pathogenic strains and supports a possible zoonotic risk for humans.

  5. Isolation and Characterization of Intestinal Escherichia coli Clones from Wild Boars in Germany▿ †

    PubMed Central

    Schierack, Peter; Römer, Antje; Jores, Jörg; Kaspar, Heike; Guenther, Sebastian; Filter, Matthias; Eichberg, Jürgen; Wieler, Lothar H.

    2009-01-01

    Our understanding of the composition of Escherichia coli populations in wild boars is very limited. In order to obtain insight into the E. coli microflora of wild boars, we studied E. coli isolates from the jejunums, ileums, and colons of 21 wild boars hunted in five geographic locations in Germany. Ten isolates per section were subjected to clonal determination using pulsed-field gel electrophoresis. One representative isolate per clone was further investigated for virulence traits, phylogenetic affiliation, and antimicrobial susceptibility. Macrorestriction analysis of 620 isolates revealed a range of clone diversity among the sections and animals, with up to 9 and 16 different clones per section and animal, respectively. Most of the clones for a given animal were shared between two adjacent intestinal sections. The overall highest clonal diversity was observed within the colon. While the astA gene was present in a large number of clones, other virulence genes and hemolytic ability were detected only sporadically. Clones of all four ECOR groups dominated the intestinal sections. Phylogenetic analysis and the occurrence of virulence genes correlated with the isolation frequencies for clones. All E. coli clones from wild boars were susceptible to all antimicrobial agents tested. In conclusion, though several parameters (including an animal-specific and highly diverse E. coli clone composition, the simultaneous occurrence of single clones in two adjacent intestinal sections of a given animal, and a higher E. coli diversity in the large intestine than in the small intestine) of E. coli populations of wild boars were similar to those of previously described E. coli populations of conventionally reared domestic pigs, our data also indicate possible differences, as seen for the E. coli diversity in the large intestine, the occurrence of certain virulence genes and phylogenetic groups, and antimicrobial susceptibilities. PMID:19060173

  6. Virulence characterization of Shiga-toxigenic Escherichia coli isolates from wholesale produce.

    PubMed

    Feng, Peter C H; Councell, Terry; Keys, Christine; Monday, Steven R

    2011-01-01

    The 13 Shiga-toxigenic Escherichia coli (STEC) strains isolated from wholesale spinach and lettuce consisted mostly of serotypes that have not been implicated in illness. Among these strains, however, were two O113:H21 that carried virulence genes common to this pathogenic serotype (stx(2), ehxA, saa, and subAB), suggesting that their presence in ready-to-eat produce may be of health concern.

  7. Development of resistance with host age to adhesion of K99+ Escherichia coli to isolated intestinal epithelial cells.

    PubMed Central

    Runnels, P L; Moon, H W; Schneider, R A

    1980-01-01

    When isolated intestinal epithelial cells from neonatal and older pigs, calves, and mice were tested for adhesion by K99+ enterotoxigenic Escherichia coli, cells from older animals were resistant to adhesion. PMID:6103878

  8. 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 blaCTX-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

  9. Genetic probes for enterotoxigenic Escherichia coli isolated from childhood diarrhea in the Central African Republic.

    PubMed Central

    Georges, M C; Wachsmuth, I K; Birkness, K A; Moseley, S L; Georges, A J

    1983-01-01

    Escherichia coli strains were isolated from 778 children with diarrhea and 151 well children in the Central African Republic over a period of 1 year. These 929 strains were assayed for heat-labile and heat-stable enterotoxin production and were hybridized (probed) with structural genes for these enterotoxins. Twenty-four isolates from diarrheal patients and one isolate from a well child were found to be toxigenic by assay and probe. Minor discrepancies were encountered with both assays and probes during initial screening procedures, but the two methodologies were ultimately comparable. Images PMID:6350346

  10. Antimicrobial resistance profiles among Escherichia coli strains isolated from commercial and cooked foods.

    PubMed

    Ryu, Seung-Hee; Lee, Jip-Ho; Park, Sang-Hoon; Song, Mi-Ok; Park, Sun-Hee; Jung, Hyo-Won; Park, Geon-Yong; Choi, Sung-Min; Kim, Moo-Sang; Chae, Young-Zoo; Park, Seog-Gee; Lee, Young-Ki

    2012-10-15

    A total of 4330 food samples of which microbiological standard for Escherichia coli is negative in Korea were determined for the frequency of E. coli. Ninety six samples (2.2%) were positive for E. coli. Detection rate of E. coli varied significantly by food type and ranged from 0.3% to 10.9%. Seasoned raw meat (yukhoe) and cold bean-soup had the highest prevalence for E. coli (10.9%) followed by gimbap (5.2%), meat broth for cold noodle (2.9%) and sprout (2.1%). E. coli isolates (n=96) were investigated for their phenotypic and genotypic antimicrobial resistance patterns. Seventeen E. coli isolates (17.7%) were resistant to one or more antimicrobial agents tested. High rates of resistance to the following drugs were observed: tetracycline (15.6%), streptomycin (12.5%), ampicillin (10.4%), nalidixic acid (9.4%) and ticarcillin (9.4%). All ampicillin resistant isolates were screened for extended-spectrum β-lactamase (ESBL) production by the combination disk test. None of the E. coli isolates produced ESBLs. Seventeen out of 96 E. coli isolates which were resistant to at least one antibiotic were investigated by PCR for the presence of 3 classes of antimicrobial resistance genes (tetracycline, aminoglycosides and beta-lactams). The tetracycline resistance genes tetA and tetB were found in 7 and 5 isolates, respectively. The aminoglycoside resistance genes, strA/B, aphA1, aadA and aac(3)-IV were found in 9, 5, 2 and 2 isolates, respectively. The beta-lactam resistance gene, bla(TEM) was found in 7 isolates. Results of this study show that 13 E. coli isolates were multidrug resistant (to three or more antibiotics) and 12 isolates carried at least one antimicrobial resistance gene. These isolates can act as the reservoir for antimicrobial resistance genes and facilitate the dissemination of these genes to other pathogenic and commensal bacteria. Adequate intervention to reduce microbial contamination of these foods is strongly recommended.

  11. 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

  12. Emergence of an NDM-5-producing clinical Escherichia coli isolate in Egypt.

    PubMed

    Soliman, Ahmed M; Khalifa, Hazim O; Ahmed, Ashraf M; Shimamoto, Toshi; Shimamoto, Tadashi

    2016-07-01

    The first occurrence of New Delhi metallo-β-lactamase 5 (NDM-5), carried on an IncI1-Iγ-type plasmid of >93kb in a multidrug-resistant Escherichia coli strain in Kafr El-Sheikh, Egypt, is reported. The strain was isolated from a wound pus swab from a patient diagnosed with a fracture of the right femur. This E. coli strain was found to belong to sequence type (ST) 5018 and also to carry other resistance genes, including blaCTX-M-15, blaCMY-42, blaOXA-1, and aac(6')-Ib-cr.

  13. Characterization of Environmentally Persistent Escherichia coli Isolates Leached from an Irish Soil▿

    PubMed Central

    Brennan, Fiona P.; Abram, Florence; Chinalia, Fabio A.; Richards, Karl G.; O'Flaherty, Vincent

    2010-01-01

    Soils are typically considered to be suboptimal environments for enteric organisms, but there is increasing evidence that Escherichia coli populations can become resident in soil under favorable conditions. Previous work reported the growth of autochthonous E. coli in a maritime temperate Luvic Stagnosol soil, and this study aimed to characterize, by molecular and physiological means, the genetic diversity and physiology of environmentally persistent E. coli isolates leached from the soil. Molecular analysis (16S rRNA sequencing, enterobacterial repetitive intergenic consensus PCR, pulsed-field gel electrophoresis, and a multiplex PCR method) established the genetic diversity of the isolates (n = 7), while physiological methods determined the metabolic capability and environmental fitness of the isolates, relative to those of laboratory strains, under the conditions tested. Genotypic analysis indicated that the leached isolates do not form a single genetic grouping but that multiple genotypic groups are capable of surviving and proliferating in this environment. In physiological studies, environmental isolates grew well across a broad range of temperatures and media, in comparison with the growth of laboratory strains. These findings suggest that certain E. coli strains may have the ability to colonize and adapt to soil conditions. The resulting lack of fecal specificity has implications for the use of E. coli as an indicator of fecal pollution in the environment. PMID:20154122

  14. Characterization of environmentally persistent Escherichia coli isolates leached from an Irish soil.

    PubMed

    Brennan, Fiona P; Abram, Florence; Chinalia, Fabio A; Richards, Karl G; O'Flaherty, Vincent

    2010-04-01

    Soils are typically considered to be suboptimal environments for enteric organisms, but there is increasing evidence that Escherichia coli populations can become resident in soil under favorable conditions. Previous work reported the growth of autochthonous E. coli in a maritime temperate Luvic Stagnosol soil, and this study aimed to characterize, by molecular and physiological means, the genetic diversity and physiology of environmentally persistent E. coli isolates leached from the soil. Molecular analysis (16S rRNA sequencing, enterobacterial repetitive intergenic consensus PCR, pulsed-field gel electrophoresis, and a multiplex PCR method) established the genetic diversity of the isolates (n = 7), while physiological methods determined the metabolic capability and environmental fitness of the isolates, relative to those of laboratory strains, under the conditions tested. Genotypic analysis indicated that the leached isolates do not form a single genetic grouping but that multiple genotypic groups are capable of surviving and proliferating in this environment. In physiological studies, environmental isolates grew well across a broad range of temperatures and media, in comparison with the growth of laboratory strains. These findings suggest that certain E. coli strains may have the ability to colonize and adapt to soil conditions. The resulting lack of fecal specificity has implications for the use of E. coli as an indicator of fecal pollution in the environment.

  15. Incidence and toxin production ability of Escherichia coli O157:H7 isolated from cattle trucks.

    PubMed

    Cuesta Alonso, E P; Gilliland, S E; Krehbiel, C R

    2007-10-01

    Twelve cattle trucks were analyzed for the presence of Escherichia coli O157:H7. Three of them had been washed prior to arrival, and the others had not. Seventy-five percent of the trailers were positive for the presence of this foodborne pathogen. A total of 54 cultures were isolated and identified as E. coli O157:H7, all from the trucks that had not been cleaned. Most of the cultures (96.4%) produced Shiga-like toxin (verotoxin). No E. coli O157:H7 was detected in cattle trucks that were cleaned before arrival at the cattle pens. The incidence of E. coli O157:H7 in transport trailers increases the potential risk of contamination of cattle and transmission from farms to feedlots and to packing plants. This contamination increases the potential of contamination of meat during harvest and the risk of foodborne illnesses.

  16. Primary isolation of Shiga toxigenic Escherichia coli from environmental sources

    USDA-ARS?s Scientific Manuscript database

    Since the time of the first microbe hunters, primary culture and isolation of bacteria has been a foundation of microbiology. Like other microbial methods, bacterial culture and isolation methodologies continue to develop. Although fundamental concepts like selection and enrichment are as relevant t...

  17. Antibacterial Activity of Some Plant Extracts Against Extended- Spectrum Beta-Lactamase Producing Escherichia coli Isolates

    PubMed Central

    Saeidi, Saeide; Amini Boroujeni, Negar; Ahmadi, Hassan; Hassanshahian, Mehdi

    2015-01-01

    Background: The extended-spectrum beta-lactamase (ESBL) -producing Escherichia coli isolates make many serious infections, especially urinary tract infections. Objectives: The purpose of this study was to determine the antibacterial activities of some natural plant extracts against ESBL-producing E. coli isolates, which harbor the TEM gene in urine samples of the patients who have urinary tract infections. Materials and Methods: Evaluation has to be exactly determined for both methods of disk diffusion test and polymerase chain reaction (PCR), separately. We evaluated 120 strains of E. coli isolates from the urine culture of the patients in Boo-Ali Hospital (Zahedan, south-eastern Iran) who were suffering from urinary tract infections. The ESBL-producing E. coli isolates were evaluated by disk diffusion test and PCR through TEM gene detection. The minimal inhibitory concentration (MIC) of commonly used antibiotics including ceftazidime, ceftriaxon, amikacin, gentamicin and ciprofloxacin along with the MIC of the alcoholic extract of different natural plants including Myrtus communis L (Myrtaceae), Amaranthus retraflexus (Amaranthaceae), Cyminum cuminum L (Apiaceae), Marrubium vulgare (Laminaceae) and Peganum. harmala (Zygrophyllaceae) against the ESBL-producing E. coli isolates, which harbor the TEM genes, were determined using the microdulition method. Results: Results of this study showed that in disk diffusion method, 80 samples of E. coli produced ESBLs. In PCR method, the TEM gene distribution in the isolated ESBL-producing organisms was 50 (41.6%). Amikacin was the most effective anti-bacterial agent and ciprofloxacin was the least effective against E. coli isolates. All the natural plant extracts mentioned above, especially P. harmala, were effective against the selected isolates of ESBL-producing E. coli. The most frequent ESBL rate producing E. coli isolates (32 out of 50) had MIC of 2.5 mg/mL in ethanol extract of P. harmala. Conclusions: The alcoholic

  18. Prevalence of ESBL in Escherichia coli Isolates Among ICU Patients in a Tertiary Care Hospital

    PubMed Central

    Pattnaik, Dipti; Neogi, Dhruba Kumar; Jena, Jagadananda; Mallick, Bandana

    2016-01-01

    Introduction Resistance to common antibiotics is a matter of grave concern in treating infections in hospital settings especially in Intensive Care Units (ICUs). One of the most commonly used and effective group of antibiotics, cephalosporins, exhibit resistance due to production of Extended Spectrum Beta- Lactamases (ESBLs). The prevalence of ESBL producing Escherichia coli (E.coli) has increased throughout the world and is a major cause of treatment failure in ICUs. As per our knowledge studies were not available on the prevalence of ESBL producing E.coli in ICUs of this region. Aim To determine the prevalence of ESBLs among Escherichia coli isolates in ICUs of a tertiary care hospital. Materials and Methods A cross sectional study was conducted over a period of 4 years (Sept 2011 to Sept 2015) in the Department of Microbiology, Kalinga Institute of Medical Sciences (KIMS), Bhubaneswar. Consecutive non-duplicate isolates of E.coli recovered from 6800 clinical samples of patients admitted to different Intensive Care Units (ICUs) were subjected to ESBL screening test and then to CLSI recommended Phenotypic Confirmatory Disc Diffusion Tests (PCDDT) for ESBL production determination. Results Out of 6800 samples, 1038 were E.coli isolates and 452(44%) were resistant to third generation cephalosporins. ESBL producing Escherichia coli among them were 276 (61.1%). Paediatric ICU showed the highest prevalence of ESBL E.coli at 80.9%. The highest prevalence of ESBL E.coli was in urine samples (82.6%) followed by pus (9.8%). The most effective antibiotic for ESBL producers was imipenem (96.7% sensitive), followed by amikacin (88.4%) and piperacillin- tazobactum (87%). Conclusion This study has highlighted the high prevalence of ESBL producing E.coli in the ICUs of our hospital. An in depth analysis of their antibiogram will be helpful in formulating the antibiotic policy and prevent spread of ESBL strains. It is recommended that ESBL testing should be done routinely to

  19. Genetic background of Escherichia coli isolates from peritoneal dialysis patients with peritonitis and uninfected control subjects.

    PubMed

    Li, Y F; Su, N; Chen, S Y; Hu, W X; Li, F F; Jiang, Z P; Yu, X Q

    2016-03-28

    Escherichia coli is the most common cause of Gram-negative peritonitis resulting in peritoneal function deterioration as well as poor clinical outcome in continuous ambulatory peritoneal dialysis (PD) patients. In this study, we analyzed the phylogenetic background and genetic profile of the E. coli isolates and sought to determine the characteristics of specific bacteria associated with peritonitis. E. coli isolates from 56 episodes of peritonitis in 46 PD patient cases and rectal isolates from 57 matched PD control patient cases were compared for both phylogenetic groups and the presence of virulence factors (VFs). There were no significant differences in terms of demographic data between the peritonitis and control groups. Peritonitis isolates exhibited a significantly greater prevalence of 8 VFs. In multivariate logistic regression analysis, kpsMT II (group 2 capsule synthesis) was the strongest VF predictor of peritonitis (OR = 8.02; 95%CI = 3.18-20.25; P < 0.001), followed by traT (serum-resistance-associated outer membrane protein) (OR = 3.83; 95%CI = 1.33-11.03; P = 0.013). The pathogenic groups of E. coli contained a higher concentration of individual VFs compared to the commensal groups. The prevalence of pathogenic E. coli was much higher in peritoneal isolates than rectal isolates (64.3 vs 31.6%, P = 0.001). Our results indicate that the E. coli peritonitis and rectal isolates are different in PD patients. The specific VFs associated with peritonitis isolates may directly contribute to the pathogenesis of peritonitis.

  20. Extended-spectrum β-lactamase producing Escherichia coli isolated from wild birds in Saskatoon, Canada.

    PubMed

    Parker, D; Sniatynski, M K; Mandrusiak, D; Rubin, J E

    2016-07-01

    The epidemiology of antimicrobial resistance is extremely complex and involves humans, domestic animals (companion and agricultural) and wildlife. In North America there have been very few investigations targeting antimicrobial-resistant organisms in wildlife. In this study, we characterized the susceptibility of Escherichia coli isolated from 75 birds including great horned owls, crows and American robins from the region of Saskatoon, Canada. The recovery rate of E. coli varied significantly between species from 44·8% of robins to 92% of crows. The majority (88·2%) of colonized birds carried only pan-susceptible organisms. Among isolates resistant to at least one antimicrobial, ampicillin resistance was most commonly identified. Three birds carried multidrug-resistant isolates (resistant to ≥3 drug classes), and extended-spectrum β-lactamase (ESBL)-producing organisms (CTX-M-15 and SHV2a) were grown from two. We identified a significant relationship between the presence of drug-resistant E. coli and an urban (vs rural) origin of the bird. Our findings suggest that crows, due to their ubiquity and high rate of colonization with E. coli, may be efficient targets for future resistance surveillance studies targeting urban wildlife. Antimicrobial resistance is a global problem affecting people and animals. Few investigations describing the presence drug-resistant organisms in wildlife in North America have been published. In this study, resistant Escherichia coli, including extended-spectrum β-lactamase-producing strains, were isolated from wild birds in the Saskatoon region of Canada. We found that the recovery rate of E. coli varied significantly by species and was highest among crows. There was also a significant association between drug resistance and urban vs rural birds. Our results suggest that crows may be a good target for future studies investigating antimicrobial resistance in urban wildlife. © 2016 The Society for Applied Microbiology.

  1. Antibiotic Susceptibility and Molecular Characterization of Escherichia coli O157 Isolates from Urinary Tract Infections.

    PubMed

    Xie, Zonglan; Dong, Ziqiang; Zhu, Ping; Zhang, Lusheng; Chen, Xiaobo; Dong, Chuanjiang

    2017-08-16

    Escherichia coli O157 is an important food-borne pathogen that can cause diarrhoea, hemorrhagic colitis, and hemolytic uraemic syndrome. Enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) and multilocus sequence typing (MLST) are good methods for molecular typing and the extensive use of antibiotics is a contributing factor to the increasing incidence of antimicrobial-resistant for these strains. The aim of this study was to determine the prevalence, antimicrobial resistance, and genetic diversity of E. coli O157 based on the prevalence of urinary tract infection (UTI) in Hubei, China. We obtained 23 (8.07%) E. coli O157 isolates from 285 UTI patients in Hubei, China. All isolates were subjected to antibiotic susceptibility analysis, and molecular typing was performed using ERIC-PCR and MLST. Antimicrobial susceptibility results indicated that most strains were resistant to penicillin (95.65%), chloramphenicol (73.91%), and ampicillin (69.57%). All isolates were discovered to be multiresistant (resistance to more than 3 antibiotics). Genetic variability analysis showed that all of the isolates were grouped into 4 clusters both by ERIC-PCR and MLST. Our findings demonstrated the presence of E. coli O157 in UTIs, provided insights into the dissemination of antibiotic-resistant strains, and improved our knowledge of E. coli O157 risk assessment in UTIs. © 2017 S. Karger AG, Basel.

  2. Genetic diversity of Escherichia coli isolates in irrigation water and associated sediments: implications for source tracking.

    PubMed

    Lu, Lingeng; Hume, Michael E; Sternes, Keith L; Pillai, Suresh D

    2004-11-01

    Identifying the sources of fecal contaminants in surface water bodies such as rivers and lakes is of significant importance for environmental quality, food safety and regulatory purposes. Current DNA library-based source tracking approaches rely on the comparison of the genetic relatedness among the fecal contaminants. The objective of this study was to determine the genetic relatedness of Escherichia coli isolated from irrigation water and associated sediments using pulse field gel electrophoresis (PFGE) and to evaluate the genetic stability of the E. coli PFGE patterns. The isolates were obtained over a 4-month period from specific locations within irrigation canals and sediments associated with the Rio Grande River along the Texas-Mexico border. Fifty E. coli isolates were genotyped using PFGE. Different E. coli genotypes were identified among samples collected in 11 different locations. Some isolates obtained over successive months showed similar genotypic patterns. In the laboratory experiment, the PFGE pattern of one E. coli strain changed during survival in irrigation water. The genetic relatedness of this strain changed from >95% to <83% over 8-week survival. These results imply that PFGE is of such extreme resolution that it may be a challenging task to rely solely on a PFGE-based source tracking DNA fingerprint library for large watersheds.

  3. Molecular and phenotypic characterization of Escherichia coli isolated from broiler chicken flocks in Egypt.

    PubMed

    Hussein, Ashraf H M; Ghanem, Ibrahim A I; Eid, Amal A M; Ali, Mohamed A; Sherwood, Julie S; Li, Ganwu; Nolan, Lisa K; Logue, Catherine M

    2013-09-01

    Avian pathogenic Escherichia coli (APEC) infection is responsible for great economic losses to the poultry industry worldwide and there is increasing evidence of its zoonotic importance. In this study, 219 E. coli isolates from 84 poultry flocks in Egypt, including 153 APEC, 30 avian fecal E. coli (AFEC), and 36 environmental E. coli, were subjected to phylogenetic grouping and virulence genotyping. Additionally, 50 of these isolates (30 APEC from colisepticemia and 20 AFEC) were subjected to a more-extensive characterization which included serogrouping, antimicrobial susceptibility analysis, screening for seven intestinal E. coli virulence genes (stx1, stx2, eae, espP, KatP, hlyA, and fliCh7), multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and in vivo virulence testing. More than 90% of the total APEC examined possessed iroN, ompT, hlyF, iss, and iutA, indicating that Egyptian APECs, like their counterparts from the United States, harbor plasmid pathogenicity islands (PAIs). The majority of APEC and AFEC were of phylogenetic groups A, B1, and D. For the 50-isolate subgroup, more than 70% of APEC and 80% ofAFEC were multidrug resistant. Among the subgroup of APEC, MLST analysis identified 11 sequence types (ST) while seven STs were found among AFEC. Based on PFGE, the genetic relatedness of APEC and AFEC ranged from 50%-100% and clustered into four primary groups at 50% similarity. Two of the eight APEC strains tested in chickens were able to induce 25% mortality in 1-day-old chicks. APECs were distinguished from AFECs and environmental E. coli by their content of plasmid PAI genes, whereas APEC isolated from colisepticemia and AFEC were not distinguishable based on their antimicrobial resistance patterns, as both groups were multidrug resistant. Avian E. coli strains from broiler flocks in Egypt show similar sequence types to E. coli associated with human infection.

  4. Characterization of Multiple-Antimicrobial-Resistant Escherichia coli Isolates from Diseased Chickens and Swine in China

    PubMed Central

    Yang, Hanchun; Chen, Sheng; White, David G.; Zhao, Shaohua; McDermott, Patrick; Walker, Robert; Meng, Jianghong

    2004-01-01

    Escherichia coli isolates from diseased piglets (n = 89) and chickens (n = 71) in China were characterized for O serogroups, virulence genes, antimicrobial susceptibility, class 1 integrons, and mechanisms of fluoroquinolone resistance. O78 was the most common serogroup identified (63%) among the chicken E. coli isolates. Most isolates were PCR positive for the increased serum survival gene (iss; 97%) and the temperature-sensitive hemagglutinin gene (tsh; 93%). The O serogroups of swine E. coli were not those typically associated with pathogenic strains, nor did they posses common characteristic virulence factors. Twenty-three serogroups were identified among the swine isolates; however, 38% were O nontypeable. Overall, isolates displayed resistance to nalidixic acid (100%), tetracycline (98%), sulfamethoxazole (84%), ampicillin (79%), streptomycin (77%), and trimethoprim-sulfamethoxazole (76%). Among the fluoroquinolones, resistance ranged between 64% to levofloxacin, 79% to ciprofloxacin, and 95% to difloxacin. DNA sequencing of gyrA, gyrB, parC, and parE quinolone resistance-determining regions of 39 nalidixic acid-resistant E. coli isolates revealed that a single gyrA mutation was found in all of the isolates; mutations in parC together with double gyrA mutations conferred high-level resistance to fluoroquinolones (ciprofloxacin MIC, ≥8 μg/ml). Class 1 integrons were identified in 17 (19%) isolates from swine and 42 (47%) from chickens. The majority of integrons possessed genes conferring resistance to streptomycin and trimethoprim. These findings suggest that multiple-antimicrobial-resistant E. coli isolates, including fluoroquinolone-resistant variants, are commonly present among diseased swine and chickens in China, and they also suggest the need for the introduction of surveillance programs in China to monitor antimicrobial resistance in pathogenic bacteria that can be potentially transmitted to humans from food animals. PMID:15297487

  5. A study on association of virulence determinants of verotoxic Escherichia coli isolated from cattle calves

    PubMed Central

    Parul, Singh; Bist, Basanti; Sharma, Barkha; Jain, Udit; Yadav, Janardan K.

    2016-01-01

    Aim: The present study was conducted to find the association among virulence determinants of verotoxic Escherichia coli (VTEC) isolated from cattle calf feces. Materials and Methods: A total of 216 cattle calf fecal samples were collected aseptically and processed under required conditions for the isolation of E. coli. The isolates were further subjected to multiplex polymerase chain reaction (mPCR) for the detection of virulent genes. All the VTEC isolates were serotyped at the Central Research Institute, Kasauli, Himachal Pradesh. The VTEC isolates were observed for the enterohemolysin production on washed sheep blood agar (wSBA). Results: A total of 177 presumptive E. coli were isolated from 216 calf fecal samples revealing an overall prevalence of E. coli to be 81.94%. A total of 32 (14.81%) isolates were detected as VTEC through mPCR. The prevalence of verotoxin genes vt1, vt2, and combination of vt1+vt2 in the VTEC isolates was found to be 12 (37.5%), 14 (43.75%), and 6 (18.75%), respectively. Other virulent genes eaeA and hlyA were found in 6 and 11 VTEC strains with prevalence values of 18.75% and 34.37%, respectively. A total of 13 different O serogroups were revealed in serotyping of 32 VTEC isolates. Out of 32 VTEC strains, only 26 (81.25%) were enterohemolytic on wSBA as they produced the characteristic small, turbid zone of hemolysis around the streaking line. Although enterohemolysin production has been attributed to the presence of hlyA gene, only 11 of 26 enterohemolysin producing VTEC were found to be harboring the hlyA gene (11/26) 42.03%. Conclusion: The present study concludes that there might be an association between the presence of verotoxin genes and enterohemolysin production in VTEC group of E. coli. PMID:27651684

  6. Identification of the Multi-Resistance Gene cfr in Escherichia coli Isolates of Animal Origin

    PubMed Central

    Ma, Jun; Li, Liang; Fang, Liang-Xing; Zhang, Qijing; Liu, Ya-Hong; Liao, Xiao-Ping

    2014-01-01

    Previous study indicated that the multi-resistance gene cfr was mainly found in gram-positive bacteria, such as Staphylococcus and Enterococcus, and was sporadically detected in Escherichia coli. Little is known about the prevalence and transmission mechanism of cfr in E. coli. In this study, the presence of cfr in E. coli isolates collected during 2010–2012 from food-producing animals in Guangdong Province of China was investigated, and the cfr-positive E. coli isolates were characterized by PFGE, plasmid profiling, and genetic environment analysis. Of the 839 E. coli isolates, 10 isolates from pig were cfr positive. All the cfr-positive isolates presented a multi-resistance phenotype and were genetically divergent as determined by PFGE. In 8 out of the 10 strains, the cfr gene was located on plasmids of ∼30 kb. Restriction digestion of the plasmids with EcoRI and sequence hybridization with a cfr-specific probe revealed that the cfr-harboring fragments ranged from 6 to 23 kb and a ∼18 kb cfr-carrying fragment was common for the plasmids that were ∼30 kb. Four different genetic environments of cfr were detected, in which cfr is flanked by two identical copies of IS26, which may loop out the intervening sequence through homologous recombination. Among the 8 plasmids of ∼30 kb, 7 plasmids shared the same genetic environment. These results demonstrate plasmid-carried cfr in E. coli and suggest that transposition and homologous recombination mediated by IS26 might have played a rule in the transfer of the cfr gene in E. coli. PMID:25036029

  7. Cephalosporin resistance mechanisms in Escherichia coli isolated from raw chicken imported into the UK.

    PubMed

    Dhanji, Hiran; Murphy, Niamh M; Doumith, Michel; Durmus, Sema; Lee, Susanne Surman; Hope, Russell; Woodford, Neil; Livermore, David M

    2010-12-01

    We characterized mechanisms of resistance to oxyimino-cephalosporins in Escherichia coli isolated from raw chicken meat imported into the UK from South America, to ascertain whether this foodstuff contributes to the dissemination in the UK of extended-spectrum β-lactamase (ESBL)-producing E. coli belonging to the international uropathogenic ST131 clone. Sampling and collection of imported raw chicken meat was performed in accordance with regulatory guidelines by the London Port Health Authority at Tilbury. E. coli strains producing ESBLs were isolated based on growth within the zones of cefpodoxime (10 μg) discs. MICs were determined by agar dilution and interpreted using BSAC/EUCAST breakpoints. PCR was used to determine the phylogenetic groups of E. coli, to detect ESBL genes and to determine the incompatibility groups of plasmids encoding CTX-M enzymes. The molecular environments surrounding bla(CTX-M) were determined by DNA sequencing and PCR mapping. A total of 141 oxyimino-cephalosporin-resistant E. coli were isolated from 62 of 210 batches of imported raw chicken sampled. Thirty percent of these isolates produced group 2 CTX-M ESBLs, 27% produced group 8 CTX-M ESBLs, 42% produced CMY-type AmpC enzymes and 1% produced a group 2 CTX-M along with a CMY enzyme; none produced CTX-M-15 ESBL and none belonged to the ST131 clone. In contrast to human clinical ESBL E. coli, >90% of isolates were susceptible to ciprofloxacin and 74% to all aminoglycosides. Raw chicken imported into the UK from South America commonly carries ESBL-producing E. coli, but is not a significant source for the ST131 clone or for the CTX-M-15 ESBL.

  8. 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.

  9. Exploring the contribution of efflux on the resistance to fluoroquinolones in clinical isolates of Escherichia coli.

    PubMed

    Paltansing, Sunita; Tengeler, Anouk C; Kraakman, Margriet E M; Claas, Eric C J; Bernards, Alexandra T

    2013-12-01

    Resistance to ciprofloxacin in Escherichia coli is increasing parallel to increased use of fluoroquinolones both in The Netherlands and in other European countries. The objective was to investigate the contribution of active efflux and expression of outer membrane proteins (OMPs) in a collection of clinical E. coli isolates collected at a clinical microbiology department in a Dutch hospital. Forty-seven E. coli isolates a wide range of ciprofloxacin minimum inhibitory concentrations and known mutations in the quinolone resistance determining region were included. A fluorometric determination of bisbenzimide efflux was used two different efflux pump inhibitors and compared to quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for the expression levels of acrA, acrB, tolC, yhiV, and mdfA efflux pump genes and the OMPs ompF and ompX. Six isolates (12.7%) showed increased efflux. Although in 35 isolates (76%), overexpression of ≥1 efflux pump genes using qRT-PCR was present. Only the combined overexpression of acrAB-TolC and mdfA correlated with the phenotypic efflux assay using glucose/carbonyl cyanide m-chlorophenylhydrazone with glucose. Thus, efflux was involved in ciprofloxacin resistance in a limited number of E. coli isolates collected at a clinical microbiology department in a Dutch hospital complementing other resistance mechanisms.

  10. Antibiotic and Disinfectant Resistance of Escherichia coli Isolated from Retail Meats in Sichuan, China.

    PubMed

    Zhang, Anyun; He, Xuemei; Meng, Yue; Guo, Lijuan; Long, Mei; Yu, Hua; Li, Bei; Fan, Liangqian; Liu, Shuliang; Wang, Hongning; Zou, Likou

    2016-01-01

    To demonstrate the resistance of antibiotics and disinfectants to Escherichia coli isolates, 255 E. coli strains were isolated from 328 retail meat samples in this study. Susceptibility testing results showed that 85.5% isolates were resistant to at least one antibiotic drug. The E. coli isolates showed the highest resistance to sulfamethoxazole (61.6%), followed by tetracycline (61.2%), ampicillin (48.2%), cefalotin (29.8%), and kanamycin (22.4%). The minimum inhibitory concentrations of the disinfectants cetyltrimethylammonium bromide, N,N-didecyl-N,N-dimethylammonium chloride, cetyltrimethylammonium bromide, and cetylpyridinium chloride for E. coli were 16-1,024, 4-1,024, 16-512, and 8-512 mg/L, respectively. The emrE, ydgE/ydgF, mdfA, and sugE(c) genes were commonly present (53.7-83.1%), but the qac and sugE(p) genes were less prevalent (0.0-14.9%). The qac genes were highly associated with antimicrobial resistance. Conjugative transfer experiment indicated that the disinfectant resistance genes, qacF, sugE(p), and qacEΔ1, were located on conjugative plasmids. Pulsed-field gel electrophoresis revealed that the antimicrobial-resistant isolates were associated with the sampling supermarkets or groceries. This study indicated that using quaternary ammonium compounds to decontaminate food processing environments may be ineffective and even provide a selective pressure for strains with acquired resistance to other antimicrobials.

  11. Molecular classification and drug resistance analysis of Escherichia coli isolated from poultry in China

    PubMed Central

    Gai, Wenyan; Wang, Junwei; Wang, Juan; Cui, Zhigang; Qu, Zhina; Cui, Jinghua; Du, Xiaoli; Huang, Xiumei; Zhao, Jianmei

    2015-01-01

    We aimed to understand the distribution of Escherichia coli in poultry and to reveal the virulence factors, the drug resistance and molecular epidemic regularity and characteristics of isolate strains from 6 provinces in China and to complete the characteristics of E. coli for the risk assessment. A total of 87 E. coli isolates were analyzed with 7 virulence genes by PCR drug sensitivity test in 13 kinds of antimicrobial agents and analyzed with PFGE and MLST genotyping. The PFGE genotyping of 87 isolates yielded 75 PFGE type. MLST analysis of isolates identified the 39 STs, the 7 housekeeping genes had the different variation. The most prevalent virulence genes were iucD (74.7%), followed by iss (55.2%), Irp2 (43.7%), tsh (28.7%), cva (19.5%), papC (9.2%) and vat (8.1%). All isolates were resistant to two or three antimicrobial agents highly resistant to SXT, TE (85.06%), SF (83.91%), AM (66. 67%), to fluoroquinolones (ENR, 63.22%, NOR, 50.57%) and to GM (57.47%). E. coli strains resistant spectrum was wide gene was polymorphism the distribution had a certain timeliness and regional in part region of China. These were a solid foundation for the epidemiological investigation and traceability laid. PMID:25785064

  12. Replication of Colonic Crohn's Disease Mucosal Escherichia coli Isolates within Macrophages and Their Susceptibility to Antibiotics.

    PubMed

    Subramanian, Sreedhar; Roberts, Carol L; Hart, C Anthony; Martin, Helen M; Edwards, Steve W; Rhodes, Jonathan M; Campbell, Barry J

    2008-02-01

    There is increasing evidence that Escherichia coli organisms are important in Crohn's disease (CD) pathogenesis. In CD tissue they are found within macrophages, and the adherent-invasive CD ileal E. coli isolate LF82 can replicate inside macrophage phagolysosomes. This study investigates replication and antibiotic susceptibility of CD colonic E. coli isolates inside macrophages. Replication of CD colonic E. coli within J774-A1 murine macrophages and human monocyte-derived macrophages (HMDM) was assessed by culture and lysis after gentamicin killing of noninternalized bacteria and verified by electron microscopy (EM). All seven CD colonic isolates tested replicated within J774-A1 macrophages by 3 h (6.36-fold +/- 0.7-fold increase; n = 7 isolates) to a similar extent to CD ileal E. coli LF82 (6.8-fold +/- 0.8-fold) but significantly more than control patient isolates (5.2-fold +/- 0.25-fold; n = 6; P = 0.006) and E. coli K-12 (1.0-fold +/- 0.1-fold; P < 0.0001). Replication of CD E. coli HM605 within HMDM (3.9-fold +/- 0.7-fold) exceeded that for K-12 (1.4-fold +/- 0.2-fold; P = 0.03). EM showed replicating E. coli within macrophage vacuoles. Killing of HM605 within J774-A1 macrophages following a 3-h incubation with antibiotics at published peak serum concentrations (C(max)) was as follows: for ciprofloxacin, 99.5% +/- 0.2%; rifampin, 85.1% +/- 6.6%; tetracycline, 62.8% +/- 6.1%; clarithromycin, 62.1% +/- 5.6% (all P < 0.0001); sulfamethoxazole, 61.3% +/- 7.0% (P = 0.0007); trimethoprim, 56.3% +/- 3.4% (P < 0.0001); and azithromycin, 41.0% +/- 10.5% (P = 0.03). Ampicillin was not effective against intracellular E. coli. Triple antibiotic combinations were assessed at 10% C(max), with ciprofloxacin, tetracycline, and trimethoprim causing 97% +/- 0.0% killing versus 86% +/- 2.0% for ciprofloxacin alone. Colonic mucosa-associated E. coli, particularly CD isolates, replicate within macrophages. Clinical trials are indicated to assess the efficacy of a combination

  13. Isolation of atypical enteropathogenic and shiga toxin encoding Escherichia coli strains from poultry in Tehran, Iran

    PubMed Central

    Doregiraee, Fatemeh; Alebouyeh, Masoud; Nayeri Fasaei, Bahar; Charkhkar, Saeed; Tajedin, Elahe; Zali, Mohammad Reza

    2016-01-01

    Aim: The purpose of this study was to investigate the prevalence of enteropathogenic Escherichia coli (EPEC) and shiga toxin producing E. coli (STEC) strains in healthy broilers in Iran. Background: STEC and EPEC strains as diarrheagenic E. coli are among the most prevalent causative agents in acute diarrhea. Domestic animals, mainly cattle and sheep, have been implicated as the principal reservoirs of these pathotypes; however their prevalence among the broilers is varied among different countries. Patients and methods: A total of 500 cloacal swab samples from broilers of five different poultry houses (A-E) were collected to investigate the presence of stx1, stx2, hly, eae, and bfp virulence genes among the E. coli isolates by polymerase chain reaction. The shiga toxin encoding strains were evaluated serologically to detect their interaction with a commercial antiserum against O157 antigen. Results: Out of the 500 collected samples, 444 E. coli strains were isolated. Three strains (0.67%) presented at least one of the studied virulence genes (stx2, hly and eae), two strains were identified as STEC (stx2+, O157:nonH7) and one as an atypical EPEC strains (eae+ bfp-). Conclusion: The study established the presence of STEC and atypical EPEC in healthy broilers in Iran. Poultry might serve as vectors for transmission of pathogenic E. coli to human populations. PMID:26744615

  14. Virulence and antimicrobial resistance profiles among Escherichia coli strains isolated from human and animal wastewater.

    PubMed

    Sabaté, Montserrat; Prats, Guillem; Moreno, Eva; Ballesté, Elisenda; Blanch, Anicet R; Andreu, Antonia

    2008-05-01

    To gain insight into whether Escherichia coli isolated from humans and resistant to some common antimicrobial agents are derived from animals, 85 E. coli strains were selected by ERIC-PCR from human and animal wastewater samples. Phylogroup, pathogenicity islands (PAIs), resistance to quinolones, fluoroquinolones and presence of extended-spectrum beta-lactamases (ESBLs) were analyzed. Among the total, 55% were resistant to nalidixic acid and 38% to ciprofloxacin; 12% produced ESBLs. Chicken-derived strains were associated with quinolone and fluoroquinolone resistance and presence of ESBLs, while human strains were associated with susceptibility. Group B2 E. coli strains were associated with human origin, susceptibility to fluoroquinolones and presence of PAIs, whereas groups A, B1 and D showed a low virulence profile and a high level of antimicrobial resistance. In both human and animal wastewater, E. coli A, B1 and D were prevalent, and strains from both origins showed a similar virulence profile in each phylogroup. These findings led us to hypothesize that abusive antibiotic use in food animal production may promote the development of resistance among these intestinal E. coli phylogroups, which could later be transmitted to humans through the food supply. The low prevalence of E. coli group B2 in the animal gut may explain, at least in part, the absence of emergence of resistant B2 isolates.

  15. Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran

    PubMed Central

    Talebiyan, Reza; Kheradmand, Mehdi; Khamesipour, Faham; Rabiee-Faradonbeh, Mohammad

    2014-01-01

    Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances. PMID:25548716

  16. Multiple Antimicrobial Resistance of Escherichia coli Isolated from Chickens in Iran.

    PubMed

    Talebiyan, Reza; Kheradmand, Mehdi; Khamesipour, Faham; Rabiee-Faradonbeh, Mohammad

    2014-01-01

    Antimicrobial agents are used extremely in order to reduce the great losses caused by Escherichia coli infections in poultry industry. In this study, 318 pathogenic Escherichia coli (APEC) strains isolated from commercial broiler flocks with coli-septicemia were examined for antimicrobials of both veterinary and human significance by disc diffusion method. Multiple resistances to antimicrobial agents were observed in all the isolates. Resistance to the antibiotics was as follows: Tylosin (88.68%), Erythromycin (71.70%), Oxytetracycline (43.40%), Sulfadimethoxine-Trimethoprim (39.62%), Enrofloxacin (37.74%), Florfenicol (35.85%), Chlortetracycline (33.96%), Doxycycline (16.98%), Difloxacin (32.08%), Danofloxacin (28.30%), Chloramphenicol (20.75%), Ciprofloxacin (7.55%), and Gentamicin (5.66%). This study showed resistance against the antimicrobial agents that are commonly applied in poultry, although resistance against the antibiotics that are only applied in humans or less frequently used in poultry was significantly low. This study emphasizes on the occurrence of multiple drug resistant E. coli among diseased broiler chickens in Iran. The data revealed the relative risks of using antimicrobials in poultry industry. It also concluded that use of antibiotics must be limited in poultry farms in order to reduce the antibiotic resistances.

  17. 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.

  18. Genetic Features of MCR-1-Producing Colistin-Resistant Escherichia coli Isolates in South Africa

    PubMed Central

    Kieffer, Nicolas; Brink, Adrian; Coetze, Jennifer; Jayol, Aurélie; Nordmann, Patrice

    2016-01-01

    A series of colistin-resistant Escherichia coli clinical isolates was recovered from hospitalized and community patients in South Africa. Seven clonally unrelated isolates harbored the mcr-1 gene located on different plasmid backbones. Two distinct plasmids were fully sequenced, and identical 2,600-bp-long DNA sequences defining a mcr-1 cassette were identified. Promoter sequences responsible for the expression of mcr-1, deduced from the precise identification of the +1 transcription start site for mcr-1, were characterized. PMID:27161623

  19. Characterization of extraintestinal pathogenic Escherichia coli isolated from captive wild felids with bacteremia.

    PubMed

    Carvalho, Vania M; Osugui, Lika; Setzer, Ariela P; Lopez, Rodrigo P G; Pestana de Castro, Antonio F; Irino, Kinue; Catão-Dias, José L

    2012-09-01

    Diseases caused by extraintestinal pathogenic Escherichia coli (ExPEC) in wild felids are rarely reported. Although urinary tract infections are infrequently reported in domestic cats, such infections when present are commonly caused by ExPEC. The present work characterized ExPEC strains isolated from 2 adult felines, a snow leopard (Panthera uncia) and a black leopard (Panthera pardus melas), that died from secondary bacteremia associated with urinary tract infections. Isolates from both animals were classified into the B2 phylogenetic group and expressed virulence genotypes that allowed them to cause severe disease. In addition, strains from the black leopard showed multidrug resistance.

  20. Prevalence of Antimicrobial Resistance in Escherichia coli Strains Isolated from Fishery Workers

    PubMed Central

    Shin, Hyun-Ho; Cho, Seung-Hak

    2013-01-01

    Objectives: This study aimed to characterize the prevalence of antibiotic resistance in Escherichia coli isolates from the fecal samples of fishery workers who work in fish farms and often use antibiotics for the feeding fishes. Methods: Seventy-three E. coli strains isolated from the fecal samples of fishery workers and 180 isolates from a control group of restaurant workers were tested for antibiotic resistance by agar disk diffusion with 16 antimicrobial agents. Results: About 30% of isolates from each group showed antimicrobial resistance to ampicillin, and 60% of isolates from fishery workers and 41% from restaurant workers were resistant to tetracycline. The isolates showed higher resistance to cephalothin and cefoxitin than to other cephem antibiotics and to gentamicin than to other aminogycosides. Our data indicated that fecal E. coli isolates from fishery workers showed higher antibiotic resistance than those of non-fishery workers (restaurant workers), especially to cephalothin, tetracycline, and trimethoprim–sulfamethoxazole (p < 0.05). However, rates of multidrug resistance were similar among the fishery workers and restaurant workers. Conclusion: Frequent use of antibiotics may cause increased antibiotic resistance in the human microbiome. PMID:24159534

  1. Antimicrobial resistance of Escherichia coli isolated from chickens with colibacillosis in and around Harare, Zimbabwe.

    PubMed

    Saidi, Bamusi; Mafirakureva, Prettimore; Mbanga, Joshua

    2013-03-01

    Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC), can lead to great economic losses in the poultry industry. The aim of this study was to determine the prevalence of antibiotic resistance and antibiotic resistance patterns in APEC in Zimbabwe. From 503 chickens diagnosed with colibacillosis, 103 E. coli isolates were obtained. Isolation and identification of E. coli were carried out using microscopy and biochemical tests. The disc diffusion method was used to determine antibiotic susceptibility of the isolates to 8 commercial antibiotics. Many isolates exhibited resistance to more than one antibiotic. Antibiogram profiles indicated maximum resistance to tetracycline (100%), bacitracin (100%), and cloxacillin (100%) and a high prevalence of resistance to ampicillin (94.1%). However; there were high prevalences of sensitivity to ciprofloxacin (100%) and gentamycin (97.1%). The isolates showed moderate rates of sensitivity to chloramphenicol and neomycin. All isolates in this study showed multidrug resistance because they were all resistant to 3 or more antibiotics. Seven multidrug resistance patterns were observed. The most common pattern (resistance to ampicillin, bacitracin, cloxacillin, and tetracycline) was exhibited by 30 isolates. Our findings show that there is emerging drug resistance in APEC associated with colibacillosis in Zimbabwe. The observed high level of multidrug resistance could hamper the treatment of colibacillosis in Zimbabwe.

  2. An enzyme-linked immunosorbent assay-based isolation procedure for verotoxigenic Escherichia coli.

    PubMed Central

    Milley, D G; Sekla, L H

    1993-01-01

    A colony enzyme-linked immunosorbent assay using the hydrophobic grid membrane filter format was developed for the isolation of verotoxigenic Escherichia coli from human and food samples. The method utilizes monoclonal antibodies directed against the verotoxins and is sensitive to all verotoxin 1- and/or 2-producing serotypes. E. coli that produced a minimum of 2 x 10(2) and 2 x 10(3) 50% cytotoxic doses per ml of verotoxins 1 and 2, respectively, were detectable. In a method comparison using human stool specimens, this procedure isolated 29% more E. coli O157 than did the standard sorbitol-MacConkey agar procedure, with no false-positive reactions. When applied to meat, 11 of 20 samples positive for verotoxin by polymyxin extraction yielded verotoxigenic E. coli of a variety of serotypes including O157:H7. Four false positives were noted. This procedure provides a sensitive means for the isolation of verotoxigenic E. coli and should facilitate recovery of those serotypes that are otherwise indistinguishable from nonpathogenic strains. PMID:8285713

  3. Multi-drug-resistant enterotoxigenic and enterohemorrhagic Escherichia coli isolated from children with diarrhea.

    PubMed

    Zeighami, Habib; Haghi, Fakhri; Hajiahmadi, Fahimeh; Kashefiyeh, Mehdi; Memariani, Mojtaba

    2015-06-01

    Multi-drug-resistant (MDR) diarrheagenic Escherichia coli (DEC) has rapidly spread worldwide and represents the most serious threat to the management of diarrhea in developing countries. During the period from March 2011 to January 2012, a total of 450 stool samples of diarrheal children aged 0-60 months were studied. In order to detect enterotoxigenic E. coli (ETEC) and enterohemorrhagic E. coli (EHEC) simultaneously, a mixture of four primer pairs specific for eltB, estA, vt1, and vt2 genes was used in a multiplex PCR. Antimicrobial susceptibility testing was performed as the Clinical and Laboratory Standards Institute (CLSI) guidelines. A total of 140 (31·1%) DEC were isolated from 450 stool samples. Diarrheagenic E. coli exhibited high-level resistance to aztreonam (80·7%), amoxicillin (74·4%), and tetracycline (69·3%). Also, 86·4% of E. coli isolates were resistant to at least three different classes of antimicrobial agents and considered as MDR. The frequency of ETEC and EHEC pathotypes was 46·4 and 12·1%, respectively and all of these isolates were MDR. In conclusion, MDR ETEC continues to be an important agent associated with diarrhea in children from Tabriz, Iran.

  4. 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 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

  5. 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

  6. Genetic Diversity of Escherichia coli Isolated from Urban Rivers and Beach Water

    PubMed Central

    McLellan, Sandra L.

    2004-01-01

    Repetitive element anchored PCR was used to evaluate the genetic profiles of Escherichia coli isolated from surface water contaminated with urban stormwater, sanitary sewage, and gull feces to determine if strains found in environmental samples reflect the strain composition of E. coli obtained from host sources. Overall, there was less diversity in isolates collected from river and beach sites than with isolates obtained from human and nonhuman sources. Unique strain types comprised 28.8, 29.2, and 15.0% of the isolate data sets recovered from stormwater, river water, and beach water, respectively. In contrast, 50.4% of gull isolates and 41.2% of sewage isolates were unique strain types. River water, which is expected to contain E. coli strains from many diffuse sources of nonpoint source pollution, contained strains most closely associated with other river water isolates that were collected at different sites or on different days. However, river sites impacted by sewage discharge had approximately 20% more strains similar to sewage isolates than did sites impacted by stormwater alone. Beach sites with known gull fecal contamination contained E. coli most similar to other beach isolates rather than gull isolates collected at these same sites, indicating underrepresentation of possible gull strains. These results suggest large numbers of strains are needed to represent contributing host sources within a geographical location. Additionally, environmental survival may influence the composition of strains that can be recovered from contaminated waters. Understanding the ecology of indicator bacteria is important when interpreting fecal pollution assessments and developing source detection methodology. PMID:15294799

  7. Silver Resistance Genes Are Overrepresented among Escherichia coli Isolates with CTX-M Production

    PubMed Central

    Edquist, Petra; Sandegren, Linus; Adler, Marlen; Tängdén, Thomas; Drobni, Mirva; Olsen, Björn; Melhus, Åsa

    2014-01-01

    Members of the Enterobacteriaceae with extended-spectrum beta-lactamases (ESBLs) of the CTX-M type have disseminated rapidly in recent years and have become a threat to public health. In parallel with the CTX-M type expansion, the consumption and widespread use of silver-containing products has increased. To determine the carriage rates of silver resistance genes in different Escherichia coli populations, the presence of three silver resistance genes (silE, silP, and silS) and genes encoding CTX-M-, TEM-, and SHV-type enzymes were explored in E. coli isolates of human (n = 105) and avian (n = 111) origin. The antibiotic profiles were also determined. Isolates harboring CTX-M genes were further characterized, and phenotypic silver resistance was examined. The silE gene was present in 13 of the isolates. All of them were of human origin. Eleven of these isolates harbored ESBLs of the CTX-M type (P = 0.007), and eight of them were typed as CTX-M-15 and three as CTX-M-14. None of the silE-positive isolates was related to the O25b-ST131 clone, but 10 out of 13 belonged to the ST10 or ST58 complexes. Phenotypic silver resistance (silver nitrate MIC > 512 mg/liter) was observed after silver exposure in 12 of them, and a concomitant reduced susceptibility to piperacillin-tazobactam developed in three. In conclusion, 12% of the human E. coli isolates but none of the avian isolates harbored silver resistance genes. This indicates another route for or level of silver exposure for humans than that caused by common environmental contamination. Since silE-positive isolates were significantly more often found in CTX-M-positive isolates, it is possible that silver may exert a selective pressure on CTX-M-producing E. coli isolates. PMID:25128339

  8. Silver resistance genes are overrepresented among Escherichia coli isolates with CTX-M production.

    PubMed

    Sütterlin, Susanne; Edquist, Petra; Sandegren, Linus; Adler, Marlen; Tängdén, Thomas; Drobni, Mirva; Olsen, Björn; Melhus, Asa

    2014-11-01

    Members of the Enterobacteriaceae with extended-spectrum beta-lactamases (ESBLs) of the CTX-M type have disseminated rapidly in recent years and have become a threat to public health. In parallel with the CTX-M type expansion, the consumption and widespread use of silver-containing products has increased. To determine the carriage rates of silver resistance genes in different Escherichia coli populations, the presence of three silver resistance genes (silE, silP, and silS) and genes encoding CTX-M-, TEM-, and SHV-type enzymes were explored in E. coli isolates of human (n = 105) and avian (n = 111) origin. The antibiotic profiles were also determined. Isolates harboring CTX-M genes were further characterized, and phenotypic silver resistance was examined. The silE gene was present in 13 of the isolates. All of them were of human origin. Eleven of these isolates harbored ESBLs of the CTX-M type (P = 0.007), and eight of them were typed as CTX-M-15 and three as CTX-M-14. None of the silE-positive isolates was related to the O25b-ST131 clone, but 10 out of 13 belonged to the ST10 or ST58 complexes. Phenotypic silver resistance (silver nitrate MIC > 512 mg/liter) was observed after silver exposure in 12 of them, and a concomitant reduced susceptibility to piperacillin-tazobactam developed in three. In conclusion, 12% of the human E. coli isolates but none of the avian isolates harbored silver resistance genes. This indicates another route for or level of silver exposure for humans than that caused by common environmental contamination. Since silE-positive isolates were significantly more often found in CTX-M-positive isolates, it is possible that silver may exert a selective pressure on CTX-M-producing E. coli isolates.

  9. Characterization of Escherichia coli O157:H7 and other Shiga toxin-producing E. coli serotypes isolated from sheep.

    PubMed Central

    Kudva, I T; Hatfield, P G; Hovde, C J

    1997-01-01

    The isolation and characterization of Escherichia coli O157:H7 and non-O157 Shiga toxin-producing E. coli (STEC) strains from sheep are described. One flock 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 sheep 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 pulsed-field gel electrophoresis (PFGE) of chromosomal DNA and toxin gene restriction fragment length polymorphism (RFLP) analysis. Ten PFGE patterns and five RFLP patterns, identified among the isolates, showed that multiple E. coli O157:H7 strains were isolated from one flock, that a single animal simultaneously shed multiple E. coli O157:H7 strains, and that the strains shed by individuals changed over time. E. coli O157:H7 was isolated only by selective enrichment culture off 10 g of ovine feces. In contrast, strains of eight STEC serotypes other than O157:H7 were cultured from feces of sheep from a separate flock without enrichment. The predominant non-O157 STEC serotype found was O91:NM (NM indicates nonmotile), and others included O128:NM, O88:NM, O6:H49, and O5:NM. Irrespective of serotype, 98% of the ovine STEC isolates possessed various combinations of the virulence-associated genes for Shiga toxin(s) and the attaching-and-effacing lesion (stx1, stx2, and eae), suggesting their potential for human pathogenicity. The most common toxin-eae genotype was positive for stx1, stx2, and eae. A Vero cell cytotoxicity assay demonstrated that 90% of the representative STEC isolates tested expressed the toxin gene. The report demonstrates that sheep transiently shed a variety of STEC strains, including E. coli O157:H7, that have potential as human pathogens. PMID:9157149

  10. 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.

  11. Isolation and characterization of antisuppressor mutations in Escherichia coli.

    PubMed Central

    Sullivan, M A; Bock, R M

    1985-01-01

    Nonsense mutations in lacI have been shown to be useful as indicators of the efficiency of nonsense suppression. From strains containing supE and a lacI nonsense mutation, selection for LacI- mutants has resulted in the isolation of four antisuppressor mutations. Tn10 insertions linked to these mutations were isolated and used to group the four mutations into three loci. The asuA1 and asuA2 mutations are linked to trp, reduce suppression by supE approximately twofold, and affect a variety of suppressors. The asuB3 mutation was mapped by P1 cotransduction to rpsL but does not confer resistance to streptomycin. The asuC4 mutation reduced suppression by supE by 95% and was shown biochemically to result in the loss of two pseudouridine modifications from the 3' side of the anticodon stem and loop of tRNA2Gln. This mutation is linked to purF, suggesting that it is a new allele of hisT. Images PMID:3918006

  12. Phenotypic and Genotypic Characterization of Escherichia coli Isolated from Untreated Surface Waters

    PubMed Central

    Janezic, Kristopher J; Ferry, Blake; Hendricks, Eric W; Janiga, Brian A; Johnson, Tiffany; Murphy, Samantha; Roberts, Morgan E; Scott, Sarah M; Theisen, Alexandra N; Hung, Kai F; Daniel, Steven L

    2013-01-01

    A common member of the intestinal microbiota in humans and animals is Escherichia coli. Based on the presence of virulence factors, E. coli can be potentially pathogenic. The focus of this study was to isolate E. coli from untreated surface waters (37 sites) in Illinois and Missouri and determine phenotypic and genotypic diversity among isolates. Water samples positive for fecal coliforms based on the Colisure® test were streaked directly onto Eosin Methylene Blue (EMB) agar (37°C) or transferred to EC broth (44.5°C). EC broth cultures producing gas were then streaked onto EMB agar. Forty-five isolates were identified as E. coli using API 20E and Enterotube II identification systems, and some phenotypic variation was observed in metabolism and fermentation. Antibiotic susceptibility of each isolate was also determined using the Kirby-Bauer Method. Differential responses to 10 antimicrobial agents were seen with 7, 16, 2, and 9 of the isolates resistant to ampicillin, cephalothin, tetracycline, and triple sulfonamide, respectively. All of the isolates were susceptible or intermediate to amoxicillin, ciprofloxacin, polymyxin B, gentamicin, imipenem, and nalidixic acid. Genotypic variation was assessed through multiplex Polymerase Chain Reaction for four virulence genes (stx1 and stx2 [shiga toxin], eaeA [intimin]; and hlyA [enterohemolysin]) and one housekeeping gene (uidA [β-D-glucuronidase]). Genotypic variation was observed with two of the isolates possessing the virulence gene (eaeA) for intimin. These findings increase our understanding of the diversity of E. coli in the environment which will ultimately help in the assessment of this organism and its role in public health. PMID:23539437

  13. Clonal and pathotypic analysis of archetypal Escherichia coli cystitis isolate NU14.

    PubMed

    Johnson, J R; Weissman, S J; Stell, A L; Trintchina, E; Dykhuizen, D E; Sokurenko, E V

    2001-12-15

    Escherichia coli NU14, a cystitis isolate used to study the pathogenesis of cystitis and to develop a FimH (type 1 fimbrial adhesin) vaccine, was assessed for extended virulence genotype, phylogenetic background, and FimH sequence and binding phenotype(s). NU14 exhibited the same virulence genotype and was derived from the same (meningitis- and cystitis-associated) subclone of E. coli O18:K1:H7 as the archetypal neonatal bacterial meningitis (NBM) isolate RS218. NU14 also displayed the same Ser62Ala FimH polymorphism as did NBM isolates RS218 and IHE3034-conferring both collagen binding and a distinct monomannose binding capability (which characterizes uropathogenic but not commensal E. coli and dramatically increases adherence to uroepithelial cells). These findings establish that strain NU14 exhibits numerous urovirulence-associated traits and derives from the single most prevalent clonal group in acute cystitis. They provide further evidence of clonal and pathotypic similarities between cystitis and NBM isolates of E. coli O18:K1:H7.

  14. Antimicrobial Resistance of Escherichia coli O157 Isolated from Humans, Cattle, Swine, and Food

    PubMed Central

    Schroeder, Carl M.; Zhao, Cuiwei; DebRoy, Chitrita; Torcolini, Jocelyn; Zhao, Shaohua; White, David G.; Wagner, David D.; McDermott, Patrick F.; Walker, Robert D.; Meng, Jianghong

    2002-01-01

    A total of 361 Escherichia coli O157 isolates, recovered from humans, cattle, swine, and food during the years 1985 to 2000, were examined to better understand the prevalence of antimicrobial resistance among these organisms. Based on broth microdilution results, 220 (61%) of the isolates were susceptible to all 13 antimicrobials tested. Ninety-nine (27%) of the isolates, however, were resistant to tetracycline, 93 (26%) were resistant to sulfamethoxazole, 61 (17%) were resistant to cephalothin, and 48 (13%) were resistant to ampicillin. Highest frequencies of resistance occurred among swine isolates (n = 70), where 52 (74%) were resistant to sulfamethoxazole, 50 (71%) were resistant to tetracycline, 38 (54%) were resistant to cephalothin, and 17 (24%) were resistant to ampicillin. Based on the presence of Shiga toxin genes as determined by PCR, 210 (58%) of the isolates were identified as Shiga toxin-producing E. coli (STEC). Among these, resistance was generally low, yet 21 (10%) were resistant to sulfamethoxazole and 19 (9%) were resistant to tetracycline. Based on latex agglutination, 189 (52%) of the isolates were identified as E. coli O157:H7, among which 19 (10%) were resistant to sulfamethoxazole and 16 (8%) were resistant to tetracycline. The data suggest that selection pressure imposed by the use of tetracycline derivatives, sulfa drugs, cephalosporins, and penicillins, whether therapeutically in human and veterinary medicine or as prophylaxis in the animal production environment, is a key driving force in the selection of antimicrobial resistance in STEC and non-STEC O157. PMID:11823193

  15. Antimicrobial resistance in clinical Escherichia coli isolates from poultry and livestock, China.

    PubMed

    Yassin, Afrah Kamal; Gong, Jiansen; Kelly, Patrick; Lu, Guangwu; Guardabassi, Luca; Wei, Lanjing; Han, Xiangan; Qiu, Haixiang; Price, Stuart; Cheng, Darong; Wang, Chengming

    2017-01-01

    Poultry and livestock are the most important reservoirs for pathogenic Escherichia coli and use of antimicrobials in animal farming is considered the most important factor promoting the emergence, selection and dissemination of antimicrobial-resistant microorganisms. The aim of our study was to investigate antimicrobial resistance in E. coli isolated from food animals in Jiangsu, China. The disc diffusion method was used to determine susceptibility to 18 antimicrobial agents in 862 clinical isolates collected from chickens, ducks, pigs, and cows between 2004 and 2012. Overall, 94% of the isolates showed resistance to at least one drug with 83% being resistance to at least three different classes of antimicrobials. The isolates from the different species were most commonly resistant to tetracycline, nalidixic acid, sulfamethoxazole, trimethoprim/sulfamethoxazole and ampicillin, and showed increasing resistance to amikacin, aztreonam, ceftazidime, cefotaxime, chloramphenicol, ciprofloxacin. They were least resistant to amoxicillin/clavulanic acid (3.4%) and ertapenem (0.2%). MDR was most common in isolates from ducks (44/44, 100%), followed by chickens (568/644, 88.2%), pigs (93/113, 82.3%) and cows (13/61, 21.3%). Our finding that clinical E. coli isolates from poultry and livestock are commonly resistant to multiple antibiotics should alert public health and veterinary authorities to limit and rationalize antimicrobial use in China.

  16. Virulence genotypes of Escherichia coli canine isolates from pyometra, cystitis and fecal origin.

    PubMed

    Mateus, Luisa; Henriques, Sofia; Merino, Carolina; Pomba, Constança; Lopes da Costa, Luís; Silva, Elisabete

    2013-10-25

    Pyometra is the most common diestrual uterine disease of bitches. Escherichia coli is the most frequent bacterium isolated from the uterine content of pyometra uteri and it is associated with the most severe clinical signs, leading to endotoxemia and sepsis. In this study, canine E. coli isolates from pyometra (n=31), cystitis (n=23) and fecal (n=26) origin were compared regarding the prevalence of 23 potential virulence traits (15 virulence factor (VF) genes and 8 pathogenicity associated islands-PAIs), detected by PCR assays. Overall, there was a considerable overlap between pyometra, cystitis and fecal isolates regarding the phylogenetic grouping and virulence traits. Virulence traits more prevalent in pyometra than in cystitis and fecal isolates included two PAIs (PAI IV536 and PAI ICFT073) and three VF genes (sfa/focDE, fyuA and chuA). Regardless the isolates' origin, the average number of virulence traits per strain was higher in B2 than in the other phylogenetic groups (A, B1 and D). The prevalence of phylogenetic group B2 was significantly higher in pyometra (94%) than in cystitis (48%) and fecal (39%) isolates. In conclusion, pyometra isolates have a high potential of virulence and a broad virulence genotype, although being similar to a subset of cystitis and fecal isolates. This leads to the suggestion that cystitis and fecal isolates may be able to induce pyometra in receptive hosts.

  17. Relatedness of Escherichia coli Strains with Different Susceptibility Phenotypes Isolated from Swine Feces during Ampicillin Treatment▿

    PubMed Central

    Bibbal, D.; Dupouy, V.; Prère, M. F.; Toutain, P. L.; Bousquet-Mélou, A.

    2009-01-01

    The aim of this study was to examine the dynamics of the development of resistance in fecal Escherichia coli populations during treatment with ampicillin for 7 days in pigs. Before treatment, only 6% of the isolates were ampicillin resistant, whereas more than 90% of the isolates were resistant after days 4 and 7 of treatment. Ampicillin-resistant E. coli isolates were mainly multiresistant, and 53% of the isolates from the treated pigs had one phenotype that included resistance to six antibiotics (ampicillin, chloramphenicol, sulfonamides, tetracycline, trimethoprim, and streptomycin) at day 7. Determination of the frequency of the four phylogenetic groups showed that there was a shift in the E. coli population in ampicillin-treated pigs; before treatment 75% of the isolates belonged to phylogroup B1, whereas at day 7 85% of the isolates belonged to phylogroup A. Pulsed-field gel electrophoresis (PFGE) typing revealed that ampicillin treatment selected ampicillin-resistant isolates with genotypes which were present before treatment. Comparison of antimicrobial phenotypes and PFGE genotypes showed that resistance traits were disseminated by vertical transmission through defined strains. One PFGE genotype, associated with the six-antibiotic-resistant phenotype and including a specific combination of resistance determinants, was predominant among the ampicillin-resistant strains before treatment and during treatment. These data indicate that ampicillin administration selected various ampicillin-resistant isolates that were present in the digestive tract before any treatment and that E. coli isolates belonging to one specific PFGE genotype encoding resistance to six antibiotics became the predominant strains as soon as ampicillin was present in the digestive tract. PMID:19270132

  18. 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.

  19. Virulence genes in bla(CTX-M) Escherichia coli isolates from chickens and humans.

    PubMed

    Randall, Luke; Wu, Guanghui; Phillips, Neil; Coldham, Nick; Mevius, Dik; Teale, Chris

    2012-08-01

    The aim of this study was to determine the presence of virulence genes in isolates of CTX-M Escherichia coli from diseased chickens, from healthy chickens and from urinary tract infections in people. Three CTX-M E. coli strains from three different instances of disease in poultry (two of which were E. coli related) were tested for bla(CTX-M) sequence type and replicon type. Additionally, they were tested for the presence of 56 virulence genes (encoding fimbriae, adhesins, toxins, microcins and iron acquisition genes) using a micro-array. Results were compared to the virulence genes present in isolates from 26 healthy chickens and from 10 people with urinary tract infections. All genes found in isolates from diseased birds, including the astA (heat stable toxin) and tsh (temperature sensitive haemagglutinin) genes which have previously been associated with colibacillosis in chickens, were also present in isolates from healthy birds. However, 6/10 of the virulence genes found were exclusive to isolates from humans. Genes exclusive to chicken isolates included ireA (sidephore receptor), lpfA (long polar fimbriae), mchF (microcin transporter protein) and tsh whilst genes exclusive to human isolates included ctdB (cytolethal distending toxin), nfaE (non-fimbrial adhesion), senB (plasmid encoded enterotoxin) and toxB (toxin B). The results support previous findings that CTX-M E. coli strains in chickens are generally different from those causing disease in humans, but genes such as astA and tsh in isolates from diseased birds with colisepticaemia were also present in isolates from healthy birds. Crown Copyright © 2011. Published by Elsevier India Pvt Ltd. All rights reserved.

  20. 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

  1. Recurrent Escherichia coli bacteremia.

    PubMed Central

    Maslow, J N; Mulligan, M E; Arbeit, R D

    1994-01-01

    Escherichia coli is the most common gram-negative organism associated with bacteremia. While recurrent E. coli urinary tract infections are well-described, recurrent E. coli bacteremia appears to be uncommon, with no episodes noted in multiple series of patients with gram-negative bacteremias. We report on 5 patients with recurrent bloodstream infections identified from a series of 163 patients with E. coli bacteremia. For each patient, the isolates from each episode were analyzed by pulsed-field gel electrophoresis (PFGE) and ribotyping and for the presence of E. coli virulence factors. For each of four patients, the index and recurrent episodes of bacteremia represented the same strain as defined by PFGE, and the strains were found to carry one or more virulence factors. The remaining patient, with two episodes of bloodstream infection separated by a 4-year interval, was infected with two isolates that did not carry any virulence factors and that were clonally related by ribotype analysis but differed by PFGE. All five patients had either a local host defense defect (three patients) or impaired systemic defenses (one patient) or both (one patient). Thus, recurrent E. coli bacteremia is likely to represent a multifactorial process that occurs in patients with impaired host defenses who are infected with virulent isolates. Images PMID:7910828

  2. Evaluation of the adhesive capacity of Escherichia coli isolates associated with avian cellulitis.

    PubMed

    Leclerc, Benoît; Fairbrother, John M; Boulianne, Martine; Messier, Serge

    2003-01-01

    It has been shown that Escherichia coli isolates from lesions of cellulitis belong to a limited number of clonal groups distinct from those of isolates found in the environment of these birds. In this study, different in vitro methods were used to evaluate adherence properties of E. coli isolates from cellulitis lesions and environments of high- and low-cellulitis prevalence broiler flocks. One hundred isolates were tested by hemagglutination. Adherence to frozen sections of chicken skin and binding to soluble fibronectin were examined for 40 of these 100 isolates by immunofluorescence and by immunocytofluorometry, respectively. Localization of bacterial adherence to skin tissues was confirmed by immunohistochemistry. It was demonstrated that O78:K80 isolates from cellulitis lesions adhered to skin sections to a much greater extent in deeper than in superficial tissue layers. A greater bacterial adherence following growth in TSB at 37 C was demonstrated for isolates from flocks with high prevalence of cellulitis than for isolates from flocks with low prevalence of cellulitis. MANOVA analysis results showed a significant difference between superficial and deep tissue layers only for one set of isolates from flocks with high prevalence of cellulitis. Hemagglutinating activity was variable among the O78:K80 isolates obtained from flocks with high prevalence of cellulitis. The results obtained for some O78:K80 isolates following growth in TSB suggest a role for type 1 fimbriae or F1 in adherence to skin sections. This was reinforced by the finding that adherence was inhibited by D-mannose. Poultry E. coli isolates that express F1 had no affinity for soluble fibronectin, although localization of the adherence in skin sections suggested a role for extracellular matrix components such as collagen and insoluble fibronectin.

  3. Antimicrobial resistance and resistance genes in Escherichia coli isolated from retail meat purchased in Alberta, Canada.

    PubMed

    Sheikh, Ali Ahmad; Checkley, Sylvia; Avery, Brent; Chalmers, Gabhan; Bohaychuk, Valerie; Boerlin, Patrick; Reid-Smith, Richard; Aslam, Mueen

    2012-07-01

    This study analyzed antimicrobial resistance (AMR) and resistance genes in generic Escherichia coli isolated from retail meat samples purchased (2007-2008) in Alberta, Canada, and determined potential associations between resistance phenotypes and resistance genes with relation to the meat types. A total of 422 E. coli isolates from retail chicken, turkey, beef, and pork meats were tested for antimicrobial susceptibility. Multiplex PCRs were used to detect major resistance genes for tetracyclines [tet(A), tet(B), tet(C)], sulfonamides (sul1, sul2, sul3), aminoglycosides (strA/B, aadA, aadB, aac(3)IV, aphA1, aphA2), and β-lactamase (bla(CMY-2), bla(TEM), bla(SHV), bla(PSE-1)). Resistance to ciprofloxacin was not found in any isolate. Overall resistances to clinically important antimicrobials amoxicillin-clavulanic acid (16.8% of isolates) and ceftriaxone (12.6% isolates) were observed. These resistances were observed more frequently (p<0.0001) in chicken-derived E. coli than those from the other meat types. Resistance to multiple antimicrobials (≥ 5) was found in more chicken derived E. coli (32%) than E. coli from other meat types. The β-lactamase genes of clinical importance, including bla(CMY-2) and bla(TEM), were found in about 18% of poultry-derived E. coli and in only 5% of ground beef. The bla(CMY-2) gene was more likely to be found in E. coli from chicken than turkey, beef, or pork meats. The tet(A) gene was associated with bla(CMY-2), whereas bla(CMY-2) and bla(TEM) genes were associated with strA/B genes. Resistance genes for tetracycline, sulfonamides, and aminoglycosides were associated with the phenotypic expression of resistance to unrelated classes of antimicrobials. These data suggest the prevalence of AMR and select resistance genes were higher in poultry-derived E. coli. The multiple associations found between AMR phenotypes and resistance genes suggest a complex nature of resistance in E. coli from retail meat, and hence the use of a single

  4. 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.

  5. 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

  6. Isolation of Shiga Toxin-Producing Escherichia coli from a South American Camelid (Lama guanicoe) with Diarrhea

    PubMed Central

    Mercado, E. C.; Rodríguez, S. M.; Elizondo, A. M.; Marcoppido, G.; Parreño, V.

    2004-01-01

    Shiga toxin-producing Escherichia coli belonging to serotype O26:H11 was isolated from a 2-month-old guanaco with severe watery diarrhea. E. coli colonies carried the stx1 and eae genes, showed localized adherence to HEp-2 cells, and produced enterohemolysin. A serological response to lipopolysaccharide O26 was observed at the onset of diarrhea. PMID:15472347

  7. Colistin-resistant Escherichia coli clinical isolate harbouring the mcr-1 gene in Ecuador.

    PubMed

    Ortega-Paredes, D; Barba, P; Zurita, J

    2016-10-01

    Colistin resistance mediated by the mcr-1 gene has been reported worldwide, but to date not from the Andean region, South America. We report the first clinical isolate of Escherichia coli harbouring the mcr-1 gene in Ecuador. The strain was isolated from peritoneal fluid from a 14-year-old male with acute appendicitis, and subjected to molecular analysis. The minimum inhibitory concentration of colistin for the strain was 8 mg/ml and it was susceptible to carbapenems but resistant to tigecycline. The strain harboured mcr-1 and bla CTX-M-55 genes and was of sequence type 609. The recognition of an apparently commensal strain of E. coli harbouring mcr-1 serves as an alert to the presence in the region of this recently described resistance mechanism to one of the last line of drugs available for the treatment of multi-resistant Gram-negative infections.

  8. Isolation and Characterization of Supercoiled Circular Deoxyribonucleic Acid from Beta-Hemolytic Strains of Escherichia coli

    PubMed Central

    Goebel, Werner; Schrempf, Hildgund

    1971-01-01

    Covalently closed circular deoxyribonucleic acid (DNA) molecules were isolated by cesium chloride centrifugation in the presence of ethidium bromide from a naturally occurring beta-hemolytic Escherichia coli strain (SC52). The open circular forms have contour lengths of 2.25 ± 0.1 μm, 24.0 ± 0.3 μm, and 29.5 ± 0.5 μm. The beta-hemolytic character of E. coli SC52 can be transferred by conjugation to a nonhemolytic recipient strain. Analysis of the supercoiled DNA of the hemolytic recipient demonstrated that the two large supercoiled DNA molecules of E. coli SC52 are transferred during this event, too. A beta-hemolytic laboratory E. coli strain and several of its derivatives have been shown to contain at least one circular DNA molecule, slightly larger in size than those isolated from E. coli SC52 and its conjugant. The possible significance of these DNA molecules for hemolysin production and transfer is discussed. Images PMID:4929855

  9. In Vitro Activities of Cephalosporins and Quinolones against Escherichia coli Strains Isolated from Diarrheic Dairy Calves

    PubMed Central

    Orden, José Antonio; Ruiz-Santa-Quiteria, José Antonio; García, Silvia; Cid, Dolores; de la Fuente, Ricardo

    1999-01-01

    The in vitro activities of several cephalosporins and quinolones against 195 strains of Escherichia coli isolated from dairy calves affected by neonatal diarrhea were determined. One hundred thirty-seven of these strains produced one or more potential virulence factors (F5, F41, F17, cytotoxic necrotizing factor, verotoxin, and the eae gene), but the remaining 58 strains did not produce any of these factors. From 11 to 18% of the E. coli strains were resistant to cephalothin, nalidixic acid, enoxacin, and enrofloxacin. However, cefuroxime, cefotaxime, and cefquinome were highly effective against the E. coli isolates tested. Some significant differences (P < 0.05) in resistance to quinolones between the strains producing potential virulence factors and nonfimbriated, nontoxigenic, eae-negative strains were found. Thus, eae-positive, necrotoxigenic, and verotoxigenic (except for nalidixic acid) E. coli strains were significantly more sensitive to nalidixic acid, enoxacin, and enrofloxacin than nonfimbriated, nontoxigenic, eae-negative strains. Moreover, eae-positive strains were significantly more sensitive to enoxacin and enrofloxacin than F5-positive strains. Thus, the results of this study suggest that the bovine E. coli strains that produce some potential virulence factors are more sensitive to quinolones than those that do not express these factors. PMID:10049259

  10. Virulence genes, antibiotic resistance and integrons in Escherichia coli strains isolated from synanthropic birds from Spain.

    PubMed

    Sacristán, C; Esperón, F; Herrera-León, S; Iglesias, I; Neves, E; Nogal, V; Muñoz, M J; de la Torre, A

    2014-01-01

    The aim of this study was to determine the presence of virulence genes and antibiotic resistance profiles in 164 Escherichia coli strains isolated from birds (feral pigeons, hybrid ducks, house sparrows and spotless starlings) inhabiting urban and rural environments. A total of eight atypical enteropathogenic E. coli strains were identified: one in a house sparrow, four in feral pigeons and three in spotless starlings. Antibiotic resistance was present in 32.9% (54) of E. coli strains. The dominant type of resistance was to tetracycline (21.3%), ampicillin (19.5%) and sulfamethoxazole (18.9%). Five isolates had class 1 integrons containing gene cassettes encoding for dihydrofolate reductase A (dfrA) and aminoglycoside adenyltransferase A (aadA), one in a feral pigeon and four in spotless starlings. To our knowledge, the present study constitutes the first detection of virulence genes from E. coli in spotless starlings and house sparrows, and is also the first identification worldwide of integrons containing antibiotic resistance gene cassettes in E. coli strains from spotless starlings and pigeons.

  11. Virulence gene profiles of avian pathogenic Escherichia coli isolated from chickens with colibacillosis in Bulawayo, Zimbabwe.

    PubMed

    Mbanga, Joshua; Nyararai, Yvonne O

    2015-04-07

    Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC), is one of the main causes of economic losses in the poultry industry worldwide. This study was carried out in order to determine the APEC-associated virulence genes contained by E. coli isolates causing colibacillosis in chickens. A total of 45 E. coli isolates were obtained from the diagnostics and research branch of the Central Veterinary Laboratories, Bulawayo, Zimbabwe. These isolates were obtained from chickens with confirmed cases of colibacillosis after postmortem examination. The presence of the iutA, hlyF, ompT, frz, sitD, fimH, kpsM, sitA, sopB, uvrY, pstB and vat genes were investigated by multiplex polymerase chain reaction (PCR) assay. Of the 45 isolates, 93% were positive for the presence of at least one virulence gene. The three most prevalent virulence genes were iutA (80%), fimH (33.3%) and hlyF (24.4%). The kpsM, pstB and ompT genes had the lowest prevalence, having been detected in only 2.2% of the isolates. All 12 virulence genes studied were detected in the 45 APEC isolates. Virulence gene profiles were constructed for each APEC isolate from the multiplex data. The APEC isolates were profiled as 62.2% fitting profile A, 31.1% profile B and 6.7% profile C. None of the isolates had more than seven virulence genes. Virulence profiles of Zimbabwean APEC isolates are different from those previously reported. Zimbabwean APEC isolates appear to be less pathogenic and may rely on environmental factors and stress in hosts to establish infection.

  12. 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

  13. Echinoderms from Azores islands: an unexpected source of antibiotic resistant Enterococcus spp. and Escherichia coli isolates.

    PubMed

    Marinho, Catarina; Silva, Nuno; Pombo, Sofia; Santos, Tiago; Monteiro, Ricardo; Gonçalves, Alexandre; Micael, Joana; Rodrigues, Pedro; Costa, Ana Cristina; Igrejas, Gilberto; Poeta, Patrícia

    2013-04-15

    The prevalence of antibiotic resistance and the implicated mechanisms of resistance were evaluated in Enterococcus spp. and Escherichia coli, isolated from a total of 250 faecal samples of echinoderms collected from Azorean waters (Portugal). A total of 144 enterococci (120 Enterococcus faecium, 14 E. hirae, 8 E. faecalis, 2 E. gallinarum) and 10 E. coli were recovered. High percentages of resistance in enterococci were found for erythromycin, ampicillin, tetracyclin and ciprofloxacin. The erm(A) or erm(B), tet(M) and/or tet(L), vat(D), aac(6')-aph(2″) and aph(3')-IIIa genes were found in isolates resistant to erythromycin, tetracycline, quinupristin/dalfopristin, high-level gentamicin and high-level kanamycin, respectively. Resistance in E. coli isolates was detected for streptomycin, amikacin, tetracycline and tobramycin. The aadA gene was found in streptomycin-resistant isolates and tet(A)+tet(B) genes in tetracycline-resistant isolates. The data recovered are essential to improve knowledge about the dissemination of resistant strains through marine ecosystems and the possible implications involved in transferring these resistances either to other animals or to humans.

  14. Antimicrobial Susceptibility of Escherichia coli Isolated from Fresh-Marketed Nile Tilapia (Oreochromis niloticus)

    PubMed Central

    Rocha, Rafael dos Santos; Leite, Lana Oliveira; de Sousa, Oscarina Viana; Vieira, Regine Helena Silva dos Fernandes

    2014-01-01

    The contamination of seafood by bacteria of fecal origin, especially Escherichia coli, is a widely documented sanitary problem. The objective of the present study was to isolate E. coli strains from the gills, muscle, and body surface of farmed Nile tilapias (Oreochromis niloticus) fresh-marketed in supermarkets in Fortaleza (Ceará, Brazil), to determine their susceptibility to antibiotics of different families (amikacin, gentamicin, imipenem, cephalothin, cefotaxime, ciprofloxacin, aztreonam, ampicillin, nalidixic acid, tetracycline, and sulfametoxazol-trimetoprim), and to determine the nature of resistance by plasmid curing. Forty-four strains (body surface = 25, gills = 15, muscle = 4) were isolated, all of which were susceptible to amikacin, aztreonam, cefotaxime, ciprofloxacin, gentamicin, and imipenem. Gill and body surface samples yielded 11 isolates resistant to ampicillin, tetracycline, and sulfametoxazol-trimetoprim, 4 of which of plasmidial nature. The multiple antibiotic resistance index was higher for strains isolated from body surface than from gills. The overall high antibiotic susceptibility of E. coli strains isolated from fresh-marketed tilapia was satisfactory, although the occasional finding of plasmidial resistance points to the need for close microbiological surveillance of the farming, handling, and marketing conditions of aquaculture products. PMID:24808957

  15. Virulence characteristics of Escherichia coli isolates obtained from broiler breeders with salpingitis.

    PubMed

    Monroy, Maria A R; Knöbl, Terezinha; Bottino, José A; Ferreira, Claudete S Astolfi; Ferreira, Antonio J Piantino

    2005-01-01

    Thirty isolates of Escherichia coli from broiler breeders with salpingitis were studied. Using the slide agglutination test, the isolates were found to belong to serogroups O1, O2, O5, O36, O45, O53 and O78. Pathogenicity for day-old chicks was determined by air sac inoculation and isolates were categorized as having high, intermediate or low virulence. Growth on iron starvation medium was observed together with aerobactin production. Based on the results of in vitro adherence tests, attachment to oviduct epithelium from old birds was found to be superior to that observed using corresponding material from young birds. DNA hybridization testing for type 1, P, and S fimbriae revealed predominant expression of type 1, correlating with mannose-sensitive hemagglutination using guinea-pig erythrocytes. In this study, P and S fimbriae were not considered to be important adherence factors. Study findings would suggest that, as far as salpingitis is concerned, type 1 fimbriae can play an important role in E. coli infection in breeders. An interesting result to emerge from the study was the observation that E. coli isolates were completely resistant to serum from young breeders, whereas they were completely sensitive using serum from older breeders. Based on serogroups involved, pathogenicity for day-old chicks and virulence indicators, the salpingitis isolates were similar to those from cases of chronic respiratory disease.

  16. Comparisons of infant Escherichia coli isolates link genomic profiles with adaptation to the ecological niche

    PubMed Central

    2013-01-01

    Background Despite being one of the most intensely studied model organisms, many questions still remain about the evolutionary biology and ecology of Escherichia coli. An important step toward achieving a more complete understanding of E.coli biology entails elucidating relationships between gene content and adaptation to the ecological niche. Results Here, we present genome comparisons of 16 E.coli strains that represent commensals and pathogens isolated from infants during a specific time period in Trondheim, Norway. Using differential gene content, we characterized enrichment profiles of the collection of strains relating to phylogeny, early vs. late colonization, pathogenicity and growth rate. We found clear gene content distinctions relating to the various grouping criteria. We also found that different categories of strains use different genetic elements for similar biological processes. The sequenced genomes included two pairs of strains where each pair was isolated from the same infant at different time points. One pair, in which the strains were isolated four months apart, showed maintenance of an early colonizer genome profile but also gene content and codon usage changes toward the late colonizer profile. Lastly, we placed our sequenced isolates into a broader genomic context by comparing them with 25 published E.coli genomes that represent a variety of pathotypes and commensal strains. This analysis demonstrated the importance of geography in shaping strain level gene content profiles. Conclusions Our results indicate a general pattern where alternative genetic pathways lead toward a consistent ecological role for E.coli as a species. Within this framework however, we saw selection shaping the coding repertoire of E.coli strains toward distinct ecotypes with different phenotypic properties. PMID:23384204

  17. Impact of carbapenem heteroresistance among clinical isolates of invasive Escherichia coli in Chongqing, southwestern China.

    PubMed

    Sun, J D; Huang, S F; Yang, S S; Pu, S L; Zhang, C M; Zhang, L P

    2015-05-01

    Although heteroresistance is common in a wide range of microorganisms, carbapenem heteroresistance among invasive Escherichia coli infections has not been reported. The objective of this study was to evaluate the clinical significance of carbapenem heteroresistance and to identify risk factors for its acquisition. A case-control study was conducted at a 3200-bed teaching hospital in Chongqing, southwestern China. Successive and non-duplicate nosocomial E. coli isolates (n = 332) were obtained from July 2011 to June 2013. Bloodstream isolates made up 50.6% of the strains collected. The rates of heteroresistance were 25.0% to imipenem, 17.2% to ertapenem, and 3.9% to meropenem. The population analysis profile revealed the presence of subpopulations with higher carbapenem resistance, showing MICs ranging from 2.0-128.0mg/L. Male gender, invasive intervention, antibiotic use and bacterial extended-spectrum β-lactamase (ESBL) production contributed to invasive infections by carbapenem-heteroresistant E. coli (CHEC). The production of ESBL was identified as the common independent risk factor for heteroresistance to both ertapenem and imipenem. Pulsed-field gel electrophoresis revealed clonal diversity among the CHEC isolates. Most importantly, characterization of two successive E. coli strains isolated from the same patient indicated that carbapenem resistance evolved from heteroresistance. In conclusion, the high prevalence of heteroresistance to carbapenem among invasive E. coli merits great attention. Routine detection of ESBLs and the prudent use of imipenem and ertapenem are advocated. The early targeted intervention should be formulated to reduce CHEC infection and carbapenem resistance of E. coli.

  18. Molecular characterisation of Escherichia coli isolated from hospitalised children and adults with urinary tract infection.

    PubMed

    Vollmerhausen, T L; Katouli, M

    2014-06-01

    Urinary tract infection (UTI) is common amongst children and recurs in 10-30 % of cases. The differences between Escherichia coli strains causing UTI among hospitalised children and adults remains to be fully elucidated. Here, we examined the genetic relatedness and virulence gene (VG) profiles of a collection of E. coli causing UTI among hospitalised children and adults. Genetic relatedness among the strains was investigated using random amplified polymorphic DNA (RAPD) analysis and the strains were characterised using a combination of phylogenetic grouping, the ability to form biofilm and the presence of antigen 43 (Ag43) and its five known alleles, as well 20 VGs associated with uropathogenic E. coli (UPEC). RAPD analysis resolved six major clusters, with two clusters (A and B) consisting almost exclusively of E. coli isolated from children. Isolates from children had a higher prevalence of alpha-haemolysin (hlyA, p < 0.05) and group II capsular polysaccharide synthesis genes (kpsMT II, p < 0.01) than adults. In contrast, E. coli strains from adults had a higher prevalence of invasive ibeA (p < 0.05) and Ag43 (agn43) (p < 0.05) genes, and produced significantly (p < 0.001) more biofilm than E. coli from children. Adult isolates also carried significantly (p < 0.05) more agn43 allele RS218 compared to isolates from children, which carried significantly (p < 0.05) more of the agn43 allele bCFT073. Our results suggest that bacterial virulence factors play an important role in UTI among hospitalised children; however, further research will determine whether these findings apply to a larger cohort and other clinical settings for UTI in children and adults.

  19. Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh

    PubMed Central

    2011-01-01

    Background Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Methods Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. Results All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm). Conclusion Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary. PMID:21406097

  20. A survey of the antimicrobial susceptibility of Escherichia coli isolated from Sable Island horses.

    PubMed

    Timonin, M E; Poissant, J; McLoughlin, P D; Hedlin, C E; Rubin, J E

    2017-03-01

    The feral horses of Sable Island are a geographically isolated population located ∼160 km off the east coast of Nova Scotia, Canada. Because these horses have no contact with domestic animals, have minimal contact with people, and have never received antimicrobials, they offer a unique opportunity to study the dissemination of antimicrobial resistance in unmanaged populations. As part of an ongoing multidisciplinary and individual-based monitoring program, we collected feces from 508 geolocalized horses (92% of the total population) between July and September 2014. We selectively cultured Escherichia coli on MacConkey and CHROMagar ESBL media. Antimicrobial susceptibilities were determined, and organisms resistant to β-lactam antimicrobials were screened for β-lactamase genes by PCR. Escherichia coli was recovered from 146 (28.7%) individuals, and the majority of isolates (97%) were susceptible to all drugs tested. Resistance to tetracycline was most common, including organisms isolated from 4 (2.7%) of the colonized horses. A single isolate resistant to ampicillin, ceftriaxone, and ceftiofur was identified, which possessed the CTX-M-1 gene. Our findings demonstrate that although antimicrobial resistance is not common in this remote population, clinically relevant resistance genes are present.

  1. Diversity of CRISPR loci and virulence genes in pathogenic Escherichia coli isolates from various sources.

    PubMed

    Jiang, Yun; Yin, Shuang; Dudley, Edward G; Cutter, Catherine N

    2015-07-02

    Shiga toxin-producing Escherichia coli (STEC) strains, including those of O157:H7 and the "big six" serogroups (i.e., O26, O45, O103, O111, O121, and O145) are food-borne pathogens that pose a serious health threat to humans. Ruminants, especially cattle, are a major reservoir for O157 and non-O157 STEC. In the present study, 115 E. coli strains isolated from small and very small beef processing plants were screened for virulence genes (stx1, stx2, eae) using a multiplex polymerase chain reaction (PCR). Thirteen (11.3%) of the 115 isolates tested positive for stx1, stx2, or eae genes, but only 4 (3.5%) tested positive for either stx1 or stx2. A multiplex PCR reaction targeting eight O-serogroups (O26, O45, O103, O111, O113, O121, O145, O157) identified 12 isolates as O26, O103, O111, or O145, with E. coli O26 being the most predominant serogroup (61.5%). The thirteen isolates were further analyzed using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) subtyping. Consistent with previous studies, CRISPR alleles from strains of the same serogroup were similar in their spacer content and order, regardless of the isolation source. A completely different CRISPR allele was observed in one isolate ("7-J") which exhibited a different O-serogroup (O78). Our results confirmed previous findings that CRISPR loci are conserved among phylogenetically-related strains. In addition, 8 E. coli O26 isolates and a collection of 42 E. coli O26 isolates were screened for 12 enterohemorrhagic E. coli-specific genes. Seven genes (ECs848-Hypothetical Protein, ECs2226-Hypothetical Protein, ECs3857-nleB, ECs3858-Hypothetical Protein, ECs4552-escF, ECs4553-Hypothetical Protein, and ECs4557-sepL) were found in all 50 isolates. An additional 5 genes (ECs1322-ureA urease subunit γ, ECs1323-ureB urease subunit β, ECs1326-ureF, ECs1561-Hypothetical Protein, and ECs1568-Hypothetical Protein) were found to be highly prevalent in isolates from human sources, while lower in

  2. Investigating the Relatedness of Enteroinvasive Escherichia coli to Other E. coli and Shigella Isolates by Using Comparative Genomics

    PubMed Central

    Hazen, Tracy H.; Leonard, Susan R.; Lampel, Keith A.; Lacher, David W.

    2016-01-01

    Enteroinvasive Escherichia coli (EIEC) is a unique pathovar that has a pathogenic mechanism nearly indistinguishable from that of Shigella species. In contrast to isolates of the four Shigella species, which are widespread and can be frequent causes of human illness, EIEC causes far fewer reported illnesses each year. In this study, we analyzed the genome sequences of 20 EIEC isolates, including 14 first described in this study. Phylogenomic analysis of the EIEC genomes demonstrated that 17 of the isolates are present in three distinct lineages that contained only EIEC genomes, compared to reference genomes from each of the E. coli pathovars and Shigella species. Comparative genomic analysis identified genes that were unique to each of the three identified EIEC lineages. While many of the EIEC lineage-specific genes have unknown functions, those with predicted functions included a colicin and putative proteins involved in transcriptional regulation or carbohydrate metabolism. In silico detection of the Shigella virulence plasmid (pINV), which is essential for the invasion of host cells, demonstrated that a form of pINV was present in nearly all EIEC genomes, but the Mxi-Spa-Ipa region of the plasmid that encodes the invasion-associated proteins was absent from several of the EIEC isolates. The comparative genomic findings in this study support the hypothesis that multiple EIEC lineages have evolved independently from multiple distinct lineages of E. coli via the acquisition of the Shigella virulence plasmid and, in some cases, the Shigella pathogenicity islands. PMID:27271741

  3. Change of integrons over time in Escherichia coli isolates recovered from healthy pigs and chickens.

    PubMed

    Marchant, Mauricio; Vinué, Laura; Torres, Carmen; Moreno, Miguel A

    2013-04-12

    The aims of this study were (a) to perform a time-related quantitative analysis of relative integron frequencies in intestinal Escherichia coli isolates from food animals (pigs and chickens) and (b) to analyse putative relationships between integrons, antimicrobial resistance and phylogenetic groups. The E. coli collection of the Spanish Veterinary Antimicrobial Resistance Surveillance Network was used to extract 393 intestinal isolates from healthy pigs and chickens belonging to the oldest (1998/99) and the latest (2006) available surveillance programs, and their quantitative antimicrobial resistance data. PCR and sequencing were used for detection and characterisation of integrons. Integron overall relative frequencies ranged between 80% and 49%, being higher in pig than in chicken E. coli isolates in both periods. Time-related analysis showed no variations when considering overall frequencies (80% versus 75% in pig E. coli isolates and 49% versus 51% in E. coli chicken isolates). Apart from the 3'-integron sul gene, six different antimicrobial-related gene cassettes (with different variants) were detected in the sequenced integron variable regions: aadA, dfrA, and sat in classes 1 and 2, and cmlA, linF and aadB only in class 1. Multiresistance profiles showed a high association between antimicrobial resistance and integron presence for those antimicrobials corresponding to the antimicrobial-related gene cassettes detected (streptomycin, trimethoprim, chloramphenicol, plus sulphonamides). However, the presence of integrons was also associated with resistance to amoxicillin and tetracycline, two antimicrobials that are widely used in animals but not linked to these genetic elements. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Taqman real-time PCR assays for rapid detection of avian pathogenic Escherichia coli isolates.

    PubMed

    Ikuta, Nilo; De Oliveira Solla Sobral, Fabiana; Lehmann, Fernanda Kieling Moreira; da Silveira, Proença Vinicius; de Carli, Silvia; Casanova, Yara Silva; Celmer, Álvaro José; Fonseca, André Salvador Kazantzi; Lunge, Vagner Ricardo

    2014-12-01

    Avian pathogenic Escherichia coli (APEC) isolates are currently differentiated from nonpathogenic strains by classical PCR of virulence genes. This study improves the detection of the five main virulence genes used for APEC detection with the development of duplex and single Taqman real-time PCR to these targets. Primers and probes targeted to ompT, hlyF, iroN, iutA, and iss genes were designed and used in the implementation of single (iss) and duplex (hlyF/ompT and iroN/iutA) Taqman PCR assays. All five virulence genes of E coli strains were successfully detected by classical and Taqman real-time (single and duplex) PCR. A panel of 111 E coli isolates, obtained from avian samples collected in different Brazilian regions between 2010 and 2011, were further tested by both assays. Complete agreement was observed in the detection of four genes, ompT, hlyF, iron, iutA, but not for iss. This issue was addressed by combining the forward primer of the classical PCR to the new iss reverse primer and probe, resulting in complete agreement for all five genes. In total, 61 (55%) Brazilian E. coli isolates were detected as APEC, and the remaining 50 (45%) as avian fecal E. coli (AFEC). In conclusion, classical and Taqman real-time PCR presented exactly the same analytical performance for the differentiation of APEC and AFEC isolates. The developed real-time Taqman PCR assays could be used for the detection and differentiation of APEC isolates.

  5. Environmental phosphate differentially affects virulence phenotypes of uropathogenic Escherichia coli isolates causative of prostatitis

    PubMed Central

    Grillo-Puertas, M; Martínez-Zamora, MG; Rintoul, MR; Soto, SM; Rapisarda, VA

    2015-01-01

    K-12 Escherichia coli cells grown in static media containing a critical phosphate (Pi) concentration ≥25 mM maintained a high polyphosphate (polyP) level in stationary phase, impairing biofilm formation, a phenomenon that is triggered by polyP degradation. Pi concentration in human urine fluctuates according to health state. Here, the influence of environmental Pi concentration on the occurrence of virulence traits in uropathogenic E. coli (UPEC) isolated from acute prostatitis patients was evaluated. After a first screening, 3 isolates were selected according to differential biofilm formation profiles depending on media Pi concentration. For each isolate, biofilm positive and negative conditions were established. Regardless of the isolate, biofilm formation capacity was accompanied with curli and cellulose production and expression of some key virulence factors associated with adhesion. When the selected isolates were grown in their non-biofilm-forming condition, low concentrations of nalidixic acid and ciprofloxacin induced biofilm formation. Interestingly, similar to laboratory strains, polyP degradation induced biofilm formation in the selected isolates. Data demonstrated the complexity of UPEC responses to environmental Pi and the importance of polyP metabolism in the virulence of clinical isolates. PMID:26083279

  6. Molecular analysis of typical and atypical enteropathogenic Escherichia coli (EPEC) isolated from children with diarrhoea.

    PubMed

    Nakhjavani, Farrokh Akbari; Emaneini, Mohammad; Hosseini, Hossein; Iman-Eini, Hossein; Aligholi, Marzieh; Jabalameli, Fereshteh; Haghi-Ashtiani, Mohammad Taghi; Taherikalani, Morovat; Mirsalehian, Akbar

    2013-02-01

    Diarrhoea continues to be one of the most common causes of morbidity and mortality among infants and children in developing countries. To investigate the incidence, antimicrobial resistance and genetic relationships of enteropathogenic Escherichia coli (EPEC) in children with diarrhoea, a total of 612 stool specimens were collected in Tehran, Iran, and cultured to isolate strains of EPEC. The disc diffusion method was used to determine the susceptibility of the isolates according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. The presence of eae, stx and bfp-A genes was determined by PCR. The genetic relationships between EPEC isolates were determined by pulsed-field gel electrophoresis (PFGE). Out of the 412 strains of E. coli obtained from 612 diarrhoeal stool specimens, 23 (5.6 %) were identified as EPEC, of which seven (30.4 %) were classified as typical strains of EPEC and 16 (69.6 %) were classified as atypical. Out of the 23 EPEC isolates, 69.5 % were resistant to ampicillin, 39.1 % were resistant to tetracycline and cotrimoxazole, 30.4 % were resistant to cefpodoxime, ceftazidime, ceftriaxone and aztreonam, and 26.1 % were resistant to imipenem. The isolates were classified into 21 pulsotypes by PFGE profiles. The present study shows that typical and atypical EPEC isolates displayed considerable heterogeneity in PFGE profiles and EPEC infections were only sporadic in Tehran. Overall 69 % of isolates were resistant to at least one of the antibiotics tested.

  7. Investigation of antimicrobial resistance in Escherichia coli and enterococci isolated from Tibetan pigs.

    PubMed

    Li, Peng; Wu, Dongfang; Liu, Kunyao; Suolang, Sizhu; He, Tao; Liu, Xuan; Wu, Congming; Wang, Yang; Lin, Degui

    2014-01-01

    This study investigated the antimicrobial resistance of Escherichia coli and enterococci isolated from free-ranging Tibetan pigs in Tibet, China, and analyzed the influence of free-ranging husbandry on antimicrobial resistance. A total of 232 fecal samples were collected from Tibetan pigs, and the disk diffusion method was used to examine their antimicrobial resistance. Broth microdilution and agar dilution methods were used to determine minimum inhibitory concentrations for antimicrobial agents for which disks were not commercially available. A total of 129 E. coli isolates and 84 Enterococcus isolates were recovered from the fecal samples. All E. coli isolates were susceptible to amoxicillin/clavulanic acid, and 40.4% were resistant to tetracycline. A small number of isolates were resistant to florfenicol (27.9%), ampicillin (27.9%), sulfamethoxazole/trimethoprim (19.4%), nalidixic acid (19.4%), streptomycin (16.2%) and ceftiofur (10.9%), and very low resistance rates to ciprofloxacin (7.8%), gentamicin (6.9%), and spectinomycin (2.3%) were observed in E. coli. All Enterococcus isolates, including E. faecium, E. faecalis, E. hirae, and E. mundtii, were susceptible to amoxicillin/clavulanic acid and vancomycin, but showed high frequencies of resistance to oxacillin (92.8%), clindamycin (82.1%), tetracycline (64.3%), and erythromycin (48.8%). Resistance rates to florfenicol (17.9%), penicillin (6.0%), ciprofloxacin (3.6%), levofloxacin (1.2%), and ampicillin (1.2%) were low. Only one high-level streptomycin resistant E. faecium isolate and one high-level gentamicin resistant E. faecium isolate were observed. Approximately 20% and 70% of E. coli and Enterococcus isolates, respectively, were defined as multidrug-resistant. In this study, E. coli and Enterococcus isolated from free-ranging Tibetan pigs showed relatively lower resistance rates than those in other areas of China, where more intensive farming practices are used. These results also revealed that free

  8. Characterization of Globally Spread Escherichia coli ST131 Isolates (1991 to 2010)

    PubMed Central

    Novais, Ângela; Pires, João; Ferreira, Helena; Costa, Luísa; Montenegro, Carolina; Vuotto, Claudia; Donelli, Gianfranco; Coque, Teresa M.

    2012-01-01

    The characterization of a broad representative sample of ST131 Escherichia coli isolates from different origins and settings (1991 to 2010) revealed that this clonal group has likely diversified recently and that the expansion of particular variants has probably been favored by the capture of diverse, multidrug-resistant IncFII plasmids (pC15-1a, pEK499, pKF3-140-like). The low ability to adhere and to grow as biofilm that was detected in this study suggests unknown mechanisms for the persistence of this clonal group which need to be further explored. PMID:22491693

  9. Antimicrobial resistance in commensal Escherichia coli isolated from animals at slaughter

    PubMed Central

    Wasyl, Dariusz; Hoszowski, Andrzej; Zając, Magdalena; Szulowski, Krzysztof

    2013-01-01

    Monitoring of antimicrobial resistance in commensal Escherichia coli (N = 3430) isolated from slaughtered broilers, laying hens, turkeys, swine, and cattle in Poland has been run between 2009 and 2012. Based on minimal inhibitory concentration (MIC) microbiological resistance to each of 14 tested antimicrobials was found reaching the highest values for tetracycline (43.3%), ampicillin (42.3%), and ciprofloxacin (39.0%) whereas the lowest for colistin (0.9%), cephalosporins (3.6 ÷ 3.8%), and florfenicol (3.8%). The highest prevalence of resistance was noted in broiler and turkey isolates, whereas it was rare in cattle. That finding along with resistance patterns specific to isolation source might reflect antimicrobial consumption, usage preferences or management practices in specific animals. Regression analysis has identified changes in prevalence of microbiological resistance and shifts of MIC values. Critically important fluoroquinolone resistance was worrisome in poultry isolates, but did not change over the study period. The difference (4.7%) between resistance to ciprofloxacin and nalidixic acid indicated the scale of plasmid-mediated quinolone resistance. Cephalosporin resistance were found in less than 3.8% of the isolates but an increasing trends were observed in poultry and MIC shift in the ones from cattle. Gentamycin resistance was also increasing in E. coli of turkey and cattle origin although prevalence of streptomycin resistance in laying hens decreased considerably. Simultaneously, decreasing MIC for phenicols observed in cattle and layers isolates as well as tetracycline values in E. coli from laying hens prove that antimicrobial resistance is multivariable phenomenon not only directly related to antimicrobial usage. Further studies should elucidate the scope of commensal E. coli as reservoirs of resistance genes, their spread and possible threats for human and animal health. PMID:23935596

  10. Phenotypic and genotypic characterization of enteroaggregative Escherichia coli isolates from pediatric population in Pakistan.

    PubMed

    Khalil, Uzma; Younus, Mahwish; Asghar, Naeem; Siddiqui, Fariha; Gómez-Duarte, Oscar G; Wren, Brendan W; Bokhari, Habib

    2016-10-01

    Enteroaggregative Escherichia coli (EAEC) are a leading cause of diarrhea among children. The objective of this study was to define the frequency of EAEC among diarrheal children from flood-affected areas as well as sporadic cases, determine multidrug resistance, and evaluation of virulence using an in vivo model of pathogenesis. Stool samples were collected from 225 diarrheal children from 2010 to 2011 from flood-affected areas as well as from sporadic cases in Pakistan. Identified EAEC isolates were characterized by phylogrouping, antibiotic resistance patterns including the extended-spectrum beta lactamase spectrum, single nucleotide polymorphism detection in gyrA and parC, and virulence potential using wax worm, G. mellonella. A total of 35 (12.5%) confirmed EAEC isolates were identified among 225 E. coli isolates. EAEC isolates displayed high resistance to tetracycline, ampicillin, and cefaclor. A total of 34.28% were ESBL positive. Single nucleotide polymorphism detection revealed 37.14% and 68.57% isolates were positive for SNPs in gyrA (A660 -T660 ) and parC (C330 -T330 ), respectively. Phylogrouping revealed that B2 phylogroup was more prevalent among all EAEC isolates tested followed by D, A, B1, and non-typeable (NT). Infection of G. mellonella with EAEC showed that killing infective dose was 100% higher than E. coli DH5 alpha control. EAEC are prevalent among Pakistani children with diarrhea, they are highly resistant to antibiotics, and predominantly fall into B2 phylogroup. Epidemiologic surveillance of EAEC and other E. coli pathotypes is critical to assess not only the role of these pathogens in diarrheal disease but also to determine the extent of multidrug resistance among the population.

  11. Occurrence of class 1 integrons in uropathogenic fluoroquinolone-resistant clinical Escherichia coli isolates from Jamaica.

    PubMed

    Stephenson, Stacy A M; Brown, Paul D

    2013-03-01

    Quinolone resistance is generally caused by chromosomal mutations, but has been more recently found associated with the plasmid-mediated qnr genes. The objective of this study was to screen and analyse polymorphisms of integrons in clinical isolates of Escherichia coli in Jamaica. Previous studies in Jamaica identified fluoroquinolone resistance in predominantly uropathogenic E. coli clinical isolates: 45% harbouring qnrA, qnrB and/or qnrS, and 17% were (Extended-spectrum beta-lactamase) ESBL-producers. These isolates were analysed for the presence and variation of class 1 and 2 integrase genes, 5'- and 3'- conserved segments and the Orf513 recombinase gene by primer-specific polymerase chain reaction (PCR) and restriction fragment-length polymorphism (RFLP). Results indicated integron-encoded integrases in 93% of isolates primarily harbouring class 1 integrase genes; four of 58 isolates carried both classes. The Orf513 and 5'- and 3'-conserved segment (CS) regions were identified in 83% and 55% of the isolates respectively. RFLP evaluation of the 5'- and 3'-CS regions in int1-positive strains yielded two main types. The reduced diversity, but wide dispersion of class 1 integrons harbouring qnr genes may give rise to the conservation of the mobile genetic elements in which they are carried. © 2012 The Authors APMIS © 2012 APMIS.

  12. Characterization of multi-antibiotic-resistant Escherichia coli Isolated from beef cattle in Japan.

    PubMed

    Yamamoto, Shiori; Nakano, Motoki; Kitagawa, Wataru; Tanaka, Michiko; Sone, Teruo; Hirai, Katsuya; Asano, Kozo

    2014-01-01

    The emergence of multiple-antibiotic-resistance bacteria is increasing, which is a particular concern on livestock farms. We previously isolated 1,347 antimicrobial-resistant (AMR) Escherichia coli strains from the feces of beef cattle on 14 Japanese farms. In the present study, the genetic backgrounds and phylogenetic relationships of 45 AMR isolates were characterized by the chromosome phylotype, AMR phenotype, AMR genotype, and plasmid type. These isolates were classified into five chromosome phylotypes, which were closely linked to the farms from which they were isolated, suggesting that each farm had its own E. coli phylotype. AMR phenotype and plasmid type analyses yielded 8 and 14 types, all of which were associated with the chromosomal phylotype and, thus, to the original farms. AMR genotype analysis revealed more variety, with 16 types, indicating both inter- and intra-farm diversity. Different phylotype isolates from the same farm shared highly similar plasmid types, which indicated that plasmids with AMR genes could be transferred between phylotypes, thereby generating multi-antibiotic-resistant microorganisms. This ecological study demonstrated that the chromosome phylotype was strongly correlated with the farm from which they were isolated, while the AMR phenotype, genotype, and plasmid type were generally correlated with the chromosome phylotype and farm source.

  13. Characteristics of Escherichia coli strains belonging to enteropathogenic E. coli serogroups isolated in Italy from children with diarrhea.

    PubMed Central

    Giammanco, A; Maggio, M; Giammanco, G; Morelli, R; Minelli, F; Scheutz, F; Caprioli, A

    1996-01-01

    Fifty-five Escherichia coli strains belonging to enteropathogenic E. coli (EPEC) serogroups were examined for phenotypic and genetic factors associated with virulence. The strains were isolated in Italy from children with diarrhea and identified as EPEC by clinical laboratories using commercially available antisera. O:H serotyping showed that 35 strains (27 of O26, O111, and O128 serogroups) belonged to 11 serotypes considered to be classical EPEC O:H serotypes. The other 20 isolates were classified as 15 nonclassical EPEC O:H serotypes. All the potential EPEC virulence factors associated with bacterial adhesion (localized adherence, fluorescentactin staining test positivity, presence of the attaching and effacing [eaeA] gene), the production of verotoxin, and the positivity with the enterohemorrhagic E. coli probe were significantly more frequent among isolates belonging to classical than nonclassical serotypes. Strains displaying an aggregative adhesion and hybridizing with the enteroaggregative DNA probe were found in serogroups O86, O111, and O126. Verotoxin-producing isolates belonged to serogroups O26, O111, and O128. Only one of the isolates hybridized with the EPEC adherence factor (EAF) probe, but 33 strains gave positive results with the eae probe, confirming that the former is more suitable in epidemiological studies in European countries. These results indicate that up to 75% of strains identified as EPEC by commercial antisera may possess potential virulence properties and/or belong to classical EPEC O:H serotypes and suggest that O grouping is still a useful diagnostic tool for presumptive identification of diarrheagenic E. coli in clinical laboratories. PMID:8904439

  14. Isolation of the lux genes from Photobacterium leiognathi and expression in Escherichia coli.

    PubMed

    Delong, E F; Steinhauer, D; Israel, A; Nealson, K H

    1987-01-01

    Genes necessary for luminescence (lux genes) in the marine bacterium Photobacterium leiognathi, strain PL721, were isolated and expressed in Escherichia coli. A 15-kb fragment obtained from a partial digestion of PL721 DNA with HindIII was cloned into the plasmid pACYC184, resulting in the hybrid plasmid pSD721. When pSD721 was transformed into E. coli ED8654, the resulting transformants were luminous with no additions to the cells, indicating that it contained the structural genes coding for the alpha and beta subunits of luciferase (luxA and luxB), and for components involved in aldehyde biosynthesis. Hybridization analysis with luxA and luxB 32P probes confirmed the location of these two genes on the 15-kb insert. When pSD721 was transformed into four different strains of E. coli, luminescence expression varied widely in amount and in pattern. In some strains, luminescence developed like an autoinducible system, and at maximum induction was very bright, even with no addition of aldehyde, while in others, luminescence was 100-fold less, and no induction was seen. In no case was luminescence affected by shifts in temperature, osmolarity, or iron concentration. These results indicate that, while the complete lux regulon is apparently contained on the 15-kb cloned fragment, the regulation of the lux regulon in pSD721 is subject to host controls by E. coli, controls which vary widely among different E. coli strains.

  15. ANTIMICROBIAL RESISTANCE OF ESCHERICHIA COLI STRAINS ISOLATED FROM URINE AT OUTPATIENT POPULATION: A SINGLE LABORATORY EXPERIENCE

    PubMed Central

    Vranic, Sabina Mahmutovic; Uzunovic, Aida

    2016-01-01

    Objectives: The aim of this study was to examine antimicrobial resistance of Escherichia coli strains isolated from urine in outpatient population. Material and methods: We performed a retrospective study for tree months period, between January 1st and March 31st, 2015, at the Department of Microbiology and Parasitology, Faculty of Medicine, University of Sarajevo. We determined the E. coli antimicrobial resistance in 556 first urine samples from outpatient population of Hrasno community in Sarajevo, Bosnia and Herzegovina. E. coli is the most frequent agent causing urinary tract infections in outpatients as well. The standard methods of descriptive statistics were performed for data analysis. Results: We observed the highest antimicrobial resistance of E. coli for ampicillin (82,79%), followed by trimethoprim-sulfamethoxazole (40,86%), nalidixic acid (19,35%), cephazolin (7,52%), nitrofurantoin (5,37%), gentamicin (2,15%) and ciprofloxacin (4,30%). Conclusions: The results of study showed that E. coli has the highest resistance to ampicillin and trimethoprim-sulfamethoxazole in outpatient population of Hrasno community. PMID:27147918

  16. Characteristics of ciprofloxacin and cephalosporin resistant Escherichia coli isolated from turkeys in Great Britain.

    PubMed

    Randall, L P; Mueller-Doblies, D; Lemma, F L; Horton, R A; Teale, C J; Davies, R H

    2013-01-01

    1. A field study was performed to investigate the presence and characteristics of ciprofloxacin-resistant, extended spectrum β-lactamase (ESBL) and AmpC Escherichia coli from turkeys in Great Britain. E. coli were isolated from ~9000 boot swab samples from 27 different farms owned by four different companies. Between 1 and 14 visits were made to each farm (mean 3) at between 0 and 15 m intervals (mean ~5 m). 2. CHROMagar ECC with and without ciprofloxacin or cephalosporin antibiotics was used as selective isolation media. Representative isolates with different phenotypes were tested for mutations in gyrA and for: qnrA, B, S, qepA and aac(6')-Ib genes, for ESBL phenotype, the presence of bla genes and plasmid type, and for ampC genes Representative ciprofloxacin-resistant and CTX-M isolates were further tested for serotype and PFGE type. On ciprofloxacin selective media 55% of samples yielded ciprofloxacin resistant E. coli and of those further analysed, most had ciprofloxacin MICs >4 mg/l and mutations in gyrA. 3. For the different companies, the mean number of samples per farm with cefoxitin- or cefotaxime-resistant isolates ranged from 1·0% to 61·9% and 4·7% to 31·7% respectively. Cefotaxime-resistance was most commonly associated with an ESBL phenotype, a CTX-M-1 or CTX-M-14 sequence type and an I1-γ or K plasmid inc type. The mechanism of cefoxitin resistance was not determined for most isolates, but where determined it was bla . 4. PFGE and serotyping showed clonally-related isolates persisting over multiple visits suggesting both more prudent use of antibiotics and improved farm hygiene are needed to address the issue of antimicrobial resistance in isolates from turkeys.

  17. Transferability of antimicrobial resistance from multidrug-resistant Escherichia coli isolated from cattle in the United States to Escherichia coli and Salmonella Newport recipients.

    PubMed

    Poole, T L; Callaway, T R; Norman, K N; Scott, H M; Loneragan, G H; Ison, S A; Beier, R C; Harhay, D M; Norby, B; Nisbet, D J

    2017-08-08

    To evaluate conjugative transfer of cephalosporin resistance among (n=100) strains of multi-drug resistant Escherichia coli (MDRE) to Salmonella Newport and E. coli DH5α recipients. Phenotypic and genotypic profiles were determined for MDRE, Salmonella Newport (trSN) and E. coli DH5α (trDH) transconjugants. Twenty-seven percent (n=26) and 28% (n=27) of (n=95) MDR E. coli donor isolates transferred resistance to trSN and trDH recipient isolates, respectively. Twenty-seven percent (n=27) of MDRE were confirmed as extended-spectrum β-lactamase (ESBL) based on the double disc synergy assay and whole genome sequencing (WGS). WGS was performed on 25 of the ESBLs. Subsequently, two isolates carried blaCTX-M-6, 20 possessed blaCTX-M-32, and three were negative for blaCTX-M genes. Fourteen of the ESBLs sequenced harboured qnrB19. Differential transfer of IncA/C and IncN from MDRE32 was observed between trSN32 and trDH32. IncN positive trDH32 displayed an ESBL phenotype; whereas, IncA/C positive trSN32 displayed an AmpC phenotype. ESBL transfer to SN and DH recipients occurred at 11% and 92% respectively. Twenty-seven MDRE were phenotypically identified ESBLs. WGS of 25 MDRE revealed that two and 20 isolates carried blaCTX-M-6 and blaCTX-M-32 genes, respectively. One multi-drug resistant isolate exhibited a conversion from an AmpC phenotype to an ESBL phenotype with the transfer of only the IncN plasmid. The rate of resistance transfer to Salmonella or E. coli recipients was nearly identical. However, the ESBL phenotype was transferred with significantly greater prevalence to E. coli as opposed to Salmonella Newport, 96% and 11%, respectively. Copyright © 2017. Published by Elsevier Ltd.

  18. Isolation of atypical enteropathogenic Escherichia coli and Shiga toxin 1 and 2f-producing Escherichia coli from avian species in India.

    PubMed

    Farooq, S; Hussain, I; Mir, M A; Bhat, M A; Wani, S A

    2009-06-01

    To study the prevalence and characterize atypical enteropathogenic Escherichia coli (EPEC) and Shiga toxin producing E. coli (STEC) in avian species in India. Two hundred and twelve faecal samples collected from 62 chickens, 50 ducks and 100 pigeons were investigated for the presence of stx(1), stx(2), eae and ehxA virulence genes by multiplex PCR. In all, 42 E. coli isolates (25 chicken, 2 duck and 15 pigeon) possessed at least one virulence gene. Out of these, nine (4.24%) isolates were STEC and 33 (15.56%) were EPEC. All isolates from duck and chicken were EPEC while among 15 pigeon isolates nine (60%) were STEC and six (40%) were EPEC. Among the STEC isolates four each carried stx(1) or stx(2) and one possessed both stx(1) and stx(2). Subtype analysis of stx revealed the presence of stx(2f) in four STEC isolates. None of the STEC isolates carried stx(1c), stx(2c), stx(2d) or stx(2e). Isolates carrying stx(2f) demonstrated vero cell toxicity. One each belonged to serogroup O17 and O78, while one was rough and the other untypeable. All EPEC isolates were atypical as they lacked bfpA. This appears to be the first report of detection of stx(2f) from India. The study established the presence of stx(1) and stx(2f) containing E. coli in pigeons and atypical EPEC in poultry in India. Pigeons might serve as vectors for transmission of STEC to environment and humans. Taking into account the close contact between fanciers and pigeons, these findings warrant a more critical appraisal of these zoonotic pathogens in pigeons and humans.

  19. Bioconversion of glycerol for bioethanol production using isolated Escherichia coli ss1

    PubMed Central

    Suhaimi, Sheril Norliana; Phang, Lai-Yee; Maeda, Toshinari; Abd-Aziz, Suraini; Wakisaka, Minato; Shirai, Yoshihito; Hassan, Mohd Ali

    2012-01-01

    Bioconverting glycerol into various valuable products is one of glycerol's promising applications due to its high availability at low cost and the existence of many glycerol-utilizing microorganisms. Bioethanol and biohydrogen, which are types of renewable fuels, are two examples of bioconverted products. The objectives of this study were to evaluate ethanol production from different media by local microorganism isolates and compare the ethanol fermentation profile of the selected strains to use of glucose or glycerol as sole carbon sources. The ethanol fermentations by six isolates were evaluated after a preliminary screening process. Strain named SS1 produced the highest ethanol yield of 1.0 mol: 1.0 mol glycerol and was identified as Escherichia coli SS1 Also, this isolated strain showed a higher affinity to glycerol than glucose for bioethanol production. PMID:24031858

  20. Prevalence of virulence factors in Escherichia coli isolated from healthy animals and water sources in Brazil.

    PubMed

    Carlos, Camila; Alexandrino, Fabiana; Vieira, Monica A M; Stoppe, Nancy C; Sato, Maria Inês Z; Gomes, Tânia A T; Ottoboni, Laura M M

    2011-03-01

    The aim of this work was to verify the presence of seven virulence factors (ST, LT, eae, stx(1), stx(2), INV and EAEC) among Escherichia coli strains isolated from healthy humans, bovines, chickens, sheep, pigs and goats, from two sewage treatment plants and from the Tietê River. We have found a high prevalence of eae, stx(1) and stx(2) in ruminants. The EAEC gene was only found in humans and sewage. No strains presented ST, LT or INV. BOX-PCR fingerprints revealed a high diversity among the strains analysed and a non-clonal origin of strains that presented the same virulence factors. Therefore, we concluded that ruminants may constitute an important reservoir of most diarrheagenic E. coli in Brazil, except for EAEC strains. These results emphasize the importance of the identification of the animal source of fecal contamination for the correct water risk assessment.

  1. Comprehensive Characterization of Escherichia coli O104:H4 Isolated from Patients in the Netherlands

    PubMed Central

    Ferdous, Mithila; Zhou, Kai; de Boer, Richard F.; Friedrich, Alexander W.; Kooistra-Smid, Anna M. D.; Rossen, John W. A.

    2015-01-01

    In 2011, a Shiga toxin-producing Enteroaggregative Escherichia coli (EAEC Stx2a+) O104:H4 strain caused a serious outbreak of acute gastroenteritis and hemolytic-uremic syndrome (HUS) in Germany. In 2013, E. coli O104:H4 isolates were obtained from a patient with HUS and her friend showing only gastrointestinal complaints. The antimicrobial resistance and virulence profiles of these isolates together with three EAEC Stx2a+ O104:H4 isolates from 2011 were determined and compared. Whole-genome sequencing (WGS) was performed for detailed characterization and to determine genetic relationship of the isolates. Four additional genomes of EAEC Stx2a+ O104:H4 isolates of 2009 and 2011 available on NCBI were included in the virulence and phylogenetic analysis. All E. coli O104:H4 isolates tested were positive for stx2a, aatA, and terD but were negative for escV. All, except one 2011 isolate, were positive for aggR and were therefore considered EAEC. The EAEC Stx2a+ O104:H4 isolates of 2013 belonged to sequence type (ST) ST678 as the 2011 isolates and showed slightly different resistance and virulence patterns compared to the 2011 isolates. Core-genome phylogenetic analysis showed that the isolates of 2013 formed a separate cluster from the isolates of 2011 and 2009 by 27 and 20 different alleles, respectively. In addition, only a one-allele difference was found between the isolate of the HUS-patient and that of her friend. Our study shows that EAEC Stx2a+ O104:H4 strains highly similar to the 2011 outbreak clone in their core genome are still circulating necessitating proper surveillance to prevent further outbreaks with these potentially pathogenic strains. In addition, WGS not only provided a detailed characterization of the isolates but its high discriminatory power also enabled us to discriminate the 2013 isolates from the isolates of 2009 and 2011 expediting the use of WGS in public health services to rapidly apply proper infection control strategies. PMID:26696970

  2. Comprehensive Characterization of Escherichia coli O104:H4 Isolated from Patients in the Netherlands.

    PubMed

    Ferdous, Mithila; Zhou, Kai; de Boer, Richard F; Friedrich, Alexander W; Kooistra-Smid, Anna M D; Rossen, John W A

    2015-01-01

    In 2011, a Shiga toxin-producing Enteroaggregative Escherichia coli (EAEC Stx2a+) O104:H4 strain caused a serious outbreak of acute gastroenteritis and hemolytic-uremic syndrome (HUS) in Germany. In 2013, E. coli O104:H4 isolates were obtained from a patient with HUS and her friend showing only gastrointestinal complaints. The antimicrobial resistance and virulence profiles of these isolates together with three EAEC Stx2a+ O104:H4 isolates from 2011 were determined and compared. Whole-genome sequencing (WGS) was performed for detailed characterization and to determine genetic relationship of the isolates. Four additional genomes of EAEC Stx2a+ O104:H4 isolates of 2009 and 2011 available on NCBI were included in the virulence and phylogenetic analysis. All E. coli O104:H4 isolates tested were positive for stx2a, aatA, and terD but were negative for escV. All, except one 2011 isolate, were positive for aggR and were therefore considered EAEC. The EAEC Stx2a+ O104:H4 isolates of 2013 belonged to sequence type (ST) ST678 as the 2011 isolates and showed slightly different resistance and virulence patterns compared to the 2011 isolates. Core-genome phylogenetic analysis showed that the isolates of 2013 formed a separate cluster from the isolates of 2011 and 2009 by 27 and 20 different alleles, respectively. In addition, only a one-allele difference was found between the isolate of the HUS-patient and that of her friend. Our study shows that EAEC Stx2a+ O104:H4 strains highly similar to the 2011 outbreak clone in their core genome are still circulating necessitating proper surveillance to prevent further outbreaks with these potentially pathogenic strains. In addition, WGS not only provided a detailed characterization of the isolates but its high discriminatory power also enabled us to discriminate the 2013 isolates from the isolates of 2009 and 2011 expediting the use of WGS in public health services to rapidly apply proper infection control strategies.

  3. Antimicrobial resistance in fecal Escherichia coli isolated from growing chickens on commercial broiler farms.

    PubMed

    Ozaki, Hiroichi; Esaki, Hidetake; Takemoto, Kouhei; Ikeda, Akira; Nakatani, Yasutaka; Someya, Azusa; Hirayama, Norio; Murase, Toshiyuki

    2011-05-12

    To investigate the effects of rearing practices of commercial broiler chickens on the incidence of antimicrobial resistance in commensal Escherichia coli isolates, fecal E. coli isolates obtained in 4 farms were screened for anitimicrobial resistance. Ten E. coli isolates were recovered from each of the fecal samples collected from 10 birds in the farms at the ages of 2 days, 14-17 days, and 47-50 days. In 2 out of the 4 farms, no antimicrobials were used during the rearing period. In the other two farms, following collection of the fecal samples at 14 and 15 days of age, oxytetracycline (OTC), sulfadimethoxine (SDMX), and tylosin were given to birds on one farm and SDMX was used in the other. Isolates resistant to ampicillin and OTC that were obtained from an untreated flock at different sampling times were closely related to each other by pulsed-field gel electrophoresis patterns (PFGE) of XbaI-digested chromosomal DNA. PFGE analysis together with in vitro conjugation experiments suggested that diversity of resistance phenotypes within a clone may be resulted from the acquisition and loss of R-plasmids in an untreated and a treated flock. The numbers of resistance phenotypes observed among fecal isolates increased during the growth of the chickens in all the farms. The results in the present study suggest that persistence of commensal E. coli strains resistant to antimicrobials even in the absence of antimicrobial administration. It is also hypothesized that horizontal transmission of resistance determinants resulted in the emergence of different resistance phenotypes in those farms. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Virulence factors and genetic variability of uropathogenic Escherichia coli isolated from dogs and cats in Italy.

    PubMed

    Tramuta, Clara; Nucera, Daniele; Robino, Patrizia; Salvarani, Sara; Nebbia, Patrizia

    2011-03-01

    In this study, the association between virulence genotypes and phylogenetic groups among Escherichia (E.) coli isolates obtained from pet dogs and cats with cystitis was detected, and fingerprinting methods were used to explore the relationship among strains. Forty uropathogenic E. coli (UPEC) isolated from dogs (n = 30) and cats (n = 10) in Italy were analysed by polymerase chain reaction (PCR) for the presence of virulence factors and their classification into phylogenetic groups. The same strains were characterized by repetitive extragenic palindromic (REP)- and enterobacterial repetitive intergenic consensus (ERIC)-PCR techniques. We found a high number of virulence factors such as fimbriae A, S fimbriae (sfa) and cytotoxic necrotizing factor 1 (cnf1) significantly associated with phylogenetic group B2. We demonstrated a high correlation between α-hemolysin A and pyelonephritis C, sfa, and cnf1 operons, confirming the presence of pathogenicity islands in these strains. In addition, UPEC belonging to group B2 harboured a greater number of virulence factors than strains from phylogenetic groups A, B1, and D. REP- and ERIC-PCR grouped the UPEC isolates into two major clusters, the former grouping E. coli strains belonging to phylogenetic group B2 and D, the latter grouping those belonging to groups A and B1. Given the significant genetic variability among the UPEC strains found in our study, it can be hypothesized that no specific genotype is responsible for cystitis in cats or dogs.

  5. Temporal changes in resistance mechanisms in colonizing Escherichia coli isolates with reduced susceptibility to fluoroquinolones.

    PubMed

    Han, Jennifer H; Nachamkin, Irving; Tolomeo, Pam; Mao, Xiangqun; Bilker, Warren B; Lautenbach, Ebbing

    2013-08-01

    The objective of this study was to characterize the temporal variability of fluoroquinolone resistance mechanisms among Escherichia coli colonizing the gastrointestinal tract of hospitalized patients. Patients with new fluoroquinolone-resistant E. coli (FQREC) colonization were followed with serial fecal sampling until discharge or death. Genetic mechanism(s) of resistance for all FQREC isolates was characterized, including mutations in gyrA and parC and efflux pump overexpression. Of 451 subjects, 73 (16.2%) became newly colonized with FQREC. There was significant variability in regard to temporal changes in resistance mechanisms and levofloxacin MICs among isolates from individual patients. Compared to patients with transient colonization, patients with persistent colonization were more likely to have a urinary catheter (P = 0.04), diarrhea (P = 0.04), and a longer duration of hospitalization (22 and 9.0 mean days, respectively; P = 0.01) prior to sampling. Our data demonstrate the significant variability of resistance mechanisms in colonizing E. coli isolates among hospitalized patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Temporal Changes in Resistance Mechanisms in Colonizing Escherichia coli Isolates with Reduced Susceptibility to Fluoroquinolones

    PubMed Central

    Han, Jennifer H.; Nachamkin, Irving; Tolomeo, Pam; Mao, Xiangqun; Bilker, Warren B.; Lautenbach, Ebbing

    2013-01-01

    The objective of this study was to characterize the temporal variability of fluoroquinolone resistance mechanisms among Escherichia coli colonizing the gastrointestinal tract of hospitalized patients. Patients with new fluoroquinolone-resistant E. coli (FQREC) colonization were followed with serial fecal sampling until discharge or death. Genetic mechanism(s) of resistance for all FQREC isolates were characterized, including mutations in gyrA and parC and efflux pump overexpression. Of 451 subjects, 73 (16.2%) became newly colonized with FQREC. There was significant variability in regard to temporal changes in resistance mechanisms and levofloxacin MICs among isolates from individual patients. Compared to patients with transient colonization, patients with persistent colonization were more likely to have a urinary catheter (P=0.04), diarrhea (P=0.04), and a longer duration of hospitalization (22 and 9.0 mean days, respectively; P=0.01) prior to sampling. Our data demonstrate the significant variability of resistance mechanisms in colonizing E. coli isolates among hospitalized patients. PMID:23719087

  7. Colistin resistance in Salmonella and Escherichia coli isolates from a pig farm in Great Britain.

    PubMed

    Anjum, Muna F; Duggett, Nicholas A; AbuOun, Manal; Randall, Luke; Nunez-Garcia, Javier; Ellis, Richard J; Rogers, Jon; Horton, Robert; Brena, Camilla; Williamson, Susanna; Martelli, Francesca; Davies, Robert; Teale, Christopher

    2016-08-01

    The objective of this study was to characterize colistin-resistant bacteria isolated from pigs on a farm in Great Britain following identification of a plasmid-borne colistin resistance mechanism in Escherichia coli from China. Phenotypic antimicrobial susceptibility testing was undertaken by broth dilution and WGS was performed to detect the presence of genes encoding resistance and virulence. Transferable colistin resistance was investigated by conjugation. Two E. coli and one Salmonella Typhimurium variant Copenhagen were shown to be MDR, including resistance to colistin, with one E. coli and the Salmonella carrying the mcr-1 gene; all three harboured chromosomal mutations in genes conferring colistin resistance and both E. coli harboured β-lactamase resistance. The Salmonella mcr-1 plasmid was highly similar to pHNSHP45, from China, while the E. coli mcr-1 plasmid only had the ISApII and mcr-1 genes in common. The frequency of mcr-1 plasmid transfer by conjugation to recipient Enterobacteriaceae from Salmonella was low, lying between 10(-7) and 10(-9) cfu/recipient cfu. We were unable to demonstrate mcr-1 plasmid transfer from the E. coli. Plasmid profiling indicated transfer of multiple plasmids from the Salmonella resulting in some MDR transconjugants. Identification of the mcr-1 gene in Enterobacteriaceae from pigs confirms its presence in livestock in Great Britain. The results suggest dissemination of resistance through different horizontally transferable elements. The in vitro transfer of multiple plasmids carrying colistin and other resistances from the Salmonella isolate underlines the potential for wider dissemination and recombination. © Crown copyright 2016.

  8. The effect of heat stress on the antibacterial resistance and plasmid profile in Escherichia coli isolates.

    PubMed

    Ahmadi, M; Ayremlou, N; Sale, H Dastmalchi

    2007-12-01

    In order to study the effect of heat stress on the antibacterial resistance and plasmid profile in Escherichia coli, thirty E. coli were isolated from sheep liver. Antibiotic susceptibility test were done by antibiotic disc diffusion method using filter paper disc on two 24 h cultures of each isolate which grown at 37 and 43 degrees C simultaneously in BHI Broth (Merck VM460193 531). The isolates which grown at 43 degrees C were under heat stress during their growth. Ten commonly used antibiotics, viz., ampicillin, erythromycin, neomycin, trimethoprim-sulfamethoxazol, lincospectine, tetracycline, gentamycin, flumequine, vancomycin and Tiamulin (Padtan Teb). The resistance level of all E. coli isolates against 10 antibacterial drugs compared statistically in 37 and 43 degrees C using MINITAB Version 14 program. Plasmid DNAs were extracted from each of the E. coli isolates which were grown at 37 and 43 degrees C overnight using alkali lysis method. In this study *lambdaDNA (EcoR1+Hind III digested) was used as marker DNA. According to the results of this study, the resistance rate of E. coli isolates have decreased against trimethoprim-sulfamethazol, lincospectine, tiamaulin, tetracyclin and gentamycin at 43 degrees C but only the difference between the resistance rate against gentamycin in 37 degrees C (83.3%) and 43 degrees C (60%) was significant Characterization of Plasmid DNAs by agarose gel electrophoresis showed that each of the thirty drug resistant E. coli harbored a single plasmid. There was no difference among the plasmid profiles of the thirty isolates in 37 and 43 degrees C. As the plasmid profile did not change in 43 degrees C (heat stress) so the resistance differences against antibacterial drugs were not significant except for gentamycine that its resistance may is chromosomal. According to the results of this study, In conclusion it can be said that heat stress could not be effective on antibacterial resistance and plasmid profile if the duration of

  9. 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. ...

  10. Genome Sequences of Five Multidrug-Resistant Escherichia coli Sequence Type 117 Isolates Recovered from Dairy Calves.

    PubMed

    Kim, Seon-Woo; Karns, Jeffrey S; Van Kessel, Jo Ann S; Haley, Bradd J

    2017-08-17

    Escherichia coli sequence type 117 (ST117) strains have been recovered from poultry with colibacillosis, as well as from urinary tract infections and fatal septic infections in humans. To further investigate ST117 isolates recovered from nonpoultry food animals, we sequenced the genomes of five ST117 isolates from dairy calves in Pennsylvania.

  11. Genome Sequences of Five Multidrug-Resistant Escherichia coli Sequence Type 117 Isolates Recovered from Dairy Calves

    PubMed Central

    Kim, Seon-Woo; Karns, Jeffrey S.; Van Kessel, Jo Ann S.

    2017-01-01

    ABSTRACT Escherichia coli sequence type 117 (ST117) strains have been recovered from poultry with colibacillosis, as well as from urinary tract infections and fatal septic infections in humans. To further investigate ST117 isolates recovered from nonpoultry food animals, we sequenced the genomes of five ST117 isolates from dairy calves in Pennsylvania. PMID:28818889

  12. Virulence Factors and Phenotypical Traits of Verotoxin-Producing Escherichia coli Strains Isolated from Asymptomatic Human Carriers

    PubMed Central

    Stephan, R.; Untermann, F.

    1999-01-01

    Fourteen verotoxin-producing Escherichia coli strains isolated from stool samples of 14 different asymptomatic human carriers were further characterized. A variety of serotypes was found, but none of the strains belonged to serogroup O157. Only one isolate carried most of the virulence genes that are associated with increased pathogenicity. PMID:10203524

  13. Escherichia coli isolates from sick chickens in China: changes in antimicrobial resistance between 1993 and 2013.

    PubMed

    Chen, Xiang; Zhang, Weiqiu; Yin, Jiajun; Zhang, Ning; Geng, Shizhong; Zhou, Xiaohui; Wang, Yanhong; Gao, Song; Jiao, Xinan

    2014-10-01

    The use of antimicrobials for the control of infectious disease has increased in recent decades. Understanding trends in antimicrobial resistance provides clues about the relationship between antimicrobial use and the emergence of resistance. We examined the resistance of 540 Escherichia coli isolates to 19 antimicrobials that represent 11 classes of antimicrobial agents. The isolates were collected from chickens between 1993 and 2013 in China. Overall, >96.7% of the isolates were resistant to at least one of the tested compounds, and 87.2% of them displayed multidrug resistance (MDR) representing five to six antimicrobial classes. A high proportion of E. coli isolates were resistant to tetracycline (90.6%), nalidixic acid (80.6%), ampicillin (77.2%), trimethoprim-sulfamethoxazole (76.9%), and streptomycin (72.8%). Only 3.0% of the isolates were resistant to nitrofurantoin, and none was resistant to meropenem. Resistance to amikacin, ampicillin, aztreonam, ceftazidime, cefotaxime, cephalothin, chloramphenicol, ciprofloxacin, fosfomycin, levofloxacin, norfloxacin, nalidixic acid, piperacillin, and trimethoprim-sulfamethoxazole significantly increased from 1993 to 2013 (P <0.01). There was an increasing trend in MDR over the 20 year period. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Serotypes, virulence genes, and PFGE patterns of enteropathogenic Escherichia coli isolated from Cuban pigs with diarrhea.

    PubMed

    Blanco, Miguel; Lazo, Leonel; Blanco, Jesús E; Dahbi, Ghizlane; Mora, Azucena; López, Cecilia; González, Enrique A; Blanco, Jorge

    2006-03-01

    Thirty-six enteropathogenic Escherichia coli strains isolated from Cuban pigs with diarrhea were serotyped and screened by PCR for the presence of virulence genes. The 36 isolates belonged to 11 O serogroups and 14 O:H serotypes, with 53% of the isolates belonging to only two serotypes: O141:H- (13 isolates) and O157:H19 (6 isolates). Genes coding for STb, STa, VT2e, and LT toxins were identified in 69, 61, 53, and 6% of the isolates, respectively. The most prevalent fimbrial adhesin was F18, detected in 22 (61%) isolates. The gene encoding F6 (P987) colonization factor was identified in three (8%) isolates. None of the 36 isolates assayed contained genes encoding F4 (K88), F5 (K99), or F41. The seropathotype O141:H-:STa/STb/VT2e/F18 (13 isolates) was the most frequently detected, followed by O157:H19:VT2e/F18 (5 isolates). A genetic diversity study, carried out by pulsed-field gel electrophoresis (PFGE) of 24 representative isolates, revealed 21 distinct restriction patterns clustered in 18 groups (I-XVIII). Isolates of the same serotype were placed together in a dendrogram, but isolates of serotype O157:H19 showed a high degree of polymorphism. The results of this study demonstrate the presence in Cuba of different clusters among one of the most prevalent serotypes isolated from pigs with diarrhea. Further experiments are needed to determine whether some of these clusters have appeared recently; if so, their evolution, as well as their possible association with pathogenicity in farms should be studied.

  15. Escherichia coli strain diversity: Selecting isolates for use as pathogen surrogates

    USDA-ARS?s Scientific Manuscript database

    Background Escherichia coli (E. coli) is commonly used as a surrogate for pathogens in research to identify sources of agricultural contamination and to characterize how pathogens persist on plant surfaces. However, E. coli strains are highly diverse, exhibiting differences in physical, chemical and...

  16. β-Lactamases in Ampicillin-Resistant Escherichia coli Isolates from Foods, Humans, and Healthy Animals

    PubMed Central

    Briñas, Laura; Zarazaga, Myriam; Sáenz, Yolanda; Ruiz-Larrea, Fernanda; Torres, Carmen

    2002-01-01

    TEM-, SHV-, and OXA-type β-lactamases were studied by PCR with 124 ampicillin-resistant (AMPr) Escherichia coli isolates recovered from foods of animal origin (n = 20) and feces of humans (n = 49) and healthy animals (n = 55). PCR showed that 103 isolates were positive for TEM and negative for SHV and OXA. Three E. coli isolates showed a positive reaction for OXA, and one showed a positive reaction for SHV. The remaining 17 E. coli isolates were negative for the three enzymes by PCR. Fifty-seven of the 103 blaTEM amplicons were sequenced. Different molecular variants of blaTEM-1 were found in 52 isolates: blaTEM-1a (n = 9), blaTEM-1b (n = 36), blaTEM-1c (n = 6), and blaTEM-1f (n = 1). Four inhibitor-resistant TEM (IRT) β-lactamase-encoding genes were also detected: blaTEM-30c (IRT-2), blaTEM-34b (IRT-6), blaTEM-40b (IRT-11), and blaTEM-51a (IRT-15). A new blaTEM gene, named blaTEM-95b, which showed a mutation in amino acid 145 (P→A) was detected. It was found in a food isolate of chicken origin (AMPr, amoxicillin-clavulanic acid susceptible). The promoter region in 24 blaTEM amplicons was analyzed, and the weak P3 promoter was found in 23 of them (blaTEM-1 in 20 amplicons and blaTEM-51a, blaTEM-30c, and blaTEM-95b in 1 amplicon each). The strong Pa/Pb promoter was found only in the blaTEM-34b gene. No extended-spectrum β-lactamases were detected. Mutations at position −42 or −32 in the ampC gene promoter were demonstrated in 4 of 10 E. coli isolates for which the cefoxitin MIC was ≥16 μg/ml. Different variants of blaTEM-1 and IRT blaTEM genes were found among the AMPr E. coli isolates from foods and the feces of humans and healthy animals, and a new gene, blaTEM-95b (P3), was detected. PMID:12234838

  17. Mechanisms of cephalosporin resistance in indicator Escherichia coli isolated from food animals.

    PubMed

    Lalak, Anna; Wasyl, Dariusz; Zając, Magdalena; Skarżyńska, Magdalena; Hoszowski, Andrzej; Samcik, Ilona; Woźniakowski, Grzegorz; Szulowski, Krzysztof

    2016-10-15

    Resistance to β-lactams is considered one of the major global problems and recently it became the most frequently studied topic in the area of antimicrobial resistance. The study was focused on phenotypic and genetic characterisation of commensal Escherichia coli (E. coli), including those producing cephalosporinases, isolated from gut flora of healthy slaughter animals. E. coli were cultured simultaneously on MacConkey agar (MCA) and cefotaxime supplemented MCA. The isolates were confirmed with ONPG and indol tube tests as well as PCR targeting uspA gene. Microbroth dilution method was applied for determination of Minimal Inhibitory Concentrations and interpreted according to EUCAST epidemiological cut-off values. Cephalosporin resistance phenotypes were defined by E-tests (BioMerieux) and relevant gene amplicons from selected strains were sequenced. A total of 298 E. coli isolates with cephalosporin resistance (ESC) found in 99 ones, were obtained from 318 cloacal or rectal swabs deriving from broilers, layers, turkeys, pigs and cattle. Both extended spectrum β-lactamase (ESBL) and ampC-cephalosporinase resistance phenotypes were noted in all tested animal species but cattle. At least one of the analysed genes was identified in 90 out of 99 cephalosporin-resistant isolates: blaTEM (n=44), blaCMY (n=38), blaCTX-M (n=33) and blaSHV (n=12). None of the phenotypes was identified in nine isolates. Sequencing of PCR products showed occurrence of ESBL-genes: blaCTX-M-1/-61, blaSHV-12, blaTEM-1,-52/-92,-135 and ampC-gene blaCMY-2. They were located on numerous and diverse plasmids and resistance transferability was proved by electroporation of blaSHV-12 and blaCTX-M-1/-61 located on X1 plasmids. Detection of cephalosporin resistant E. coli confirms the existence of resistance genes reservoir in farm animals and their possible spread (i.e. via IncX1 plasmids) to other bacteria including human and animal pathogens. The identified genetic background indicates on

  18. Mechanisms of fluoroquinolone resistance in Escherichia coli isolates from food-producing animals.

    PubMed

    Karczmarczyk, Maria; Martins, Marta; Quinn, Teresa; Leonard, Nola; Fanning, Séamus

    2011-10-01

    Eleven multidrug-resistant Escherichia coli isolates (comprising 6 porcine and 5 bovine field isolates) displaying fluoroquinolone (FQ) resistance were selected from a collection obtained from the University Veterinary Hospital (Dublin, Ireland). MICs of nalidixic acid and ciprofloxacin were determined by Etest. All showed MICs of nalidixic acid of >256 μg/ml and MICs of ciprofloxacin ranging from 4 to >32 μg/ml. DNA sequencing was used to identify mutations within the quinolone resistance-determining regions of target genes, and quantitative real-time PCR (qRT-PCR) was used to evaluate the expression of the major porin, OmpF, and component genes of the AcrAB-TolC efflux pump and its associated regulatory loci. Decreased MIC values to nalidixic acid and/or ciprofloxacin were observed in the presence of the efflux pump inhibitor phenylalanine-arginine-β-naphthylamide (PAβN) in some but not all isolates. Several mutations were identified in genes coding for quinolone target enzymes (3 to 5 mutations per strain). All isolates harbored GyrA amino acid substitutions at positions 83 and 87. Novel GyrA (Asp87 → Ala), ParC (Ser80 → Trp), and ParE (Glu460 → Val) substitutions were observed. The efflux activity of these isolates was evaluated using a semiautomated ethidium bromide (EB) uptake assay. Compared to wild-type E. coli K-12 AG100, isolates accumulated less EB, and in the presence of PAβN the accumulation of EB increased. Upregulation of the acrB gene, encoding the pump component of the AcrAB-TolC efflux pump, was observed in 5 of 11 isolates, while 10 isolates showed decreased expression of OmpF. This study identified multiple mechanisms that likely contribute to resistance to quinolone-based drugs in the field isolates studied.

  19. 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

  20. Prevalence and antibiogram profiling of Escherichia coli pathotypes isolated from the Kat River and the Fort Beaufort abstraction water.

    PubMed

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

    2014-08-12

    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.

  1. 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 stx2a, stx2c, and stx2d 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.

  2. Bactericidal activity of Musca domestica cecropin (Mdc) on multidrug-resistant clinical isolate of Escherichia coli.

    PubMed

    Lu, X; Shen, J; Jin, X; Ma, Y; Huang, Y; Mei, H; Chu, F; Zhu, J

    2012-08-01

    The housefly (Musca domestica) larvae have been used clinically to cure osteomyelitis, decubital necrosis, lip boil, ecthyma and malnutritional stagnation ever since the Ming/Qing Dynasty (1368 Anno Domini) till now, in China. In prior research, we have cloned and characterized a new gene of antimicrobial peptide cecropin from M. domestica larvae. This peptide was potently active against Gram-positive and Gram-negative bacteria standard strain. In the present study, we evaluated the possibility of Mdc to be a potential bactericidal agent against clinical isolates of multidrug-resistant (MDR) Escherichia coli and to elucidate the related antimicrobial mechanisms. Antimicrobial activity assays indicated a minimal inhibitory concentration (MIC) of 1.56 μM. Bactericidal kinetics at MIC showed that Mdc rapid killing of MDR E. coli. Lipopolysaccharide (LPS) dose-dependently suppressed Mdc antibacterial potency indicates that LPS is the initial binding site of Mdc in E. coli. Propidium iodide-based flow cytometry revealed that Mdc causes E. coli membrane permeabilization. Transmission electron micrographs further indicated that a remarkable damage in the bacteria's outer and inner membrane, even the leakage of cytoplasmic contents induced by Mdc. DNA binding experimental result implies that DNA is one of the possible intracellular targets of Mdc. Of note, Mdc did not show a perceptible cytotoxic effect on human red blood cells. Altogether, these results suggest that Mdc could be an excellent candidate for the development of more efficacious bactericidal agents.

  3. ppGpp and cytotoxicity diversity in Shiga toxin-producing Escherichia coli (STEC) isolates.

    PubMed

    Stella, A E; Luz Hessel DA Cunha, D; Piazza, R M F; Spira, B

    2017-08-01

    Shiga toxin-producing Escherichia coli (STEC) is a known food pathogen, which main reservoir is the intestine of ruminants. The abundance of different STEC lineages in nature reflect a heterogeneity that is characterised by the differential expression of certain genotypic characteristics, which in turn are influenced by the environmental conditions to which the microorganism is exposed. Bacterial homeostasis and stress response are under the control of the alarmone guanosine tetraphosphate (ppGpp), which intrinsic levels varies across the E. coli species. In the present study, 50 STEC isolates from healthy sheep were evaluated regarding their ppGpp content, cytotoxicity and other relevant genetic and phenotypic characteristics. We found that the level of ppGpp and cytotoxicity varied considerably among the examined strains. Isolates that harboured the stx2 gene were the least cytotoxic and presented the highest levels of ppGpp. All stx2 isolates belonged to phylogroup A, while strains that carried stx1 or both stx1 and stx2 genes pertained to phylogroup B1. All but two stx2 isolates belonged to the stx2b subtype. Strains that belonged to phylogroup B1 displayed on average low levels of ppGpp and high cytotoxicity. Overall, there was a negative correlation between cytotoxicity and ppGpp.

  4. Prevalence of tetracycline resistance determinants in broiler isolated Escherichia coli in Iran.

    PubMed

    Seifi, S; Khoshbakht, R

    2016-12-01

    1. Tetracycline resistance determinants are widespread among bacterial species. Resistance to tetracycline occurs by different mechanisms regulated by various genes. 2. The study was conducted to determine the tetracycline resistance and prevalence of tetracycline resistance determinants among Escherichia coli strains isolated from broilers in northern Iran. 3. Minimum inhibitory concentration (MIC) of tetracycline and susceptibility pattern of the isolates were screened using micro-dilution and disk diffusion methods, respectively. The presence of 7 tetracycline resistance genes including tetA, tetB, tetC, tetD, tetE, tetG and tetM was tested using the polymerase chain reaction. 4. Among 100 strains isolated from broilers, 73% were identified as tetracycline resistant. All isolates showed the presence of tetracycline-associated genes. The most prevalent genes were tetA (46%) and tetB (41%) and totally, 17 different genotypes were recognised according to the presence of tetracycline resistance genes. Statistical analysis revealed that concomitant presence of the resistance genes significantly increased the tetracycline MIC and effectiveness of phenotypic characterisation. 5. The results demonstrated a high occurrence of tetracycline-resistant E. coli and related genes among broilers which presents a risk of increasing these strains in human infections associated with food animals.

  5. Phylogenetic analysis of Escherichia coli isolated from broilers with colibacillosis based on gyrA gene sequences.

    PubMed

    Shamsi, Hamid; Mardani, Karim; Ownagh, Abdolghaffar

    2017-01-01

    Escherichia coli isolates from chickens with colibacillosis were assigned to phylogenetic groups based on multiplex polymerase chain reaction (PCR) and antibacterial resistance of E. coli belonging to these groups was examined. Furthermore, the gyrA gene of isolates was sequenced and a phylogenetic tree was generated. A total of 84 E. coli isolates were grouped using multiplex PCR of TSPE4.C2, chuA, yjaA, and gadA molecular markers. Four phylogenetic groups were identified with strains divided as follows: 16 in group A (19.05%), 17 in group B1 (20.24%), 23 in group B2 (27.38%), and 28 in group D (33.33%). Escherichia coli isolates belonging to phylogenetic groups B2 and D were resistant to Soltrim and Flumequine unlike the majority of E. coli isolates that belonged to groups A and B1, and which were susceptible to these antibiotics. The phylogenetic results based on gyrA gene sequences from multiplex PCR revealed that E. coli phylogenetic grouping was in accordance with the clusters obtained in the phylogenetic tree. In conclusion, the comparative sequence analysis of gyrA sequences provides a firm framework for an accurate classification of E. coli and related taxa and may constitute a pertinent phylogenetic marker for E. coli.

  6. Dairy Farm Age and Resistance to Antimicrobial Agents in Escherichia coli Isolated from Dairy Topsoil

    PubMed Central

    Jones, Suzanna E.; Burgos, Jonathan M.; Lutnesky, Marvin M.F.; Sena, Johnny A.; Kumar, Sanath; Jones, Lindsay M.; Varela, Manuel F.

    2010-01-01

    Antimicrobial agent usage is common in animal agriculture for therapeutic and prophylactic purposes. Selective pressure exerted by these antimicrobials on soil bacteria could result in the selection of strains that are resistant due to chromosomal or plasmid-derived genetic components. Multiple antimicrobial resistances in Escherichia coli and the direct relationship between antimicrobial agent use over time has been extensively studied, yet the relationship between the age of an animal agriculture environment such as a dairy farm and antibiotic resistance remains unclear. Therefore, we tested the hypothesis that antimicrobial resistance profiles of E. coli isolated from dairy farm topsoil correlate with dairy farm age. E. coli isolated from eleven dairy farms of varying ages within Roosevelt County, NM were used for MIC determinations to chloramphenicol, nalidixic acid, penicillin, tetracycline, ampicillin, amoxicillin/clavulanic acid, gentamicin, trimethoprim/sulfamethoxazole, cefotaxime and ciprofloxacin. The minimum inhibitory concentration values of four antibiotics ranged between 0.75 - >256 μg/ml, 1 - >256 μg/ml, 12 - >256 μg/ml, and 0.75 - >256 μg/ml for chloramphenicol, nalidixic acid, penicillin and tetracycline, respectively. The study did not show a direct relationship between antibiotic resistance and the age of dairy farms. PMID:21153729

  7. Dairy farm age and resistance to antimicrobial agents in Escherichia coli isolated from dairy topsoil.

    PubMed

    Jones, Suzanna E; Burgos, Jonathan M; Lutnesky, Marvin M F; Sena, Johnny A; Kumar, Sanath; Jones, Lindsay M; Varela, Manuel F

    2011-04-01

    Antimicrobial agent usage is common in animal agriculture for therapeutic and prophylactic purposes. Selective pressure exerted by these antimicrobials on soil bacteria could result in the selection of strains that are resistant due to chromosomal- or plasmid-derived genetic components. Multiple antimicrobial resistances in Escherichia coli and the direct relationship between antimicrobial agent use over time has been extensively studied, yet the relationship between the age of an animal agriculture environment such as a dairy farm and antibiotic resistance remains unclear. Therefore, we tested the hypothesis that antimicrobial-resistance profiles of E. coli isolated from dairy farm topsoil correlate with dairy farm age. E. coli isolated from eleven dairy farms of varying ages within Roosevelt County, NM were used for MIC determinations to chloramphenicol, nalidixic acid, penicillin, tetracycline, ampicillin, amoxicillin/clavulanic acid, gentamicin, trimethoprim/sulfamethoxazole, cefotaxime, and ciprofloxacin. The minimum inhibitory concentration values of four antibiotics ranged 0.75 to >256 μg/ml, 1 to >256 μg/ml, 12 to >256 μg/ml, and 0.75 to >256 μg/ml for chloramphenicol, nalidixic acid, penicillin, and tetracycline, respectively. The study did not show a direct relationship between antibiotic resistance and the age of dairy farms.

  8. Characterization of Vaginal Escherichia coli Isolated from Pregnant Women in Two Different African Sites

    PubMed Central

    Sáez-López, Emma; Cossa, Anélsio; Benmessaoud, Rachid; Madrid, Lola; Moraleda, Cinta; Villanueva, Sonia; Tligui, Houssain; Moiane, Benilde; Alami, Hassan; Massora, Sérgio; Bezad, Rachid; Mandomando, Inacio; Bosch, Jordi; Vila, Jordi; Bassat, Quique; Soto, Sara M.

    2016-01-01

    The relevance of vaginal colonization of pregnant women by Escherichia coli is poorly understood, despite these strains sharing a similar virulence profile with other extraintestinal pathogenic E. coli producing severe obstetric and neonatal infections. We characterized the epidemiology, antimicrobial susceptibility and virulence profiles of 84 vaginal E. coli isolates from pregnant women from Rabat (Morocco) and Manhiça (Mozambique), two very distinct epidemiological settings. Low levels of antimicrobial resistance were observed to all drugs tested, except for trimethoprim-sulfamethoxazole in Manhiça, where this drug is extensively used as prophylaxis for opportunistic HIV infections. The most prevalent virulence factors were related to iron acquisition systems. Phylogroup A was the most common in Rabat, while phylogroups E and non-typeable were the most frequent in Manhiça. Regardless of the apparently “low virulence” of these isolates, the frequency of infections is higher and the outcomes more devastating in constrained-resources conditions, especially among pregnant women and newborns. PMID:27387665

  9. 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.

  10. Surveillance of antimicrobial resistance in Escherichia coli strains isolated from pigs at Spanish slaughterhouses.

    PubMed

    Teshager, T; Herrero, I A; Porrero, M C; Garde, J; Moreno, M A; Domínguez, L

    2000-07-01

    Antimicrobial resistance can make the efficient treatment of bacterial infections in humans and animals more difficult. Antimicrobial use in food animals may be one of the factors contributing to resistance. The Spanish surveillance network VAV has established a baseline of antimicrobial resistance in Escherichia coli strains from healthy pigs. Minimum inhibitory concentration and patterns of resistance to antimicrobials used in animals and humans were determined for 205 faecal strains isolated in a sampling frame of four slaughterhouses in Spain from 220 pigs in 1998. Higher levels of resistance were seen against antimicrobial agents authorised for use in food animals especially tetracycline, sulphonamides, trimethoprim and amoxycillin. All isolates were susceptible to antimicrobials employed mainly in humans such as ceftazidime, cefotaxime, imipenem, aztreonam and amikacin.

  11. Antimicrobial resistance in Escherichia coli isolates from raccoons (Procyon lotor) in Southern Ontario, Canada.

    PubMed

    Jardine, Claire M; Janecko, Nicol; Allan, Mike; Boerlin, Patrick; Chalmers, Gabhan; Kozak, Gosia; McEwen, Scott A; Reid-Smith, Richard J

    2012-06-01

    We conducted a cross-sectional study to determine the prevalence of antimicrobial resistance (AMR) in fecal Escherichia coli isolates from raccoons (Procyon lotor) living in Ontario, Canada. From June to October 2007, we trapped raccoons in three areas: one primarily urban site around Niagara, one primarily rural site north of Guelph, and one at the Toronto Zoo. In addition, we conducted a longitudinal study at the Toronto Zoo site to investigate the temporal dynamics of fecal E. coli and AMR in raccoons. Reduced susceptibility to ≥1 antimicrobial agent was detected in E. coli isolates from 19% of 16 raccoons at the urban site, 17% of 29 raccoons from the rural site, and 42% of 130 samples collected from 59 raccoons at the zoo site. Raccoons from the zoo site were significantly more likely to shed E. coli with reduced susceptibility to ≥1 antimicrobial agent than animals from the rural site (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.17 to 12.09; P = 0.02). Resistance to expanded-spectrum cephalosporins (and the associated bla(CMY-2) gene) was detected in two animals from the zoo site and one animal from the rural site. Serotyping and pulsed-field gel electrophoresis analysis show that raccoons on the zoo grounds harbor a diverse assemblage of E. coli, with rapid bacterial turnover within individuals over time. Our study indicates that raccoons may shed resistant bacteria of public health significance and that raccoons have the potential to disseminate these bacteria throughout their environment.

  12. Antimicrobial Resistance in Escherichia coli Isolates from Raccoons (Procyon lotor) in Southern Ontario, Canada

    PubMed Central

    Janecko, Nicol; Allan, Mike; Boerlin, Patrick; Chalmers, Gabhan; Kozak, Gosia; McEwen, Scott A.; Reid-Smith, Richard J.

    2012-01-01

    We conducted a cross-sectional study to determine the prevalence of antimicrobial resistance (AMR) in fecal Escherichia coli isolates from raccoons (Procyon lotor) living in Ontario, Canada. From June to October 2007, we trapped raccoons in three areas: one primarily urban site around Niagara, one primarily rural site north of Guelph, and one at the Toronto Zoo. In addition, we conducted a longitudinal study at the Toronto Zoo site to investigate the temporal dynamics of fecal E. coli and AMR in raccoons. Reduced susceptibility to ≥1 antimicrobial agent was detected in E. coli isolates from 19% of 16 raccoons at the urban site, 17% of 29 raccoons from the rural site, and 42% of 130 samples collected from 59 raccoons at the zoo site. Raccoons from the zoo site were significantly more likely to shed E. coli with reduced susceptibility to ≥1 antimicrobial agent than animals from the rural site (odds ratio [OR], 3.41; 95% confidence interval [CI], 1.17 to 12.09; P = 0.02). Resistance to expanded-spectrum cephalosporins (and the associated blaCMY-2 gene) was detected in two animals from the zoo site and one animal from the rural site. Serotyping and pulsed-field gel electrophoresis analysis show that raccoons on the zoo grounds harbor a diverse assemblage of E. coli, with rapid bacterial turnover within individuals over time. Our study indicates that raccoons may shed resistant bacteria of public health significance and that raccoons have the potential to disseminate these bacteria throughout their environment. PMID:22447599

  13. Resistance of Escherichia coli urinary isolates in ED-treated patients from a community hospital.

    PubMed

    Fleming, Virginia H; White, Bryan P; Southwood, Robin

    2014-08-01

    The purpose of this study is to provide resistance data for Escherichia coli isolates causing urinary tract infections in emergency department (ED) patients not requiring admission and explore if differences between this subpopulation and the hospital antibiogram exist. Differences between community-acquired urinary tract infection (CA-UTI) and health care-associated (HA-UTI) subgroups were also investigated. Patients with a positive urine culture treated and discharged from the ED of a 200-bed community hospital were reviewed. Patients with urinary isolates of more than 100000 colony-forming unit/mL and documented intention to treat were included. Patients who required admission, were pregnant, less than the age of 18 years, or who had a positive culture but without any evidence of intention to treat were excluded. Only the initial visit was included for patients who returned to the ED within 7 days. Overall, 308 visits were screened, and 217 were included. Of these, 78.3% were CA-UTI, and 21.7% were HA-UTI. Females comprised 88.5% of all patients. E coli was the most common pathogen overall and in both subgroups. E coli resistance to levofloxacin was 13.5% overall, 9.2% for CA-UTI, and 38.5% for HA-UTI compared with 27% on the hospital antibiogram. E coli resistance to sulfamethoxazole/trimethoprim was 26.9% overall, 25.2% for CA-UTI, and 34.6% for HA-UTI vs 26% on the antibiogram. E coli susceptibility for ED patients not requiring admission may not be accurately represented by hospital antibiograms that contain culture data from various patient types, sites of infection, or patients with varying illness severity. Separation of the ED population into CA-UTI and HA-UTI subgroups may be helpful when selecting empiric antibiotic therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Genome Sequences of 30 Escherichia coli O157:H7 Isolates Recovered from a Single Dairy Farm and Its Associated Off-Site Heifer-Raising Facility.

    PubMed

    Kim, Seon-Woo; Karns, Jeffrey S; Van Kessel, Jo Ann S; Haley, Bradd J

    2017-08-31

    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-year period were sequenced.

  15. 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...

  16. Phenotypic and Genotypic Characterization of Enterotoxigenic Escherichia coli Clinical Isolates from Northern Colombia, South America

    PubMed Central

    Guerra, Julio A.; Romero-Herazo, Yesenia C.; Arzuza, Octavio; Gómez-Duarte, Oscar G.

    2014-01-01

    Enterotoxigenic Escherichia coli (ETEC) are major causes of childhood diarrhea in low and middle income countries including Colombia, South America. To understand the diversity of ETEC strains in the region, clinical isolates obtained from northern Colombia children were evaluated for multiple locus sequencing typing, serotyping, classical and nonclassical virulence genes, and antibiotic susceptibility. Among 40 ETEC clinical isolates evaluated, 21 (52.5%) were positive for LT gene, 13 (32.5%) for ST gene, and 6 (15%) for both ST and LT. The most prevalent colonization surface antigens (CS) were CS21 and CFA/I identified in 21 (50%) and 13 (32.5%) isolates, respectively. The eatA, irp2, and fyuA were the most common nonclassical virulence genes present in more than 60% of the isolates. Ampicillin resistance (80% of the strains) was the most frequent phenotype among ETEC strains followed by trimethoprim-sulfamethoxazole resistance (52.5%). Based on multiple locus sequencing typing (MLST), we recognize that 6 clonal groups of ETEC clinical isolates circulate in Colombia. ETEC clinical isolates from children in northern Colombia are highly diverse, yet some isolates circulating in the community belong to well-defined clonal groups that share a unique set of virulence factors, serotypes, and MLST sequence types. PMID:24877071

  17. Virulence traits and pathogenicity of uropathogenic Escherichia coli isolates with common and uncommon O serotypes.

    PubMed

    Gao, Qingqing; Zhang, Debao; Ye, Zhengqin; Zhu, Xiaoping; Yang, Weixia; Dong, Lanmei; Gao, Song; Liu, Xiufan

    2017-03-01

    Urinary tract infections (UTIs) are among the most common human diseases worldwide. This study aimed to collect uropathogenic Escherichia coli (UPEC) isolates from Jiangsu Province and obtain insights into the molecular epidemiology of UPEC in this region. The O serotypes, phylogenetic groups, and virulence factors of 183 UPEC isolates were determined. In this study, we isolated 51 UPEC isolates with common O serotypes including O1, O2, O4, O6, O7, O16, O18 and O75, as well as 35 of those with uncommonly encountered O serotypes including O8, O12, O15, O26, and O74. Groups B2 and D were the most prevalent phylogenetic groups and accounted for 29.5% and 41% of the isolates, respectively. In the tested 13 virulence genes (VGs), tonB and dsdA possessed the highest prevalence rate, followed by fimH, degP and ompR. Several other virulence genes such as fliC, neuC, ireA, and vat had prevalence less than 23%. Moreover, representative isolates belonging to common or uncommon O serotypes with different numbers of VGs were chosen for the pathogenic analyses. Based on the results of 1-day-old chick lethality assay and UTI ascending mouse infection model, our study suggested that the virulence of UPEC isolates for chicks and/or mice depended on both the number of VGs expressed and the O serotypes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Phenotypic and genotypic characterization of enterotoxigenic Escherichia coli clinical isolates from northern Colombia, South America.

    PubMed

    Guerra, Julio A; Romero-Herazo, Yesenia C; Arzuza, Octavio; Gómez-Duarte, Oscar G

    2014-01-01

    Enterotoxigenic Escherichia coli (ETEC) are major causes of childhood diarrhea in low and middle income countries including Colombia, South America. To understand the diversity of ETEC strains in the region, clinical isolates obtained from northern Colombia children were evaluated for multiple locus sequencing typing, serotyping, classical and nonclassical virulence genes, and antibiotic susceptibility. Among 40 ETEC clinical isolates evaluated, 21 (52.5%) were positive for LT gene, 13 (32.5%) for ST gene, and 6 (15%) for both ST and LT. The most prevalent colonization surface antigens (CS) were CS21 and CFA/I identified in 21 (50%) and 13 (32.5%) isolates, respectively. The eatA, irp2, and fyuA were the most common nonclassical virulence genes present in more than 60% of the isolates. Ampicillin resistance (80% of the strains) was the most frequent phenotype among ETEC strains followed by trimethoprim-sulfamethoxazole resistance (52.5%). Based on multiple locus sequencing typing (MLST), we recognize that 6 clonal groups of ETEC clinical isolates circulate in Colombia. ETEC clinical isolates from children in northern Colombia are highly diverse, yet some isolates circulating in the community belong to well-defined clonal groups that share a unique set of virulence factors, serotypes, and MLST sequence types.

  19. Escherichia coli bacteriocins: antimicrobial efficacy and prevalence among isolates from patients with bacteraemia.

    PubMed

    Budič, Maruška; Rijavec, Matija; Petkovšek, Ziva; Zgur-Bertok, Darja

    2011-01-01

    Bacteriocins are antimicrobial peptides generally active against bacteria closely related to the producer. Escherichia coli produces two types of bacteriocins, colicins and microcins. The in vitro efficacy of isolated colicins E1, E6, E7, K and M, was assessed against Escherichia coli strains from patients with bacteraemia of urinary tract origin. Colicin E7 was most effective, as only 13% of the tested strains were resistant. On the other hand, 32%, 33%, 43% and 53% of the tested strains exhibited resistance to colicins E6, K, M and E1. Moreover, the inhibitory activity of individual colicins E1, E6, E7, K and M and combinations of colicins K, M, E7 and E1, E6, E7, K, M were followed in liquid broth for 24 hours. Resistance against individual colicins developed after 9 hours of treatment. On the contrary, resistance development against the combined action of 5 colicins was not observed. One hundred and five E. coli strains from patients with bacteraemia were screened by PCR for the presence of 5 colicins and 7 microcins. Sixty-six percent of the strains encoded at least one bacteriocin, 43% one or more colicins, and 54% one or more microcins. Microcins were found to co-occur with toxins, siderophores, adhesins and with the Toll/Interleukin-1 receptor domain-containing protein involved in suppression of innate immunity, and were significantly more prevalent among strains from non-immunocompromised patients. In addition, microcins were highly prevalent among non-multidrug-resistant strains compared to multidrug-resistant strains. Our results indicate that microcins contribute to virulence of E. coli instigating bacteraemia of urinary tract origin.

  20. Molecular Profiling of Shiga Toxin-Producing Escherichia coli and Enteropathogenic E. coli Strains Isolated from French Coastal Environments

    PubMed Central

    Balière, C.; Rincé, A.; Delannoy, S.; Fach, P.

    2016-01-01

    ABSTRACT Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) strains may be responsible for food-borne infections in humans. Twenty-eight STEC and 75 EPEC strains previously isolated from French shellfish-harvesting areas and their watersheds and belonging to 68 distinguishable serotypes were characterized in this study. High-throughput real-time PCR was used to search for the presence of 75 E. coli virulence-associated gene targets, and genes encoding Shiga toxin (stx) and intimin (eae) were subtyped using PCR tests and DNA sequencing, respectively. The results showed a high level of diversity between strains, with 17 unique virulence gene profiles for STEC and 56 for EPEC. Seven STEC and 15 EPEC strains were found to display a large number or a particular combination of genetic markers of virulence and the presence of stx and/or eae variants, suggesting their potential pathogenicity for humans. Among these, an O26:H11 stx1a eae-β1 strain was associated with a large number of virulence-associated genes (n = 47), including genes carried on the locus of enterocyte effacement (LEE) or other pathogenicity islands, such as OI-122, OI-71, OI-43/48, OI-50, OI-57, and the high-pathogenicity island (HPI). One O91:H21 STEC strain containing 4 stx variants (stx1a, stx2a, stx2c, and stx2d) was found to possess genes associated with pathogenicity islands OI-122, OI-43/48, and OI-15. Among EPEC strains harboring a large number of virulence genes (n, 34 to 50), eight belonged to serotype O26:H11, O103:H2, O103:H25, O145:H28, O157:H7, or O153:H2. IMPORTANCE The species E. coli includes a wide variety of strains, some of which may be responsible for severe infections. This study, a molecular risk assessment study of E. coli strains isolated from the coastal environment, was conducted to evaluate the potential risk for shellfish consumers. This report describes the characterization of virulence gene profiles and stx/eae polymorphisms of E. coli

  1. Two novel CMY-2-type β-lactamases encountered in clinical Escherichia coli isolates.

    PubMed

    Manageiro, Vera; Ferreira, Eugénia; Pinto, Margarida; Fonseca, Fernando; Ferreira, Mónica; Bonnet, Richard; Caniça, Manuela

    2015-03-18

    Chromosomally encoded AmpC β-lactamases may be acquired by transmissible plasmids which consequently can disseminate into bacteria lacking or poorly expressing a chromosomal bla AmpC gene. Nowadays, these plasmid-mediated AmpC β-lactamases are found in different bacterial species, namely Enterobacteriaceae, which typically do not express these types of β-lactamase such as Klebsiella spp. or Escherichia coli. This study was performed to characterize two E. coli isolates collected in two different Portuguese hospitals, both carrying a novel CMY-2-type β-lactamase-encoding gene. Both isolates, INSRA1169 and INSRA3413, and their respective transformants, were non-susceptible to amoxicillin, amoxicillin plus clavulanic acid, cephalothin, cefoxitin, ceftazidime and cefotaxime, but susceptible to cefepime and imipenem, and presented evidence of synergy between cloxacilin and cefoxitin and/or ceftazidime. The genetic characterization of both isolates revealed the presence of bla CMY-46 and bla CMY-50 genes, respectively, and the following three resistance-encoding regions: a Citrobacter freundii chromosome-type structure encompassing a blc-sugE-bla CMY-2-type -ampR platform; a sul1-type class 1 integron with two antibiotic resistance gene cassettes (dfrA1 and aadA1); and a truncated mercury resistance operon. This study describes two new bla CMY-2-type genes in E. coli isolates, located within a C. freundii-derived fragment, which may suggest their mobilization through mobile genetic elements. The presence of the three different resistance regions in these isolates, with diverse genetic determinants of resistance and mobile elements, may further contribute to the emergence and spread of these genes, both at a chromosomal or/and plasmid level.

  2. Characterisation of novel mutations involved in quinolone resistance in Escherichia coli isolated from imported shrimp.

    PubMed

    Nawaz, Mohamed; Sung, Kidon; Kweon, Ohgew; Khan, Saeed; Nawaz, Samia; Steele, Roger

    2015-05-01

    Fifty-five nalidixic acid-resistant Escherichia coli strains were isolated from imported shrimp. Purified PCR amplicons of gyrA, gyrB, parC and parE from the template DNA of all isolates were sequenced and analysed for point mutations that confer resistance to nalidixic acid and ciprofloxacin. Point mutations in the quinolone resistance-determining regions (QRDRs) of GyrA at positions 68, 83 and 87 and in ParC at positions 80 and 84 as well as in the non-QRDR of GyrA at positions 112, 127, 128 and 154 along with point mutations in parE at position 476 conferred resistance to these antibiotics. Computational modelling and analysis of the different point mutations and their role in the enhanced resistance to these antibiotics indicated that only mutation at codons 83 (Ser→Ile) and 87 (Asp→Asn) played a vital role in increasing the minimum inhibitory concentration (MIC) to these drugs compared with other mutations. Ethidium bromide experiments indicated higher efflux pump activities in quinolone-resistant E. coli strains compared with their quinolone-sensitive counterparts. Class 1 integrons measuring 0.7-2.3kb were amplified and sequenced from the template DNA of the isolates. Sequence analysis of the 2.0kb and 1.7kb integrons indicated the presence of resistance determinants for trimethoprim (dfrA12 and dfrA17) and aminoglycosides (aadA2 and aadA5). These results indicate that use of nalidixic acid, ciprofloxacin and other antibiotics in shrimp aquaculture ponds may select E. coli resistant to these antibiotics and that imported shrimp is a reservoir of multiple antibiotic-resistant E. coli.

  3. Investigating the Relatedness of Enteroinvasive Escherichia coli to Other E. coli and Shigella Isolates by Using Comparative Genomics.

    PubMed

    Hazen, Tracy H; Leonard, Susan R; Lampel, Keith A; Lacher, David W; Maurelli, Anthony T; Rasko, David A

    2016-08-01

    Enteroinvasive Escherichia coli (EIEC) is a unique pathovar that has a pathogenic mechanism nearly indistinguishable from that of Shigella species. In contrast to isolates of the four Shigella species, which are widespread and can be frequent causes of human illness, EIEC causes far fewer reported illnesses each year. In this study, we analyzed the genome sequences of 20 EIEC isolates, including 14 first described in this study. Phylogenomic analysis of the EIEC genomes demonstrated that 17 of the isolates are present in three distinct lineages that contained only EIEC genomes, compared to reference genomes from each of the E. coli pathovars and Shigella species. Comparative genomic analysis identified genes that were unique to each of the three identified EIEC lineages. While many of the EIEC lineage-specific genes have unknown functions, those with predicted functions included a colicin and putative proteins involved in transcriptional regulation or carbohydrate metabolism. In silico detection of the Shigella virulence plasmid (pINV), which is essential for the invasion of host cells, demonstrated that a form of pINV was present in nearly all EIEC genomes, but the Mxi-Spa-Ipa region of the plasmid that encodes the invasion-associated proteins was absent from several of the EIEC isolates. The comparative genomic findings in this study support the hypothesis that multiple EIEC lineages have evolved independently from multiple distinct lineages of E. coli via the acquisition of the Shigella virulence plasmid and, in some cases, the Shigella pathogenicity islands. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  4. Comparison of virulence gene profiles of Escherichia coli isolates from sows with coliform mastitis and healthy sows.

    PubMed

    Gerjets, Imke; Traulsen, Imke; Reiners, Kerstin; Kemper, Nicole

    2011-09-28

    Coliform mastitis (CM) is not only a serious economical and animal welfare touching problem in dairy cattle, but also in sows after farrowing. Due to this disease, the essential adequate supply with colostrum for the growth and the health of the piglets is not ensured. Besides other influencing factors, Escherichia (E.) coli is of great importance as a causative agent of this multifactorial disease. In this study, E. coli isolates from milk samples of healthy and CM-affected sows were examined for the presence of virulence genes associated with extraintestinal E. coli strains, enterotoxigenic E. coli and other pathogenic E. coli. The isolated E. coli harbored mainly virulence genes of extraintestinal E. coli strains (especially fimC, ompA, traT, hra, kpsMTII, iroN). The virulence gene spectrum for both samples from CM-affected and healthy sows did not differ significantly. Particular virulence gene profiles of E. coli isolates from diseased sows were not detected. This study provides novel insights into the role of E. coli in association with mastitis in sows since it is the first time E. coli isolates from CM-affected sows' milk were analysed for virulence genes. Because there were no differences in the prevalence of E. coli and their virulence-associated genes between healthy and diseased sows, other causative factors seem to have greater influence on the pathogenesis of porcine CM. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Prevalence and characteristics of lactose non-fermenting Escherichia coli in urinary isolates.

    PubMed

    Chang, Jiyoung; Yu, Jinkyung; Lee, Hyeyoung; Ryu, Hyejin; Park, Kanggyun; Park, Yeon-Joon

    2014-11-01

    Recently, serotype O75 was found to be prominent among the non-ST131 ciprofloxacin-resistant Escherichia coli, and they were all lactose non-fermenters. In this study, we investigated the prevalence and characteristics of lactose non-fermenters in urinary isolates of E. coli. A total of 167 E. coli isolates was collected. Antimicrobial susceptibility tests were determined by VITEK 2 (bioMerieux, France). The lactose non-fermenters underwent PCR-based O typing, multilocus sequence typing (MLST) analysis, phylogenetic grouping. For ciprofloxacin-resistant isolates, the resistance mechanisms were investigated. Thirty-three (19.7%) isolates were lactose non-fermenters and the ciprofloxacin resistance rate was significantly higher than in lactose fermenters (66.7% vs. 31.6%, P = 0.0002). According to the serotype, O75 was the most common (42.4%, 14/33) and was followed by O16 (5/33), O2 (4/33), O25b (3/33), O15 (1/33), O6 (1/33), O1 (1/33). All the O75 isolates were ciprofloxacin-resistant and belonged to ST1193. By MLST, they were resolved into 11 STs. ST1193 was the most common (14/33) and was followed by ST131 (8/33). Interestingly, 8 isolates of ST131 were divided into three O types [O16 (4 isolates), O25b (3), and non-typeable (1)]. The ciprofloxacin resistance rate was high in isolates of O75-ST1193 and O25b-ST131 but low in O16-ST131 and O2-ST95. All the ciprofloxacin-resistant isolates showed identical triple mutations in gyrA and parC but the serotype O25b isolates had an additional mutation in parC (E84V). Only one isolate harbored aac(6')-Ib-cr variant and no qnr gene was detected. Continuous monitoring of the prevalence and clonal composition of the lactose non-fermenters is needed.

  6. Antimicrobial susceptibility of Escherichia coli isolated from shrimp (Litopenaeus vannamei) and pond environment in northeastern Brazil.

    PubMed

    Vieira, Regine H S Dos F; Carvalho, Edirsana M R; Carvalho, Fatima C T; Silva, Camila M; Sousa, Oscarina V; Rodrigues, Dalia P

    2010-04-01

    This study aimed to test the susceptibility of Escherichia coli strains isolated from the water, bottom sediments and individuals cultivated in shrimp farm ponds, to antibiotics belonging to different families, namely B-Lactams: Imipenem (IPM; 10 micro g), Ampicillin (AMP; 10 micro g), Cephalothin (CEP; 30 micro g), Cefoxitin (FOX; 30 micro g), Ceftriaxone (CRO; 30 micro g); Tetracycline: Tetracycline (TCY; 30 micro g); Aminoglycosides: Gentamicin (GEN; 10 micro g), Amikacin (AMK; 30 micro g); Chloramphenicol: Chloramphenicol (CHO; 30 micro g); Fluoroquinolones: Ciprofloxacin (CIP; 5 micro g); Nitrofurans: Nitrofurantoin (NIT; 300 micro g); Sulfonamides: Trimethoprim-Sulfamethoxazole (SXT; 30 micro g); Quilononas: Nalidixic Acid (NAL; 30 micro g). In the laboratory, the method of dissemination (Test Kirby-Bauer) was performed in order to fulfill the antibiogram tests. The results showed high indices of resistance to Imipenem, Cephalothin and Ampicillin. Chloramphenicol, Nitrofurantoin, Cefoxitin, Ceftiaxone and Ciprofloxacin have displayed the highest index of sensitive strains. The antibiotic resistance index (ARI) and the multiple resistance index (MAR) varied within the ranges of 0.068-0.077 and 0.15-0.39, respectively. More than 90.5% of strains of Escherichia coli showed a variety of resistance profiles to the tested antibiotics. The high indices of resistance may be a consequence of indiscriminate use of antibiotics, but also the transfer of resistance through mobile genetic elements found in shrimp farms.

  7. Isolation and molecular characterization of Escherichia coli O157 isolated from cattle, pigs and chickens at slaughter.

    PubMed

    Tutenel, A V; Pierard, D; Van Hoof, J; Cornelis, M; De Zutter, L

    2003-07-15

    From 1999 until 2001, 3625 food samples were examined for the presence of Escherichia coli O157. Samples were from bovine origin (ground beef, n=549; carcasses, n=2452), calves (carcasses, n=147), chicken (breast, n=203; carcasses, n=71) and pigs (carcasses, n=85; trimmings, n=118). Vidas ECO detected 451 (12%) samples positive, but from only 27 (0.74%) samples was E. coli O157 isolated. One strain was isolated from bovine ground beef (0.18%), one from a pig carcass (1.17%) and all others were isolated from bovine carcasses (1.02%). All strains possessed the attaching-and-effacing gene, the enterohemorrhagic plasmid and verotoxin (VT) genes, except the strain isolated from the pig carcass that was therefore eliminated. Six of the strains were urease-positive. Strains were typed by two DNA fingerprinting methods: random amplification of polymorphic DNA (RAPD) and pulsed field gel electrophoresis (PFGE). PFGE revealed a similarity of 71.05%, while RAPD was 77.36% similar. None of the typing methods were able to classify all urease-positive strains to one pattern. Strains in the same PFGE cluster did not belong to one RAPD cluster. This paper highlights that Belgian fresh meat at retail level can be contaminated with E. coli O157 and that two different typing methods divide strains into different types.

  8. Phenotypical characterization and adhesin identification in Escherichia coli strains isolated from dogs with urinary tract infections

    PubMed Central

    Maluta, Renato Pariz; Stella, Ariel Eurides; Riccardi, Kátia; Rigobelo, Everlon Cid; Marin, José Moacir; Carvalho, Marileda Bonafim; de Ávila, Fernando Antonio

    2012-01-01

    Pathogenic strains of Escherichia coli are the most common bacteria associated with urinary tract infections in both humans and companion animals. Standard biochemical tests may be useful in demonstrating detailed phenotypical characteristics of these strains. Thirteen strains of E. coli isolated from dogs with UTIs were submitted to biochemical tests, serotyping for O and H antigens and antimicrobial resistance testing. Furthermore, the presence of papC, sfa, and afa genes was evaluated by PCR, and genetic relationships were established using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). The antimicrobial that showed the highest resistance rate among the isolates was nalidixic acid (76.9%), followed by cephalotin (69.2%), sulfamethoxazole + trimethoprim (61.5%), tetracycline (61.5%), streptomycin (53.8%), ciprofloxacin (53.8%), ampicillin (46.2%), gentamicin (30.8%) and chloramphenicol (23.1%). No isolate was resistant either to meropenem or nitrofurantoin. Among the five clusters that were identified using ERIC-PCR, one cluster (A) had only one strain, which belonged to a serotype with zoonotic potential (O6:H31) and showed the genes papC+, sfa+, afa-. Strains with the genes papC-, sfa+, afa- were found in two other clusters (C and D), whereas all strains in clusters B and E possessed papC-, sfa-, afa- genes. Sucrose and raffinose phenotypic tests showed some ability in discriminating clusters A, B and C from clusters D and E. PMID:24031842

  9. Mechanism of Reduced Susceptibility to Fosfomycin in Escherichia coli Clinical Isolates

    PubMed Central

    Ohkoshi, Yasuo; Sato, Toyotaka; Suzuki, Yuuki; Yamamoto, Soh; Shiraishi, Tsukasa; Ogasawara, Noriko

    2017-01-01

    In recent years, multidrug resistance of Escherichia coli has become a serious problem. However, resistance to fosfomycin (FOM) has been low. We screened E. coli clinical isolates with reduced susceptibility to FOM and characterized molecular mechanisms of resistance and reduced susceptibility of these strains. Ten strains showing reduced FOM susceptibility (MIC ≥ 8 μg/mL) in 211 clinical isolates were found and examined. Acquisition of genes encoding FOM-modifying enzyme genes (fos genes) and mutations in murA that underlie high resistance to FOM were not observed. We examined ability of FOM incorporation via glucose-6-phosphate (G6P) transporter and sn-glycerol-3-phosphate transporter. In ten strains, nine showed lack of growth on M9 minimum salt agar supplemented with G6P. Eight of the ten strains showed fluctuated induction by G6P of uhpT that encodes G6P transporter expression. Nucleotide sequences of the uhpT, uhpA, glpT, ptsI, and cyaA shared several deletions and amino acid mutations in the nine strains with lack of growth on G6P-supplemented M9 agar. In conclusion, reduction of uhpT function is largely responsible for the reduced sensitivity to FOM in clinical isolates that have not acquired FOM-modifying genes or mutations in murA. However, there are a few strains whose mechanisms of reduced susceptibility to FOM are still unclear. PMID:28197413

  10. Mechanism of Reduced Susceptibility to Fosfomycin in Escherichia coli Clinical Isolates.

    PubMed

    Ohkoshi, Yasuo; Sato, Toyotaka; Suzuki, Yuuki; Yamamoto, Soh; Shiraishi, Tsukasa; Ogasawara, Noriko; Yokota, Shin-Ichi

    2017-01-01

    In recent years, multidrug resistance of Escherichia coli has become a serious problem. However, resistance to fosfomycin (FOM) has been low. We screened E. coli clinical isolates with reduced susceptibility to FOM and characterized molecular mechanisms of resistance and reduced susceptibility of these strains. Ten strains showing reduced FOM susceptibility (MIC ≥ 8 μg/mL) in 211 clinical isolates were found and examined. Acquisition of genes encoding FOM-modifying enzyme genes (fos genes) and mutations in murA that underlie high resistance to FOM were not observed. We examined ability of FOM incorporation via glucose-6-phosphate (G6P) transporter and sn-glycerol-3-phosphate transporter. In ten strains, nine showed lack of growth on M9 minimum salt agar supplemented with G6P. Eight of the ten strains showed fluctuated induction by G6P of uhpT that encodes G6P transporter expression. Nucleotide sequences of the uhpT, uhpA, glpT, ptsI, and cyaA shared several deletions and amino acid mutations in the nine strains with lack of growth on G6P-supplemented M9 agar. In conclusion, reduction of uhpT function is largely responsible for the reduced sensitivity to FOM in clinical isolates that have not acquired FOM-modifying genes or mutations in murA. However, there are a few strains whose mechanisms of reduced susceptibility to FOM are still unclear.

  11. Characterization of Escherichia coli isolated from calf diarrhea in and around Kombolcha, South Wollo, Amhara Region, Ethiopia.

    PubMed

    Gebregiorgis, Ashenafi; Tessema, Tesfaye Sisay

    2016-02-01

    This study was carried out from October 2012 to end of February 2013 in and around Kombolcha, Amhara regional state, Ethiopia, using a total of 201 neonatal calves aged 1 day to 4 months and suffering from diarrhea. The objectives of the study were to isolate Escherichia coli from diarrheic calves, and to determine E. coli biotypes and risk factors associated with its isolation. The fecal samples were collected, transported, and processed following standard microbiological procedures. Seventy-four isolates of E. coli were identified. Yellowish diarrhea, younger age, and low-colostrum feeding were significantly associated with rate of E. coli isolation (P < 0.05). Then the 74 isolates of E. coli were biotyped using fermentation of 9 sugars and grouped into 12 biotypes; the most dominant was biotype III (36.8 %). Finally, by comparing with studies elsewhere, from the 12 isolated biotypes, 3 of them were suggested to be enteropathogenic E. coli (EPEC), entherotoxigenic E. coli (ETEC), and adhesion and effacing E. coli (AEEC) pathogenic strains. The present study showed that E. coli accounted for 37 % of calf diarrhea, with very diverse biotypes.

  12. Whole-Genome Sequences of the Archetypal K1 Escherichia coli Neonatal Isolate RS218 and Contemporary Neonatal Bacteremia Clinical Isolates SCB11, SCB12, and SCB15.

    PubMed

    Day, Michael W; Jackson, Lydgia A; Akins, Darrin R; Dyer, David W; Chavez-Bueno, Susana

    2015-02-26

    Neonatal bacteremia Escherichia coli strains commonly belong to the K1 capsular type. Their ability to cause invasive neonatal disease appears to be determined by other virulence factors that have yet to be identified. We report here the genome sequences of four E. coli neonatal bacteremia isolates, including that of the archetypal strain RS218.

  13. Detection and source tracking of Escherichia coli, harboring intimin and Shiga toxin genes, isolated from the Little Bighorn River, Montana.

    PubMed

    Hamner, Steve; Broadaway, Susan C; Berg, Ethan; Stettner, Sean; Pyle, Barry H; Big Man, Nita; Old Elk, Joseph; Eggers, Margaret J; Doyle, John; Kindness, Larry; Good Luck, Brandon; Ford, Timothy E; Camper, Anne C

    2014-08-01

    The Little Bighorn River flows through the Crow Indian Reservation in Montana. In 2008, Escherichia coli concentrations as high as 7179 MPN/100 ml were detected in the river at the Crow Agency Water Treatment Plant intake site. During 2008, 2009, and 2012, 10 different serotypes of E. coli, including O157:H7, harboring both intimin and Shiga toxin genes were isolated from a popular swim site of the Little Bighorn River in Crow Agency. As part of a microbial source tracking study, E. coli strains were isolated from river samples as well as from manure collected from a large cattle feeding operation in the upper Little Bighorn River watershed; 23% of 167 isolates of E. coli obtained from the manure tested positive for the intimin gene. Among these manure isolates, 19 were identified as O156:H8, matching the serotype of an isolate collected from a river sampling site close to the cattle feeding area.

  14. Antimicrobial resistance trends among canine Escherichia coli isolates obtained from clinical samples in the northeastern USA, 2004-2011.

    PubMed

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

    2015-04-01

    Our objectives were to describe the antimicrobial susceptibility of Escherichia coli isolates from dogs in the northeastern USA and to identify temporal trends in resistance to selected antimicrobial agents. Data were collected retrospectively for all canine E. coli isolates from clinical samples submitted to Cornell University's Animal Health Diagnostic Center between January 1, 2004 and December 31, 2011. Antimicrobial susceptibility testing was performed on 3519 canine E. coli isolates; frequency of resistance to each agent ranged from 0.4% (amikacin) to 34.3% (ampicillin). No trends were evident among urinary isolates, but cephalosporin resistance remained consistently high. Among non-urinary isolates, there was evidence of a significantly increasing trend in prevalence of resistance to several agents, including cephalosporins, enrofloxacin, and tetracycline. These data suggest that some of the most commonly used antimicrobial agents in companion animal practice are becoming less effective against canine E. coli infections outside the urinary tract.

  15. Distribution of Strain Type and Antimicrobial Susceptibility of Escherichia coli Isolates Causing Meningitis in a Large Urban Setting in Brazil

    PubMed Central

    Berman, Hillary; Barberino, Maria Goreth; Moreira, Edson Duarte; Riley, Lee

    2014-01-01

    The clinical management of meningitis caused by Escherichia coli is greatly complicated when the organism becomes resistant to broad-spectrum antibiotics. We sought to characterize the antimicrobial susceptibilities, sequence types (ST), and presence of known drug resistance genes of E. coli isolates that caused meningitis between 1996 and 2011 in Salvador, Brazil. We then compared these findings to those for E. coli isolates from community-acquired urinary tract infections (UTI) that occurred during the same time period and in the same city. We found that 19% of E. coli isolates from cases of meningitis and less than 1% of isolates from UTI were resistant to third-generation cephalosporins. The sequence types of E. coli isolates from cases of meningitis included ST131, ST69, ST405, and ST62, which were also found among isolates from UTI. Additionally, among the E. coli isolates that were resistant to third-generation cephalosporins, we found genes that encode the extended-spectrum beta-lactamases CTX-M-2, CTX-M-14, and CTX-M-15. These observations demonstrate that compared to E. coli strains isolated from cases of community-acquired UTI, those isolated from cases of meningitis are more resistant to third-generation cephalosporins, even though the same sequence types are shared between the two forms of extraintestinal infections. PMID:24523478

  16. Distribution of strain type and antimicrobial susceptibility of Escherichia coli isolates causing meningitis in a large urban setting in Brazil.

    PubMed

    Berman, Hillary; Barberino, Maria Goreth; Moreira, Edson Duarte; Riley, Lee; Reis, Joice N

    2014-05-01

    The clinical management of meningitis caused by Escherichia coli is greatly complicated when the organism becomes resistant to broad-spectrum antibiotics. We sought to characterize the antimicrobial susceptibilities, sequence types (ST), and presence of known drug resistance genes of E. coli isolates that caused meningitis between 1996 and 2011 in Salvador, Brazil. We then compared these findings to those for E. coli isolates from community-acquired urinary tract infections (UTI) that occurred during the same time period and in the same city. We found that 19% of E. coli isolates from cases of meningitis and less than 1% of isolates from UTI were resistant to third-generation cephalosporins. The sequence types of E. coli isolates from cases of meningitis included ST131, ST69, ST405, and ST62, which were also found among isolates from UTI. Additionally, among the E. coli isolates that were resistant to third-generation cephalosporins, we found genes that encode the extended-spectrum beta-lactamases CTX-M-2, CTX-M-14, and CTX-M-15. These observations demonstrate that compared to E. coli strains isolated from cases of community-acquired UTI, those isolated from cases of meningitis are more resistant to third-generation cephalosporins, even though the same sequence types are shared between the two forms of extraintestinal infections.

  17. Emergence and Dissemination of ST131 Escherichia coli Isolates Among Patients with Hospital-Acquired Pneumonia in Asian Countries.

    PubMed

    Cha, Min Kyeong; Kang, Cheol-In; Kim, So Hyun; Thamlikitkul, Visanu; So, Thomas Man-Kit; Ha, Young Eun; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon

    2017-01-01

    We investigated the molecular epidemiology and microbiological characteristics of 51 Escherichia coli isolates causing hospital-acquired pneumonia (HAP) in eight Asian areas. Sequence type 131 (ST131) was the most prevalent among E. coli isolates causing HAP, especially in South Korea, Thailand, and the Philippines. The current study showed that CTX-M-15-producing E. coli ST131 has emerged in and disseminated among patients with HAP in Asia. Our data suggest that this pandemic clone poses an important public health threat even in nosocomial infections.

  18. Characterization and survival of environmental Escherichia coli O26 isolates in ground beef and environmental samples.

    PubMed

    Palmer, Christine E; Bratcher, Christy L; Singh, Manpreet; Wang, Luxin

    2015-04-01

    In addition to Escherichia coli O157:H7, shiga toxin-producing E. coli (STEC) O26 was added to the zero-tolerance adulterant list together with other 5 non-O157 STEC serogroups in 2012. Four farm O26 isolates were used in this study; they were obtained from a on-farm survey study conducted in Alabama. The presence of 3 major pathogenic genes (stx1, stx2, and eaeA) was determined through multiplex polymerase chain reaction (PCR). Two major pathogenic gene profiles were observed: 3 of the farm isolates contain only the eaeA gene whereas 1 farm isolate has both the eaeA and the stx1 genes. No significant difference was seen among the 4 farm isolates in the antibiotic resistance tests. To test their survival in ground beef and environmental samples, 2 inoculums were prepared and inoculated at various concentrations into samples of ground beef, bovine feces, bedding materials, and trough water. One inoculum was made of 3 farm isolates containing only the eaeA gene and another inoculum contained the isolate with both the eaeA and stx1 genes. Inoculated beef samples were stored at 4 °C for 10 d and the inoculated environmental samples were stored at ambient temperature for 30 d. Results showed that virulence gene profiles do not have an impact on O26's ability to survive in ground beef and in environment (P > 0.05). The inoculation levels, sample types as well as the storage times are the major factors that impact O26 survival (P < 0.05).

  19. Molecular Characterization of Multidrug-Resistant Escherichia coli Isolates from Irish Cattle Farms▿†

    PubMed Central

    Karczmarczyk, Maria; Walsh, Ciara; Slowey, Rosemarie; Leonard, Nola; Fanning, Séamus

    2011-01-01

    This study describes the genotypic characteristics of a collection of 100 multidrug-resistant (MDR) Escherichia coli strains recovered from cattle and the farm environment in Ireland in 2007. The most prevalent antimicrobial resistance identified was to streptomycin (100%), followed by tetracycline (99%), sulfonamides (98%), ampicillin (82%), and neomycin (62%). Resistance was mediated predominantly by strA-strB (92%), tetA (67%), sul2 (90%), blaTEM (79%), and aphA1 (63%) gene markers, respectively. Twenty-seven isolates harbored a class 1 integrase (intI1), while qacEΔ1 and sul1 markers were identified in 25 and 26 isolates, respectively. The variable regions of these integrons contained aminoglycoside, trimethoprim, and β-lactam resistance determinants (aadA12, aadB-aadA1, blaOXA-30-aadA1, dfrA1-aadA1, dfrA7). Class 2 integrons were identified less frequently (4%) and contained the gene cassette array dfrA1-sat1-aadA1. Resistance to ampicillin, neomycin, streptomycin, sulfonamide, and tetracycline was associated with transferable high-molecular-weight plasmids, as demonstrated by conjugation assays. A panel of virulence markers was screened for by PCR, and genes identified included vt1, K5 in 2 isolates, papC in 10 isolates, and PAI IV536 in 37 isolates. MDR commensal E. coli isolates from Irish cattle displayed considerable diversity with respect to the genes identified. Our findings highlight the importance of the commensal microflora of food-producing animals as a reservoir of transferable MDR. PMID:21856840

  20. 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.

  1. 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

  2. Pulsed-field gel electrophoresis patterns of Escherichia coli O157 isolates from Kansas feedlots.

    PubMed

    Sargeant, J M; Shi, X; Sanderson, M W; Renter, D G; Nagaraja, T G

    2006-01-01

    This study investigated the prevalence and distribution of Escherichia coli O157 genetic types within and among feedlots using pulsed-field gel electrophoresis to separate XbaI-digested DNA. The study population consisted of 300 pens of cattle in 30 feedlots in Kansas that were sampled (feces, water, and water sediment) within a month of being shipped for slaughter. The prevalence of E. coli O157 was 8.5% in feces, 3.1% in water, and 4.5% in water sediment samples. A total of 424 E. coli O157 isolates were characterized by pulsed-field gel electrophoresis, and 139 subtypes (100% Dice similarity with no band differences) were identified. The majority of subtypes (70/139) was identified only once, but nine were identified 10 or more times. Identical subtypes were recovered from both feces and water tanks in 10 feedlots. The majority of subtypes were identified in only one feedlot, and the number of subtypes ranged from one to 23 within a feedlot and from one to seven within a pen. There were 10 feedlots with at least 15 positive samples. In these 10 feedlots, the most common subtype accounted for 16.9-78.6% of the isolates. Common subtypes differed among feedlots. In eight of the 10 feedlots, the most common subtype was identified in multiple pens. The results support a complex ecology for E. coli O157 in feedlot operations, with factors associated with exposure and transmission likely acting at a common level for multiple feedlots, within feedlots, and within pens of cattle.

  3. Densities and antimicrobial resistance of Escherichia coli isolated from marine waters and beach sands.

    PubMed

    Andrade, Vanessa da Costa; Zampieri, Bruna Del Busso; Ballesteros, Eliete Rodrigues; Pinto, Aline Bartelochi; de Oliveira, Ana Julia Fernandes Cardoso

    2015-06-01

    Bacterial resistance is a rising problem all over the world. Many studies have showed that beach sands can contain higher concentration of microorganisms and represent a risk to public health. This paper aims to evaluate the densities and resistance to antimicrobials of Escherichia coli strains, isolated from seawater and samples. The hypothesis is that microorganisms show higher densities in contaminated beach sands and more antimicrobial resistance than the water column. Density, distribution, and antimicrobial resistance of bacteria E. coli were evaluate in seawater and sands from two recreational beaches with different levels of pollution. At the beach with higher degree of pollution (Gonzaguinha), water samples presented the highest densities of E. coli; however, higher frequency of resistant strains was observe in wet sand (71.9 %). Resistance to a larger number of antimicrobial groups was observe in water (betalactamics, aminoglycosides, macrolides, rifampicins, and tetracyclines) and sand (betagalactamics and aminoglycosids). In water samples, highest frequencies of resistance were obtain against ampicilin (22.5 %), streptomycin (15.0 %), and rifampicin (15.0 %), while in sand, the highest frequencies were observe in relation to ampicilin (36.25 %) and streptomycin (23.52 %). At the less polluted beach, Ilha Porchat, highest densities of E. coli and higher frequency of resistance were obtain in wet and dry sand (53.7 and 53.8 %, respectively) compared to water (50 %). Antimicrobial resistance in strains isolated from water and sand only occurred against betalactamics (ampicilin and amoxicilin plus clavulanic acid). The frequency and variability of bacterial resistance to antimicrobials in marine recreational waters and sands were related to the degree of fecal contamination in this environment. These results show that water and sands from beaches with a high index of fecal contamination of human origin may be potential sources of contamination by pathogens

  4. Virulence factors of lactose-negative Escherichia coli strains isolated from children with diarrhea in Somalia.

    PubMed Central

    Nicoletti, M; Superti, F; Conti, C; Calconi, A; Zagaglia, C

    1988-01-01

    Lactose-negative Escherichia coli strains were isolated at high frequency from children with diarrhea in Somalia during a 2-year study on diarrheal diseases. Sixty-four of these strains, considered to be a representative sample, were characterized for virulence factors, plasmid profiles, and antibiotic resistance. Of these strains, 5 were recognized as enteroinvasive E. coli (they were serotyped as O135:K-:H-), 6 belonged to classical enteropathogenic E. coli serotypes, 9 were able to adhere to tissue culture cells (of these, 4 showed a pattern of localized adherence and 1 was an enteropathogenic strain), 18 were both adherent and hemolytic, and 8 were simply hemolytic. None hybridized with 32P-labeled heat-labile or heat-stable (a and b) enterotoxin gene probes or produced moderate or high-level cytotoxic effects on HeLa cells. Of the 64 strains examined, 24 produced mannose-resistant hemagglutination with human, chicken, and monkey erythrocytes. One of these was serotyped as O4:K-:H8, and a rabbit O antiserum raised against this strain allowed us to establish that 23 strains had the same O antigen. The 23 O4 strains were hemolytic and were not enterotoxic for rabbit ileal loops, and intact bacteria were able to destroy tissue culture cell monolayers very rapidly. The uniformity of the antibiotic resistance pattern and of the plasmid DNA content, together with the fact that they were isolated in different years and in different children, suggests that the O4 strains must be epidemiologically relevant in Somalia. A possible diarrheagenic role for the adherent-hemolytic E. coli strains is also discussed. Images PMID:3281977

  5. Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates.

    PubMed

    Paixão, A C; Ferreira, A C; Fontes, M; Themudo, P; Albuquerque, T; Soares, M C; Fevereiro, M; Martins, L; Corrêa de Sá, M I

    2016-07-01

    Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E.coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E.coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.

  6. 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

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

    PubMed Central

    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

  8. Antibiotic resistance plasmids spread among natural isolates of Escherichia coli in spite of CRISPR elements.

    PubMed

    Touchon, Marie; Charpentier, Sophie; Pognard, Dominique; Picard, Bertrand; Arlet, Guillaume; Rocha, Eduardo P C; Denamur, Erick; Branger, Catherine

    2012-12-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPRs) are implicated in defence against foreign DNA in various archaeal and bacterial species. They have also been associated with a slower spread of antibiotic resistance. However, experimental and evolutionary studies raise doubts about the role of CRISPRs as a sort of immune system in Escherichia coli. We studied a collection of 263 natural E. coli isolates from human and animal hosts, representative of the phylogenetic and lifestyle diversity of the species and exhibiting various levels of plasmid-encoded antibiotic resistance. We characterized the strains in terms of CRISPRs, performed replicon typing of the plasmids and tested for class 1 integrons to explore the possible association between CRISPRs and the absence of plasmids and mobile antibiotic resistance determinants. We found no meaningful association between the presence/absence of the cas genes, reflecting the activity of the CRISPRs, and the presence of plasmids, integrons or antibiotic resistance. No CRISPR in the collection contained a spacer that matched an antibiotic resistance gene or element involved in antibiotic resistance gene mobilization, and 79.8 % (210/263) of the strains lacked spacers matching sequences in the 2282 plasmid genomes available. Hence, E. coli CRISPRs do not seem to be efficient barriers to the spread of plasmids and antibiotic resistance, consistent with what has been reported for phages, and contrary to reports concerning other species.

  9. Antibiotic resistance plasmids spread among natural isolates of Escherichia coli in spite of CRISPR elements.

    PubMed

    Touchon, Marie; Charpentier, Sophie; Pognard, Dominique; Picard, Bertrand; Arlet, Guillaume; Rocha, Eduardo P C; Denamur, Erick; Branger, Catherine

    2012-12-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPRs) are implicated in defence against foreign DNA in various archaeal and bacterial species. They have also been associated with a slower spread of antibiotic resistance. However, experimental and evolutionary studies raise doubts about the role of CRISPRs as a sort of immune system in Escherichia coli. We studied a collection of 263 natural E. coli isolates from human and animal hosts, representative of the phylogenetic and lifestyle diversity of the species and exhibiting various levels of plasmid-encoded antibiotic resistance. We characterized the strains in terms of CRISPRs, performed replicon typing of the plasmids and tested for class 1 integrons to explore the possible association between CRISPRs and the absence of plasmids and mobile antibiotic resistance determinants. We found no meaningful association between the presence/absence of the cas genes, reflecting the activity of the CRISPRs, and the presence of plasmids, integrons or antibiotic resistance. No CRISPR in the collection contained a spacer that matched an antibiotic resistance gene or element involved in antibiotic resistance gene mobilization, and 79.8% (210/263) of the strains lacked spacers matching sequences in the 2282 plasmid genomes available. Hence, E. coli CRISPRs do not seem to be efficient barriers to the spread of plasmids and antibiotic resistance, consistent with what has been reported for phages, and contrary to reports concerning other species.

  10. Effect of antimicrobial dosage regimen on Salmonella and Escherichia coli isolates from feeder swine.

    PubMed

    Wagner, Bruce A; Straw, Barbara E; Fedorka-Cray, Paula J; Dargatz, David A

    2008-03-01

    A body of evidence exists that suggests that antimicrobial use in food animals leads to resistance in both pathogenic and commensal bacteria. This study focused on the impact of three different antimicrobial regimes (low-level continuous, pulse, and no antimicrobial) for two antimicrobials (chlortetracycline and tylosin) on the presence of Salmonella spp. and on the prevalence of antimicrobial resistance of both Salmonella spp. and nonspecific Escherichia coli in fecal samples from feeder swine. The prevalence of fecal samples positive for Salmonella spp. significantly decreased between the samples taken at feeder placement compared to samples taken when the animals were close to market weight. Differences in resistance of Salmonella spp. did not appear to be influenced by dosing treatment including the control. Analysis of antimicrobial resistance examining both susceptibility and resistance, as well as MIC outcomes, demonstrated that only resistance to cephalothin increased in E. coli under the pulse chlortetracycline treatment. These results suggest that the dosing regimes examined in this study did not lead to an increase in either the prevalence of Salmonella spp. or the prevalence of antimicrobial resistance in isolates of Salmonella spp. or E. coli.

  11. First isolation of enteroaggregative Escherichia coli O104:H4 from a diarrhea case in Argentina.

    PubMed

    Carbonari, Claudia C; Deza, Natalia; Flores, Mario; Gasparini, Alejandra; Manfredi, Eduardo; Rivas, Marta

    2014-01-01

    We describe the first isolation of an enteroaggregative Escherichia coli (EAEC) O104:H4 strain associated with an acute diarrhea case in Argentina. Two multiplex PCRs (mPCR) were performed as screening of genes mPCR1 (eae, lt, and st) and mPCR2 (IpaH, aggR, stx1 and stx2). A mPCR to detect the rfbO104, fliCH4 and terD genes, and PCR assays for the detection of pCVD432 plasmid, aaiC and lpfO113 genes were included. Biochemical and antimicrobial susceptibility assays as well as serotyping were performed. The identified E. coli strain was susceptible to all antimicrobials tested and harbored the aggR, aaiC, pCVD432 plasmid, lpfO113, rfbO104, fliCH4 and terD genes. Although serotype EAEC O104:H4 rarely spreads and sporadic cases have been reported, global concern increased after the large-scale outbreak in Europe in 2011. The finding of EAEC O104:H4 reinforces the need for improved methodologies for the detection of all E. coli pathotypes. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  12. Evaluating a murine model of endometritis using uterine isolates of Escherichia coli from postpartum buffalo

    PubMed Central

    Dar, S. H.; Qureshi, S.; Palanivelu, M.; Muthu, S.; Mehrotra, S.; Jan, M. H.; Chaudhary, G. R.; Kumar, H.; Saravanan, R.; Narayanan, K.

    2016-01-01

    Ascending infection of the uterus with Gram-negative bacteria is responsible for postpartum endometritis in cattle and buffalo and can adversely affect fertility. Development of a laboratory animal model for bovine endometritis would facilitate the understanding of the pathogenesis as it is difficult to conduct controlled experimentation in the native host. In the present study, 30 virgin Swiss Albino mice (5-8 weeks old) were used to evaluate the pathogenic potential of Escherichia coli, isolated from the normally calved postpartum buffalo to induce endometritis. Mice in the diestrus phase of the estrous cycle were randomly allotted to one of the following four intravaginal inoculation (100 μL) treatments: EG (experimental group)-1: sterile normal saline; EG-2, -3 and -4: E. coli@ 1.5 × 104, 105 and 106 CFU/ml, respectively. The animals were then scarified 36 h post-inoculation to study gross and microscopical lesions. Gross changes were confined to EG-4. Acute endometritis was recorded in 50% of the EG-3 and 66.7% of the EG-4. The rate of acute endometritis development was significantly higher in EG-4 (P<0.05) as compared to the other groups. The present study demonstrated that the animal model for bubaline endometritis can be developed in mice by intravaginal inoculation of E. coli@ 1.5 × 106 CFU/ml at diestrus. Ease of intravaginal inoculation, apparent absence of systemic involvement and high infective rate are the advantages of the model over other studies. PMID:27822246

  13. A new affinity approach to isolate Escherichia coli 6S RNA with histidine-chromatography.

    PubMed

    Martins, R; Queiroz, J A; Sousa, F

    2010-01-01

    6S RNA is an abundant non-coding RNA in Escherichia coli (E. coli), but its function has not been discovered until recently. The first advance on 6S RNA function was the demonstration of its ability to bind the σ(70)-holoenzyme form of RNA polymerase, inhibiting its activity and consequently the transcription process. The growing interest in the investigation of non-coding small RNAs (sRNA) calls for the development of new methods for isolation and purification of RNA. This work presents an optimized RNA extraction procedure and describes a new affinity chromatography method using a histidine support to specifically purify 6S RNA from other E. coli sRNA species. The RNA extraction procedure was optimized, and a high yield was obtained in the separation of sRNA and ribosomal RNA (rRNA) from total RNA (RNAt). This improved method takes advantage of its simplicity and significant cost reduction, since some complex operations have been eliminated. A purification strategy was also developed to separate 6S RNA from an sRNA mixture. Pure RNA can be advantageously obtained using the histidine-affinity chromatography method, aiming at its application to structural or functional studies. Copyright © 2010 John Wiley & Sons, Ltd.

  14. Isolation and characterization of norfloxacin-resistant mutants of Escherichia coli K-12.

    PubMed Central

    Hirai, K; Aoyama, H; Suzue, S; Irikura, T; Iyobe, S; Mitsuhashi, S

    1986-01-01

    We isolated spontaneous mutants from Escherichia coli K-12 with low-level resistance to norfloxacin. These mutants were classified into the following three types on the basis of their properties: (i) NorA appeared to result for mutation in the gyrA locus for the A subunit of DNA gyrase; (ii) NorB showed low-level resistance to quinolones and other antimicrobial agents (e.g., cefoxitin, chloramphenicol, and tetracycline), and the norB gene was considered to map at about 34 min on the E. coli K-12 chromosome; (iii) NorC was less susceptible to norfloxacin and ciprofloxacin but was hypersusceptible to hydrophobic quinolones such as nalidixic acid and rosoxacin, hydrophobic antibiotics, dyes, and detergents. Susceptibility to bacteriophages and the hydrophobicity of the NorC cell surface also differed from that of the parent strain. The norC gene was located near the lac locus at 8 min on the E. coli K-12 chromosome. Both NorB and NorC mutants had a lower rate of norfloxacin uptake, and it was found that the NorB mutant was altered in OmpF porin and that the NorC mutant was altered in both OmpF porin and apparently in the lipopolysaccharide structure of the outer membrane. PMID:3532944

  15. Detection of mcr-1 colistin resistance gene in polyclonal Escherichia coli isolates in Barcelona, Spain, 2012 to 2015.

    PubMed

    Prim, Núria; Rivera, Alba; Rodríguez-Navarro, Judith; Español, Montserrat; Turbau, Miquel; Coll, Pere; Mirelis, Beatriz

    2016-01-01

    Colistin resistance was detected in 53 of 10,011 Escherichia coli (0.5%) by prospective phenotypic testing of consecutive clinical isolates in a single hospital in Barcelona, Spain (2012-15). The mcr-1 gene was retrospectively identified by PCR and sequencing in 15 of 50 available isolates. Each isolate had a unique PFGE pattern except for two. This clonal diversity supports the hypothesis of horizontal dissemination of the mcr-1 gene in the local study population.

  16. Phylogenetic grouping, epidemiological typing, analysis of virulence genes, and antimicrobial susceptibility of Escherichia coli isolated from healthy broilers in Japan

    PubMed Central

    2014-01-01

    Background The aim of our study was to investigate the possible etiology of avian colibacillosis by examining Escherichia coli isolates from fecal samples of healthy broilers. Findings Seventy-eight E. coli isolates from fecal samples of healthy broilers in Japan were subjected to analysis of phylogenetic background, virulence-associated gene profiling, multi-locus sequence typing (MLST), and antimicrobial resistance profiling. Phylogenetic analysis demonstrated that 35 of the 78 isolates belonged to group A, 28 to group B1, one to group B2, and 14 to group D. Virulence-associated genes iutA, iss, cvaC, tsh, iroN, ompT, and hlyF were found in 23 isolates (29.5%), 16 isolates (20.5%), nine isolates (11.5%), five isolates (6.4%), 19 isolates (24.4%), 23 isolates (29.5%), and 22 isolates (28.2%) respectively. Although the genetic diversity of group D isolates was revealed by MLST, the group D isolates harbored iutA (10 isolates, 71.4%), iss (6 isolates, 42.9%), cvaC (5 isolates, 35.7%), tsh (3 isolates, 21.4%), hlyF (9 isolates, 64.3%), iroN (7 isolates, 50.0%), and ompT (9 isolates, 64.3%). Conclusions Our results indicated that E. coli isolates inhabiting the intestines of healthy broilers pose a potential risk of causing avian colibacillosis. PMID:25061511

  17. Complete Genome Sequence of a Colistin Resistance Gene (mcr-1)-Bearing Isolate of Escherichia coli from the United States

    PubMed Central

    Ladely, Scott R.; Bono, James L.; Plumblee, Jodie R.; Hall, M. Carolina; Genzlinger, Linda L.; Cook, Kimberly L.

    2016-01-01

    Transmissible colistin resistance conferred by the mcr-1 gene-bearing IncI2 plasmid has been recently reported in Escherichia coli in the United States. We report here the completed genome sequence of a second E. coli strain isolated from swine in the United States that carried the mcr-1 gene on an IncI2-type plasmid. PMID:27834721

  18. Antimicrobial Activity of Lactobacillus spp. Isolated From Fecal Flora of Healthy Breast-Fed Infants Against Diarrheagenic Escherichia coli

    PubMed Central

    Davoodabadi, Abolfazl; Soltan Dallal, Mohammad Mehdi; Lashani, Elahe; Tajabadi Ebrahimi, Maryam

    2015-01-01

    Background: Among the enteric pathogens, diarrheagenic Escherichia coli are important causes of diarrhea in children in both developing and industrialized countries. Some Lactobacillus species are commonly used as probiotics, with effects especially against acute diarrhea in childhood. Objectives: The aim of this study was to explore antimicrobial activity of Lactobacillus strains isolated from fecal flora of healthy breast-fed infants against five diarrheagenic E. coli pathotypes such as enteroaggregative E. coli (EAEC), enterohaemorrhagic E. coli (EHEC) enteroinvasive E. coli (EIEC), enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). Materials and Methods: Fecal samples were collected from seven healthy breast-fed infants between 1 to 18 months of age in Tehran city, Iran. Identification of Lactobacillus isolates was performed by biochemical and 16S rRNA gene sequencing methods. An agar well diffusion assay was used for detection of antimicrobial activity of Lactobacillus isolates against five diarrheagenic E. coli pathotypes. Results: A total of 20 Lactobacillus isolates were identified from stool samples. Lactobacillus fermentum was the most frequently isolated strain, followed by L. plantarum and L. rhamnosus. Seven Lactobacillus strains including L. fermentum (four isolates), L. paracasei (one isolate), L. plantarum (one isolate) and L. rhamnosus (one isolate) had a mild inhibitory activity against diarrheagenic E. coli. The mechanism of inhibitory activity of Lactobacillus strains appeared to be due to the production of organic acids or hydrogen peroxide. Conclusions: Our findings show that Lactobacillus strains with human origin had a mild inhibitory activity against the diarrheagenic E. coli, and these strains may be useful as probiotic candidates in prevention of intestinal infections caused by diarrheagenic E. coli. PMID:26865944

  19. Detection and isolation of Shiga toxin-producing Escherichia coli (STEC) O104 from sprouts.

    PubMed

    Baranzoni, Gian Marco; Fratamico, Pina M; Rubio, Fernando; Glaze, Thomas; Bagi, Lori K; Albonetti, Sabrina

    2014-03-03

    Shiga toxin-producing Escherichia coli (STEC) strains belonging to serogroup O104 have been associated with sporadic cases of illness and have caused outbreaks associated with milk and sprouts. An outbreak that occurred in Europe in 2011 linked to fenugreek sprouts was caused by E. coli O104:H4 that had characteristics of an enteroaggregative E. coli (EAEC) but carried the gene that encoded for Shiga toxin 2. In this study, methods were developed for detection of this enteroaggregative STEC O104, as well as STEC O104 in sprouts. Multiplex PCR assays for enteroaggregative STEC O104:H4 targeted the stx2, aggR, and wzx104 genes, and for STEC O104 targeted the stx1-2, ehxA, and wzx104 genes. After incubating artificially contaminated sprouts at 4 °C for 48 h and overnight enrichment in modified buffered peptone water with pyruvate supplemented with three antibiotics (mBPWp), the pathogens were detected in all samples inoculated at a level of ca. 100CFU/25 g. Several samples inoculated at lower concentrations of ca. 10CFU/25 g were negative by the PCR assays, and this could have been due to cells not surviving or not being able to recover after the stress treatment at 4 °C for 48 h. For isolation of the pathogens, immunomagnetic separation (IMS) using magnetic beads coated with antibodies against O104 were employed, and this was followed by plating the beads onto mRBA and CHROMagar STEC O104 for isolation of E. coli O104:H4 and mRBA and CHROMagar STEC for isolation of E. coli O104:H7. Presumptive colonies were confirmed by agglutination using latex particles attached to antibodies against serogroup O104 and by the multiplex PCR assays. The methodologies described in this study for detection of enteroaggregative STEC O104:H4 and STEC O104 include the use of IMS and latex reagents for serogroup O104, and they enhance the ability to detect and isolate these pathogens from sprouts and potentially other foods, as well. Published by Elsevier B.V.

  20. Diversity of Cell Properties and Transport Behavior Among 12 Enviromental Escherichia Coli Isolates

    USDA-ARS?s Scientific Manuscript database

    Escherichia coli is a commonly used indicator organism for detecting the presence of fecal-borne pathogenic microorganisms in water supplies. The importance of E. coli as an indicator organism has led to numerous studies looking at surface characteristics and transport behavior of this important mi...

  1. Characterization of Escherichia coli 0157:H7 strains isolated from supershedding cattle

    USDA-ARS?s Scientific Manuscript database

    Previous reports have indicated that a small proportion of cattle shedding high levels of Escherichia coli O157:H7 is the main source for transmission of this organism between animals. Cattle achieving a fecal shedding status of 10**4 CFU of E. coli O157: H7/gram or greater are now referred to as su...

  2. Complete genome sequence and comparison of two Shiga toxin-producing Escherichia coli O104 isolates

    USDA-ARS?s Scientific Manuscript database

    Shiga toxin-producing Escherichia coli (STEC) O104 strains have been associated with sporadic cases of illness and have caused outbreaks associated with milk and sprouts. E. coli O104:H21 caused an outbreak associated with milk in the U.S. in 1994. In this study, next generation sequencing techno...

  3. Mercury volatilization by R factor systems in Escherichia coli isolated from aquatic environments of India.

    PubMed

    Gupta, Neerja; Ali, Arif

    2004-02-01

    Ten Escherichia coli strains isolated from five different aquatic environments representing three distinct geographical regions of India showed significantly high levels of tolerance to the inorganic form of mercury, i.e., mercuric chloride (HgCl(2)). MRD14 isolated from the Dal Lake (Kashmir) could tolerate the highest concentration of HgCl(2), i.e., 55 microg/mL, and MRF1 from the flood water of the Yamuna River (Delhi) tolerated the lowest concentration, i.e., 25 microg/mL. All ten strains revealed the presence of a plasmid of approximately 24 kb, and transformation of the isolated plasmids into the mercury-sensitive competent cells of E. coli DH5alpha rendered the transformants resistant to the same concentration of mercury as the wild-type strains. Mating experiments were performed to assess the self-transmissible nature of these promiscuous plasmids. The transfer of mercury resistance from these wild-type strains to the mercury-sensitive, naladixic acid-resistant E. coli K12 (F(-) lac(+)) strain used as a recipient was observed in six of the nine strains tested. Transconjugants revealed the presence of a plasmid of approximately 24 kb. An evaluation of the mechanism of mercury resistance in the three most efficient strains (MRG12, MRD11, and MRD14) encountered in our study was determined by cold vapor atomic absorption spectroscopy (CV-AAS), and it was noted that resistance to HgCl(2) was conferred by conversion of the toxic ionic form of mercury (Hg(++)) to the nontoxic elemental form (Hg(0)) in all three strains. MRD14 volatilized mercury most efficiently.

  4. A novel multidrug resistance plasmid isolated from an Escherichia coli strain resistant to aminoglycosides.

    PubMed

    Sun, Hui; Li, Shasha; Xie, Zhijing; Yang, Fangfang; Sun, Yani; Zhu, Yanli; Zhao, Xiaomin; Jiang, Shijin

    2012-07-01

    Previous studies have reported several different plasmids that confer multidrug resistance (MDR) including resistance to aminoglycosides. In this study, we investigated the aminoglycoside resistance patterns for 224 Escherichia coli isolates from diseased chickens and ducks in China, characterized a novel MDR plasmid, and collected prevalence data on similar resistance plasmids. Antibiotic susceptibilities were determined using disc diffusion and the microdilution method. The plasmid pXZ was analysed by restriction fragment length polymorphism (RFLP) with EcoRI and SalI, and sequenced. The prevalence of similar resistance plasmids was assessed by multiplex PCR and by RFLP analysis. Among the 224 E. coli isolates, 189 (84.4%) were resistant to streptomycin, 125 (55.8%) were resistant to kanamycin, 116 (51.8%) were resistant to gentamicin, 106 (47.3%) were resistant to neomycin and 98 (43.8%) were resistant to amikacin. Among the 224 E. coli isolates, 17 contained a plasmid with the MDR-encoding region of pXZ, which showed high-level resistance to aminoglycosides (MICs of gentamicin and amikacin ≥ 512 mg/L). The plasmid pXZ was digested into five fragments by EcoRI and six fragments by SalI. The plasmid pXZ was a circular DNA molecule of 76635 bp with a 51.65% guanine + cytosine content and included four resistance genes (rmtB, fosA3, bla(TEM-1) and bla(CTX-M-24)). A novel MDR plasmid, pXZ, harbouring four resistance genes (rmtB, fosA3, bla(TEM-1) and bla(CTX-M)) was identified. To our knowledge, this is the first report of an aminoglycoside resistance plasmid harbouring the fosA3 gene.

  5. Characterization of Extraintestinal Pathogenic Escherichia coli isolated from retail poultry meats from Alberta, Canada.

    PubMed

    Aslam, Mueen; Toufeer, Mehdi; Narvaez Bravo, Claudia; Lai, Vita; Rempel, Heidi; Manges, Amee; Diarra, Moussa Sory

    2014-05-02

    Extraintestinal Pathogenic Escherichia coli (ExPEC) have the potential to spread through fecal waste resulting in the contamination of both farm workers and retail poultry meat in the processing plants or environment. The objective of this study was to characterize ExPEC from retail poultry meats purchased from Alberta, Canada and to compare them with 12 human ExPEC representatives from major ExPEC lineages. Fifty-four virulence genes were screened by a set of multiplex PCRs in 700 E. coli from retail poultry meat samples. ExPEC was defined as the detection of at least two of the following virulence genes: papA/papC, sfa, kpsMT II and iutA. Genetic relationships between isolates were determined using pulsed field gel electrophoresis (PFGE). Fifty-nine (8.4%) of the 700 poultry meat isolates were identified as ExPEC and were equally distributed among the phylogenetic groups A, B1, B2 and D. Isolates of phylogenetic group A possessed up to 12 virulence genes compared to 24 and 18 genes in phylogenetic groups B2 and D, respectively. E. coli identified as ExPEC and recovered from poultry harbored as many virulence genes as those of human isolates. In addition to the iutA gene, siderophore-related iroN and fyuA were detected in combination with other virulence genes including those genes encoding for adhesion, protectin and toxin while the fimH, ompT, traT, uidA and vat were commonly detected in poultry ExPEC. The hemF, iss and cvaC genes were found in 40% of poultry ExPEC. All human ExPEC isolates harbored concnf (cytotoxic necrotizing factor 1 altering cytoskeleton and causing necrosis) and hlyD (hemolysin transport) genes which were not found in poultry ExPEC. PFGE analysis showed that a few poultry ExPEC isolates clustered with human ExPEC isolates at 55-70% similarity level. Comparing ExPEC isolated from retail poultry meats provides insight into their virulence potential and suggests that poultry associated ExPEC may be important for retail meat safety

  6. Isolation of gene fusions (soi::lacZ) inducible by oxidative stress in Escherichia coli.

    PubMed Central

    Kogoma, T; Farr, S B; Joyce, K M; Natvig, D O

    1988-01-01

    Mu dX phage was used to isolate three gene fusions to the lacZ gene (soi::lacZ; soi for superoxide radical inducible) that were induced by treatment with superoxide radical anion generators such as paraquat and plumbagin. The induction of beta-galactosidase in these fusion strains with the superoxide radical generating agents required aerobic metabolism. Hyperoxygenation (i.e., bubbling of cultures with oxygen gas) also induced the fusions. On the other hand, hydrogen peroxide did not induce the fusions at concentrations that are known to invoke an adaptive response. Introduction of oxyR, htpR, or recA mutations did not affect the induction. Two of the fusion strains exhibited increased sensitivity to paraquat but not to hydrogen peroxide. The third fusion strain showed no increased sensitivity to either agent. All three fusions were located in the 45- to 61-min region of the Escherichia coli chromosome. PMID:2838846

  7. Complete Genome Sequence of Escherichia coli O157:H7 Bacteriophage phiJLA23 Isolated in Mexico

    PubMed Central

    Amarillas, Luis; Chaidez, Cristobal; Lugo, Yadira

    2013-01-01

    The bacteriophage phiJLA23 was isolated from an animal feces sample and lytic activity was demonstrated against the Escherichia coli O157:H7 strain. We report the complete nucleotide sequence of bacteriophage phiJLA23, information which may be useful for determining whether this phage is a candidate for biocontrol or another biotechnological application. PMID:23469347

  8. Draft Genome Sequence of Five Shiga Toxin-Producing Escherichia coli Strains Isolated from Wild Deer in Japan

    PubMed Central

    Ikeda, Tetsuya; Yamamoto, Shiori; Kabeya, Hidenori; Sugiyama, Hiromu; Takai, Shinji

    2017-01-01

    ABSTRACT Shiga toxin-producing Escherichia coli (STEC) is one of the major foodborne pathogens. Having observed the wide distribution of this pathogen in wild deer, we report here the draft genome sequence of five STEC strains isolated from wild deer (Cervus nippon yesoensis) in Hokkaido, Japan. PMID:28254967

  9. Escherichia coli O157:H7 bacteriophage (phi)241 isolated from an industrial cucumber fermentation at high acidity and salinity

    USDA-ARS?s Scientific Manuscript database

    A novel phage, (phi)241, specific for Escherichia coli O157:H7 was isolated from an industrial cucumber fermentation where both acidity (pH less than or equal to 3.7) and salinity (greater than or equal to 5% NaCl) were high. The phage belongs to the Myoviridae family. Its latent period was 15 min a...

  10. Complete Genome Sequence of Escherichia coli O157:H7 Bacteriophage phiJLA23 Isolated in Mexico.

    PubMed

    Amarillas, Luis; Chaidez, Cristobal; Lugo, Yadira; León-Félix, Josefina

    2013-01-01

    The bacteriophage phiJLA23 was isolated from an animal feces sample and lytic activity was demonstrated against the Escherichia coli O157:H7 strain. We report the complete nucleotide sequence of bacteriophage phiJLA23, information which may be useful for determining whether this phage is a candidate for biocontrol or another biotechnological application.

  11. Antimicrobial Resistance and Virulence Characterization among Escherichia coli Clinical Isolates Causing Severe Obstetric Infections in Pregnant Women

    PubMed Central

    Guiral, Elisabet; Sáez-López, Emma; Bosch, Jordi; Goncé, Anna; López, Marta; Sanz, Sergi; Vila, Jordi

    2015-01-01

    The virulence markers and the antimicrobial resistance profiles of 78 Escherichia coli isolates causing obstetric infections accompanied by sepsis or not were studied. Adhesion-related virulence factors were the most prevalent markers. Low rates of resistance to the antimicrobial agents used as first-line therapy suggest their correct implementation in stewardship guidelines. PMID:25740771

  12. Heterogeneity among Strains of Diffusely Adherent Escherichia coli Isolated in Brazil

    PubMed Central

    Lopes, Lucia M.; Fabbricotti, Sandra H.; Ferreira, Antonio J. P.; Kato, Maria A. M. F.; Michalski, Jane; Scaletsky, Isabel C. A.

    2005-01-01

    One hundred twelve diffusely adherent Escherichia coli strains isolated from children in a case control study were evaluated for virulence-associated characteristics, serotyping, antibiotic resistance, and plasmid profiles. Half of the strains hybridized with the probes for icuA (aerobactin) and fimH (type 1 pili); daaE (F1845 fimbriae), afa (afimbrial Dr adhesin), agg-3A (aggregative adhesion fimbria type III fimbriae), pap (P fimbriae), astA (EAST1 toxin), and shET1 (Shigella enterotoxin 1) sequences were present in <20% of the strains. The shET1 gene was noted most frequently in strains isolated from patients. A minority (7%) of the strains produced hemolysin or colicin or showed cytotoxic effects on Vero cells. Forty-five different serotypes were found. The majority (70%) of the strains presented multiple antibiotic resistance. Antibiotic resistance and diffuse adherence were located on the same conjugative plasmids. These results suggest that the transfer of these potential virulence markers could be important in the epidemiology of diffusely adherent E. coli. PMID:15815034

  13. Differential expression of two isolates of beak and feather disease virus capsid protein in Escherichia coli.

    PubMed

    Patterson, Edward I; Swarbrick, Crystall M D; Roman, Noelia; Forwood, Jade K; Raidal, Shane R

    2013-04-01

    Expression of recombinant beak and feather disease virus (BFDV) capsid-associated protein (Cap) has relied on inefficient techniques that typically produce low yields or use specialized expression systems, which greatly increase the cost and expertise required for mass production. An Escherichia coli system was used to express recombinant BFDV Cap derived from two isolates of BFDV, from a Long-billed Corella (Cacatua tenuirostris) and an Orange-bellied parrot (OBP; Neophema chrysogaster). Purification by affinity and size exclusion chromatography was optimized through an iterative process involving screening and modification of buffer constituents and pH. A buffer containing glycerol, β-mercaptoethanol, Triton X-100, and a high concentration of NaCl at pH 8 was used to increase solubility of the protein. The final concentration of the corella-isolated BFDV protein was fifteen- to twenty-fold greater than that produced in previous publications using E. coli expression systems. Immunoassays were used to confirm the specific antigenicity of recombinant Cap, verifying its validity for use in continued experimentation as a potential vaccine, a reagent in diagnostic assays, and as a concentrated sample for biological discoveries.

  14. Expanded spectrum β-lactamase producing Escherichia coli isolated from chickens with colibacillosis in Egypt.

    PubMed

    El-Shazly, D A; Nasef, S A; Mahmoud, F F; Jonas, Daniel

    2017-07-01

    Throughout the world, expanded spectrum β-lactamases (ESBL) are increasing among clinical isolates of Enterobacteriaceae, both in humans and animals. Unfortunately, there is a paucity of data on ESBL or Ampicillin class C β-lactamase (AmpC) in Egypt, although antimicrobial consumption is high in this developing country. This study aims to characterize the resistance mechanisms to expanded spectrum cephalosporins among resistant veterinary Escherichia coli isolates in Egypt. We investigated 50 clinical multi-resistant E. coli strains isolated from 20 chicken farms for production of ESBL or AmpC. Antibiotic susceptibility was tested by Clinical and Laboratory Standards Institute (CLSI) disk diffusion and ESBL confirmatory tests. PCR and sequencing were performed to screen for plasmid mediated ESBL genes and genes encoding AmpC β-lactamases. All the isolates were phylogentically classified, investigated for harboring class 1 integrons, and genotyped by amplified fragment length polymorphism (AFLP). Three strains showed ESBL and 6 strains AmpC phenotypic patterns, respectively, with confirmed ESBL genes of blaTEM-57, blaSHV-12, blaCTX-M-14, and blaCMY-2 for AmpC producing strains. All ESBL strains belonged to phylogroup D with different clones isolated from different flocks, while most of the AmpC strains belonged to phylogroup B1 (4/6) and were assigned to the same genotype distributed in 2 different farms. Class 1 integrons were disseminated in 60% of all tested strains and in 100% of ESBL and AmpC strains. These results highlight the antimicrobial resistance problem in Egypt, caused in all probability by unwise use of antimicrobials in animal husbandry. The results call for a nationwide surveillance program to monitor antimicrobial resistance. © 2017 Poultry Science Association Inc.

  15. Molecular characterization of multidrug-resistant avian pathogenic Escherichia coli isolated from septicemic broilers.

    PubMed

    Ahmed, Ashraf M; Shimamoto, Toshi; Shimamoto, Tadashi

    2013-12-01

    Avian pathogenic Escherichia coli (APEC) causes extensive mortality in poultry flocks, leading to extensive economic losses. To date, little information is available on the molecular basis of antimicrobial resistance in APEC in Africa. Therefore, the objective of this study was to characterize the virulence and antimicrobial resistance of multidrug-resistant APEC isolated from septicemic broilers in Egypt at the molecular level. Among 91 non-repetitive E. coli isolates, 73 (80.2%) carried three or more of the APEC virulence genes iroN, ompT, iss, iutA, and hlyF. All 73 APEC isolates showed multidrug resistance phenotypes, particularly against ampicillin, tetracycline, spectinomycin, streptomycin, kanamycin, and trimethoprim/sulfamethoxazole. PCR and DNA sequencing identified class 1 and class 2 integrons in 34 (46.6%) and seven (9.6%) isolates, respectively. The β-lactamase-encoding genes, bla(TEM-1), bla(TEM-104), bla(CMY-2), bla(OXA-30), bla(CTX-M-15), and bla(SHV-2); tetracycline resistance genes, tet(A), tet(B), tet(C), tet(D), and tet(E); the plasmid-mediated quinolone resistance genes, qnrA1, qnrB2, qnrS1, and aac(6')-Ib-cr, and florfenicol resistance gene, floR, were also identified in 69 (94.5%), 67 (91.8%), 47 (64.4%), and 13 (17.8%) isolates, respectively. To the best of our knowledge, this is the first report of molecular characterization of antimicrobial resistance in APEC strains from Africa.

  16. Pharmacodynamic profiling of commonly prescribed antimicrobial drugs against Escherichia coli isolates from urinary tract.

    PubMed

    Cuba, Gabriel Trova; Pignatari, Antonio Carlos Campos; Patekoski, Katya Silva; Luchesi, Lucimila Jorge; Kiffer, Carlos Roberto Veiga

    2014-01-01

    Since antimicrobial resistance among uropathogens against current first line agents has affected the management of severe urinary tract infection, we determined the likelihood that antibiotic regimens achieve bactericidal pharmacodynamic exposures using Monte Carlo simulation for five antimicrobials (ciprofloxacin, ceftriaxone, piperacillin/tazobactam, ertapenem, and meropenem) commonly prescribed as initial empirical treatment of inpatients with severe community acquired urinary tract infections. Minimum inhibitory concentration determination by Etest was performed for 205 Brazilian community urinary tract infection Escherichia coli strains from 2008 to 2012 and 74 E. coli bloodstream strains recovered from a surveillance study. Pharmacodynamic exposure was modeled via a 5000 subject Monte Carlo simulation. All isolates were susceptible to ertapenem and meropenem. Piperacillin/tazobactam, ceftriaxone and ciprofloxacin showed 100%, 97.5% and 83.3% susceptibility among outpatient isolates and 98.6%, 75.7% and 64.3% among inpatient isolates, respectively. Against outpatient isolates, all drugs except ciprofloxacin (82.7% in aggressive and 77.6% in conservative scenarios) achieved high cumulative fraction of response: carbapenems and piperacillin/tazobactam cumulative fraction of responses were close to 100%, and ceftriaxone cumulative fraction of response was 97.5%. Similar results were observed against inpatients isolates for carbapenems (100%) and piperacillin/tazobactam (98.4%), whereas ceftriaxone achieved only 76.9% bactericidal cumulative fraction of response and ciprofloxacin 61.9% (aggressive scenario) and 56.7% (conservative scenario) respectively. Based on this model, standard doses of beta-lactams were predicted to deliver sufficient pharmacodynamic exposure for outpatients. However, ceftriaxone should be avoided for inpatients and ciprofloxacin empirical prescription should be avoided in both inpatients and outpatients with complicated urinary tract

  17. Emergence of KPC-2-producing Escherichia coli isolates in an urban river in Harbin, China.

    PubMed

    Xu, Guofeng; Jiang, Yue; An, Wei; Wang, Hongdong; Zhang, Xiuying

    2015-09-01

    Three KPC-2-producing Escherichia coli (E1, E2, and E3) were recovered from water samples of an urban river in the city of Harbin, China. Antimicrobial susceptibility was determined by broth microdilution. Molecular characterization and genetic relatedness of the isolates were determined by polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST) and PCR-directed phylotyping. Plasmids were analyzed by conjugation, S1-PFGE, Southern blotting and PCR-based replicon typing (PBRT). The genetic environment of the bla KPC-2 gene was determined using PCR and sequencing. PCR analyses revealed that the E1 isolate carried the bla KPC-2, bla CMY-2, bla TEM-1, bla CTX-M-14, and qnrB2 genes and belonged to sequence type ST410, phylogenetic type A; the E2 isolate was assigned to ST131-B2 and carried the bla KPC-2, bla TEM-1, bla CTX-M-3, bla DHA-1, aac(6')-Ib-cr, and qnrS1 genes; while the E3 isolate was of ST648-D and possessed bla KPC-2, bla TEM-1, bla OXA-1, bla CTX-M-15, armA, and aac(6')-Ib-cr genes. PFGE demonstrated that each of the three KPC-2-producing E. coli isolates exhibited an individual XbaI patterns. The bla KPC-2 gene was located on plasmids of 60-140 kb with IncA/C, IncN, or non-typeable replicon types. The genetic environment of bla KPC-2 of the three strains was consistent with the genetic structure of bla KPC-2 on the plasmid pKP048.

  18. [Study on virulence factors associated with biofilm formation and phylogenetic groupings in Escherichia coli strains isolated from patients with cystitis].

    PubMed

    Tiba, Monique Ribeiro; Nogueira, Gustavo Prado; Leite, Domingos da Silva

    2009-01-01

    Escherichia coli samples isolated from female patients with cystitis were characterized with regard to the presence of virulence factors associated with biofilm formation and phylogenetic groupings. Polymerase chain reaction results demonstrated that all the samples were positive for the gene fimH (type 1 fimbriae), 91 for fliC (flagellins), 50 for papC (P fimbriae), 44 for kpsMTII (capsules) and 36 for flu (antigen 43). The results from assays to quantify the biofilm formation demonstrated that 44 samples produced biofilm on polystyrene microplates and 56 samples produced weak or no biofilm. We also confirmed that Escherichia coli samples were present in phylogenetic groups B2 and D.

  19. Subtyping Escherichia coli Virulence Genes Isolated from Feces of Beef Cattle and Clinical Cases in Alberta.

    PubMed

    Tostes, Renata; Goji, Noriko; Amoako, Kingsley; Chui, Linda; Kastelic, John; DeVinney, Rebekah; Stanford, Kim; Reuter, Tim

    2017-01-01

    Clinical outcomes of Shiga toxin (stx)-producing Escherichia coli infection are largely determined by virulence gene subtypes. This study used a polymerase chain reaction (PCR)-pyrosequencing assay to analyze single-nucleotide polymorphisms for subtyping three major virulence genes (stx1, stx2, eae) of pathogenic E. coli (O157, O26, O111, and O103) isolated from cattle over a 2-year interval (n = 465) and human clinical cases (n = 42) in western Canada. Most bovine isolates were PCR positive for at least one target virulence gene (367/465), whereas 100% of human isolates harbored eae in combination with at least one stx gene. Four Shiga toxin (1a, 2a, 2c, and 2e) and four eae (λ/γ1-eae, ɛ-eae, θ/γ2-eae, and β-eae) subtypes were identified in over 25 distinct virulence genotypes. Among cattle isolates, every serogroup, but O103, presented a dominant genotype (O157: stx1a+stx2a+λ/γ1-eae, O26: β-eae alone, and O111: stx1a+θ/γ2-eae). Similar patterns were found in human isolates, although it was not possible to establish a clear genotypic association between the two sources. Many O157 and non-O157 cattle isolates lacked stx genes; the absence was greater in non-O157 (75/258) and O157:non-H7 (19/40) than in O157:H7 strains (1/164). In addition, there was a greater diversity of virulence genotypes of E. coli isolated from cattle than those of human diseases, which could be due to sample characteristics (e.g., source and clinical condition). However, the majority of cattle strains had virulence profiles identical to those of clinical cases. Consequently, determining the presence of certain stx (stx1a and stx2a) and eae (λ/γ1-eae) subtypes known to cause human disease would be a valuable tool for risk assessment and prediction of disease outcome along the farm-to-fork continuum.

  20. Characterization of attaching and effacing Escherichia coli (AEEC) isolated from pigs and sheep

    PubMed Central

    Fröhlicher, Erik; Krause, Gladys; Zweifel, Claudio; Beutin, Lothar; Stephan, Roger

    2008-01-01

    Background Attaching and effacing Escherichia coli (AEEC) are characterized by their ability to cause attaching-and-effacing (A/E) lesions in the gut mucosa of human and animal hosts leading to diarrhoea. The genetic determinants for the production of A/E lesions are located on the locus of enterocyte effacement (LEE), a pathogenicity island that also contains the genes encoding intimin (eae). This study reports data on the occurrence of eae positive E. coli carried by healthy pigs and sheep at the point of slaughter, and on serotypes, intimin variants, and further virulence factors of isolated AEEC strains. Results Faecal samples from 198 finished pigs and 279 sheep were examined at slaughter. The proportion of eae positive samples was 89% for pigs and 55% for sheep. By colony dot-blot hybridization, AEEC were isolated from 50 and 53 randomly selected porcine and ovine samples and further characterized. Strains of the serotypes O2:H40, O3:H8 and O26:H11 were found in both pigs and sheep. In pigs O2:H40, O2:H49, O108:H9, O145:H28 and in sheep O2:H40, O26:H11, O70:H40, O146:H21 were the most prevalent serotypes among typable strains. Eleven different intimin types were detected, whereas γ2/θ was the most frequent, followed by β1, ε and γ1. All but two ovine strains tested negative for the genes encoding Shiga toxins. All strains tested negative for the bfpA gene and the EAF plasmid. EAST1 (astA) was present in 18 of the isolated strains. Conclusion Our data show that pigs and sheep are a source of serologically and genetically diverse intimin-harbouring E. coli strains. Most of the strains show characteristics of atypical enteropathogenic E. coli. Nevertheless, there are stx-negative AEEC strains belonging to serotypes and intimin types that are associated with classical enterohaemorrhagic E. coli strains (O26:H11, β1; O145:H28, γ1). PMID:18786265

  1. Uropathogenic Escherichia coli isolates with different virulence genes content exhibit similar pathologic influence on Vero cells.

    PubMed

    Obaid, Jamil M A S; Mansour, Samira R; Elshahedy, Mohammed S; Rabie, Tarik E; Azab, Adel M H

    2014-01-01

    Uropathogenic Escherichia coli are the major causative agent of urinary tract infection--they may simultaneously express a number of virulence factors to cause disease. The aim of this study was to investigate the relation between virulence factors content of fifteen UPEC isolates and their pathogenic potential. The isolates belonged to the five serotypes O78:K80, O114:K90, O142:K86, O164 and O157. Nine of the virulence factors have been explored, ibeA, pap, sfa/foc, cnfl, hly, fyuA, pil, ompT and traT. Virulence factors profiling of the isolates revealed a different content ranging from 22% to 100% of the virulence genes explored. The pathogenic capacity of all fifteen isolates when tested on Vero cells showed that the cytotoxicity for all tested strains on Vero cells was approximately equal and enhanced after growth in syncase broth, leading mainly to cell lysis. The toxic effects reduced slightly after heat treatment of the toxin, and greatly after formalin detoxification, but not all the deleterious effect was abolished. Endotoxin also has cytotoxic effects on Vero cells, but longer time is needed for cytolysis which is greatly diminished with formalin treatment. In conclusion, our study revealed that pathogenic strains of UPEC can exert their pathogenic effect on live cells or system with limited virulence factors gene content.

  2. Distribution of saa gene variants in verocytotoxigenic Escherichia coli isolated from cattle and food.

    PubMed

    Lucchesi, Paula M A; Krüger, Alejandra; Parma, Alberto E

    2006-04-01

    The pathogenesis of verocytotoxigenic Escherichia coli (VTEC) infection in humans is multifactorial, given that verocytotoxins are the principal virulence factor. Most strains causing serious diseases possess the eae gene that encodes the adhesin intimin, but its presence is not essential for virulence as some cases are caused by eae-negative strains. An autoagglutinating adhesin designated Saa was found in some eae-negative strains. This protein varies in size as a consequence of variation in the number of copies of a 37-aa repeat unit in the C-terminal region. Based on these findings, we designed PCR primers to amplify the region coding for these differences to detect saa gene variants present in VTEC strains isolated in Argentina from cattle and meat. The gene saa was detected in 36 (31.6%) eae-negative strains and 5 variants were found. Strains isolated from cattle possessed 4 saa variants, whereas 2 variants were present in isolates from meat. Saa variant 1 predominated (18 strains) and was distributed in strains isolated both from cattle and from meat. Our study revealed the existence of two novel saa variants, termed 4 and 5, which have a higher number of 111-bp repeats than saa genes previously studied.

  3. Characterization of antimicrobial resistance and integrons among Escherichia coli isolated from animal farms in Eastern China.

    PubMed

    Lu, Liming; Dai, Lei; Wang, Yang; Wu, Congming; Chen, Xia; Li, Lin; Qi, Yonghua; Xia, Lining; Shen, Jianzhong

    2010-01-01

    A total of 182 Escherichia coli isolates from animals, environment and workers of dairy cattle, swine and chicken farms in Shandong which locates in Eastern China, were investigated for antimicrobial resistance as well as prevalence and the transfer mechanisms of integrons. The results revealed isolates from swine and chicken farm exhibited high levels of resistance to antimicrobial agents. The positive rate of gene cassette of class 1 integron in dairy cattle, swine and chicken farms was 5%, 20% and 41.94%, respectively. Only four isolates possessed class 2 integron, all of which were from chicken farm. Nine distinct cassette arrays were detected and two novel gene cassette arrays yheSDelta-yheR-kefBDelta and chrADelta-sul1-qacEDelta1-orf5-aadA5-dfrA17 were identified in class 1 integron for the first time. Class 1 integrons were found to be located mostly in both chromosomal and conjugative plasmid through southern hybridization and conjugation. PFGE revealed clonal relatedness among the isolates from different sources, especially within the same farm. The results confirmed the antimicrobial resistance and prevalence of integrons were strongly associated with the selection pressure of antimicrobial agents, and resistance genes in animal farms were probably spread by both vertical and horizontal transfer.

  4. Identification of antibiotic-resistant Escherichia coli isolated from a municipal wastewater treatment plant.

    PubMed

    Zanotto, Carlo; Bissa, Massimiliano; Illiano, Elena; Mezzanotte, Valeria; Marazzi, Francesca; Turolla, Andrea; Antonelli, Manuela; De Giuli Morghen, Carlo; Radaelli, Antonia

    2016-12-01

    The emergence and diffusion of antibiotic-resistant bacteria has been a major public health problem for many years now. In this study, antibiotic-resistance of coliforms and Escherichia coli were investigated after their isolation from samples collected in a municipal wastewater treatment plant in the Milan area (Italy) along different points of the treatment sequence: inflow to biological treatment; outflow from biological treatment following rapid sand filtration; and outflow from peracetic acid disinfection. The presence of E. coli that showed resistance to ampicillin (AMP) and chloramphenicol (CAF), used as representative antibiotics for the efficacy against Gram-positive and Gram-negative bacteria, was evaluated. After determining E. coli survival using increasing AMP and CAF concentrations, specific single-resistant (AMP(R) or CAF(R)) and double-resistant (AMP(R)/CAF(R)) strains were identified among E. coli colonies, through amplification of the β-lactamase Tem-1 (bla) and acetyl-transferase catA1 (cat) gene sequences. While a limited number of CAF(R) bacteria was observed, most AMP(R) colonies showed the specific resistance genes to both antibiotics, which was mainly due to the presence of the bla gene sequence. The peracetic acid, used as disinfection agent, showed to be very effective in reducing bacteria at the negligible levels of less than 10 CFU/100 mL, compatible with those admitted for the irrigation use of treated waters. Copyright © 2016. Published by Elsevier Ltd.

  5. Evaluation of Prevalence, Homology and Immunogenicity of Dispersin among Enteroaggregative Escherichia coli Isolates from Iran

    PubMed Central

    Karam, Mohammad Reza Asadi; Rezaei, Ali Akbar; Siadat, Seyed Davar; Habibi, Mehri; Bouzari, Saeid

    2017-01-01

    Background: Diarrhea, caused by enteroaggregative Escherichia coli (EAEC), is an important infection leading toillness and death. Numerous virulent factors have been described in EAEC. However, their prevalence was highly variable among EAECs of distinct geographic locations. Studies have shown that dispersin (antiaggregation protein, aap) is one of the important and abundant virulent factors in EAEC. In this study, we aimed to determine the presence, conservation, and immunogenicity of aap gene in EAEC isolated from Iranian patients. Methods: PCR amplification of aap gene in the EAEC isolates was performed, and the aap gene was cloned in pBAD-gIIIA vector. The sequence of aap gene was analyzed using the ExPASy and BLAST tools. The expression of aap gene was performed in E. coli Top10, and expression confirmation was carried out by SDS-PAGE and Western-blot techniques. Rabbits were immunized with purified dispersin protein emulsified with Freund’s adjuvant. Sera were collected and examined for antibody response. Finally, in vitro efficacy of dispersin and anti-dispersin was evaluated. Results: The results of PCR showed the presence of aap gene in all of the EAEC isolates with significant homology. Finally, the significant difference between the levels of IgG response in dispersin-injected rabbits and control group was observed. Conclusion: Our results were in accordance with other studies that reported the presence of dispersin in the EAEC isolates with high conservation and immunogenicity. Hence, dispersin could be a promising candidate for any probable prevention against EAEC infections. PMID:27155019

  6. CTX-M-15 Extended-Spectrum β-Lactamase in a Shiga Toxin-Producing Escherichia coli Isolate of Serotype O111:H8

    PubMed Central

    Haenni, Marisa; Saras, Estelle; Auvray, Frédéric; Forest, Karine; Oswald, Eric; Madec, Jean-Yves

    2012-01-01

    We report the discovery of a CTX-M-15-producing Escherichia coli (STEC) of serogroup O111:H8, a major serotype responsible for human enterohemorrhagic Escherichia coli (EHEC) infections. In line with the recent CTX-M-15/O104:H4 E. coli outbreak, these data may reflect an accelerating spread of resistance to expanded-spectrum cephalosporins within the E. coli population, including STEC isolates. PMID:22156432

  7. Isolation and Characterization of NDM-Positive Escherichia coli from Municipal Wastewater in Jeddah, Saudi Arabia

    PubMed Central

    Mantilla-Calderon, David; Jumat, Muhammad Raihan; Wang, Tiannyu; Ganesan, Pugalenthi; Al-Jassim, Nada

    2016-01-01

    The emergence of resistance to last-resort antibiotics is a public health concern of global scale. Besides direct person-to-person propagation, environmental pathways might contribute to the dissemination of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Here, we describe the incidence of blaNDM-1, a gene conferring resistance to carbapenems, in the wastewater of the city of Jeddah, Saudi Arabia, over a 1-year period. blaNDM-1 was detected at concentrations ranging from 104 to 105 copies/m3 of untreated wastewater during the entire monitoring period. These results indicate the ubiquity and high incidence of blaNDM-1 in the local wastewater. To track the bacteria carrying blaNDM-1, we isolated Escherichia coli PI7, a strain of sequence type 101 (ST101), from wastewater around the Hajj event in October 2013. Genome sequencing of this strain revealed an extensive repertoire of ARGs as well as virulence and invasive traits. These traits were further confirmed by antibiotic resistance profiling and in vitro cell internalization in HeLa cell cultures. Given that this strain remains viable even after a certain duration in the sewerage, and that Jeddah lacks a robust sanitary infrastructure to fully capture all generated sewage, the presence of this bacterium in the untreated wastewater represents a potential hazard to the local public health. To the best of our knowledge, this is the first report of a blaNDM-1-positive E. coli strain isolated from a nonnosocomial environment in Saudi Arabia and may set a priority concern for the need to establish improved surveillance for carbapenem-resistant E. coli in the country and nearby regions. PMID:27324770

  8. Virulence determinants, phylogenetic groups and fluoroquinolone resistance in Escherichia coli isolated from cystitis and pyelonephritis.

    PubMed

    Ferjani, S; Saidani, M; Ennigrou, S; Hsairi, M; Ben Redjeb, S

    2012-10-01

    The aim of this study is to assess the relation between virulence genotype, phylogenetic group and susceptibility to fluoroquinolones and the urinary tract infection type including pyelonephritis and cystitis due to Escherichia coli. Between 2006 and 2007, 129 non-duplicate E. coli isolates from pyelonephritis (n=56) and cystitis (n=73) were prospectively collected. The antibiotic susceptibility was done by disk diffusion method. The phylogenetic groups, A, B1, B2 and D and 18 virulence genes were determined by multiplex PCR. Statistical analysis was done with the Pearson χ2 test, Mann-Whitney U-test, Kruskal-Wallis test and stepwise multivariable logistic regression analysis, P values below 0.05 were considered statistically significant. For the pyelonephritis group, sex ratio was 0.3, the median age for women was 30 years and for men it was 54 years. For the cystitis group, sex ratio was 0.4, the median age for women was 41.5 years and for men it was 67.8 years. Significant statistical correlations were found between pyelonephritis isolates and susceptibility to ciprofloxacin (P=4 10(-5)), papG allele II (P=2 10(-6)), hlyA (P=10(-03)), iroN (P=0.04), iha (P=0.03) and ompT (P=0.03) virulence genes, high virulence score (P=0.008) and B2 phylogenetic group (P=0.03). In multivariate logistic regression analysis, papG II as predictor of pyelonephritis, no correlation could be established for the cystitis group. Our findings argue for a direct link between pyelonephritis, virulence factors, susceptibility to fluroquinolones and B2 phylogenetic group among uropthogenic E. coli. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  9. ESBL-producing Escherichia coli and Klebsiella pneumoniae: The most prevalent clinical isolates obtained between 2005 and 2012 in Mexico.

    PubMed

    Barrios, Humberto; Garza-Ramos, Ulises; Mejia-Miranda, Ilse; Reyna-Flores, Fernando; Sánchez-Pérez, Alejandro; Mosqueda-García, Dalila; Silva-Sanchez, Jesus

    2017-07-21

    To identify the prevalence of ESBL genes in the principal group of Enterobacteriaceae causing nosocomial infections and to identify the phylogenetic group in Escherichia coli isolates. There were collected 1084 ESBL-producing Enterobacteriaceae isolates during 2005-2012 from adult patients from 14 hospitals and corresponding to eight states and five regions (SE, S, N, W and NW) in Mexico. The CTX-M-(CTX-M-1 group), SHV-, TLA- and GES-type ESBLs genes were screened. The respective alleles were determined in the most of ESBLs genes. In E. coli isolates selected were used to identify the phylogenetic group. The ESBL-producing Escherichia coli and Klebsiella pneumoniae corresponded the most prevalent clinical isolates. CTX-M-type ESBLs genes were the most common, followed by SHV-type, GES-type and the ESBLs TLA-1 gene. The allelic frequency showed to CTX-M-15 ESBL the most prevalent, followed by the SHV-12, SHV-5 and GES-1, GES-19 in the GES family. Among ESBL-producing E. coli isolates the phylogenetic groups A and D were the most common ones. The present study showed an epidemiological change in terms of bacterial species, placing E. coli as the most frequently isolated bacteria among ESBL-producing Enterobacteriaceae in Mexico, followed by K. pneumoniae. This frequency is accompanied by a high frequency of ESBL CTX-M-15. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

  10. The Molecular Epidemiology of Resistance in Cefotaximase-Producing Escherichia coli Clinical Isolates from Dublin, Ireland.

    PubMed

    Burke, Liam; Humphreys, Hilary; Fitzgerald-Hughes, Deirdre

    2016-10-01

    In view of continued high clinical prevalence of infections involving extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, this study sought to characterise the blaCTX-M genes, their associated mobile genetic elements and the integrons present in 100 ESBL-producing E. coli isolates collected in a Dublin hospital and associated community healthcare facilities. Polymerase chain reaction (PCR) mapping and sequencing was used to detect blaCTX-M alleles, their associated insertion sequences (ISs) and class 1 and 2 integrons in the collection. ESBL plasmids were characterised by PCR-based replicon typing and replicon sequence typing (RST). Cefotaximases were harboured by 94% of isolates (66 blaCTX-M-15, 8 blaCTX-M-14, 7 blaCTX-M-1, 4 blaCTX-M-3, 3 blaCTX-M-9, 2 blaCTX-M-27, 2 blaCTX-M-55, 1 blaCTX-M-32 and 1 blaCTX-M-2). An ISEcp1 promoter was linked to a group 1 blaCTX-M gene in 45% of isolates. A further 34% of isolates contained blaCTX-M-15 downstream of IS26, an arrangement typical of epidemic UK strain A. Class 1 integrons were found in 66% of isolates, most carrying trimethoprim/aminoglycoside resistance genes. CTX-M plasmids were primarily of multireplicon IncF or IncI1 type, but IncN and unidentified types were also found. Novel IncF RSTs F1:A-:B-, F45:A1:B-, F45:A4:B- and a novel IncI1 sequence type, ST159, were identified. CTX-M plasmids and integrons resembled those identified recently in animal isolates from Ireland and Western Europe. The molecular epidemiology of CTX-M-producing E. coli in Dublin suggests that horizontal spread of mobile genetic elements contributes to antimicrobial resistant human infections. Further investigations into whether animals or animal products represent an important local reservoir for these elements are warranted.

  11. Genetic characterization of Shiga toxin-producing Escherichia coli (STEC) and atypical enteropathogenic Escherichia coli (EPEC) isolates from goat's milk and goat farm environment.

    PubMed

    Álvarez-Suárez, María-Elena; Otero, Andrés; García-López, María-Luisa; Dahbi, Ghizlane; Blanco, Miguel; Mora, Azucena; Blanco, Jorge; Santos, Jesús A

    2016-11-07

    The aim of this study was to characterize a collection of 44 Shiga toxin-producing (STEC) and enteropathogenic Escherichia coli (EPEC) isolated from goat milk and goat farm environment. Of the 19 STEC isolates, five (26.3%) carried the stx1 gene, four (21.1%) the stx2 gene and 10 (52.6%) presented both stx genes. Six (31.6%) STEC strains were eae-positive and belonged to serotypes related to severe human disease (O157:H7 and O5:HNM). Another seven STEC strains were of serotype O146:H21 and three of serotype O166:H28, also linked to human disease. The STEC strains isolated from goat milk were of serotypes potentially pathogenic for humans. All the 25 EPEC isolates were considered atypical (aEPEC) and one aEPEC strain was of serotype O26:H11, a serotype frequently isolated in children with diarrhea. Multilocus sequence typing (MLST) was carried out with seven housekeeping genes and 23 sequence types (ST) were detected, 14 of them newly described. Twelve STs grouped STEC isolates and 11 STs grouped EPEC isolates. Genetic typing by pulsed field gel electrophoresis (PFGE) resulted in 38 patterns which grouped in 10 clusters. Well-defined groups were also observed for strains of pathogenic serotypes. In conclusion, strains of STEC and aEPEC belonging to serotypes related to severe human disease have been detected in goat milk and the goat farm environment. Ruminants are an important reservoir of STEC strains and the role of these animals as carriers of other pathogenic types of E. coli seems to be an emerging concern.

  12. Antimicrobial resistance in generic Escherichia coli isolated from swine fecal samples in 90 Alberta finishing farms

    PubMed Central

    Varga, Csaba; Rajíc, Andrijana; McFall, Margaret E.; Avery, Brent P.; Reid-Smith, Richard J.; Deckert, Anne; Checkley, Sylvia L.; McEwen, Scott A.

    2008-01-01

    The objective of this study was to determine the prevalence of antimicrobial resistance in generic Escherichia coli isolates obtained from 90 Alberta finisher swine farms. Up to 5 isolates were obtained from each of 269 pooled fecal samples and were classified as susceptible or resistant according to Clinical and Laboratory Standards Institute guidelines. Of the 1322 isolates, 166 (12.6%) were susceptible to all 15 antimicrobials. No resistance to amikacin, ceftiofur, ceftriaxone, or ciprofloxacin, antimicrobials of importance in human medicine, was observed. Relatively low frequencies of resistance were observed to gentamicin (1.1%), amoxicillin/clavulanic acid (0.7%), and cefoxitin (0.7%). Higher frequencies of resistance were observed for tetracycline (78.9%), sulfisoxazole (49.9%), streptomycin (49.6%), ampicillin (30.6%), chloramphenicol (17.6%), kanamycin (10%), and trimethoprim/sulfamethoxazole (6.4%). Among the isolates resistant to ≥ 2 antimicrobial classes, 20.8%, 20.6%, 18.2%, 7.0%, 1.8%, 0.2%, and 0.2% were resistant to 2, 3, 4, 5, 6, 7, and 8 antimicrobials, respectively. The most common multidrug-resistance patterns (resistance to ≥ 2 antimicrobial classes) were streptomycin-tetracycline (9.4%), streptomycin-sulfisoxazole-tetracycline (6.2%), and ampicillin-streptomycin-sulfisoxazole-tetracycline (6.1%). More clustering (higher intra-class correlation coefficients) in antimicrobial resistance was observed for isolates at the same visit than for isolates from different visits in the same farm, indicating that sampling more farms, testing fewer isolates per visits, and taking longer periods between visits may be appropriate and more efficient for a better understanding of potential shifts in resistance over time. PMID:18505207

  13. Virulence Genes in Expanded-Spectrum-Cephalosporin-Resistant and -Susceptible Escherichia coli Isolates from Treated and Untreated Chickens.

    PubMed

    Baron, S; Delannoy, S; Bougeard, S; Larvor, E; Jouy, E; Balan, O; Fach, P; Kempf, I

    2015-12-14

    This study investigated antimicrobial resistance, screened for the presence of virulence genes involved in intestinal infections, and determined phylogenetic groups of Escherichia coli isolates from untreated poultry and poultry treated with ceftiofur, an expanded-spectrum cephalosporin. Results show that none of the 76 isolates appeared to be Shiga toxin-producing E. coli or enteropathogenic E. coli. All isolates were negative for the major virulence factors/toxins tested (ehxA, cdt, heat-stable enterotoxin [ST], and heat-labile enterotoxin [LT]). The few virulence genes harbored in isolates generally did not correlate with isolate antimicrobial resistance or treatment status. However, some of the virulence genes were significantly associated with certain phylogenetic groups.

  14. [Genotypic characterization of toxigenic Escherichia coli isolated from pigs with postweaning diarrhea (PWD) and edema disease (ED)].

    PubMed

    Moredo, Fabiana A; Cappuccio, Javier A; Insarralde, Lucas; Perfumo, Carlos J; Quiroga, María A; Leotta, Gerardo A

    2012-01-01

    The purpose of this work was to characterize 47 Escherichia coli strains isolated from 32 pigs diagnosed with postweaning diarrhea and three pigs with edema disease by PCR. Forty two (95.5 %) of the strains isolated from diarrheic pigs were characterized as enterotoxigenic E. coli (ETEC) and 2 (4.5 %) as Shiga toxin-producing E. coli (STEC). Fourteen (33.3 %) ETEC strains were positive for est/estII/fedA genes. The most complex genotype was eltA/estI/faeG/aidA. Strains isolated from pigs with ED were classified as porcine STEC and were stx2e/aidA carriers. Eleven (25 %) strains carried the gene encoding adhesin protein AIDA-I. However, genes coding for F5, F6, F41, intimin and Paa were not detected. The development of vaccines generating antibodies against prevalent E. coli adhesins in Argentina could be useful for the prevention of PWD and ED.

  15. Characterization of Extended-Spectrum-β-Lactamases Produced by Escherichia coli Strains Isolated from Dogs in Poland.

    PubMed

    Rzewuska, Magdalena; Stefańska, Ilona; Kizerwetter-Swida, Magdalena; Chrobak-Cmiel, Dorota; Szczygielska, Paulina; Leśniak, Monika; Binek, Marian

    2015-01-01

    Escherichia coli is a common cause of infections in companion animals. In recent years the increasing prevalence of resistance to β-lactams, including extended-spectrum cephalosporins, antimicrobials frequently used in small animal veterinary practice, was observed in canine isolates of E. coli. The aim of this study was to detect and to characterize extended-spectrum β-lactamases (ESBLs) produced by E. coli isolated from diseased dogs in Poland. Four isolates out of 119 studied (3.4%) were ESBL-positive. They harbored the bla(SHV-12), bla(CTX-M-15), and bla(TEM-116) genes. This study provides the first report of the occurrence of ESBL-producing E. coli in dogs in Poland.

  16. Multiplicity of serogroups and adhesins in enteropathogenic and enterotoxigenic Escherichia coli isolated from acute diarrhea in Senegal.

    PubMed Central

    Darfeuille-Michaud, A; Forestier, C; Masseboeuf, R; Rich, C; M'Boup, S; Joly, B; Denis, F

    1987-01-01

    Escherichia coli strains were isolated from 228 children with diarrhea in Senegal from 1982 to 1984. Among these E. coli involved in cases of diarrhea, we found that 20.3% were enteropathogenic E. coli. Only 3.9% of the strains adhered to the brush borders of human intestinal enterocytes, and they belonged to different serotypes. All these adhesion-positive strains possessed genes encoding for the heat-stable enterotoxin, but their adhesive factors were different regarding serology with anti-colonization factor sera, hemagglutination patterns, electron microscopy structures, or major surface protein subunits. PMID:2885338

  17. Diarrheagenic Escherichia coli

    PubMed Central

    Nataro, James P.; Kaper, James B.

    1998-01-01

    Escherichia coli is the predominant nonpathogenic facultative flora of the human intestine. Some E. coli strains, however, have developed the ability to cause disease of the gastrointestinal, urinary, or central nervous system in even the most robust human hosts. Diarrheagenic strains of E. coli can be divided into at least six different categories with corresponding distinct pathogenic schemes. Taken together, these organisms probably represent the most common cause of pediatric diarrhea worldwide. Several distinct clinical syndromes accompany infection with diarrheagenic E. coli categories, including traveler’s diarrhea (enterotoxigenic E. coli), hemorrhagic colitis and hemolytic-uremic syndrome (enterohemorrhagic E. coli), persistent diarrhea (enteroaggregative E. coli), and watery diarrhea of infants (enteropathogenic E. coli). This review discusses the current level of understanding of the pathogenesis of the diarrheagenic E. coli strains and describes how their pathogenic schemes underlie the clinical manifestations, diagnostic approach, and epidemiologic investigation of these important pathogens. PMID:9457432

  18. Incidence of diarrhoeagenic Escherichia coli isolated from young children with diarrhoea in the west of Iran.

    PubMed

    Alikhani, Mohammad Yousef; Sedighi, Iraj; Zamani, Alireza; Aslani, Mohammad Mehdi; Sadrosadat, Taravat

    2012-09-01

    Diarrhoeagenic Escherichia coli (DEC) represents a main group of enteric pathogens that cause human diarrhoea. Because it is not simply distinguished from normal flora by simple laboratory methods, modern molecular diagnostic assays are necessary. Although it is neither necessary nor applicable to perform PCR for all patients, it is of many advantages to verify the prevalence of DEC in different areas by this method. Knowing the prevalence of DEC in an area, we can focus on few pathogens and narrow our antimicrobial treatment. The aim of this study is to evaluate the contribution of the different DEC categories in children diarrhoea in the west of Iran.The stool specimens of 251 children with diarrhoea were collected from June to September 2007. Polymerase chain reaction (PCR) was performed to determine the presence of enteropathogenic (EPEC), enterotoxigenic (ETEC), entero-invasive (EIEC), Shiga toxin-producing (STEC) and entero-aggregative (EAEC) strains. ETEC strains were isolated from 13 and EAEC strains from 16 children. STEC was detected in 7 children, and no EIEC was isolated. Finally, EPEC strains were isolated in 41 cases. EAEC and EPEC are the most frequent DECs in children less than 10 years of age in West of Iran.

  19. Association of Antibiotic Resistance in Agricultural Escherichia coli Isolates with Attachment to Quartz▿

    PubMed Central

    Liu, Ping; Soupir, Michelle L.; Zwonitzer, Martha; Huss, Bridgette; Jarboe, Laura R.

    2011-01-01

    Surface water can be contaminated by bacteria from various sources, including manure from agricultural facilities. Attachment of these bacteria to soil and organic particles contributes to their transport through the environment, though the mechanism of attachment is unknown. As bacterial attachment to human tissues is known to be correlated with antibiotic resistance, we have investigated here the relationship between bacterial attachment to environmental particles and antibiotic resistance in agricultural isolates. We evaluated 203 Escherichia coli isolates collected from swine facilities for attachment to quartz, resistance to 13 antibiotics, and the presence of genes encoding 13 attachment factors. The genes encoding type I, EcpA, P pili, and Ag43 were detected, though none was significantly related to attachment. Quartz attachment was positively and significantly (P < 0.0038) related to combined resistance to amoxicillin/streptomycin/tetracycline/sulfamethazine/tylosin/chlortetracycline and negatively and significantly (P < 0.0038) related to combined resistance to nalidixic acid/kanamycin/neomycin. These results provide clear evidence for a link between antibiotic resistance and attachment to quartz in agricultural isolates. We propose that this may be due to encoding by the responsible genes on a mobile genetic element. Further exploration of the relationship between antibiotic resistance and attachment to environmental particles will improve the understanding and modeling of environmental transport processes, with the goal of preventing human exposure to antibiotic-resistant or virulent microorganisms. PMID:21821756

  20. Diffusely adherent Escherichia coli strains isolated from children and adults constitute two different populations

    PubMed Central

    2013-01-01

    Background Diffusely adherent Escherichia coli (DAEC) have been considered a diarrheagenic category of E. coli for which several potential virulence factors have been described in the last few years. Despite this, epidemiological studies involving DAEC have shown inconsistent results. In this work, two different collections of DAEC possessing Afa/Dr genes, from children and adults, were studied regarding characteristics potentially associated to virulence. Results DAEC strains were recovered in similar frequencies from diarrheic and asymptomatic children, and more frequently from adults with diarrhea (P < 0.01) than from asymptomatic adults. Association with diarrhea (P < 0.05) was found for SAT-positive strains recovered from children and for curli-positive strains recovered from adults. Mixed biofilms involving DAEC and a Citrobacter freundii strain have shown an improved ability to form biofilms in relation to the monocultures. Control strains have shown a greater diversity of Afa/Dr adhesins and higher frequencies of cellulose, TTSS, biofilm formation and induction of IL-8 secretion than strains from cases of diarrhea in children. Conclusions DAEC strains possessing Afa/Dr genes isolated from children and adults represent two different bacterial populations. DAEC strains carrying genes associated to virulence can be found as part of the normal microbiota present in asymptomatic children. PMID:23374248

  1. Isolation of genes conferring salt tolerance from Piriformospora indica by random overexpression in Escherichia coli.

    PubMed

    Gahlot, Sunayna; Joshi, Amita; Singh, Pratap; Tuteja, Renu; Dua, Meenakshi; Jogawat, Abhimanyu; Kumar, Manoj; Raj, Sumit; Dayaman, Vikram; Johri, Atul Kumar; Tuteja, Narendra

    2015-08-01

    Piriformospora indica, a root endophytic fungus identified in the Indian Thar desert, colonizes the roots of plants and provides resistance towards biotic stress as well as tolerance to abiotic stress in the plants. Despite its positive impact on the host, little is known about the P. indica genes that are involved in salt stress tolerance. Therefore this study was conducted to identify and isolate high salinity-tolerance genes from P. indica. Thirty-six salinity-tolerance genes were obtained by functional screening, based on random over expression of a P. indica cDNA library in Escherichia coli grown on medium supplemented with 0.6 M NaCl. The salinity tolerance conferred by these 36 genes in bacteria was further confirmed by using another strain of E. coli (DH5α) transformants. However when the expression of these 36 genes was analysed in P. indica using quantitative RT-PCR, we found only six genes were up-regulated by salt stress. These six genes are involved in different cellular processes, such as metabolism, energy and biosynthetic processes, DNA repair, regulation of protein turnover, transport and salt stress tolerance. This work presents the basis for further molecular analyses of the mechanisms of salt tolerance in P. indica and for the use of this endophyte to confer salt tolerance to plants.

  2. Prevalence of Enteropathogenic Escherichia coli Isolated from Chhana Based Indian Sweets in Relation to Public Health.

    PubMed

    Maity, T K; Kumar, Rakesh; Misra, A K

    2010-10-01

    Chhana based milk products viz. rossogolla, kanchagolla,narampak sandesh and karapak sandesh are very popular in eastern part of India and gaining popularity in other parts of the country. A wide variation in manufacture method, microbial quality and shelf-life of these traditional milk products were observed by previous research. The aim of the present study was to determine the prevalence of contamination of chhana based milk products available in Kolkata city with Enteropathogenic Escherichia coli (EPEC) serogroups. Random samples of different chhana based milk products were collected from different parts of Kolkata city in aseptic condition, cultured in selective media and examined for biochemical tests. Among 240 samples, E. coli was isolated from 67 (27.91%) of them. Potential EPEC was present in 52 samples (21.66%) and 55 of the isolates were EPEC. Eleven serogroups were identified viz. O26, O55, O111, O119, O114, O125, O142, O86, O126, O127, O128. Among all these serogroups, O55 (23.66%) was the most prevalent. Though recent studies on virulence factors indicate that not all strains serologically classified as EPEC are able to attaching/effacing lesion, it is believed that the isolation of EPEC serogroups from chhana based milk products represent a potential risk for public health particularly children, as well as an indicative of the presence of other enteropathogens. Considering the public health importance of sweetmeat consumers, the product should be prepared hygienically reducing the microbial load present in it. The result indicates that strict preventive measures should be adopted to ensure contamination free sweetmeats for the safety of the consumers.

  3. Isolation and characterization of an Escherichia coli strain exhibiting partial tolerance to quinolones.

    PubMed Central

    Wolfson, J S; Hooper, D C; Shih, D J; McHugh, G L; Swartz, M N

    1989-01-01

    Quinolone antimicrobial agents rapidly kill bacteria by largely unknown mechanisms. To study this phenomenon, a strain of Escherichia coli inhibited but inefficiently killed by (i.e., partially tolerant to) norfloxacin was isolated and characterized. E. coli KL16 (norfloxacin MIC, 0.10 microgram/ml; MBC, 0.20 microgram/ml) was mutagenized with nitrosoguanidine and cyclically exposed to 3 micrograms of norfloxacin per ml. After five cycles, a bacterial strain (DS1) which was killed 1,000-fold less than KL16 during 3 h of drug exposure was isolated. The MIC and MBC of norfloxacin for DS1 were 0.20 and 1.5 micrograms/ml, respectively. Over a range of norfloxacin concentrations, DS1 was killed 2 to 4 orders of magnitude less than KL16. DS1 grew more slowly than KL16 but after normalization for growth rate was killed four times less rapidly than KL16 at drug concentrations 10-fold higher than respective MICs. DS1 and KL16 cells filamented similarly upon exposure to norfloxacin. DS1 exhibited tolerance to other DNA gyrase A subunit antagonists (ofloxacin and ciprofloxacin) and DNA gyrase B subunit antagonists (novobiocin and coumermycin) but not to the aminoglycoside gentamicin, suggesting involvement of DNA gyrase. DS1 also appeared to be minimally tolerant to the beta-lactam cefoxitin. DS1 exhibited increased susceptibility to the mutagen methyl methanesulfonate, implying a defect in DNA repair. This report describes the first use of quinolone enrichment for isolation of a bacterial strain partially tolerant to quinolones. The study of defects in such tolerant strains offers an approach to an increased understanding of the mechanisms of bacterial killing by quinolones. PMID:2665642

  4. Characterization of integrons-mediated antimicrobial resistance among Escherichia coli strains isolated from bovine mastitis.

    PubMed

    Wang, Gui-Qin; Wu, Cong-Ming; Du, Xiang-Dang; Shen, Zhang-Qi; Song, Li-Hua; Chen, Xia; Shen, Jian-Zhong

    2008-02-05

    To assess the prevalence of antimicrobial resistance and class I integrons in Escherichia coli strains (n=58) isolated from bovine mastitis in Inner Mongolia, antimicrobial susceptibility and the presence of various types of integrons were characterized. Most isolates were susceptible to amikacin, colistin, ceftazidime, gentamicin and kanamycin, while those also exhibited high resistant incidence rates to ampicillin, amoxicillin, sulfadiazine and sulfamethoxydiazine. The integrase gene of integrons was amplified by PCR using degenerate primers. The integrons were confirmed by restriction fragment length polymorphism (RFLP) analysis of positive PCR products. Neither class II nor class III integron was detected, while 56.90% (n=33) of the isolates were positive for the presence of intI1 gene. Sequencing analysis of gene cassettes revealed that seven gene cassettes were found, which encoded resistance to trimethoprim (dfrA1 and dfrA17), aminoglycosides (aacA4, aadA1 and aadA5) and chloramphenicol (catB3), respectively. Of them, the gene cassette array dfrA17-aadA5 was found most prevalent (62.96%). The percentage of positive-integron among the isolates whose resistant profile was relatively broad (n> or =7) is 100.00%, while the one in narrow-profile isolates (n=2-6) is 30.56%. The correlation analysis revealed the incidence of integrons among the isolates were highly related to the resistant profile, indicating integrons play an important role in the dissemination and spread of the antimicrobial resistant strains.

  5. Patterns of loss of enterotoxigenicity by Escherichia coli isolated from adults with diarrhea: suggestive evidence for an interrelationship with serotype.

    PubMed Central

    Evans, D J; Evans, D G; DuPont, H L; Orskov, F; Orskov, I

    1977-01-01

    Enterotoxigenic Escherichia coli isolates obtained in Mexico from adult subjects with diarrhea and from healthy controls were examined for the production of heat-stable enterotoxin (ST) and heat-labile enterotoxin (LT) after serial passage in the laboratory. Isolates were found to be either stable for the production of ST and LT or unstable with respect to ST, LT, or both. Unilateral loss of either ST or LT production allowed classification of E. coli isolates into four groups according to stability/instability of enterotoxin production. Fewer serotypes, with more representative isolates, were in group I (stable) than in group IV (completely unstable). Isolates from Dacca, Bangladesh, could be similarly classified into stability groups. There is an apparent relationship between serotype, stability of enterotoxin production, particularly LT, and isolation from diarrhea cases as opposed to isolation from healthy controls. PMID:328392

  6. Phenotypic characterization and genomic DNA polymorphisms of Escherichia coli strains isolated as the sole micro-organism from vaginal infections.

    PubMed

    Lobos, Olga; Padilla, Carlos

    2009-03-01

    Vaginal infections such as vulvovaginal candiadiasis, trichomoniasis and bacterial vaginosis are common worldwide. Accurate diagnosis and prescription of appropriate treatments are important since these infections are linked to adverse outcomes for women during pregnancy and for newborns. Several aetiological agents are responsible for these infectious diseases; however, the presence of Escherichia coli in these infections is controversial. Thus, it is important to identify some phenotypic and genotypic properties of E. coli strains isolated from vaginal infections. Forty-six E. coli strains isolated from vaginal fluid as the sole micro-organism, and 20 other E. coli strains isolated from other samples (urinary tract infections, otitis and septicaemia) were analysed by several phenotypic tests. In addition, genotypic features were studied by RAPD-PCR techniques. Biochemical tests showed that the E. coli strains isolated from vaginal fluid could be grouped into a single cluster which is subdivided into two phenogroups. Analysis of the dendrogram based on fragment length polymorphisms of genomic DNA indicated that E. coli isolates from vaginal infections form a single cluster with two subdivisions. Further studies are needed to analyse the molecular structure and virulence characteristics of these E. coli strains in order to determine their potential role in vaginal infections.

  7. Pathogenic Escherichia coli

    USDA-ARS?s Scientific Manuscript database

    Escherichia coli, a member of the Enterobacteriaceae family, is a part of the normal flora of the intestinal tract of humans and a variety of animals. E. coli strains are classified on the basis of antigenic differences in two surface components (serotyping), the somatic antigen (O) of the lipopoly...

  8. PATHOGENIC ESCHERICHIA COLI

    EPA Science Inventory

    Escherichia coli is a bacterial species which inhabits the gastrointestinal tract of man and warm-blooded animals. Because of the ubiquity of this bacterium in the intestinal flora, it serves as an important indicator organism of fecal contamination. E. coli, aside from serving a...

  9. 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.

  10. Evaluation of the susceptibility profiles, genetic similarity and presence of qnr gene in Escherichia coli resistant to ciprofloxacin isolated in Brazilian hospitals.

    PubMed

    Pereira, Andrea S; Andrade, Soraya S; Monteiro, Jussimara; Sader, Helio S; Pignatari, Antonio C C; Gales, Ana C

    2007-02-01

    Increasing quinolone resistance has been reported worldwide, mainly among clinical isolates of Escherichia coli. The objectives of this study were to determine the susceptibility profile, the genetic relatedness, and the prevalence of the qnr gene among ciprofloxacin-resistant Escherichia coli isolated from distinct Brazilian hospitals. A total of 144 ciprofloxacin-resistant Escherichia coli were isolated from 17 Brazilian hospitals between January/2002 and June/2003. The antimicrobial susceptibility testing was performed by microdilution according to NCCLS. The presence of the qnr gene was initially screened by colony blotting, and then confirmed by PCR followed by DNA sequencing. Ninety-five urinary ciprofloxacin-resistant Escherichia coli were further selected for molecular typing by pulsed-field gel electrophoresis (PFGE). Imipenem and meropenem showed the highest susceptibility rates (100.0% for both compounds) followed by amikacin (91.0%) and piperacillin/tazobactan (84.8%). A single ciprofloxacin-resistant Escherichia coli isolate was positive for qnr among the 144 ciprofloxacin-resistant Escherichia coli. Forty-six PFGE patterns were observed among the 95 ciprofloxacin-resistant Escherichia coli type. This study shows that therapeutic options are limited for treatment of ciprofloxacin-resistant Escherichia coli due to the presence of additional mechanisms of antimicrobial resistance, such as ESBL production. The qnr gene was uncommon among ciprofloxacin-resistant Escherichia coli clinical isolates, but its identification might indicate the emergence of this mechanism of quinolone resistance in Brazil. The great genomic variability found among the ciprofloxacin-resistant Escherichia coli highlights the importance of the appropriate use of quinolone to restrict the selection of resistant isolates.

  11. Transferability of antimicrobial resistance from multidrug-resistant Escherichia coli isolated from cattle in the United States to Escherichia coli and Salmonella Newport recipients

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to evaluate conjugative transfer of cephalosporin resistance among (n=100) strains of multi-drug resistant Escherichia coli (MDRE) to Salmonella Newport and E. coli DH5-alpha recipients. To accomplish this, phenotypic and genotypic profiles were determined for MDRE, ...

  12. Isolation and characterization of Escherichia coli pili from diverse clinical sources.

    PubMed Central

    Salit, I E; Vavougios, J; Hofmann, T

    1983-01-01

    Bacteria which attach to different mucous membranes should have differing specificities of adherence in vitro. Human Escherichia coli isolates from blood and urine (pathogens) and from stool and throat (commensals) were characterized as to the patterns of hemagglutination (HA), as well as the structure and function of their pili. Bacterial HA was done in microtiter plates and on slides after bacterial growth in broth or agar. Human erythrocytes were agglutinated by 95% of the pathogens and 65 to 70% of the commensals grown in broth or agar. Mannose-resistant HA was characteristically caused by pathogens, and commensals characteristically caused mannose-sensitive HA of guinea pig cells. Strains often had both mannose-resistant and mannose-sensitive reactions, or even a mannose-paradoxical reaction. Pathogens more often caused HA, but titers were lower than those for commensals. Slide HA was less sensitive than the microtiter method. All isolates were piliated. Commensals also had more pili than pathogens when grown in broth (117.8 versus 38.3 pili per bacterium), but pathogens had more pili after growth on agar (32.1 versus 8.1 pili per bacterium). Isolates causing high-titer HA had large numbers of pili (greater than 85 pili per bacterium), but some well-piliated strains were non-hemagglutinating. Pili were purified from seven E. coli strains from different sites of isolation and with different erythrocyte-binding specificity. Pili usually migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, more than one type of pilus could be copurified from some strains since there were two or more bands after separation in octyl-glucoside and two different amino terminal sequences. Protein sequencing was done on five different pili: four resembled type 1 pili and one was a P fimbria. The type 1-like pili (strains 2239 and 9353) had an initial variable sequence of 1 to 5 residues, followed by a common region of 21 residues. The P

  13. Characterisation of quinolone-resistant Escherichia coli of 1997 and 2005 isolates from poultry in Mexico.

    PubMed

    Del Rio-Avila, C; Rosario, C; Arroyo-Escalante, S; Carrillo-Casas, E M; Díaz-Aparicio, E; Suarez-Güemes, F; Silva-Sanchez, J; Xicohtencatl-Cortes, J; Maravilla, P; Hernández-Castro, R

    2016-08-01

    Forty-two enrofloxacin-resistant Escherichia coli strains isolated from eggs and first-week mortality associated with yolk sac infection of two vertically integrated poultry companies of Central Mexico in 1997 and 2005 were characterised. E. coli resistance to 19 antibiotics was determined, as well as the minimum inhibitory concentrations (broth dilution) for ciprofloxacin. The presence of gyrA,B, parC,E chromosomal point mutations, qnrA,B,S plasmid genes and the aminoglycoside acetyltransferase aac(6')-Ib-cr were determined by PCR and sequencing. Resistance to ampicillin (95%), piperacillin (95%), gatifloxacin (95%), levofloxacin (95%), ampicillin/sulbactam (90%), cefazolin (85%), trimethoprim/sulfamethoxazole (80%), amoxicillin/clavulanic acid (80%), aztreonam (80%), cefepime (80%), cefotaxime (80%), ceftazidime (80%), ceftriaxone (80%) and cefoxitin (75%) was high in the 2005 strains and 19 (95%) strains were resistant to 7 or more antimicrobials. The strains from 1997 expressed high rates of resistance only to the fluoroquinolones and 4 strains (18%) expressed resistance to 7 or more antimicrobials. All strains had a gyrA mutation (Ser83Leu) and a parC mutation (Ser80Ile or Ser80Arg) and 41 (97.6%) strains had a second gyrA mutation (Asp87Asn, Asp87Tyr or Asp87Gly). Only two (4.7%) strains had a parE mutation (Ser458Ala). A total of 10 strains were positive for the aac(6')-Ib wild-type gene, 6 strains for the aac(6')-Ib-cr variant and 6 strains possessed both the wild type and the variant. No gyrB mutations or qnrA,B,S genes were detected. This is the first report in Latin America of chromosomal and plasmid quinolone resistance genes in E. coli strains recovered from poultry.

  14. Virulence and plasmidic resistance determinants of Escherichia coli isolated from municipal and hospital wastewater treatment plants.

    PubMed

    Calhau, Vera; Mendes, Catarina; Pena, Angelina; Mendonça, Nuno; Da Silva, Gabriela Jorge

    2015-06-01

    Escherichia coli is simultaneously an indicator of water contamination and a human pathogen. This study aimed to characterize the virulence and resistance of E. coli from municipal and hospital wastewater treatment plants (WWTPs) in central Portugal. From a total of 193 isolates showing reduced susceptibility to cefotaxime and/or nalidixic acid, 20 E. coli with genetically distinct fingerprint profiles were selected and characterized. Resistance to antimicrobials was determined using the disc diffusion method. Extended spectrum β-lactamase and plasmid-mediated quinolone resistance genes, phylogroups, pathogenicity islands (PAIs) and virulence genes were screened by polymerase chain reaction (PCR). CTX-M producers were typed by multilocus sequence typing. Resistance to beta-lactams was associated with the presence of bla(TEM), bla(SHV), bla(CTX-M-15) and bla(CTX-M-32). Plasmid-mediated quinolone resistance was associated with qnrA, qnrS and aac(6')-Ib-cr. Aminoglycoside resistance and multidrug-resistant phenotypes were also detected. PAI IV(536), PAI II(CFT073), PAI II(536) and PAI I(CFT073), and uropathogenic genes iutA, papAH and sfa/foc were detected. With regard to the clinical ST131 clone, it carried bla(CTX-M-15), blaTEM-type, qnrS and aac(6')-lb-cr; IncF and IncP plasmids, and virulence factors PAI IV(536), PAI I(CFT073), PAI II(CFT073), iutA, sfa/foc and papAH were identified in the effluent of a hospital plant. WWTPs contribute to the dissemination of virulent and resistant bacteria in water ecosystems, constituting an environmental and public health risk.

  15. Genotypic Characterization of Egypt Enterotoxigenic Escherichia coli Isolates Expressing Coli Surface Antigen 6

    DTIC Science & Technology

    2013-02-01

    recovered in August 1995 from six different children in two villages in Abu Homos. This cluster might represent an outbreak among the children in Abu...CS6 populate 15 of these lineages, indicating widespread genomic heterogeneity. PFGE has also been shown to be useful for outbreak [52,53] and non... outbreak /surveillance of E. coli [54, 55]. In this study we selected PFGE as the method for phylogenetic analysis, in part to create a database of

  16. Antimicrobial Resistance Profiles in Escherichia coli O157 Isolates from Northern Colorado Dairies.

    PubMed

    McConnel, Craig S; Stenkamp-Strahm, Chloe M; Rao, Sangeeta; Linke, Lyndsey M; Magnuson, Roberta J; Hyatt, Doreene R

    2016-03-01

    Escherichia coli O157 (EcO157) infections can lead to serious disease and death in humans. Although the ecology of EcO157 is complex, ruminant animals serve as an important reservoir for human infection. Dairy cattle are unique because they may be a source of contamination for milk, meat, and manure-fertilized crops. Foodborne dairy pathogens such as EcO157 are of primary importance to public health. Antimicrobial resistance (AMR) is a complex phenomenon that complicates the treatment of serious bacterial infections and is of increasing concern. In the face of recommended use restrictions for antimicrobial agents in livestock operations, current AMR patterns in known foodborne pathogens should be documented. The objective of this study was to document AMR patterns in EcO157 isolates from dairies in northern Colorado using antimicrobial agents commonly found on dairies and representative of medically important antimicrobial drug classes. Seventy-five EcO157 isolates were recovered from three dairies. Six isolates were resistant to at least 1 of the 10 tested antimicrobial agents: four were resistant to streptomycin, sulfisoxazole, and tetracycline; one was resistant to streptomycin and tetracycline; and one was resistant to only tetracycline. All resistant isolates were from a single dairy. Overall, a low prevalence (8%) of AMR was observed among the 75 EcO157 isolates. No significant effects on AMR profiles due to virulence genes, parity, or previous antimicrobial treatments within the current lactation period were detected. The results of this study provide background information for future comparative studies investigating AMR trends. Future studies should include more participating farms and more samples and should control for potential confounding factors of AMR that may underlie individual farm variation.

  17. Occurrence of plasmid-mediated quinolone resistance and virulence genes in avian Escherichia coli isolates from Algeria.

    PubMed

    Laarem, Meradi; Barguigua, Abouddihaj; Nayme, Kaotar; Akila, Abdi; Zerouali, Khalid; El Mdaghri, Naima; Timinouni, Mohammed

    2017-02-28

    The emergence and spread of quinolone-resistant Escherichia coli in poultry products puts consumers at risk of exposure to the strains of E. coli that resist antibiotic treatment. The objective of this study was to define the prevalence and virulence potential of poultry-associated nalidixic acid (NAL)-resistant E. coli in the Annaba city, Algeria. In total, 33 samples of retail chicken meat were purchased from various butcher shops and examined for bacterial contamination with NAL-resistant E. coli. These isolates were subjected to antimicrobial susceptibility testing and were also investigated for the presence of plasmid-mediated quinolone resistance (PMQR) genes and virulence genes using conventional polymerase chain reaction (PCR) and DNA sequencing. Phylogenetic grouping of the NAL-resistant E. coli isolates was determined by the conventional multiplex PCR method. Twenty-nine (87.8%) products yielded NAL-resistant E. coli. Antibiograms revealed that 96.55% of NAL-resistant E. coli isolates were multidrug resistant (MDR). Resistance was most frequently observed against sulfamethoxazole-trimethoprim (96.6%), tetracycline (96.6%), ciprofloxacin (72%), and amoxicillin (65.5%). Group A was the most prevalent phylogenetic group, followed by groups D, B1, and B2. The PMQR determinants were detected in three isolates with qnrB72 and qnrS1 type identified. Four (13.8%) isolates carried one of the Shiga toxin E. coli-associated genes stx1, stx2, and ehxA alleles. The high prevalence of NAL-resistant E. coli isolated from retail chicken meat with detection of MDR E. coli harboring Shiga toxin genes in this study gives a warning signal for possible occurrence of foodborne infections with failure in antibiotic treatment.

  18. 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.

  19. 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.

  20. Comparative Study of Virulence Traits of Escherichia coli Clinical Isolates Causing Early and Late Neonatal Sepsis▿

    PubMed Central

    Soto, S. M.; Bosch, J.; Jimenez de Anta, M. T.; Vila, J.

    2008-01-01

    Neonatal meningitis and septicemia caused by Escherichia coli are still major health problems in industrialized countries. Forty-seven E. coli strains causing neonatal sepsis were analyzed. Twenty-two and 25 strains caused early (detected from 0 to 3 days after birth) and late (detected from 4 to 28 days after birth) infections, respectively. Only the ibeA gene was significantly more prevalent in the strains causing early infections. PMID:18160454

  1. Expression and Characterization of Flagella in Nonmotile Enteroinvasive Escherichia coli Isolated from Diarrhea Cases

    PubMed Central

    Andrade, Agda; Girón, Jorge A.; Amhaz, Juliana M. K.; Trabulsi, Luiz R.; Martinez, Marina B.

    2002-01-01

    We report that enteroinvasive Escherichia coli (EIEC) serotypes considered to be nonmotile produce an unusually large (77 kDa) flagellin that is assembled into functional flagellum filaments that allow the bacteria to swim in modified motility agar. The EIEC flagellin showed N-terminal identity to most common enterobacterial flagellins, especially those of the E. coli H7 serotype. These data are important in terms of the epidemiology, evolution, and biology of EIEC. PMID:12228323

  2. Genomic Comparison of Escherichia coli K1 Strains Isolated from the Cerebrospinal Fluid of Patients with Meningitis †

    PubMed Central

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

    2006-01-01

    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. PMID:16552050

  3. Antigen Detection in Enteropathogenic Escherichia coli Using Secretory Immunoglobulin A Antibodies Isolated from Human Breast Milk

    PubMed Central

    Manjarrez-Hernandez, H. A.; Gavilanes-Parra, S.; Chavez-Berrocal, E.; Navarro-Ocaña, A.; Cravioto, A.

    2000-01-01

    Enteropathogenic Escherichia coli (EPEC) produces a characteristic attaching and effacing (A/E) lesion in the small intestines of infected children. The immune response to EPEC infection remains poorly characterized. The molecular targets that elicit protective immunity against EPEC disease are unknown. In this study protein antigens from EPEC were identified using secretory immunoglobulin A (sIgA) antibodies isolated from milk from Mexican women by Western blot analysis. Purified sIgA antibodies, which inhibit the adherence of EPEC to cells, reacted to many EPEC proteins, the most prominent of which were intimin (a 94-kDa outer membrane protein) and two unknown proteins with apparent molecular masses of 80 and 70 kDa. A culture supernatant protein of 110 kDa also reacted strongly with the sIgA antibodies. The molecular size of this protein and its reactivity with specific anti-EspC antiserum suggest that it is EPEC-secreted protein C (EspC). These EPEC surface protein antigens were consistently recognized by all the different sIgA samples obtained from 15 women. Screening of clinical isolates of various O serogroups from cases of severe infantile diarrhea revealed that all EPEC strains able to produce the A/E lesion showed expression of intimin and the 80- and 70-kDa proteins. Such proteins reacted strongly with the purified sIgA pool. Moreover, nonvirulent E. coli strains were unable to generate a sIgA response. The immunogenic capacities of the 80- and 70-kDa proteins as virulence antigens have not been previously reported. The strong sIgA response to intimin and the 80- and 70-kDa proteins obtained in this study indicates that such antigens stimulate intestinal immune responses and may elicit protective immunity against EPEC disease. PMID:10948121

  4. Chromatographic methods for the isolation of, and refolding of proteins from, Escherichia coli inclusion bodies.

    PubMed

    Gu, Zhenyu; Weidenhaupt, Marianne; Ivanova, Natalia; Pavlov, Michail; Xu, Bingze; Su, Zhi-Guo; Janson, Jan-Christer

    2002-06-01

    New methods for the chromatographic isolation of inclusion bodies directly from crude Escherichia coli homogenates and for the refolding of denatured protein are presented. The traditional method of differential centrifugation for the isolation of purified inclusion bodies is replaced by a single gel-filtration step. The principle is that the exclusion limit of the gel particles is chosen such that only the inclusion bodies are excluded, i.e., all other components of the crude homogenate penetrate the gel under the conditions selected. In the novel column refolding process, a decreasing gradient of denaturant (urea or Gu-HCl), combined with an increasing pH gradient, is introduced into a gel-filtration column packed with a gel medium that has an exclusion limit lower than the molecular mass of the protein to be refolded. A limited sample volume of the protein, dissolved in the highest denaturant concentration at the lowest pH of the selected gradient combination, is applied to the column. During the course of elution, the zone of denatured protein moves down the column at a speed approximately threefold higher than that of the denaturant. This means that the protein sample will gradually pass through areas of increasingly lower denaturant concentrations and higher pH, which promotes refolding into the native conformation. The shape and slope of the gradients, as well as the flow rate, will influence the refolding rate and can be adjusted for different protein samples. The principle is illustrated using a denatured recombinant scFv fusion protein obtained from E. coli inclusion bodies.

  5. Antimicrobial Susceptibility of Escherichia coli Strains Isolated from Alouatta spp. Feces to Essential Oils

    PubMed Central

    Carregaro, Adriano Bonfim; Santurio, Deise Flores; de Sá, Mariangela Facco; Santurio, Janio Moraes; Alves, Sydney Hartz

    2016-01-01

    This study evaluated the in vitro antibacterial activity of essential oils from Lippia graveolens (Mexican oregano), Origanum vulgaris (oregano), Thymus vulgaris (thyme), Rosmarinus officinalis (rosemary), Cymbopogon nardus (citronella), Cymbopogon citratus (lemongrass), and Eucalyptus citriodora (eucalyptus) against Escherichia coli (n = 22) strains isolated from Alouatta spp. feces. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL−1; MBC mean = 2618 μg mL−1), thyme (MIC mean = 2618 μg mL−1; MBC mean = 2909 μg mL−1), and oregano (MIC mean = 3418 μg mL−1; MBC mean = 4800 μg mL−1) showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL−1. Our results confirm the antimicrobial potential of some essential oils, which deserve further research. PMID:27313638

  6. Antimicrobial Susceptibility of Escherichia coli Strains Isolated from Alouatta spp. Feces to Essential Oils.

    PubMed

    Lara, Valéria Maria; Carregaro, Adriano Bonfim; Santurio, Deise Flores; de Sá, Mariangela Facco; Santurio, Janio Moraes; Alves, Sydney Hartz

    2016-01-01

    This study evaluated the in vitro antibacterial activity of essential oils from Lippia graveolens (Mexican oregano), Origanum vulgaris (oregano), Thymus vulgaris (thyme), Rosmarinus officinalis (rosemary), Cymbopogon nardus (citronella), Cymbopogon citratus (lemongrass), and Eucalyptus citriodora (eucalyptus) against Escherichia coli (n = 22) strains isolated from Alouatta spp. feces. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for each isolate using the broth microdilution technique. Essential oils of Mexican oregano (MIC mean = 1818 μg mL(-1); MBC mean = 2618 μg mL(-1)), thyme (MIC mean = 2618 μg mL(-1); MBC mean = 2909 μg mL(-1)), and oregano (MIC mean = 3418 μg mL(-1); MBC mean = 4800 μg mL(-1)) showed the best antibacterial activity, while essential oils of eucalyptus, rosemary, citronella, and lemongrass displayed no antibacterial activity at concentrations greater than or equal to 6400 μg mL(-1). Our results confirm the antimicrobial potential of some essential oils, which deserve further research.

  7. Conservation of plasmids among Escherichia coli K1 isolates of diverse origins.

    PubMed

    Mercer, A A; Morelli, G; Heuzenroeder, M; Kamke, M; Achtman, M

    1984-12-01

    Escherichia coli K1 isolates of various O types were previously assigned to different clonal groups. Members of the two clones defined by membrane pattern 9 (MP9) and serotypes O18:K1 and O1:K1 had been found to be very similar to each other. The plasmid contents of these bacteria confirmed this conclusion. Both groups carried a self-transmissible plasmid of the FI incompatibility group that coded for colicin production and a major outer membrane protein called the plasmid-coded protein (PCP). The size of this plasmid varied from 76 to 96 megadaltons, but restriction endonuclease digestion and DNA heteroduplex analysis revealed that these plasmids were highly related. O18:K1 bacteria of MP6 had previously been determined to represent a subclone, related to but different from O18:K1 MP9 bacteria. These MP6 bacteria carried a different, smaller IncFI plasmid which did not code for colicin production or the PCP protein. This smaller plasmid was primarily related to the larger plasmid within the regions of DNA encoding incompatibility, replication, and conjugation. O1:K1 bacteria of MP5 contained other unrelated plasmids in agreement with the previous conclusion that they are unrelated to O1:K1 bacteria of MP9. The bacteria examined had been isolated from two continents over a time span of 38 years, and the results attest to conservative inheritance of plasmids within bacteria of common descent.

  8. Virulence genes and antimicrobial susceptibilities of hemolytic and nonhemolytic Escherichia coli isolated from post-weaning piglets in central Thailand.

    PubMed

    Prapasarakul, Nuvee; Tummaruk, Padet; Niyomtum, Waree; Tripipat, Titima; Serichantalergs, Oralak

    2010-12-01

    The purpose of this study was to compare the existence of virulence genes in hemolytic Escherichia coli (HEC) and nonhemolytic E. coli (NHEC) isolated from weaner pigs in Thailand, and to determine their susceptibility to 10 antimicrobial agents. A total of 304 E. coli isolates were obtained from 90 piglets with diarrhea and 110 healthy piglets. Of these, 74 HEC isolates were obtained from 70 pigs with diarrhea, and 4 were obtained from 4 healthy pigs, while 190 and 40 NHEC were recovered from 110 healthy and 20 pigs with diarrhea, respectively. A ten digoxigenin (DIG)-labeled probe system was utilized for detecting genes encoding virulence-associated toxins and proteins in these isolates, and the minimal inhibitory concentration values against 10 antimicrobials were determined by means of the agar dilution technique. In total, 70.3% of the HEC isolates contained an exotoxin gene, lth, estp or stx2e, whereas 2.6% of the NHEC isolates hybridized with a gene probe for estp or stx2e. Over 90% of the isolates were resistant to most agents other than colistin and halquinol. The MIC(90) values of the HEC isolates for halquinol and colistin were 4 and 8 times greater than those of the NHEC isolates, respectively. The results represent the first characterization of resistant pathogenic E. coli distributed in the Thai pig industry. Amongst the HEC isolates, there appeared to be an association between the presence of some exotoxin genes, including lth, estp and stx2e, and reduced antimicrobial susceptibility.

  9. Isolation, phylogenetic group, drug resistance, biofilm formation, and adherence genes of Escherichia coli from poultry in central China.

    PubMed

    Wang, Yang; Yi, Li; Wang, Yuxin; Wang, Yuanguo; Cai, Ying; Zhao, Wenpeng; Ding, Chan

    2016-12-01

    The isolation and identification, genetic typing, antibiotic sensitivity, and biofilm formation of avian Escherichia coli in central China was studied. A total of 256 isolates of E. coli were obtained, and classified into groups: A (50.78%, 130/256), B1 (11.72%, 30/256), B2 (17.58%, 45/256), and D (19.92%, 51/256). Drug susceptibility testing revealed that the strains showed a high drug resistance rate against penicillin, aztreonam, rifampicin, kanamycin, clindamycin, and gentamicin, with 92.19% of strains exhibiting multi-drug resistance. A biofilm assay revealed that 81.64% of isolates could form biofilms. Of the total isolates, 25.39% of isolates showed strong biofilm-formation ability, 31.25% showed moderate biofilm-formation ability, 28.90% showed weak biofilm-formation ability, and 18.36% were unable to form biofilms. Most adhesion-associated genes were distributed among 5 or 8 genes in strong biofilm-forming ability isolates. However, adhesion-associated genes distributed among 1 or 4 genes were found in weak biofilm-forming ability isolates and non-ability isolates. The results showed a high drug resistance rate and biofilm formation ability in E.coli strains isolated from poultry. The isolates which have strong biofilm-forming ability were mostly belong to pathogenic E. coli (B2, D). Furthermore, it was the first report to demonstrate a positive correlation between adhesion-encoding genes and biofilms phenotype.

  10. 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 blaCTX-M-2 (22.22%), blaTEM (3.70%), blaPSE (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

  11. 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.

  12. Comparison of antimicrobial resistance in Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes strains isolated from organic and conventional poultry meat.

    PubMed

    Miranda, J M; Vázquez, B I; Fente, C A; Calo-Mata, P; Cepeda, A; Franco, C M

    2008-12-01

    The presence of Escherichia coli, Staphylococcus aureus, and Listeria monocytogenes was determined in 55 samples of organic poultry meat and in 61 samples of conventional poultry meat. A total of 220 E. coli, 192 S. aureus, and 71 L. monocytogenes strains were analyzed by an agar disk diffusion assay for their resistance to ampicillin, cephalothin, chloramphenicol, ciprofloxacin, doxycycline, fosfomycin, gentamicin, nitrofurantoin, streptomycin, and sulfisoxazole (E. coli); chloramphenicol, ciprofloxacin, clindamycin, doxycycline, erythromycin, gentamicin, nitrofurantoin, oxacillin, and sulfisoxazole (S. aureus); and chloramphenicol, doxycycline, erythromycin, gentamicin, sulfisoxazole, and vancomycin (L. monocytogenes). The results indicated a significantly higher (P < 0.0001) prevalence of E. coli but not of S. aureus and L. monocytogenes in organic poultry meat as compared with conventional poultry meat. E. coli isolated from organic poultry meat exhibited lower levels of antimicrobial resistance against 7 of the 10 antimicrobials tested as compared with isolates recovered from conventional meat. In the case of S. aureus and L. monocytogenes isolated from conventional poultry, antimicrobial resistance was significantly higher only for doxycycline as compared with strains isolated from organic poultry. In the case of E. coli, the presence of multiresistant strains was significantly higher (P < 0.0001) in conventional poultry meat as compared with organic poultry meat. Organically farmed poultry samples showed significantly lower development of antimicrobial resistance in intestinal bacteria such as E. coli.

  13. Characterization and virulence clustering analysis of extraintestinal pathogenic Escherichia coli isolated from swine in China.

    PubMed

    Zhu, Yinchu; Dong, Wenyang; Ma, Jiale; Yuan, Lvfeng; Hejair, Hassan M A; Pan, Zihao; Liu, Guangjin; Yao, Huochun

    2017-04-08

    Swine extraintestinal pathogenic Escherichia coli (ExPEC) is an important pathogen that leads to economic and welfare costs in the swine industry worldwide, and is occurring with increasing frequency in China. By far, various virulence factors have been recognized in ExPEC. Here, we investigated the virulence genotypes and clonal structure of collected strains to improve the knowledge of phylogenetic traits of porcine ExPECs in China. We isolated 64 Chinese porcine ExPEC strains from 2013 to 14 in China. By multiplex PCR, the distribution of isolates belonging to phylogenetic groups B1, B2, A and D was 9.4%, 10.9%, 57.8% and 21.9%, respectively. Nineteen virulence-related genes were detected by PCR assay; ompA, fimH, vat, traT and iutA were highly prevalent. Virulence-related genes were remarkably more prevalent in group B2 than in groups A, B1 and D; notably, usp, cnf1, hlyD, papA and ibeA were only found in group B2 strains. Genotyping analysis was performed and four clusters of strains (named I to IV) were identified. Cluster IV contained all isolates from group B2 and Cluster IV isolates had the strongest pathogenicity in a mouse infection model. As phylogenetic group B2 and D ExPEC isolates are generally considered virulent, multilocus sequence typing (MLST) analysis was performed for these isolates to further investigate genetic relationships. Two novel sequence types, ST5170 and ST5171, were discovered. Among the nine clonal complexes identified among our group B2 and D isolates, CC12 and CC95 have been indicated to have high zoonotic pathogenicity. The distinction between group B2 and non-B2 isolates in virulence and genotype accorded with MLST analysis. This study reveals significant genetic diversity among ExPEC isolates and helps us to better understand their pathogenesis. Importantly, our data suggest group B2 (Cluster IV) strains have the highest risk of causing animal disease and illustrate the correlation between genotype and virulence.

  14. Genotypic and phenotypic analysis of diarrheagenic Escherichia coli strains isolated from Brazilian children living in low socioeconomic level communities

    PubMed Central

    2013-01-01

    Background Childhood diarrheal diseases remain highly endemic in developing areas of Brazil. The importance of Escherichia coli among children with diarrhea in these areas was unknown. This study determined the prevalence of different E. coli categories in symptomatic and asymptomatic children from low socioeconomic level rural communities in southeastern Brazil. Methods A total of 560 stool samples were collected from 141 children with diarrhea (< 10 years) and 419 apparently healthy controls who resided in 23 communities. E. coli isolates (n = 1943) were subjected to two multiplex PCRs developed for the detection of enteropathogenic E. coli (EPEC), enteroaggregative E. coli (EAEC), diffusely adherent E. coli (DAEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), and Shiga toxin-producing E. coli (STEC). Strains were also examined for the presence of EPEC, EAEC, and DAEC by assays of adhesion to HEp-2 cells and by hybridization with specific DNA probes. Results Diarrheagenic E. coli strains were isolated from 253 (45.2%) children, and were associated with diarrhea in children aged < 5 years (p < 0.001). EAEC (20.9%), DAEC (11.6%), EPEC (9.3%) were the most frequent pathotypes, followed by ETEC (2.7%), EIEC (0.5%), and STEC (0.2%). Depending of the assay, EPEC, EAEC, and DAEC (collectively termed enteroadherent E. coli) strains were isolated in 45% to 56% of diarrhea cases, a significantly higher incidence than in controls (P < 0.05). Individually, only DAEC showed significant association with diarrhea (p < 0.05), particularly in children aged 2–5 years. Conclusion This study indicates that enteroadherent E. coli is an important cause of diarrhea in children living in low socioeconomic level communities in southeastern Brazil. Our results reveal that the PCR1 assay is an excellent tool for the identification of EAEC and DAEC. PMID:24010735

  15. Faecal Escherichia coli isolates from healthy dogs harbour CTX-M-15 and CMY-2 β-lactamases.

    PubMed

    Rocha-Gracia, R C; Cortés-Cortés, G; Lozano-Zarain, P; Bello, F; Martínez-Laguna, Y; Torres, C

    2015-03-01

    The presence of extended spectrum β-lactamase (ESBL) and plasmid-mediated AmpC β-lactamase (pAmpC) producing Escherichia coli, along with the mechanisms of antimicrobial resistance and the molecular types of isolates, was investigated in faecal samples from 53 healthy dogs in Mexico. Samples were inoculated on Levine agar plates with 2 µg/mL cefotaxime for recovery of cefotaxime-resistant (CTX(R)) E. coli. CTX(R)E. coli isolates were recovered from 9/53 (17%) samples; one isolate was characterised from each positive sample. ESBL producing E. coli isolates were detected in 3/53 (6%) samples; these isolates carried the blaCTX-M-15 gene and one isolate also carried blaSHV-2. These three ESBL-positive E. coli isolates belonged to phylogroup A and sequence types ST617, ST410 or ST3944. The remaining 6/53 (11%) samples contained pAmpC positive isolates; these isolates carried the blaCMY-2 gene, which encodes CMY-2 β-lactamase. These six isolates belonged to phylogroups A (n = 2), B1 (n = 1) and D (n = 3), and sequences types ST1431, ST57, ST93 and ST4565. One CMY-2 β-lactamase positive E. coli isolate of lineage ST93 had the -32 mutation in the chromosomal ampC promoter/attenuator region. Five ESBL/pAmpC positive E. coli isolates carried class 1 integrons (dfrA17-aadA5, aadA and aadA/aadB arrays were detected in three isolates) and one isolate carried a class 2 integron (dfrA12-sat2-aadA1). The aac(6')Ib-cr, aac(3)-II, qnrB19, tet(A), tet(B), cmlA, and sul3 genes were also detected. All studied isolates showed unrelated PFGE-patterns. To our knowledge, this is the first description of ESBL-producing E. coli and the second of pAmpC-producing E. coli from healthy dogs in America. Our results suggest the potential zoonotic role of dogs in the transmission to humans of ESBL and pAmpC E. coli in the household environment.

  16. Multidrug-Resistant Escherichia coli Strains Isolated from Patients Are Associated with Class 1 and 2 Integrons.

    PubMed

    Lavakhamseh, Hamid; Mohajeri, Parviz; Rouhi, Samaneh; Shakib, Pegah; Ramazanzadeh, Rashid; Rasani, Afshin; Mansouri, Majid

    2016-01-01

    Escherichia coli isolates displaying multidrug-resistance (MDR) are a major health care problem that results in mortality and morbidity. Integrons are DNA elements in E.coli that are related to antibiotic resistance. The aim of this study was to determine class 1 and 2 integrons and MDR in E. coli isolates obtained from patients in two Sanandaj hospitals, located in Iran. 120 isolates of E. coli were obtained from clinical specimens (from November 2013 to April 2014), and the susceptibility of E. coli antimicrobial agents was determined using the Kirby-Bauer disk diffusion method according to the CLSI. PCR were applied for detection of class 1 and 2 integrons in E. coli isolates. SPSS software v16 and the x03C7;2 test were used for statistical analysis in order to calculate the association between antibiotic resistance and the presence of integrons (p < 0.05). In a total of 120 E. coli isolates, 42.5% had MDR. Integrons were found in 50.9% of the MDR isolates, and included 47.05% class 1 and 3.92% class 2 integrons. The strains did not have both classes of integrons simultaneously. An association between resistance to antibiotics and integrons was found. Our results showed that int1 and int2 genes present in E. coli isolates obtained from patients cause MDR in this isolates. Since such bacteria are a reservoir for the transmission of MDR bacteria, appropriate programs are necessary to reduce this problem. © 2015 S. Karger AG, Basel.

  17. Multidrug Resistance in Escherichia coli Strains Isolated from Infections in Dogs and Cats in Poland (2007–2013)

    PubMed Central

    Rzewuska, Magdalena; Czopowicz, Michał; Kizerwetter-Świda, Magdalena; Chrobak, Dorota; Błaszczak, Borys; Binek, Marian

    2015-01-01

    The antimicrobial susceptibility of Escherichia coli isolates associated with various types of infections in dogs and cats was determined. The studied isolates were most frequently susceptible to fluoroquinolones and the extended-spectrum cephalosporins (ESCs), antimicrobials commonly used in treatment of infections in companion animals. However, an increase in the percentage of strains resistant to β-lactam antibiotics including ESCs was noted between January 2007 and December 2013. The frequency of multidrug-resistant (MDR) E. coli isolation (66.8% of isolates) is alarming. Moreover, the statistically significant increase of the percentage of MDR isolates was observed during the study period. No difference in the prevalence of multidrug resistance was found between bacteria causing intestinal and extraintestinal infections and between canine and feline isolates. Nonhemolytic E. coli isolates were MDR more often than hemolytic ones. Our study showed the companion animals in Poland as an important reservoir of MDR bacteria. These results indicate that continuous monitoring of canine and feline E. coli antimicrobial susceptibility is required. Furthermore, introduction and application of recommendations for appropriate use of antimicrobials in small animal practice should be essential to minimize the emergence of multidrug resistance among E. coli in companion animals. PMID:25667937

  18. Multidrug resistance in Escherichia coli strains isolated from infections in dogs and cats in Poland (2007-2013).

    PubMed

    Rzewuska, Magdalena; Czopowicz, Michał; Kizerwetter-Świda, Magdalena; Chrobak, Dorota; Błaszczak, Borys; Binek, Marian

    2015-01-01

    The antimicrobial susceptibility of Escherichia coli isolates associated with various types of infections in dogs and cats was determined. The studied isolates were most frequently susceptible to fluoroquinolones and the extended-spectrum cephalosporins (ESCs), antimicrobials commonly used in treatment of infections in companion animals. However, an increase in the percentage of strains resistant to β-lactam antibiotics including ESCs was noted between January 2007 and December 2013. The frequency of multidrug-resistant (MDR) E. coli isolation (66.8% of isolates) is alarming. Moreover, the statistically significant increase of the percentage of MDR isolates was observed during the study period. No difference in the prevalence of multidrug resistance was found between bacteria causing intestinal and extraintestinal infections and between canine and feline isolates. Nonhemolytic E. coli isolates were MDR more often than hemolytic ones. Our study showed the companion animals in Poland as an important reservoir of MDR bacteria. These results indicate that continuous monitoring of canine and feline E. coli antimicrobial susceptibility is required. Furthermore, introduction and application of recommendations for appropriate use of antimicrobials in small animal practice should be essential to minimize the emergence of multidrug resistance among E. coli in companion animals.

  19. Isolation, genotyping and antimicrobial resistance of Shiga toxin-producing Escherichia coli.

    PubMed

    Amézquita-López, Bianca A; Soto-Beltrán, Marcela; Lee, Bertram G; Yambao, Jaszemyn C; Quiñones, Beatriz

    2017-07-18

    Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen linked to outbreaks of human gastroenteritis with diverse clinical spectra. In this review, we have examined the currently methodologies and molecular characterization techniques for assessing the phenotypic, genotypic and functional characteristics of STEC O157 and non-O157. In particular, traditional culture and isolation methods, including selective enrichment and differential plating, have enabled the effective recovery of STEC. Following recovery, immunological serotyping of somatic surface antigens (O-antigens) and flagellum (H-antigens) are employed for the classification of the STEC isolates. Molecular genotyping methods, including multiple-locus variable-number tandem repeat analysis, arrays, and whole genome sequencing, can discriminate the isolate virulence profile beyond the serotype level. Virulence profiling is focused on the identification of chromosomal and plasmid genes coding for adhesins, cytotoxins, effectors, and hemolysins to better assess the pathogenic potential of the recovered STEC isolates. Important animal reservoirs are cattle and other small domestic ruminants. STEC can also be recovered from other carriers, such as mammals, birds, fish, amphibians, shellfish and insects. Finally, antimicrobial resistance in STEC is a matter of growing concern, supporting the need to monitor the use of these agents by private, public and agricultural sectors. Certain antimicrobials can induce Shiga toxin production and thus promote the onset of severe disease symptoms in humans. Together, this information will provide a better understanding of risks associated with STEC and will aid in the development of efficient and targeted intervention strategies. Copyright © 2017. Published by Elsevier B.V.

  20. Effect of plasmids harbouring blaCTX-M on the virulence and fitness of Escherichia coli ST131 isolates.

    PubMed

    Shin, Juyoun; Ko, Kwan Soo

    2015-08-01

    The effect of plasmids harbouring blaCTX-M on the virulence and fitness on Escherichia coli sequence type 131 (ST131) isolates was investigated. Plasmids harbouring blaCTX-M-14 or blaCTX-M-15 were transferred by transconjugation into five non-extended-spectrum β-lactamase (ESBL)-producing ST131 isolates. Clinical non-ESBL-producing ST131 isolates demonstrated a higher degree of biofilm formation and serum resistance compared with CTX-M-producing ST131 isolates. In addition, non-ESBL-producing isolates were more competitive than CTX-M-producing isolates. Transconjugants showed no significant defect in growth rate and competitiveness compared with their hosts. However, serum resistance and biofilm formation were diminished in the transconjugants. In conclusion, non-ESBL-producing E. coli ST131 isolates were more competitive and virulent than CTX-M-producing E. coli ST131 isolates. However, transconjugants harbouring blaCTX-M were no less competitive than their susceptible hosts, which may partially explain the global dissemination of CTX-M-14- and CTX-M-15-producing E. coli ST131 isolates, in addition to their increased antimicrobial resistance. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  1. Potential enterovirulence and antimicrobial resistance in Escherichia coli isolates from aquatic environments in Rio de Janeiro, Brazil.

    PubMed

    Rebello, Raquel Costa de Luca; Regua-Mangia, Adriana Hamond

    2014-08-15

    Escherichia coli contamination in aquatic ecosystems has emerged as a relevant concern of public health impact, especially in developing areas. In this study, E. coli isolates were recovered from residential, industrial, agricultural, hospital wastewaters and recreational waters and, further characterized according to diarrheagenic potential, phylotyping and antimicrobial resistance phenotype. Among the total 178 E. coli isolates, antimicrobial resistance was detected in 37% to at least one of the 11 antimicrobials tested. The highest percentage of resistant E. coli was recovered from agricultural wastewaters (57.7%) followed by recreational waters (56.4%), hospital (34.5%), residential (22.7%) and industrial wastewaters (22.2%). Twenty-three resistance profiles (I-XXIII) were detected and 17 isolates exhibited the MDR phenotype. 11.2% of the total E. coli isolates carried diarrheagenic markers: astA (7.3%, 13/178), stx1 (2.8%, 05/178), escV (2.2%, 04/178) and estIa (0.6%, 01/178). All isolates harbored the uidA gene. E. coli isolates were mostly found in phylogenetic groups A (91.6%, 163/178) followed by groups D (5%, 09/178) and B2 (3.4%, 06/178). Specific gene combinations characterized E. coli pathotypes as ETEC (01/20), ATEC (04/20) and STEC (05/20) which belonged to A (75%, 15/20), D (15%, 03/20) and B2 (10%, 02/20) phylogroups. Our results revealed the widespread distribution of E. coli in aquatic systems in Rio de Janeiro. The circulation of pathogenic E. coli and antimicrobial resistance within bacterial population represents high risk to ecosystem and human health and highlights epidemiological surveillance and sanitary improvement.

  2. Potential pathogens, antimicrobial patterns and genotypic diversity of Escherichia coli isolates in constructed wetlands treating swine wastewater.

    PubMed

    Ibekwe, A M; Murinda, Shelton E; DebRoy, Chitrita; Reddy, Gudigopura B

    2016-02-01

    Escherichia coli populations originating from swine houses through constructed wetlands were analyzed for potential pathogens, antimicrobial susceptibility patterns, and genotypic diversity. Escherichia coli isolates (n = 493) were screened for the presence of the following virulence genes: stx1, stx2 and eae (Shiga toxin-producing E. coli [STEC]), heat-labile enterotoxin (LT) genes and heat stable toxin STa and STb (enterotoxigenic E. coli (ETEC), cytotoxin necrotizing factors 1 and 2 (cnf1 and cnf2 [necrotoxigenic E. coli- NTEC]), as well as O and H antigens, and the presence of the antibiotic resistance genes blaTEM, blaSHV, blaCMY-2, tet A, tet B, tet C, mph(A), aadA, StrA/B, sul1, sul2 and sul3. The commensal strains were further screened for 16 antimicrobials and characterized by BOX AIR-1 PCR for unique genotypes. The highest antibiotic resistance prevalence was for tetracycline, followed by erythromycin, ampicillin, streptomycin, sulfisoxazole and kanamycin. Our data showed that most of the isolates had high distribution of single or multidrug-resistant (MDR) genotypes. Therefore, the occurrence of MDR E. coli in the wetland is a matter of great concern due to possible transfer of resistance genes from nonpathogenic to pathogenic strains or vice versa in the environment.

  3. OCCURRENCE OF VIRULENCE FACTOR ACTIVITY RELATIONSHIP (VFAR) IN ESCHERICHIA COLI ISOLATED FROM MUNICIPAL WASTEWATER EFFLUENTS

    EPA Science Inventory

    Escherichia coli O157:H7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype, including slow sorbitol fermentati...

  4. OCCURRENCE OF VIRTUENCE FACTOR ACTIVITY RELATIONSHIP (VFAR) IN ESCHERICHIA COLI ISOLATED FROM MUNICIPAL WASTEWATER

    EPA Science Inventory

    Escherichia coli O157 H:7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype. These phenotypic characteristics...

  5. OCCURRENCE OF VIRTUENCE FACTOR ACTIVITY RELATIONSHIP (VFAR) IN ESCHERICHIA COLI ISOLATED FROM MUNICIPAL WASTEWATER

    EPA Science Inventory

    Escherichia coli O157 H:7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype. These phenotypic characteristics...

  6. Comparative genomics of two super-shedder isolates of Escherichia coli O157:H7

    USDA-ARS?s Scientific Manuscript database

    Shiga toxin-producing Escherichia coli O157:H7 (O157) are zoonotic foodborne pathogens and of major public health concern that cause considerable intestinal and extra-intestinal illnesses in humans. O157 colonize the recto-anal junction (RAJ) of asymptomatic cattle who shed the bacterium into the en...

  7. OCCURRENCE OF VIRULENCE FACTOR ACTIVITY RELATIONSHIP (VFAR) IN ESCHERICHIA COLI ISOLATED FROM MUNICIPAL WASTEWATER EFFLUENTS

    EPA Science Inventory

    Escherichia coli O157:H7 has been linked to waterborne outbreaks in the United States and abroad. Methods employed to detect this pathogen typically are cultural based and take advantage of phenotypic traits that are specific for this serotype, including slow sorbitol fermentati...

  8. Antimicrobial resistance in Campylobacter, Salmonella, and Escherichia coli isolated from retail grain-fed veal meat from Southern Ontario, Canada.

    PubMed

    Cook, Angela; Reid-Smith, Richard J; Irwin, Rebecca J; McEwen, Scott A; Young, Virginia; Ribble, Carl

    2011-08-01

    This study estimated the prevalence of Salmonella, Campylobacter, and Escherichia coli isolates in fresh retail grain-fed veal obtained in Ontario, Canada. The prevalence and antimicrobial resistance patterns were examined for points of public health significance. Veal samples (n = 528) were collected from February 2003 through May 2004. Twenty-one Salmonella isolates were recovered from 18 (4%) of 438 samples and underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was found in 6 (29%) of 21 Salmonella isolates; 5 (24%) of 21 isolates were resistant to five or more antimicrobials. No resistance to antimicrobials of very high human health importance was observed. Ampicillin-chloramphenicolstreptomycin-sulfamethoxazole-tetracycline resistance was found in 5 (3%) of 21 Salmonella isolates. Campylobacter isolates were recovered from 5 (1%) of 438 samples; 6 isolates underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was documented in 3 (50%) of 6 Campylobacter isolates. No Campylobacter isolates were resistant to five or more antimicrobials or category I antimicrobials. E. coli isolates were recovered from 387 (88%) of 438 samples; 1,258 isolates underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was found in 678 (54%) of 1,258 E. coli isolates; 128 (10%) of 1,258 were resistant to five or more antimicrobials. Five (0.4%) and 7 (0.6%) of 1,258 E. coli isolates were resistant to ceftiofur and ceftriaxone, respectively, while 34 (3%) of 1,258 were resistant to nalidixic acid. Ciprofloxacin resistance was not detected. There were 101 different resistance patterns observed among E. coli isolates; resistance to tetracycline alone (12.7%, 161 of 1,258) was most frequently observed. This study provides baseline prevalence and antimicrobial resistance data and highlights potential public health concerns.

  9. Proteomic comparison of three clinical diarrhoeagenic drug-resistant Escherichia coli isolates grown on CHROMagar™STEC media.

    PubMed

    Kalule, John Bosco; Fortuin, Suereta; Calder, Bridget; Robberts, Lourens; Keddy, Karen H; Nel, Andrew J M; Garnett, Shaun; Nicol, Mark; Warner, Digby F; Soares, Nelson C; Blackburn, Jonathan M

    2017-09-05

    Shiga-toxin-producing Escherichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) are key diarrhoea-causing foodborne pathogens. We used proteomics to characterize the virulence and antimicrobial resistance protein profiles of three clinical pathogenic E. coli isolates (two EPEC [one resistant to ciprofloxacin] and one STEC) cultured on CHROMagar™STEC solid media after minimal laboratory passage. We identified 4767 unique peptides from 1630 protein group across all three clinical E. coli strains. Label-free proteomic analysis allowed the identification of virulence and drug resistance proteins that were unique to each of the clinical isolates compared in this study. The B subunit of Shiga toxin, ToxB, was uniquely detected in the STEC strain while several other virulence factors including SheA, OmpF, OmpC and OmpX were significantly more abundant in the STEC strain. The ciprofloxacin resistant EPEC isolate possessed reduced levels of key virulence proteins compared to the ciprofloxacin susceptible EPEC and STEC strains. Parallel reaction monitoring assays validated the presence of biologically relevant proteins across biologically-replicated cultures. Propagation of clinical isolates on a relevant solid medium followed by mass spectrometry analysis represents a convenient means to quantify virulence factors and drug resistance determinants that might otherwise be lost through extensive in vitro passage in enteropathogenic bacteria. Through the use of quantitative proteomics, we have characterized the virulence and antimicrobial resistance attributes of three clinically isolated, pathogenic E. coli strains cultured on solid media. Our results provide new, quantitative data on the expressed proteomes of these tellurite-resistant, diarrhoeagenic E. coli strains and reveal a subset of antimicrobial resistance and virulence proteins that are differentially abundant between these clinical strains. Our quantitative proteomics-based approach should thus have

  10. Isolation and molecular characterization of multidrug-resistant strains of Escherichia coli and Salmonella from retail chicken meat in Japan.

    PubMed

    Ahmed, Ashraf M; Shimabukuro, Hirofumi; Shimamoto, Tadashi

    2009-09-01

    Sixty-nine Escherichia coli and 10 Salmonella isolates, recovered from retail chicken meat in Hiroshima prefecture, Japan, were assayed for antimicrobial susceptibility, the presence of integrons and antimicrobial resistance genes. Twenty-eight out of 69 (40.6%) of E. coli and all 10 Salmonella isolates were exhibited multidrug resistance phenotypes. The most commonly reported resistance phenotypes were against ampicillin, streptomycin, spectinomycin, kanamycin, tetracycline, and trimethoprim/sulfamethoxazole. PCR screening for integrons showed that 8 (11.6%) of the E. coli isolates were positive for the class 1 integrons and 1 isolate (1.4%) was positive for the class 2 integrons. Among the 10 Salmonella isolates, 9 were positive for class 1 integrons and none was positive for class 2 integrons. The identified antibiotic resistance gene cassettes within the class 1 integrons were dfrA1, dfrA7, aadA1, aadB, and catB3, while dfrA1, sat2, and aadA1 were identified within class 2 integron. The beta-lactamase resistance gene bla(TEM-1) was identified in 12 (17.3%) of E. coli isolates and in only one of the Salmonella isolates. The bla(CMY-2) gene, encoding AmpC beta-lactamase, was detected in 16 (23.2%) of the E. coli isolates only. Conjugation experiments demonstrated that there was plasmid-mediated transfer of bla(CMY-2) and bla(TEM-1). These results highlighted the role of retail chicken meat as a potential source for multidrug-resistant strains of E. coli and Salmonella. To the best of our knowledge, this is the 1st report of isolation and molecular characterization of multidrug-resistant strains of E. coli from retail chicken meat in Japan.

  11. 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.

  12. Human Escherichia coli isolates from hemocultures: Septicemia linked to urogenital tract infections is caused by isolates harboring more virulence genes than bacteraemia linked to other conditions.

    PubMed

    Micenková, Lenka; Beňová, Alžbeta; Frankovičová, Lucia; Bosák, Juraj; Vrba, Martin; Ševčíková, Alena; Kmeťová, Marta; Šmajs, David

    2017-02-27

    Escherichia coli is the most common cause of bloodstream infections and community-acquired sepsis. The main aim of this study was to determine virulence characteristics of E. coli isolates from hemocultures of patients with a primary disease of urogenital tract, digestive system, a neoplastic blood disease, or other conditions. Results from a set of 314 E. coli isolates from hemocultures were compared to data from a previously published analysis of 1283 fecal commensal E. coli isolates. Genetic profiling of the 314 E. coli isolates involved determination of phylogenetic group (A, B1, B2, D, C, E, and F), identification of 21 virulence factors, as well as 30 bacteriocin-encoding determinants. Pulsed-field gel electrophoresis was used to analyze clonal character of the hemoculture-derived isolates. The E. coli isolates from hemocultures belonged mainly to phylogenetic groups B2 (59.9%) and D (21.0%), and less frequently to phylogroups A (10.2%) and B1 (5.7%). Commonly detected virulence factors included adhesins (fimA 92.0%, pap 47.1%, and sfa 26.8%), and iron-uptake encoding genes (fyuA 87.9%, fepC 79.6%, aer 70.7%, iucC 68.2%, and ireA 13.7%), followed by colibactin (pks island 31.5%), and cytotoxic necrotizing factor (cnf1 11.1%). A higher frequency of microcin producers (and microcin M determinant) and a lower frequency of colicin Ib and microcin B17 was found in hemoculture-derived isolates compared to commensal fecal isolates. E. coli isolates from hemocultures harbored more virulence genes compared to fecal E. coli isolates. In addition, hemoculture E. coli isolates from patients with primary diagnosis related to urogenital tract were clearly different and more virulence genes were detected in these isolates compared to both fecal isolates and hemoculture-derived isolates from patients with blood and gastrointestinal diseases.

  13. Antimicrobial Resistance and Molecular Characterization of Extended-Spectrum β-Lactamases and Other Escherichia coli Isolated from Food of Animal Origin and Human Intestinal Isolates.

    PubMed

    Krizman, Manja; Avgustin, Jerneja Ambrozic; Zdovc, Irena; Golob, Majda; Trkov, Marija; Ciglenecki, Urska Jamnikar; Biasizzo, Majda; Kirbis, Andrej

    2017-01-01

    Antibiotics have always appeared miraculous, saving innumerable lives. However, the unwise use of antimicrobial drugs has led to the appearance of resistant bacteria. The purpose of this study was to evaluate antimicrobial resistance in Escherichia coli (n =160) isolated from food of animal origin. The focus was on E. coli -producing extended-spectrum β-lactamases. E. coli was chosen because it is a part of the normal microbiota in mammals and can enter the food chain during slaughtering and food manipulation. Subsequently, its resistance genes can be transferred to pathogenic bacteria and human microbiota. Phenotypic and genotypic analyses of selected antimicrobial resistances were carried out together with a molecular analysis of virulence genes. E. coli isolates from food of animal origin were compared with clinical E. coli strains isolated from the human intestinal tract. Extended-spectrum β-lactamase-producing E. coli isolates were found in 9.4% of food isolates and in 1.8% of intestinal isolates. Phylogenetically, the majority of food (86.3%) and intestinal E. coli (58.1%) isolates were found to belong to the commensal phylogenetic groups A and B1. The distribution of 4 of 14 analyzed virulence factors was similar in the food and intestinal isolates. Strains isolated from food in Slovenia harbored resistance genes and virulence factors, which can constitute a problem for food safety if not handled properly.

  14. Phenotypic antibiotic resistance of Escherichia coli and E. coli O157 isolated from water, sediment and biofilms in an agricultural watershed in British Columbia.

    PubMed

    Maal-Bared, Rasha; Bartlett, Karen H; Bowie, William R; Hall, Eric R

    2013-01-15

    This study examined the distribution of antibiotic resistant Escherichia coli and E. coli O157 isolated from water, sediment and biofilms in an intensive agricultural watershed (Elk Creek, British Columbia) between 2005 and 2007. It also examined physical and chemical water parameters associated with antibiotic resistance. Broth microdilution techniques were used to determine minimum inhibitory concentrations (MIC) for E. coli (n=214) and E. coli O157 (n=27) recovered isolates for ampicillin, cefotaxime, ciprofloxacin, nalidixic acid, streptomycin and tetracycline. Both E. coli and E. coli O157 isolates showed highest frequency of resistance to tetracycline, ampicillin, streptomycin and nalidixic acid; respectively. For E. coli, the highest frequency of resistance was observed at the most agriculturally-impacted site, while the lowest frequency of resistance was found at the headwaters. Sediment and river rock biofilms were the most likely to be associated with resistant E. coli, while water was the least likely. While seasonality (wet versus dry) had no relationship with resistance frequency, length of biofilm colonization of the substratum in the aquatic environment only affected resistance frequency to nalidixic acid and tetracycline. Multivariate logistic regressions showed that water depth, nutrient concentrations, temperature, dissolved oxygen and salinity had statistically significant associations with frequency of E. coli resistance to nalidixic acid, streptomycin, ampicillin and tetracycline. The results indicate that antibiotic resistant E. coli and E. coli O157 were prevalent in an agricultural stream. Since E. coli is adept at horizontal gene transfer and prevalent in biofilms and sediment, where ample opportunities for genetic exchange with potential environmental pathogens present themselves, resistant isolates may present a risk to ecosystem, wildlife and public health.

  15. Escherichia coli biofilms

    PubMed Central

    Beloin, Christophe; Roux, Agnès; Ghigo, Jean-Marc

    2008-01-01

    Escherichia coli is a predominant species among facultative anaerobic bacteria of the gastrointestinal tract. Both its frequent community lifestyle and the availability of a wide array of genetic tools contributed to establish E. coli as a relevant model organism for the study of surface colonization. Several key factors, including different extracellular appendages, are implicated in E. coli surface colonization and their expression and activity are finely regulated, both in space and time, to ensure productive events leading to mature biofilm formation. This chapter will present known molecular mechanisms underlying biofilm development in both commensal and pathogenic E. coli. PMID:18453280

  16. 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.

  17. Detection of pap-, sfa- and afa-specific DNA sequences in Escherichia coli strains isolated from extraintestinal material.

    PubMed

    Bogyiová, E; Kmetová, M; Biros, E; Siegfried, L

    2002-01-01

    P-fimbriae, S-fimbriae and AFA-adhesins are virulence factors responsible for adherence of Escherichia coli strains to extraintestinal host-cell surface. Detection of pap-, sfa- and afa-specific sequences performed by PCR revealed 74% pap+, 65% sfa+, and 8.3% afa+ strains in a group of 84 extraintestinal E. coli isolates. Detection in a group of fecal strains showed 29% pap+, 21% sfa+ and 4% afa+ strains. pap together with sfa were found as the most frequent combination (56%) among extraintestinal isolates probably due to localization of pap- and sfa-operons on a common pathogenicity island. The occurrence of afa-specific sequence among 56 urine strains was 11%, although no afa+ strain was detected among 28 gynecological isolates. No strains with detected adhesin operons were found among twenty (24%) extraintestinal E. coli strains.

  18. [The comparison of antibiotic susceptibilities of uropathogenic Escherichia coli isolates in transition from CLSI to EUCAST].

    PubMed

    Süzük, Serap; Kaşkatepe, Banu; Avcıküçük, Havva; Aksaray, Sebahat; Başustaoğlu, Ahmet

    2015-10-01

    Determination of treatment protocols for infections according to antimicrobial susceptibility test (AST) results is are important for controlling the problem of antibiotic resistance. Two standards are widely used in the world. One of them is Clinical Laboratory Standards Institute (CLSI) standards used in Turkey for many years and the other is the European Committee on Antimicrobial Susceptibility Testing (EUCAST) standards which is used in European Union member countries and came into use in 2015 in Turkey. Since the EUCAST standards had higher clinical sensitivity limits particularly for gram-negative bacilli compared to CLSI (2009) standards, there will be some changes in antibiotic resistance profiles of Turkey with the use of EUCAST. CLSI has changed zone diameters after 2009 versions and the differences between the two standards were brought to a minimum level. Knowledge of local epidemiological data is important to determine empirical therapy which will be used in urinary tract infections (UTI). The aim of this study was to determine the differences of antibiotic susceptibility zone diameters based on our local epidemiological data among uropathogenic Escherichia coli isolates according to EUCAST 2014 and CLSI 2014 standards. A total of 298 E.coli strains isolated from urine samples as the cause of uncomplicated acute UTI agents, were included in the study. Isolates were identified by conventional methods and with BBL Crystal E/NF ID System (Becton Dickinson, USA). AST was performed with Kirby Bauer disk diffusion method and results were evaluated and interpreted according to the CLSI 2014 and EUCAST 2014 standards. According to the results, susceptibility rates of isolates against amikacin (100%) and trimethoprim-sulfamethoxazole (63.09%) were identical in both standards. However, statistically significant differences were observed between CLSI and EUCAST standards in terms of susceptibilities against gentamicin (91.95% and 84.56%, respectively; p= 0

  19. Molecular characterization of integrons in clinical isolates of betalactamase-producing Escherichia coli and Klebsiella pneumoniae in Iran.

    PubMed

    Zeighami, Habib; Haghi, Fakhri; Hajiahmadi, Fahimeh

    2015-06-01

    Integrons are considered to play a significant role in the evolution and spread of antibiotic resistance genes. A total of 349 clinical isolates of Escherichia coli and Klebsiella pneumoniae were investigated for molecular characterization of integrons and betalactamases. Antimicrobial susceptibility testing was also performed as the Clinical and Laboratory Standards Institute (CLSI) guidelines. The frequency of extended spectrum betalactamases (ESBL) or metallo-betalactamases (MBL)-producing isolates, patient demographics, and the susceptibility to various antimicrobial agents were described. BlaCTX-M was the most frequently detected betalactamase in all isolates. Moreover, MBL producing K. pneumoniae carried blaIMP and blaVIM at 100 and 41·6%, respectively but no MBL-positive E. coli was detected. Class 1 integrons were more frequent among E. coli and K. pneumoniae isolates in comparison with class 2 integrons and the frequency of intI2 in K. pneumoniae was significantly higher than E. coli isolates. Five different resistance gene arrays were identified among class 1 integrons. Dihydrofolate reductase (dfrA) and aminoglycoside adenyltransferase (aad) gene cassettes were found to be predominant in the class 1 integrons. These results indicate that class 1 integrons are widespread among ESBL-producing isolates of K. pneumoniae and E. coli and appropriate surveillance and control measures are essential to prevent further dissemination of these elements among Enterobacteriaceae in our country.

  20. Characterization of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Pigs and Farm Workers.

    PubMed

    Zhang, Hongna; Zhai, Zhenzhen; Li, Qing; Liu, Linghong; Guo, Shuyuan; Li, Qimeng; Yang, Lingling; Ye, Chaoqun; Chang, Weishan; Zhai, Jing

    2016-09-01

    Food-producing animals can serve as reservoirs for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli . The present study aimed to characterize and compare ESBL-carrying E. coli isolates from both pigs and farm workers. Rectal swabs were obtained from 60 pigs on four pig-fattening farms (15 samples per farm), and rectal swabs were taken from 40 farm workers on these farms (10 samples per farm). ESBL-carrying E. coli isolates from the workers and pigs were characterized by ESBL genotype, antibiotic susceptibility, enterobacterial repetitive intergenic consensus type, and multilocus sequence type. ESBL-producing E. coli was detected in 34 (56.7%) of 60 pigs, and 20.0% (8 of 40) of the farm workers were positive for ESBL-producing E. coli . More importantly, ESBL-producing E. coli isolates with the same β-lactamase genes, antibiotic resistance profiles, enterobacterial repetitive intergenic consensus types, and multilocus sequence types were detected in both pigs and workers on the same pig farm. These findings were suggestive for transfer of ESBL-producing E. coli between animals and humans.

  1. 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.

  2. Bactericidal activity of Cu-, Zn-, and Ag-containing zeolites toward Escherichia coli isolates.

    PubMed

    Milenkovic, Jelena; Hrenovic, Jasna; Matijasevic, Danka; Niksic, Miomir; Rajic, Nevenka

    2017-07-13

    Two types of zeolites-natural clinoptilolite (NZ) and synthetic zeolite A (A)-were enriched with approx. 0.25 mmol of Cu(II), Zn(II), or Ag(I) ions, and the obtained materials (M-Z) were tested against three different isolates of Escherichia coli. Two isolates were environmental isolates from waters in Serbia whereas the third one was DSM 498. Antibacterial activity was studied in different water media-nutrient-rich media (peptone water), water from Sava Lake, and commercially available spring water. The Ag-containing zeolites showed bactericidal activity in the nutrient-rich peptone water after 1 h of contact. Cu- and Zn-containing zeolites showed bactericidal activity in real water samples. Antibacterial activity of the M-Z decreases in all three examined water media in the following order: Ag-NZ ≈ Ag-A > Cu-NZ ≈ Cu-A > Zn-NZ > Zn-A, suggesting that mainly the metal type and not the zeolite type have a role in the antibacterial activity. Leaching experiments showed small amounts of the leached Cu(II) and Zn(II) ions, indicating that the antibacterial activity is not due to the metal ions but should be attributed to the M-Z itself. However, leached amounts of Ag(I) from Ag-NZ and Ag-A in peptone water indicate that the released Ag(I) could be mainly responsible for the bactericidal effect of the Ag(I)-containing zeolites. Since no loss of cellular material was found, the antibacterial activity is not attributed to cytoplasmic membrane damage.

  3. Molecular mechanisms of antibiotic resistance in diarrhoeagenic Escherichia coli isolated from children.

    PubMed

    Mosquito, Susan; Ruiz, Joaquim; Pons, María J; Durand, David; Barletta, Francesca; Ochoa, Theresa J

    2012-12-01

    Diarrhoeagenic Escherichia coli (DEC) are an important cause of diarrhoea in children and are associated with high antibiotic resistance. However, there are few studies on the molecular mechanisms of resistance in this group of bacteria. The aim of this study was to determine the mechanisms associated with antibiotic resistance in the most common phenotypes of DEC. A total of 369 E. coli strains [commensal strains and DEC from children with ('DEC-diarrhoea') or without ('DEC-control') diarrhoea] isolated from children aged <1 year in periurban districts of Lima, Peru, were analysed. In total, 154 ampicillin-resistant strains (36 commensals, 33 DEC-control and 85 DEC-diarrhoea) were studied by PCR for the most prevalent resistance mechanisms to ampicillin, trimethoprim/sulfamethoxazole (SXT), tetracycline and chloramphenicol as well as for integrase types 1 and 2. In addition, restriction fragment length polymorphism was performed for SXT-resistant strains. Commensal strains were more frequently resistant to nalidixic acid and ciprofloxacin (68% and 28%, respectively) than DEC strains (23% and 2%, respectively) (P<0.05). DEC-diarrhoea strains were more frequently SXT-resistant (78%) compared with DEC-control strains (65%) and commensal strains (60%) (P<0.05). The most frequent mechanisms of antibiotic resistance in DEC strains were: for β-lactams, bla(TEM) (31%; 37/118); for SXT, sul2 (48%; 49/103); for tetracycline, tetA (27%; 23/84); and for chloramphenicol, cat (80%; 28/35). The genes sul1 and dfrA1, related to SXT resistance, were more frequent in the DEC-diarrhoea group (41% and 28%, respectively) than in the other two groups (P<0.05). There was a high diversity of resistance genes in DEC, including symptomatic strains.

  4. Phylogenetic relationships of Shiga toxin-producing Escherichia coli isolated from Peruvian children

    PubMed Central

    Contreras, C. A.; Ruiz, J.; Lacher, D. W.; Rivera, F. P.; Saenz, Y.; Chea-Woo, E.; Zavaleta, N.; Gil, A. I.; Lanata, C. F.; Huicho, L.; Maves, R. C.; Torres, C.; DebRoy, C.; Cleary, T. G.

    2011-01-01

    The aim of this study was to determine the prevalence, virulence factors (stx, eae, ehxA and astA) and phylogenetic relationships [PFGE and multilocus sequence typing (MLST)] of Shiga toxin-producing Escherichia coli (STEC) strains isolated from four previous cohort studies in 2212 Peruvian children aged <36 months. STEC prevalence was 0.4 % (14/3219) in diarrhoeal and 0.6 % (15/2695) in control samples. None of the infected children developed haemolytic uraemic syndrome (HUS) or other complications of STEC. stx1 was present in 83 % of strains, stx2 in 17 %, eae in 72 %, ehxA in 59 % and astA in 14 %. The most common serotype was O26 : H11 (14 %) and the most common seropathotype was B (45 %). The strains belonged mainly to phylogenetic group B1 (52 %). The distinct combinations of alleles across the seven MLST loci were used to define 13 sequence types among 19 STEC strains. PFGE typing of 20 STEC strains resulted in 19 pulsed-field patterns. Comparison of the patterns revealed 11 clusters (I–XI), each usually including strains belonging to different serotypes; one exception was cluster VI, which gathered exclusively seven strains of seropathotype B, clonal group enterohaemorrhagic E. coli (EHEC) 2 and phylogenetic group B1. In summary, STEC prevalence was low in Peruvian children with diarrhoea in the community setting. The strains were phylogenetically diverse and associated with mild infections. However, additional studies are needed in children with bloody diarrhoea and HUS. PMID:21292859

  5. Molecular Epidemiology of ESBL Genes and Multi-Drug Resistance in Diarrheagenic Escherichia Coli Strains Isolated from Adults in Iran

    PubMed Central

    Ghorbani-Dalini, Sadegh; Kargar, Mohammad; Doosti, Abbas; Abbasi, Pejman; Sarshar, Meysam

    2015-01-01

    Resistance to oxyimino cephalosporins antibiotics in Enterobacteriaceae is primarily done by the extended spectrum β-lactamases (ESBLs). Clear identification of risk factors for ESBLs-producing infections is necessary. Therefore, efficient strategies can be developed to decrease outbreak of these infections. The aim of this study was to determine the antibacterial susceptibility and ESBLs pattern of diarrhogenic Escherichia coli (E. coli) strains isolated from adult patients. In the present study, diarrheogenic E. coli strains were isolated from 54 patients from the University of Medical Sciences hospitals in Shiraz. Antimicrobial susceptibility testing was done by disk diffusion method by CLSI criteria. The presence of blaTEM, blaSHV and blaCTX-M genes was investigated by PCR using designated primers. The prevalence of ESBLs-producer E. coli strains was 12.96%. Antimicrobial resistance testing showed a high resistance to cefexime, trimethoprim-sulfamethoxazole, ampicillin and penicillin. Overall, β-lactamase genes were identified in 52 (96.30%) isolates which were identified as 45 (83.33%) blaTEM, 17 (31.48%) blaSHV and 11 (20.37%) blaCTX-M. ESBLs-producer E. coli is very prevalent in Diarrheogenic strains isolated from adult patients. Also, this study clearly showed that the blaTEM gene for ESBLs-producer E. coli was widespread in Iran. PMID:26664394

  6. Isolation and characterization of Escherichia coli mutants defective for phenylpropionate degradation.

    PubMed Central

    Burlingame, R P; Wyman, L; Chapman, P J

    1986-01-01

    Mutants of Escherichia coli defective in catabolism of 3-phenylpropionate, 3-(3-hydroxyphenyl)propionate, or both were isolated after mutagenesis with ethylmethane sulfonate. Nine phenotypically distinct classes of mutants were identified, including strains lacking each of the first five enzyme activities for the degradation of these compounds and mutants pleiotropically negative for some of these activities. Characterization of these mutants was greatly facilitated by the use of indicator media in which accumulation of 3-(2,3-dihydroxyphenyl)propionate or 2-hydroxy-6-ketononadienedioic acid led to the formation of dark red or bright yellow colors, respectively, in the medium. Assays with wild-type and mutant strains indicated that 3-phenylpropionate (or its dihydrodiol), but none of the hydroxylated derivatives tested, induced the synthesis of enzymes for its conversion to 3-(2,3-dihydroxyphenyl)propionate. The remaining enzymes were induced by the 2- or 3-hydroxy or 2,3-dihydroxy derivatives of 3-phenylpropionate, with the 2-hydroxy compound acting as an apparent gratuitous inducer. Metabolism to nonaromatic intermediates appeared to be unnecessary for full induction of any pathway enzyme. One unusual class of mutants, in which 2-keto-4-pentenoate hydratase appeared to be uninducible, indicated a level of control not previously shown in meta-fission catabolic pathways. PMID:3531186

  7. Screening and identification of new isolate: thermostable Escherichia coli with novel thermoalkalotolerant cellulases.

    PubMed

    Li, Xing-Hua; Bhaskar, Roy; Yang, Hua-Jun; Wang, Dan; Miao, Yun-Gen

    2009-10-01

    A cellulase-producing bacterium strain was isolated from soil that produced novel thermoalkalotolerant cellulases after growth on CMC-Na agar screening plate at 37 degrees C. It was identified as Escherichia coli using the method of 16S rRNA and intergenic spacer gene analysis combined with morphological, physiological, and biochemical tests. Three major components of the cellulases [carboxymethyl cellulase (CMCase), filter paper cellulase, and beta-glucosidase] were produced with maximal activities (0.23, 0.08, and 0.15 U/ml) and maximum specific activities 4.13, 0.56, and 0.50 U/mg protein after 72, 96, and 120 h growth, respectively. Maximum CMCase activity was measured at 50 degrees C and pH 6.0, respectively, and it also retained more than 60% of its maximal activity for at least 20 min at 50-70 degrees C and 10 min at 80 degrees C, respectively, and retained approximately 50% of its maximal activity after incubating at 90 degrees C for 10 min. The enzyme could be applied in bioconversion of lignocellulosic agricultural wastes.

  8. Virulence Profiles, Phylogenetic Background, and Antibiotic Resistance of Escherichia coli Isolated from Turkeys with Airsacculitis

    PubMed Central

    Cunha, Marcos Paulo Vieira; de Oliveira, Maria Gabriela Xavier; de Oliveira, Mirela Caroline Vilela; da Silva, Ketrin Cristina; Gomes, Cleise Ribeiro; Moreno, Andrea Micke; Knöbl, Terezinha

    2014-01-01

    Avian Pathogenic Escherichia coli (APEC) has been studied for decades because of its economic impact on the poultry industry. Recently, the zoonotic potential of APEC and multidrug-resistant strains have emerged. The aim of this study was to characterize 225 APEC isolated from turkeys presenting airsacculitis. The results showed that 92% of strains presented a multidrug-resistance (MDR), and the highest levels of resistance were to sulfamethazine (94%) and tetracycline (83%). Half of these strains were classified in phylogenetic group B2, followed by B1 (28.6%), A (17.1%), and D (4.8%). The prevalence of virulence genes was as follows: salmochelin (iroN, 95%), increased serum survival (iss, 93%), colicin V (cvi/cva, 67%), aerobactin (iucD, 67%), temperature-sensitive haemagglutinin (tsh, 56%), iron-repressible protein (irp2, 51%), invasion brain endothelium (ibeA, 31%), vacuolating autotransporter toxin (vat, 24%), K1 antigen (neuS, 19%), enteroaggregative heat-stable cytotoxin (astA, 17%), and pilus associated with pyelonephritis (papC, 15%). These results demonstrate that the majority of the investigated strains belonged to group B2 and were MDR. These data suggest that turkeys may serve as a reservoir of pathogenic and multidrug-resistance strains, reinforcing the idea that poultry plays a role in the epidemiological chain of ExPEC. PMID:25105155

  9. Isolation and genetic analysis of mutations allowing the degradation of furans and thiophenes by Escherichia coli.

    PubMed Central

    Abdulrashid, N; Clark, D P

    1987-01-01

    Successive mutations of Escherichia coli yielded a strain that was able to degrade a variety of heterocyclic oxygen- and sulfur-containing ring compounds. In particular, this strain could use both furan-2-carboxylic acid and thiophene-2-carboxylic acid as sole carbon and energy sources. Nitrogen-containing heterocyclic compounds were not degraded. This mutant was isolated by selecting first for oxidation of furan derivatives and then for thiophene degradation. Genetic analysis revealed that mutations in three novel genes, thdA (12 min), thdC (92 min), and thdD (98 min), were required for thiophene degradation. In addition, constitutively at both of the previously characterized fadR and atoC loci was required for efficient thiophene breakdown. The pathway of furan and thiophene degradation remains obscure, but the inability of our mutants to degrade 5-nitro- or 5-bromo-substituted furan derivatives suggests that hydroxylation at position 5 may be involved. Thiophene derivatives were toxic when they were present at concentrations of 0.1% or greater; however, addition of trace amounts of phenylalanine plus tyrosine greatly reduced this effect. PMID:3546268

  10. Relevant role of efflux pumps in high levels of rifaximin resistance in Escherichia coli clinical isolates.

    PubMed

    Gomes, C; Ruiz, L; Pons, M J; Ochoa, T J; Ruiz, J

    2013-09-01

    Enteropathogens have shown a high level of resistance against commonly used antibacterial drugs in Peru and it is necessary to explore alternative treatments. The aim of this study was to analyse the in vitro activity of rifaximin against diarrhoeagenic and commensal Escherichia coli in children less than 2 years of age. The minimal inhibitory concentration (MIC) to rifampicin and rifaximin was determined for 210 strains in the presence and absence of phenyl-arginine-β-naphthylamide (PAβN) and the mechanisms of resistance were investigated. The MIC levels ranged between 8 and >256 mg/litre and the predominant mechanism of resistance to rifaximin was the efflux pumps inhibited by PAβN in 95.2% of the isolates. The present MIC values are higher than those observed in other studies. Efflux pumps inhibited by PAβN were the cause of the rifaximin resistance in the majority of cases and suggest the presence of an environmental selective pressure. Consequently, rifaximin should be used with caution in the treatment of diarrhoea in Peru.

  11. Novel mcr-3 variant, encoding mobile colistin resistance, in an ST131 Escherichia coli isolate from bloodstream infection, Denmark, 2014

    PubMed Central

    Roer, Louise; Hansen, Frank; Stegger, Marc; Sönksen, Ute Wolff; Hasman, Henrik; Hammerum, Anette M

    2017-01-01

    A novel variant of the plasmid-borne colistin resistance gene mcr-3 was detected on an IncHI2 plasmid in an ST131 CTX-M-55-producing Escherichia coli isolate from a Danish patient with bloodstream infection in 2014. The discovery of novel plasmid-borne genes conferring resistance to colistin is of special interest since colistin has reemerged as an important drug in the treatment of infections with multidrug-resistant Gram-negative bacteria.

  12. NDM-5 Carbapenemase-Encoding Gene in Multidrug-Resistant Clinical Isolates of Escherichia coli from Algeria

    PubMed Central

    Sassi, Asma; Loucif, Lotfi; Gupta, Sushim Kumar; Dekhil, Mazouz; Chettibi, Houria

    2014-01-01

    Here, we report the first autochthonous cases of infections caused by blaNDM-5 New Delhi metallo-β-lactamase-producing Escherichia coli strains recovered from urine and blood specimens of three patients from Algeria between January 2012 and February 2013. The three isolates belong to sequence type 2659 and they coexpress blaCTX-M-15 with the blaTEM-1 and blaaadA2 genes. PMID:24982080

  13. Novel Streptomycin and Spectinomycin Resistance Gene as a Gene Cassette within a Class 1 Integron Isolated from Escherichia coli

    PubMed Central

    Sandvang, Dorthe

    1999-01-01

    The aadA genes, encoding resistance to streptomycin and spectinomycin, have been found as gene cassettes in different gram-negative and gram-positive bacterial species. The present study has revealed the sequence of a new gene, aadA5, integrated as a gene cassette together with the trimethoprim resistance gene dfr7 in a class 1 integron. The integron was located on a plasmid and was identified in a pathogenic porcine Escherichia coli isolate. PMID:10582907

  14. 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.

  15. [Prevalence and characterization of cefotaxime and ciprofloxacin co-resistant Escherichia coli isolates in retail chicken carcasses].

    PubMed

    Lin, Lan; Xu, Xiao; Ren, Xiu; Cui, Shenghui

    2014-09-01

    To investigate the prevalence and characteristics of cefotaxime in co-resistant Escherichia coli isolates in retail chicken samples and provide or the risk assessment and evaluation of new control measures of multi-drug i isolates in retail chicken products. Whole chicken carcasses re collected from Shanxi (n = 91), Guangdong (n = 63) and Inner 53) from April to December in 2011, cefotaxime and ciprofloxacin co- li isolates were recovered and subjected to phylogenetic group typing and usceptibility testing. All isolates were further characterized by screening for genes, quinolone resistance determinants by PCR and followed by DNA sis. Cefotaxime and ciprofloxacin co-resistant E. coli isolates in 35.7% (73/207) of retail chicken carcasses. E. coli isolates of oup A were dominant (61.6%, 45/73) and all the isolates showed tant profiles. The dominant resistant profiles were AMP-CAZ-CTX-CIP- (n =34) and AMP-CAZ-CTX-CIP-CHL-GEN-SXT-TET (n = 24). Point and ciprofloxac mutations in quinolone resistance determination, regions of topoisomerases were identified in all the isolates and most of the isolates accumulated three (n = 56) or four (n = 12) point mutations. Plasmid mediated quinolone resistant determinants were identified in 50 isolates, including oqxAB (n = 48) , aac(6')-Ib-cr (n = 5) , qnrS1 (n = 5) and qnrS2 (n = 3). Six subtypes of blaCTX-M were identified in 72 E. coli isolates and blaCTX-M-55 (n = 62) was dominant. Retail chicken could serve as an important reservoir of cefotaxime and ciprofloxacin co-resistant E. coli isolates.

  16. Indistinguishable NDM-producing Escherichia coli isolated from recreational waters, sewage, and a clinical specimen in Ireland, 2016 to 2017.

    PubMed

    Mahon, Bláthnaid M; Brehony, Carina; McGrath, Elaine; Killeen, James; Cormican, Martin; Hickey, Paul; Keane, Shane; Hanahoe, Belinda; Dolan, Ann; Morris, Dearbháile

    2017-04-13

    In this study, New Delhi metallo-beta-lactamase (NDM)-producing Enterobacteriaceae were identified in Irish recreational waters and sewage. Indistinguishable NDM-producing Escherichia coli by pulsed-field gel electrophoresis were isolated from sewage, a fresh water stream and a human source. NDM-producing Klebsiella pneumoniae isolated from sewage and seawater in the same area were closely related to each other and to a human isolate. This raises concerns regarding the potential for sewage discharges to contribute to the spread of carbapenemase-producing Enterobacteriaceae. This article is copyright of The Authors, 2017.

  17. 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

  18. 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

  19. Clinical isolates of uropathogenic Escherichia coli ST131 producing NDM-7 metallo-β-lactamase in China.

    PubMed

    Wang, Lian-Hui; Liu, Pan-Pan; Wei, Dan-Dan; Liu, Yang; Wan, La-Gen; Xiang, Tian-Xin; Zhang, Yu-Juan

    2016-07-01

    Here we report five cases of NDM-7-producing Escherichia coli from patients with bacteriuria in a teaching hospital in mainland China. Two isolates belonged to sequence type 131 (ST131), simultaneously carrying blaCTX-M-15, blaSHV-11, blaTEM-1 and qnrS1. The blaNDM-7 gene was located on a conjugative IncX3-type plasmid bearing blaTEM-1 and qnrS1. These findings indicate the spread of NDM-7 metallo-β-lactamase in a highly resistant and virulent E. coli sequence type in China.

  20. Prevalence of Antibiotic-Resistant Fecal Escherichia coli Isolates from Penned Broiler and Scavenging Local Chickens in Arusha, Tanzania.

    PubMed

    Rugumisa, Bernadether T; Call, Douglas R; Mwanyika, Gaspary O; Mrutu, Rehema I; Luanda, Catherine M; Lyimo, Beatus M; Subbiah, Murugan; Buza, Joram J

    2016-08-01

    We compared the prevalence of antibiotic-resistant Escherichia coli isolates from household-level producers of broiler (commercial source breeds) and local chickens in the Arusha District of Tanzania. Households were composed of a single dwelling or residence with independent, penned broiler flocks. Free-range, scavenging chickens were mixed breed and loosely associated with individual households. A total of 1,800 E. coli isolates (1,200 from broiler and 600 from scavenging local chickens) from 75 chickens were tested for their susceptibility against 11 antibiotics by using breakpoint assays. Isolates from broiler chickens harbored a higher prevalence of antibiotic-resistant E. coli relative to scavenging local chickens, including sulfamethoxazole (80.3 versus 34%), followed by trimethoprim (69.3 versus 27.7%), tetracycline (56.8 versus 20%), streptomycin (52.7 versus 24.7%), amoxicillin (49.6 versus 17%), ampicillin (49.1 versus 16.8%), ciprofloxacin (21.9 versus 1.7%), and chloramphenicol (1.5 versus 1.2%). Except for resistance to chloramphenicol, scavenging local chickens harbored fewer resistant E. coli isolates (P < 0.05). Broiler chickens harbored more isolates that were resistant to ≥7 antibiotics (P < 0.05). The higher prevalence of antibiotic-resistant E. coli from broiler chickens correlated with the reported therapeutic and prophylactic use of antibiotics in this poultry population. We suggest that improved biosecurity measures and increased vaccination efforts would reduce reliance on antibiotics by these households.

  1. Extended spectrum beta-lactamase and fluoroquinolone resistance genes and plasmids among Escherichia coli isolates from zoo animals, Czech Republic.

    PubMed

    Dobiasova, Hana; Dolejska, Monika; Jamborova, Ivana; Brhelova, Eva; Blazkova, Lucie; Papousek, Ivo; Kozlova, Marketa; Klimes, Jiri; Cizek, Alois; Literak, Ivan

    2013-09-01

    Commensal Escherichia coli isolates from healthy zoo animals kept in Ostrava Zoological Garden, Czech Republic, were investigated to evaluate the dissemination of extended-spectrum beta-lactamase (ESBL) and plasmid-mediated quinolone resistance (PMQR) genes. A total of 160 faecal samples of various animal species were inoculated onto MacConkey agar with cefotaxime (2 mg L(-1)) or ciprofloxacin (0.05 mg L(-1)) to obtain ESBL- or PMQR-positive E. coli isolates. Clonality of E. coli isolates was investigated by multilocus sequence typing and pulsed-field gel electrophoresis. Plasmids carrying ESBL or PMQR genes were typed by PCR-based replicon typing, plasmid multilocus sequence typing and restriction fragment length polymorphism. Forty-nine (71%, n = 69) cefotaxime-resistant and 15 (16%, n = 94) ciprofloxacin-resistant E. coli isolates harboured ESBL or PMQR genes. Isolates were assigned to 18 sequence types (ST) and 20 clusters according to their macrorestriction patterns by pulsed-field gel electrophoresis. The genes blaCTX -M-1 and qnrS1 were detected on highly related IncI1 plasmids assigned to clonal complex 3 (ST3, ST38) and on non-related IncN plasmids of ST1 and ST3, respectively. The gene qnrS1 was located on related IncX1 plasmids. Dissemination of antibiotic resistance is associated with spreading of particular E. coli clones and plasmids of specific incompatibility groups among various animal species.

  2. [Isolation and characterization of Escherichia coli O157 in bovine meat products and cattle in the province of Tucuman].

    PubMed

    Jure, María A; Condorí, Marina S; Pérez Terrazzino, Gabriela; Catalán, Mariana G; López Campo, Alejandro; Zolezzi, Gisella; Chinen, Isabel; Rivas, Marta; Castillo, Marta

    2015-01-01

    Escherichia coli O157 is an emergent pathogen associated with diarrhea, hemorrhagic colitis and hemolytic uremic syndrome. Meat products constitute an important transmission source of this microorganism. The aims of this study were to characterize E. coli O157 isolated from cattle and meat products collected from abattoirs and retail stores, to establish the clonal relatedness among regional isolates and to compare them with those in the national database. Between 2004 and 2013, 169 minced meat, 35 sausage and 216 carcass samples were analyzed. Thirteen E. coli O157 isolates were identified; 6 of which were O157:H7 and characterized as stx2c(vh-a)/eae/ehxA (n = 5) and stx2/eae/ehxA (n = 1). The 7 remaining isolates were non-toxigenic E. coli strains, and serotyped as O157:NT (n = 4), O157:NM (n = 1), O157:ND (n = 1) and O157:H16 (n = 1). The strains yielded different XbaI-PFGE patterns. Compared to the E. coli O157 isolates in the National Database, none of these patterns have been previously detected in strains of different origin in Argentina.

  3. Serotyping, antibiotic susceptibility, and virulence genes screening of Escherichia coli isolates obtained from diarrheic buffalo calves in Egyptian farms.

    PubMed

    Hakim, Ashraf S; Omara, Shimaa T; Syame, Sohier M; Fouad, Ehab A

    2017-07-01

    In Egypt as in many other countries, river water buffalo (Bubalus bubalis) is considered an important source of high-quality milk and meat supply. The objective of this study was to investigate serotypes, virulence genes, and antibiotic resistance determinants profiles of Escherichia coli isolated from buffalo at some places in Egypt; noticibly, this issue was not discussed in the country yet. A number of 58 rectal samples were collected from diarrheic buffalo calves in different regions in Egypt, and bacteriological investigated for E. coli existence. The E. coli isolates were biochemically, serologicaly identified, tested for antibiotic susceptibility, and polymerase chain reaction (PCR) analyzed for the presence of antibiotic resistance determinants and virulence genes. Overall 14 isolates typed as E. coli (24.1%); 6 were belonged to serogroup O78 (10.3%), followed by O125 (4 isolates, 6.9%), then O158 (3 isolates, 5.2%) and one isolate O8 (1.7%), among them, there were 5 E. coli isolates showed a picture of hemolysis (35.7%). The isolates exhibited a high resistance to β lactams over 60%, followed by sulfa (50%) and aminoglucoside (42.8%) group, in the same time the isolates were sensitive to quinolone, trimethoprim-sulfamethoxazole, tetracycline (100%), and cephalosporine groups (71.4%). A multiplex PCR was applied to the 14 E. coli isolates revealed that all were carrying at least one gene, as 10 carried blaTEM (71.4%), 8 Sul1 (57.1%), and 6 aadB (42.8%), and 9 isolates could be considered multidrug resistant (MDR) by an incidence of 64.3%. A PCR survey was stratified for the most important E. coli virulence genes, and showed the presence of Shiga toxins in 9 isolates carried either one or the two Stx genes (64.3%), 5 isolates carried hylA gene (35.7%), and eae in 2 isolates only (14.3%), all isolates carried at least one virulence gene except two (85.7%). The obtained data displayed that in Egypt, buffalo as well as other ruminants could be a potential

  4. Rapid Detection and Isolation of Escherichia coli O104:H4 from Milk Using Monoclonal Antibody-coated Magnetic Beads.

    PubMed

    Luciani, Mirella; Di Febo, Tiziana; Zilli, Katiuscia; Di Giannatale, Elisabetta; Armillotta, Gisella; Manna, Laura; Minelli, Fabio; Tittarelli, Manuela; Caprioli, Alfredo

    2016-01-01

    Monoclonal antibodies (MAbs) specific for the lipopolysaccharide (LPS) of Escherichia coli O104:H4 were produced by fusion of Sp2/O-Ag-14 mouse myeloma cells with spleen cells of Balb/c mice, immunized with heat-inactivated and sonicated E. coli O104:H4 bacterial cells. Four MAbs specific for the E. coli O104:H4 LPS (1E6G6, 1F4C9, 3G6G7, and 4G10D2) were characterized and evaluated for the use in a method for the detection of E. coli O104:H4 in milk samples that involves antibody conjugation to magnetic microbeads to reduce time and increase the efficiency of isolation. MAb 1E6G6 was selected and coupled to microbeads, then used for immuno-magnetic separation (IMS); the efficiency of the IMS method for E. coli O104:H4 isolation from milk was evaluated and compared to that of the EU RL VTEC conventional culture-based isolation procedure. Milk suspensions also containing other pathogenic bacteria that could potentially be found in milk (Campylobacter jejuni, Listeria monocytogenes, and Staphylococcus aureus) were also tested to evaluate the specificity of MAb-coated beads. Beads coated with MAb 1E6G6 showed a good ability to capture the E. coli O104:H4, even in milk samples contaminated with other bacteria, with a higher number of E. coli O104:H4 CFU reisolated in comparison with the official method (121 and 41 CFU, respectively, at 10(3) E. coli O104:H4 initial load; 19 and 6 CFU, respectively, at 10(2) E. coli O104:H4 initial load; 1 and 0 CFU, respectively, at 10(1) E. coli O104:H4 initial load). The specificity was 100%.

  5. Rapid Detection and Isolation of Escherichia coli O104:H4 from Milk Using Monoclonal Antibody-coated Magnetic Beads

    PubMed Central

    Luciani, Mirella; Di Febo, Tiziana; Zilli, Katiuscia; Di Giannatale, Elisabetta; Armillotta, Gisella; Manna, Laura; Minelli, Fabio; Tittarelli, Manuela; Caprioli, Alfredo

    2016-01-01

    Monoclonal antibodies (MAbs) specific for the lipopolysaccharide (LPS) of Escherichia coli O104:H4 were produced by fusion of Sp2/O-Ag-14 mouse myeloma cells with spleen cells of Balb/c mice, immunized with heat-inactivated and sonicated E. coli O104:H4 bacterial cells. Four MAbs specific for the E. coli O104:H4 LPS (1E6G6, 1F4C9, 3G6G7, and 4G10D2) were characterized and evaluated for the use in a method for the detection of E. coli O104:H4 in milk samples that involves antibody conjugation to magnetic microbeads to reduce time and increase the efficiency of isolation. MAb 1E6G6 was selected and coupled to microbeads, then used for immuno-magnetic separation (IMS); the efficiency of the IMS method for E. coli O104:H4 isolation from milk was evaluated and compared to that of the EU RL VTEC conventional culture-based isolation procedure. Milk suspensions also containing other pathogenic bacteria that could potentially be found in milk (Campylobacter jejuni, Listeria monocytogenes, and Staphylococcus aureus) were also tested to evaluate the specificity of MAb-coated beads. Beads coated with MAb 1E6G6 showed a good ability to capture the E. coli O104:H4, even in milk samples contaminated with other bacteria, with a higher number of E. coli O104:H4 CFU reisolated in comparison with the official method (121 and 41 CFU, respectively, at 103 E. coli O104:H4 initial load; 19 and 6 CFU, respectively, at 102 E. coli O104:H4 initial load; 1 and 0 CFU, respectively, at 101 E. coli O104:H4 initial load). The specificity was 100%. PMID:27379071

  6. High-virulence CMY-2- and CTX-M-2-producing avian pathogenic Escherichia coli strains isolated from commercial turkeys.

    PubMed

    da Silva, Ketrin Cristina; Cunha, Marcos Paulo Vieira; Cerdeira, Louise; de Oliveira, Maria Gabriela Xavier; de Oliveira, Mirela Caroline Vilela; Gomes, Cleise Ribeiro; Lincopan, Nilton; Knöbl, Terezinha; Moreno, Andrea Micke

    2017-01-01

    This study reports the high-virulence phylogenetic backgrounds of CMY-2- and CTX-M-2-producing avian pathogenic Escherichia coli strains isolated from turkeys sent to slaughter and condemned by airsacculitis in Brazil. Among 300 air sac samples, seven E. coli strains produced plasmid-mediated CMY-2-type AmpC, of which three carried also the blaCTX-M-2 Extended Spectrum Beta-Lactamase encoding gene. Interestingly, the transfer of the blaCMY-2 gene was positive for three E. coli strains, being associated with the presence of IncI1 plasmids. The complete sequence of the representative pJB10 plasmid revealed that the blaCMY-2 gene was within a transposon-like element in the classical genetic environment consisting of tnpA-blaCMY-2-blc-sugE structure. This plasmid with 94-kb belonged to the sequence type (ST) 12 among IncI1 plasmids, which has been associated with the worldwide spread of blaCMY-2 among Salmonella enterica and E. coli. Furthermore, to the best of our knowledge, this is the first complete sequence of a CMY-2-encoding plasmid derived from an Escherichia coli isolated from food-producing animals in Latin America.

  7. Rapid, Multiplexed Characterization of Shiga Toxin-Producing Escherichia coli (STEC) Isolates Using Suspension Array Technology

    PubMed Central

    Carter, John M.; Lin, Andrew; Clotilde, Laurie; Lesho, Matthew

    2016-01-01

    Molecular methods have emerged as the most reliable techniques to detect and characterize pathogenic Escherichia coli. These molecular techniques include conventional single analyte and multiplex PCR, PCR followed by microarray detection, pulsed-field gel electrophoresis (PFGE), and whole genome sequencing. The choice of methods used depends upon the specific needs of the particular study. One versatile method involves detecting serogroup-specific markers by hybridization or binding to encoded microbeads in a suspension array. This molecular serotyping method has been developed and adopted for investigating E. coli outbreaks. The major advantages of this technique are the ability to simultaneously serotype E. coli and detect the presence of virulence and pathogenicity markers. Here, we describe the development of a family of multiplex molecular serotyping methods for Shiga toxin-producing E. coli, compare their performance to traditional serotyping methods, and discuss the cost-benefit balance of these methods in the context of various food safety objectives. PMID:27242670

  8. Molecular characterization of antimicrobial resistance in enterococci and Escherichia coli isolates from European wild rabbit (Oryctolagus cuniculus).

    PubMed

    Silva, Nuno; Igrejas, Gilberto; Figueiredo, Nicholas; Gonçalves, Alexandre; Radhouani, Hajer; Rodrigues, Jorge; Poeta, Patrícia

    2010-09-15

    A total of 44 Escherichia coli and 64 enterococci recovered from 77 intestinal samples of wild European rabbits in Portugal were analyzed for resistance to antimicrobial agents. Resistance in E. coli isolates was observed for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, gentamicin, tobramycin, nalidixic acid, ciprofloxacin and chloramphenicol. None of the E. coli isolates produced extended-spectrum beta-lactamases (ESBLs). The bla(TEM), aadA, aac(3)-II, tet(A) and/or tet(B), and the catA genes were demonstrated in all ampicillin, streptomycin, gentamicin, tetracycline, and chloramphenicol-resistant isolates respectively, and the sul1 and/or sul2 and/or sul3 genes in 4 of 5 sulfamethoxazole/trimethoprim resistant isolates. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (39 isolates), followed by E. faecium (21 isolates) and E. hirae (4 isolates). More than one-fourth (29.7%) of the isolates were resistant to tetracycline; 20.3% were resistant to erythromycin, 14.1% were resistant to ciprofloxacin and 10.9% were resistant to high-level-kanamycin. Lower level of resistance (<10%) was detected for ampicillin, quinupristin/dalfopristin and high-level-gentamicin, -streptomycin. No vancomycin-resistance was detected in the enterococci isolates. Resistance genes detected included aac(6')-aph(2''), ant(6)-Ia, tet(M) and/or tet(L) in all gentamicin, streptomycin and tetracycline-resistant isolates respectively. The aph(3')-IIIa gene was detected in 6 of 7 kanamycin-resistant isolates, the erm(B) gene in 11 of 13 erythromycin-resistant isolates and the vat(D) gene in the quinupristin/dalfopristin-resistant E. faecium isolate. This survey showed that faecal bacteria such as E. coli and enterococci of wild rabbits could be a reservoir of antimicrobial resistance genes.

  9. Genetic features of human and bovine Escherichia coli O157:H7 strains isolated in Argentina.

    PubMed

    Pianciola, L; D'Astek, B A; Mazzeo, M; Chinen, I; Masana, M; Rivas, M

    2016-02-01

    Shiga toxin-producing Escherichia coli (STEC) are important food-borne pathogens associated with human diseases. In Argentina, O157:H7 is the dominant serotype in hemolytic uremic syndrome (HUS) cases. Previously, we have described the almost exclusive circulation of human E. coli O157 strains belonging to the hypervirulent clade 8 in Neuquén Province. The aim of the present study was to investigate, by a broad molecular characterization, if this particular distribution of E. coli O157 clades in Neuquén is similar to the situation in other regions of the country and if it may be originated in a similar profile in cattle, its main reservoir. Two-hundred and eighty O157 strains (54 bovine and 226 human) isolated between 2006 and 2008 in different regions of Argentina were studied. All strains harbored rfbO157, fliCH7, eae, and ehxA genes. The predominant genotype was stx2a/stx2c in human (76.1%) and bovine (55.5%) strains. All human isolates tested by Lineage-Specific Polymorphism Assay (LSPA-6), were lineage I/II; among bovine strains, 94.1% belonged to lineage I/II and 5.9% to lineage I. No LSPA-6 lineage II isolates were detected. Single nucleotide polymorphism (SNP) analysis has revealed the existence of nine clade phylogenetic groups. In our clinical strains collection, 87.6% belonged to the hypervirulent clade 8, and 12.4% were classified as clade 4/5. In bovine isolates, 59.3% strains were clade 8, 33.3% clade 4/5 and 7.4% clade 3. More than 80% of human strains showed the presence of 6 of the 7 virulence determinants described in the TW14359 O157 strain associated with the raw spinach outbreak in the U.S. in 2006. More than 80% of bovine strains showed the presence of 3 of these factors. The q933 allele, which has been related to high toxin production, was present in 98.2% of clinical strains and 75.9% of the bovine isolates. The molecular characterization of human STEC O157 strains allows us to conclude that the particular situation previously described

  10. 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.

  11. Characterization of Monkey Enteropathogenic Escherichia coli (EPEC) and Human Typical and Atypical EPEC Serotype Isolates from Neotropical Nonhuman Primates

    PubMed Central

    Carvalho, Vania M.; Gyles, Carlton L.; Ziebell, Kim; Ribeiro, Marcela A.; Catão-Dias, José L.; Sinhorini, Idércio L.; Otman, Jamile; Keller, Rogéria; Trabulsi, Luiz R.; Pestana de Castro, Antônio F.

    2003-01-01

    Enteropathogenic Escherichia coli (EPEC) has been associated with infantile diarrhea and mortality in humans in developing countries. While diarrhea is also a major problem among primates kept in captivity, the role of E. coli is unclear. This study was designed to characterize diarrheagenic E. coli recovered from the feces of 56 New World nonhuman primates, primarily marmosets (Callithrix spp.). Seventeen of the 56 primates had signs of diarrhea and/or enteritis. E. coli recovered from feces from these animals was tested by PCR for genes encoding virulence factors of diarrheagenic E. coli and for patterns of adherence to HeLa cells. In addition, isolates were characterized by the fluorescence actin staining test and by their ability to induce attaching and effacing lesions. PCR for the eae gene was positive in 10 of the 39 (27%) apparently healthy animals and in 8 of the 17 (47%) animals with diarrhea and/or enteritis. Colonies of eae+ E. coli were serotyped and examined by PCR for genes encoding EPEC virulence markers. The eae+ E. coli isolates recovered from both healthy and sick nonhuman primates demonstrated virulence-associated attributes similar to those of EPEC strains implicated in human disease and are designated monkey EPEC. The results presented here indicate that EPEC may be a significant pathogen for nonhuman primates, deserving further investigation. The similarities between the affected animals investigated in this study and human EPEC infections suggest that marmosets may represent an important model for EPEC in humans. PMID:12624055

  12. 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.

  13. Frequency distribution of virulence factors in uropathogenic Escherichia coli isolated from Kermanshah in 2011-2012

    PubMed Central

    Mohajeri, Parviz; Khademi, Hosna; Ebrahimi, Roya; Farahani, Abbas; Rezaei, Mansour

    2014-01-01

    Background: Uropathogenic Escherichia coli (UPEC) can cause urinary tract infection (UTI). To prevent urine flow lavage, UPEC has acquired several virulence factors called adhesins. These adhesins are expressed and controlled by different genes. Aim: This study was aimed to determine some of the most important genes that control virulence factors of UPEC (pyelonephritis associated pili [pap], S fimbrial adhesion [sfa] and A fimbrial adhesion [afa] genes), which code for adhesins and phenotypic factors. Materials and Methods: In total, 205 UPEC isolates from in- and out-patients with UTI were obtained. Polymerase chain reaction was used for gene amplification. One drop of bacterial suspension, one of red blood cells and one of peripheral blood smear were mixed for hemagglutination (HA). Formation of a clump was considered to be positive. Bacteria were grown on blood agar to determine hemolysis. Surface hydrophobicity was determined using the SAT test. Result: Frequencies of pap, afa and sfa were 42 (20.5%), 17 (8.3%) and 44 (21.5%), respectively. Frequencies of HA, hemolysis and hydrophobicity were 138 (67.3%), 56 (27.3%) and 39 (19%), respectively. Among HA-positive bacteria, 103 (74.6%) were mannose resistant. Our results highlight higher frequency of HA than that of other virulence factors, indicating a crucial role of this virulence factor in UPEC. Discussion: We concluded that major differences exist in the prevalence of virulence factors among different UPEC isolated from different countries. The association observed between pathogenicity and virulence factors may promote UPEC survival and growth within the urinary tract. Detecting these genes as the primary controllers of UPEC virulence factors may aid in better management of related infections. PMID:25143887

  14. Genomic fingerprints of Escherichia coli strains isolated from surface water in Alborz province, Iran.

    PubMed

    Ranjbar, Reza; Pezeshknejad, Parichehr; Khamesipour, Faham; Amini, Kiumars; Kheiri, Roohollah

    2017-07-20

    Consistent use of suitable diagnostic methods is essential to evaluate the genomic diversity of E. coli strains. Advance of efficient methods to discriminate the causes of E. coli in aquatic environments is important. This study aimed to describe the strain diversity of an E. coli population retrieved from surface water. One hundred water samples were drawn within a period of 1 year, from May 2012 to May 2013, and E. coli bacteria have been isolated from water samples. The genomic diversity analysis of 100 isolates of E. coli (one isolate per sample) has been carried out with the use of the ERIC-PCR fingerprinting method. Overall, our data indicated that complex fingerprint patterns have been obtained for totally of the isolates. Highest number of strains were in E4 (20 strains with more than 20% similarity) and lowest number of strains were in E3 (5 strains) group. In addition, there was no similarity in E1 (9 strains), E8 (10 strains) and E9 (7 strains) clusters. Therefore, the occurrence of potential pathogenic E. coli and diversity of E. coli strains in surface water in Alborz province, Iran could pose a possible risk to animal health and human if not disinfected well.

  15. Host Characteristics and Bacterial Traits Predict Experimental Virulence for Escherichia coli Bloodstream Isolates From Patients With Urosepsis.

    PubMed

    Johnson, James R; Porter, Stephen; Johnston, Brian; Kuskowski, Michael A; Spurbeck, Rachel R; Mobley, Harry L T; Williamson, Deborah A

    2015-09-01

    Background.  Extraintestinal Escherichia coli infections are common, costly, and potentially serious. A better understanding of their pathogenesis is needed. Methods.  Sixty-seven E coli bloodstream isolates from adults with urosepsis (Seattle, WA; 1980s) underwent extensive molecular characterization and virulence assessment in 2 infection models (murine subcutaneous sepsis and moth larval lethality). Statistical comparisons were made among host characteristics, bacterial traits, and experimental virulence. Results.  The 67 source patients were diverse for age, sex, and underlying medical and urological conditions. The corresponding E coli isolates exhibited diverse phylogenetic backgrounds and virulence profiles. Despite the E coli isolates' common bloodstream origin, they exhibited a broad range of experimental virulence in mice and moth larvae, in patterns that (for the murine model only) corresponded significantly with host characteristics and bacterial traits. The most highly mouse-lethal strains were enriched with classic "urovirulence" traits and typically were from younger women with anatomically and functionally normal urinary tracts. The 2 animal models corresponded poorly with one another. Conclusions.  Host compromise, including older age and urinary tract abnormalities, allows comparatively low-virulence E coli strains to cause urosepsis. Multiple E coli traits predict both experimental and epidemiological virulence. The larval lethality model cannot be a substitute for the murine sepsis model.

  16. Prevalence of CTX-M-Type extended-spectrum β-lactamases in Escherichia coli strains isolated in poultry farms.

    PubMed

    Abreu, Rossana; Castro, Beatriz; Espigares, Elena; Rodríguez-Álvarez, Cristobalina; Lecuona, María; Moreno, Elena; Espigares, Miguel; Arias, Angeles

    2014-11-01

    The aim of the study was to detect the prevalence of CTX-M-type extended-spectrum β-lactamases (ESBL) in Escherichia coli strains isolated in healthy chickens at poultry farms in Tenerife, Spain. From November 2012 to February 2013, 260 live chickens were screened. Samples were cultured in chromogenic media. Suspect strains were identified by Vitek 2 system and ESBL production was confirmed by the double-disk synergy test. Pulsed-field gel electrophoresis (PFGE) was performed with XbaI (Promega, Madison, WI) to ESBL-E. coli isolates. The presence of CTX-M-type was detected by real-time polymerase chain reaction. Of 260 rectal swabs, 237 (91.1%) were ESBL-E. coli, 196 (75.38%) strains were characterized by PFGE, and CTX-M-type was detected in 116 (59.1%) of these strains. With respect to the susceptibility patterns of E. coli blaCTX-M strains, 7.8% showed resistance to more than two non-β-lactam antibiotics. In our area, the prevalence of CTX-M-type in E. coli isolated in chicken was even higher than those found in other countries. The impact of food animals as a possible reservoir for ESBL-E. coli, especially CTX-M-type ESBL, and the dissemination of such strains into the food production chain need to be assessed.

  17. MOLECULAR DETECTION OF ANTIBIOTIC-RESISTANCE DETERMINANTS IN ESCHERICHIA COLI ISOLATED FROM THE ENDANGERED AUSTRALIAN SEA LION (NEOPHOCA CINEREA).

    PubMed

    Delport, Tiffany C; Harcourt, Robert G; Beaumont, Linda J; Webster, Koa N; Power, Michelle L

    2015-07-01

    Greater interaction between humans and wildlife populations poses significant risks of anthropogenic impact to natural ecosystems, especially in the marine environment. Understanding the spread of microorganisms at the marine interface is therefore important if we are to mitigate adverse effects on marine wildlife. We investigated the establishment of Escherichia coli in the endangered Australian sea lion (Neophoca cinerea) by comparing fecal isolation from wild and captive sea lion populations. Fecal samples were collected from wild colonies March 2009-September 2010 and from captive individuals March 2011-May 2013. Using molecular screening, we assigned a phylotype to E. coli isolates and determined the presence of integrons, mobile genetic elements that capture gene cassettes conferring resistance to antimicrobial agents common in fecal coliforms. Group B2 was the most abundant phylotype in all E. coli isolates (n = 37), with groups A, B1, and D also identified. Integrons were not observed in E. coli (n = 21) isolated from wild sea lions, but were identified in E. coli from captive animals (n = 16), from which class I integrases were detected in eight isolates. Sequencing of gene cassette arrays identified genes conferring resistance to streptomycin-spectinomycin (aadA1) and trimethoprim (dfrA17, dfrB4). Class II integrases were not detected in the E. coli isolates. The frequent detection in captive sea lions of E. coli with resistance genes commonly identified in human clinical cases suggests that conditions experienced in captivity may contribute to establishment. Identification of antibiotic resistance in the microbiota of Australian sea lions provides crucial information for disease management. Our data will inform conservation management strategies and provide a mechanism to monitor microorganism dissemination to sensitive pinniped populations.

  18. Prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli isolated from animals, foods and humans in Iceland.

    PubMed

    Thorsteinsdottir, T R; Haraldsson, G; Fridriksdottir, V; Kristinsson, K G; Gunnarsson, E

    2010-05-01

    The prevalence of resistant bacteria in food products in Iceland is unknown, and little is known of the prevalence in production animals. The aim of this study was to investigate the prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli from healthy pigs and broiler chicken, pork, broiler meat, slaughterhouse personnel and outpatients in Iceland. A total of 419 E. coli isolates were tested for antimicrobial susceptibility using a microbroth dilution method (VetMIC), and resistant strains were compared using pulsed-field gel electrophoresis (PFGE). All samples were screened for enrofloxacin-resistant strains with selective agar plates. The resistance rates among E. coli isolates were moderate to high from caecal and meat samples of pigs (54.1% and 28%), broilers (33.6% and 52%) and slaughterhouse personnel (39.1%), whereas isolates from outpatients showed moderate resistance rates (23.1%). Of notice was resistance to quinolones (minimum inhibitory concentrations: nalidixic acid > or = 32, ciprofloxacin > or = 0.12 and enrofloxacin > or = 0.5), particularly among broiler and broiler meat isolates (18.2% and 36%), as there is no known antimicrobial selection pressure in the broiler production in Iceland. The majority (78.6%) of the resistant E. coli isolates was genotypically different, based on PFGE fingerprint analyses and clustering was limited. However, the same resistance pattern and pulsotype were found among isolates from broiler meat and a slaughterhouse worker, indicating spread of antimicrobial-resistant E. coli from animals to humans. Diverse resistance patterns and pulsotypes suggest the presence of a large population of resistant E. coli in production animals in Iceland. This study gives baseline information on the prevalence of antimicrobial-resistant E. coli from production animals, and their food products in Iceland and the moderate to high resistance rates emphasize the need for continuing surveillance. Further studies on the

  19. Prevalence of Qnr determinants among bloodstream isolates of Escherichia coli and Klebsiella pneumoniae in a Taiwanese hospital, 1999-2005.

    PubMed

    Wu, Jiunn-Jong; Ko, Wen-Chien; Wu, Hsiu-Mei; Yan, Jing-Jou

    2008-06-01

    To determine the prevalence and characteristics of bloodstream isolates of Escherichia coli and Klebsiella pneumoniae with qnr genes in a Taiwanese hospital. A total of 2035 E. coli and 1147 K. pneumoniae isolates collected between 1999 and 2005 were screened for qnrA, qnrB and qnrS by PCR and colony hybridization. Beta-lactamase genes, genetic relatedness and transferability were examined by PCR, PFGE and conjugation, respectively. The prevalence of qnr genes was 7.8% and 0.6% for K. pneumoniae and E. coli, respectively. The prevalence rates of qnrB2, qnrB4 and qnrS1 genes for K. pneumoniae were 2.3%, 3.6% and 2.8%, respectively, and for E. coli were 0.2%, 0% and 0.4%, respectively. The prevalence of qnrB4 in K. pneumoniae increased remarkably from 0% to 7.6% over the 7 study years. qnrA was not detected. Overall, the SHV-5-related, CTX-M-14, CTX-M-3, CMY-2, DHA-1 and IMP-8 beta-lactamases were detected alone or in combination in 82.0% of qnr-positive K. pneumoniae isolates and 41.7% of qnr-positive E. coli isolates. Notably, all qnrB4-positive isolates possessed the DHA-1 enzyme, and the majority of the qnrB2-positive isolates (E. coli, 100%; K. pneumoniae, 80.8%) produced SHV-5-related beta-lactamases. Genetic diversity was demonstrated by PFGE. Conjugation experiments revealed co-transfer of bla(SHV-12), bla(DHA-1) and bla(SHV-5) with qnrB2, qnrB4 and qnrS1, respectively. qnr genes remained rare in E. coli but appeared to be increasing in K. pneumoniae in our hospital. Horizontal transfer may play a major role in the intra-hospital spread of qnr.

  20. Large Scale Analysis of Virulence Genes in Escherichia coli Strains Isolated from Avalon Bay, CA

    PubMed Central

    Hamilton, Matthew J.; Hadi, Asbah Z.; Griffith, John F.; Ishii, Satoshi; Sadowsky, Michael J.

    2010-01-01

    Contamination of recreational waters with E. coli and Enterococcus sp. is a widespread problem resulting in beach closures and loss of recreational activity. While E. coli is frequently used as an indicator of fecal contamination, and has been extensively measured in waterways, few studies have examined the presence of potentially pathogenic E. coli strains in beach waters. In this study, a combination of high-throughput, robot-assisted colony hybridization and PCR-based analyses were used to determine the genomic composition and frequency of virulence genes present in E. coli isolated from beach water in Avalon Bay, Santa Catalina Island, CA. A total of 24,493 E. coli isolates were collected from two sites at a popular swimming beach between August through September 2007 and from July through August 2008. All isolates were examined for the presence of shiga-like toxins (stx1/stx2), intimin (eaeA), and enterotoxins (ST/LT). Of the 24,493 isolates examined, 3.6% contained the eaeA gene, indicating that these isolates were potential EPEC strains. On five dates, however, greater than 10% of the strains were potential EPEC, suggesting that incidence of virulence genes at this beach has a strong temporal component. No STEC or ETEC isolates were detected, and only eight (<1.0%) of the potential EPEC isolates were found to carry the EAF plasmid. The potential EPEC isolates mainly belonged to E. coli phylogenetic groups B1 or B2, and carried the beta intimin subtype. DNA fingerprint analyses of the potential EPEC strains indicated that the isolates belonged to several genetically diverse groups, although clonal isolates were frequently detected. While the presence of virulence genes alone cannot be used to determine the pathogenicity of strains, results from this study show that potential EPEC strains can be found in marine beach water and their presence needs to be considered as one of the factors used in decisions concerning beach closures. PMID:20643468

  1. Fluoroquinolone-resistance mechanisms and phylogenetic background of clinical Escherichia coli strains isolated in south-east Poland.

    PubMed

    Korona-Glowniak, Izabela; Skrzypek, Kinga; Siwiec, Radosław; Wrobel, Andrzej; Malm, Anna

    2016-07-01

    Fluorochinolones are a class of broad-spectrum antimicrobials in the treatment of several infections, including those caused by Escherichia coli. Due to the increasing resistance of bacteria to antimicrobials, an understanding of fluoroquinolone resistance is important for infection control. The aim of this study was to determine susceptibility of clinical E. coli strains to fluoroquinolones and characterize their mechanisms of quinolone resistance. Totally, 79 non-duplicate clinical E. coli isolates included in this study were mainly from skin lesion -36 (45.6%) isolates; 54 (68.4%) isolates were assigned to phylogenetic B2 group. Resistance to ciprofloxacin was found in 20 isolates. In the quinolone resistance-determining region (QRDR) region of gyrA and parC, 4 types of point mutations were detected. Mutations in parC gene were found in all strains with gyrA mutations. Predominance of double mutation in codon 83 and 87 of gyrA (90%) and in codon 80 of parC (90%) was found. Moreover, plasmid-mediated quinolone resistance (PMRQ) determinants (qnrA or qnrB and/or aac(6')-Ib-cr) were present in 5 (25%) out of 20 fluoroquinolone-resistant isolates. Resistance to fluoroquinolones in all of the tested clinical E. coli isolates correlated with point mutations in both gyrA and parC. The majority of fluoroquinolone-resistant strains belonged to D and B2 phylogenetic groups.

  2. Association between alpha-hemolysin production and HeLa cell-detaching activity in fecal isolates of Escherichia coli.

    PubMed Central

    Marques, L R; Abe, C M; Griffin, P M; Gomes, T A

    1995-01-01

    Escherichia coli isolates that cause detachment of cell monolayers during in vitro adherence assays (cell-detaching E. coli [CDEC]) were recently reported as a potential new group of enteropathogenic bacteria. In the present study, 269 E. coli isolates from feces of children 1 to 5 years of age were identified as CDEC in a detaching assay developed with HeLa cells. The great majority of these isolates were hemolytic within 3 h of growth on blood agar plates and hybridized with a DNA probe for alpha-hemolysin (93.7%), while most of the non-detaching isolates were hemolytic within 24 h (3.6%) or nonhemolytic (94.8%). E. coli isolates that produced alpha-hemolysin were found in 60 (30%) of 200 children with diarrhea and 47 (24%) of 200 age-matched controls. No statistical significance was found for the differences in alpha-hemolysin production among the matched pairs (P = 0.2). These data suggest that CDEC isolates are not associated with diarrhea in the population studied. PMID:8567910

  3. Antibiotic resistance patterns of Escherichia coli isolates from different aquatic environmental sources in León, Nicaragua.

    PubMed

    Amaya, E; Reyes, D; Paniagua, M; Calderón, S; Rashid, M-U; Colque, P; Kühn, I; Möllby, R; Weintraub, A; Nord, C E

    2012-09-01

    Antibiotic-resistant bacteria have emerged due to the selective pressure of antimicrobial use in humans and animals. Water plays an important role in dissemination of these organisms among humans, animals and the environment. We studied the antibiotic resistance patterns among 493 Escherichia coli isolates from different aquatic environmental sources collected from October 2008 to May 2009 in León, Nicaragua. High levels of antibiotic resistance were found in E. coli isolates in hospital sewage water and in eight of 87 well-water samples. Among the resistant isolates from the hospital sewage, ampicillin, chloramphenicol, ciprofloxacin, nalidixic acid, trimethoprim-sulphamethoxazole was the most common multi-resistance profile. Among the resistant isolates from the wells, 19% were resistant to ampicillin, ceftazidime, ceftriaxone, cefotaxime, chloramphenicol, ciprofloxacin, gentamicin, nalidixic acid and trimethoprim-sulphamethoxazole. E. coli producing ESBL and harbouring bla(CTX-M) genes were detected in one of the hospital sewage samples and in 26% of the resistant isolates from the well-water samples. The bla(CTX-M-9) group was more prevalent in E. coli isolates from the hospital sewage samples and the bla(CTX-M-1) group was more prevalent in the well-water samples.

  4. Diarrheagenic Escherichia coli.

    PubMed

    Gomes, Tânia A T; Elias, Waldir P; Scaletsky, Isabel C A; Guth, Beatriz E C; Rodrigues, Juliana F; Piazza, Roxane M F; Ferreira, Luís C S; Martinez, Marina B

    2016-12-01

    Most Escherichia coli strains live harmlessly in the intestines and rarely cause disease in healthy individuals. Nonetheless, a number of pathogenic strains can cause diarrhea or extraintestinal diseases both in healthy and immunocompromised individuals. Diarrheal illnesses are a severe public health problem and a major cause of morbidity and mortality in infants and young children, especially in developing countries. E. coli strains that cause diarrhea have evolved by acquiring, through horizontal gene transfer, a particular set of characteristics that have successfully persisted in the host. According to the group of virulence determinants acquired, specific combinations were formed determining the currently known E. coli pathotypes, which are collectively known as diarrheagenic E. coli. In this review, we have gathered information on current definitions, serotypes, lineages, virulence mechanisms, epidemiology, and diagnosis of the major diarrheagenic E. coli pathotypes. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  5. 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.