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Sample records for enterococcus faecium clones

  1. Individual variability in finger-to-finger transmission efficiency of Enterococcus faecium clones

    PubMed Central

    del Campo, Rosa; Sánchez-Díaz, Ana María; Zamora, Javier; Torres, Carmen; Cintas, Luis María; Franco, Elvira; Cantón, Rafael; Baquero, Fernando

    2014-01-01

    A fingertip-to-fingertip intraindividual transmission experiment was carried out in 30 healthy volunteers, using four MLST-typed Enterococcus faecium clones. Overall results showed an adequate fit goodness to a theoretical exponential model, whereas four volunteers (13%) exhibited a significantly higher finger-to-finger bacterial transmission efficiency. This observation might have deep consequences in nosocomial epidemiology. PMID:24382843

  2. Longer Intestinal Persistence of Enterococcus faecalis Compared to Enterococcus faecium Clones in Intensive-Care-Unit Patients▿

    PubMed Central

    Ruiz-Garbajosa, Patricia; del Campo, Rosa; Coque, Teresa M.; Asensio, Angel; Bonten, Marc; Willems, Rob; Baquero, Fernando; Cantón, Rafael

    2009-01-01

    The dynamics of intestinal colonization with enterococcal clones in intensive-care-unit (ICU) patients was evaluated. Eight patients admitted directly to the neurosurgical ICU at the Ramón y Cajal University Hospital (Madrid, Spain) from the community and with no overlapping stay during a 10-month period in 2006 were studied. Rectal swab specimens were collected on admission and daily until the patients were discharged. Clonality was determined by pulsed-field gel electrophoresis and multilocus sequence typing. Clonal colonization dynamics were estimated by using two new parameters: the clonal diversity per patient per day (CDPD) and the clonal persistence ratio (CPR). Enterococcus faecalis isolates (n = 123) and Enterococcus faecium isolates (n = 66) were resolved into 13 and 15 clones, respectively. The CDPD of E. faecalis steadily increased during admission, and E. faecalis showed a higher (P = 0.001) CPR value than E. faecium (0.86 and 0.42, respectively). E. faecium, with the exception of an ampicillin-resistant clone belonging to clonal complex 17, frequently appeared as a short-term colonizer, even though the E. faecalis clones had significantly (P = 0.03) more days under antibiotic exposure than E. faecium (77.5 and 65 days/100 colonization days, respectively). E. faecalis had a longer persistence than E. faecium, except for the CC17 ampicillin-resistant clone, and E. faecalis showed a cumulative increase in CDPD, whereas E. faecium did not. CDPD and CPR were useful for measuring the dynamics of intestinal colonization with enterococcal clones. PMID:19052172

  3. Evolutionary origins of the emergent ST796 clone of vancomycin resistant Enterococcus faecium

    PubMed Central

    Buultjens, Andrew H.; Lam, Margaret M.C.; Ballard, Susan; Monk, Ian R.; Mahony, Andrew A.; Grabsch, Elizabeth A.; Grayson, M. Lindsay; Pang, Stanley; Coombs, Geoffrey W.; Robinson, J. Owen; Seemann, Torsten; Howden, Benjamin P.

    2017-01-01

    From early 2012, a novel clone of vancomycin resistant Enterococcus faecium (assigned the multi locus sequence type ST796) was simultaneously isolated from geographically separate hospitals in south eastern Australia and New Zealand. Here we describe the complete genome sequence of Ef_aus0233, a representative ST796 E. faecium isolate. We used PacBio single molecule real-time sequencing to establish a high quality, fully assembled genome comprising a circular chromosome of 2,888,087 bp and five plasmids. Comparison of Ef_aus0233 to other E. faecium genomes shows Ef_aus0233 is a member of the epidemic hospital-adapted lineage and has evolved from an ST555-like ancestral progenitor by the accumulation or modification of five mosaic plasmids and five putative prophage, acquisition of two cryptic genomic islands, accrued chromosomal single nucleotide polymorphisms and a 80 kb region of recombination, also gaining Tn1549 and Tn916, transposons conferring resistance to vancomycin and tetracycline respectively. The genomic dissection of this new clone presented here underscores the propensity of the hospital E. faecium lineage to change, presumably in response to the specific conditions of hospital and healthcare environments. PMID:28149688

  4. Identification of a novel clone, ST736, among Enterococcus faecium clinical isolates and its association with daptomycin nonsusceptibility.

    PubMed

    Wang, Guiqing; Kamalakaran, Sitharthan; Dhand, Abhay; Huang, Weihua; Ojaimi, Caroline; Zhuge, Jian; Yee, Leslie Lee; Mayigowda, Pramod; Surendraiah, Pavan Kumar Makam; Dimitrova, Nevenka; Fallon, John T

    2014-08-01

    Resistance to daptomycin in enterococcal clinical isolates remains rare but is being increasingly reported in the United States and worldwide. There are limited data on the genetic relatedness and microbiological and clinical characteristics of daptomycin-nonsusceptible enterococcal clinical isolates. In this study, we assessed the population genetics of daptomycin-nonsusceptible Enterococcus faecium (DNSE) clinical isolates by multilocus sequence typing (MLST) and whole-genome sequencing analysis. Forty-two nonduplicate DNSE isolates and 43 randomly selected daptomycin-susceptible E. faecium isolates were included in the analysis. All E. faecium isolates were recovered from patients at a tertiary care medical center in suburban New York City from May 2009 through December 2013. The daptomycin MICs of the DNSE isolates ranged from 6 to >256 μg/ml. Three major clones of E. faecium (ST18, ST412, and ST736) were identified among these clinical isolates by MLST and whole-genome sequence-based analysis. A newly recognized clone, ST736, was seen in 32 of 42 (76.2%) DNSE isolates and in only 14 of 43 (32.6%) daptomycin-susceptible E. faecium isolates (P < 0.0001). This report provides evidence of the association between E. faecium clone ST736 and daptomycin nonsusceptibility. The identification and potential spread of this novel E. faecium clone and its association with daptomycin nonsusceptibility constitute a challenge for patient management and infection control at our medical center.

  5. Cloning, Production, and Functional Expression of the Bacteriocin Enterocin A, Produced by Enterococcus faecium T136, by the Yeasts Pichia pastoris, Kluyveromyces lactis, Hansenula polymorpha, and Arxula adeninivorans

    PubMed Central

    Borrero, Juan; Kunze, Gotthard; Jiménez, Juan J.; Böer, Erik; Gútiez, Loreto; Herranz, Carmen; Cintas, Luis M.

    2012-01-01

    The bacteriocin enterocin A (EntA) produced by Enterococcus faecium T136 has been successfully cloned and produced by the yeasts Pichia pastoris X-33EA, Kluyveromyces lactis GG799EA, Hansenula polymorpha KL8-1EA, and Arxula adeninivorans G1212EA. Moreover, P. pastoris X-33EA and K. lactis GG799EA produced EntA in larger amounts and with higher antimicrobial and specific antimicrobial activities than the EntA produced by E. faecium T136. PMID:22685156

  6. Complete Genome Sequences of Isolates of Enterococcus faecium Sequence Type 117, a Globally Disseminated Multidrug-Resistant Clone

    PubMed Central

    Tedim, Ana P.; Lanza, Val F.; Manrique, Marina; Pareja, Eduardo; Ruiz-Garbajosa, Patricia; Cantón, Rafael; Baquero, Fernando; Tobes, Raquel

    2017-01-01

    ABSTRACT The emergence of nosocomial infections by multidrug-resistant sequence type 117 (ST117) Enterococcus faecium has been reported in several European countries. ST117 has been detected in Spanish hospitals as one of the main causes of bloodstream infections. We analyzed genome variations of ST117 strains isolated in Madrid and describe the first ST117 closed genome sequences. PMID:28360174

  7. Cloning of the bile salt hydrolase (bsh) gene from Enterococcus faecium FAIR-E 345 and chromosomal location of bsh genes in food enterococci.

    PubMed

    Wijaya, Agus; Hermann, Anette; Abriouel, Hikmate; Specht, Ingrid; Yousif, Nuha M K; Holzapfel, Wilhelm H; Franz, Charles M A P

    2004-12-01

    Enterococcus faecium strain FAIR-E 345 isolated from food was shown to possess bile salt hydrolase (Bsh) activity in a plate screening assay and by high-performance liquid chromatography analysis. The bsh gene was cloned and sequenced. DNA sequence analysis revealed that it encoded a protein of 324 amino acids, with pI 4.877. A bsh gene probe was prepared from the cloned bsh gene and was used for probing plasmid and total genomic DNA of Bsh-positive enterococci isolated from food to determine the genomic location of their bsh genes. This probe was able to detect the bsh gene among total genomic DNA preparations but not from plasmid preparations of 10 plasmid-bearing Enterococcus strains. However, the probe could detect the bsh gene from total genomic DNA preparations of 12 Enterococcus strains that did not contain detectable plasmid DNA. In no cases did the probe hybridize with plasmid DNA preparations, suggesting that the bsh gene among enterococci is probably generally chromosomally encoded. This presumptive chromosomal location of bsh genes among food enterococci suggests that transfer of this trait by conjugative plasmids is unlikely.

  8. Rapid detection of high-risk Enterococcus faecium clones by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

    PubMed

    Freitas, Ana R; Sousa, Clara; Novais, Carla; Silva, Liliana; Ramos, Helena; Coque, Teresa M; Lopes, João; Peixe, Luísa

    2017-04-01

    We aimed to explore the potential of matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for early identification of dominant Enterococcus faecium (Efm) clones involved in human infections. Well-characterized Efm isolates (n=77), analyzed by pulsed-field gel electrophoresis and multilocus sequence typing(eBURST and BAPS [Bayesian analysis of population structure] algorithms), and belonging to different hospital (n=53) and community (n=24) phylogenomic groups, were tested. Mass spectra (Bruker) were analyzed by visual inspection and different chemometric tools. Discrimination between groups comprising isolates commonly found in hospitals (BAPS 2.1a, 3.3a1, 3.3a2) and community (BAPS 2.1b and 3.2) was achieved with >99% accuracy, while identification of sequence types belonging to different BAPS subgroups was associated with >95% correct predictions. Our work is a proof of concept with regard to the suitability of MALDI-TOF MS in the identification of high-risk Efm clones. Further studies including strains from a wider variety of clones and sources will strengthen the potential of the workflow here described.

  9. Enterococcus faecium small colony variant endocarditis in an immunocompetent patient

    PubMed Central

    Egido, S. Hernández; Ruiz, M. Siller; Inés Revuelta, S.; García, I. García; Bellido, J.L. Muñoz

    2015-01-01

    Small colony variants (SCV) are slow-growing subpopulations of bacteria usually associated with auxotrophism, causing persistent or recurrent infections. Enterococcus faecalis SCV have been seldom described, and only one case of Enterococcus faecium SCV has been reported, associated with sepsis in a leukaemia patient. Here we report the first case described of bacteraemia and endocarditis by SCV E. faecium in an immunocompetent patient. PMID:26862434

  10. Genetic variability of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis isolates from humans, chickens, and pigs in Malaysia.

    PubMed

    Getachew, Yitbarek; Hassan, Latiffah; Zakaria, Zunita; Abdul Aziz, Saleha

    2013-08-01

    Vancomycin-resistant enterococci (VRE) have been reported to be present in humans, chickens, and pigs in Malaysia. In the present study, representative samples of VRE isolated from these populations were examined for similarities and differences by using the multilocus sequence typing (MLST) method. Housekeeping genes of Enterococcus faecium (n = 14) and Enterococcus faecalis (n = 11) isolates were sequenced and analyzed using the MLST databases eBURST and goeBURST. We found five sequence types (STs) of E. faecium and six STs of E. faecalis existing in Malaysia. Enterococcus faecium isolates belonging to ST203, ST17, ST55, ST79, and ST29 were identified, and E. faecium ST203 was the most common among humans. The MLST profiles of E. faecium from humans in this study were similar to the globally reported nosocomial-related strain lineage belonging to clonal complex 17 (CC17). Isolates from chickens and pigs have few similarities to those from humans, except for one isolate from a chicken, which was identified as ST203. E. faecalis isolates were more diverse and were identified as ST4, ST6, ST87, ST108, ST274, and ST244, which were grouped as specific to the three hosts. E. faecalis, belonging to the high-risk CC2 and CC87, were detected among isolates from humans. In conclusion, even though one isolate from a chicken was found clonal to that of humans, the MLST analysis of E. faecium and E. faecalis supports the findings of others who suggest VRE to be predominantly host specific and that clinically important strains are found mainly among humans. The infrequent detection of a human VRE clone in a chicken may in fact suggest a reverse transmission of VRE from humans to animals.

  11. Production of Enterocin P, an Antilisterial Pediocin-Like Bacteriocin from Enterococcus faecium P13, in Pichia pastoris

    PubMed Central

    Gutiérrez, Jorge; Criado, Raquel; Martín, María; Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.

    2005-01-01

    The gene encoding mature enterocin P (EntP), an antimicrobial peptide from Enterococcus faecium P13, was cloned into the pPICZαA expression vector to generate plasmid pJC31. This plasmid was integrated into the genome of P. pastoris X-33, and EntP was heterologously secreted from the recombinant P. pastoris X-33t1 derivative at a higher production and antagonistic activity than from E. faecium P13. PMID:15980385

  12. Characterization of Class IIa Bacteriocin Resistance in Enterococcus faecium.

    PubMed

    Geldart, Kathryn; Kaznessis, Yiannis N

    2017-04-01

    Vancomycin-resistant enterococci, particularly resistant Enterococcus faecium, pose an escalating threat in nosocomial environments because of their innate resistance to many antibiotics, including vancomycin, a treatment of last resort. Many class IIa bacteriocins strongly target these enterococci and may offer a potential alternative for the management of this pathogen. However, E. faecium's resistance to these peptides remains relatively uncharacterized. Here, we explored the development of resistance of E. faecium to a cocktail of three class IIa bacteriocins: enterocin A, enterocin P, and hiracin JM79. We started by quantifying the frequency of resistance to these peptides in four clinical isolates of E. faecium We then investigated the levels of resistance of E. faecium 6E6 mutants as well as their fitness in different carbon sources. In order to elucidate the mechanism of resistance of E. faecium to class IIa bacteriocins, we completed whole-genome sequencing of resistant mutants and performed reverse transcription-quantitative PCR (qRT-PCR) of a suspected target mannose phosphotransferase (ManPTS). We then verified this ManPTS's role in bacteriocin susceptibility by showing that expression of the ManPTS in Lactococcus lactis results in susceptibility to the peptide cocktail. Based on the evidence found from these studies, we conclude that, in accord with other studies in E. faecalis and Listeria monocytogenes, resistance to class IIa bacteriocins in E. faecium 6E6 is likely caused by the disruption of a particular ManPTS, which we believe we have identified.

  13. A Multicentre Hospital Outbreak in Sweden Caused by Introduction of a vanB2 Transposon into a Stably Maintained pRUM-Plasmid in an Enterococcus faecium ST192 Clone

    PubMed Central

    Sivertsen, Audun; Billström, Hanna; Melefors, Öjar; Liljequist, Barbro Olsson; Wisell, Karin Tegmark; Ullberg, Måns; Özenci, Volkan; Sundsfjord, Arnfinn; Hegstad, Kristin

    2014-01-01

    The clonal dissemination of VanB-type vancomycin-resistant Enterococcus faecium (VREfm) strains in three Swedish hospitals between 2007 and 2011 prompted further analysis to reveal the possible origin and molecular characteristics of the outbreak strain. A representative subset of VREfm isolates (n = 18) and vancomycin-susceptible E. faecium (VSEfm, n = 2) reflecting the spread in time and location was approached by an array of methods including: selective whole genome sequencing (WGS; n = 3), multi locus sequence typing (MLST), antimicrobial susceptibility testing, virulence gene profiling, identification of mobile genetic elements conferring glycopeptide resistance and their ability to support glycopeptide resistance transfer. In addition, a single VREfm strain with an unrelated PFGE pattern collected prior to the outbreak was examined by WGS. MLST revealed a predominance of ST192, belonging to a hospital adapted high-risk lineage harbouring several known virulence determinants (n≥10). The VREfm outbreak strain was resistant to ampicillin, gentamicin, ciprofloxacin and vancomycin, and susceptible to teicoplanin. Consistently, a vanB2-subtype as part of Tn1549/Tn5382 with a unique genetic signature was identified in the VREfm outbreak strains. Moreover, Southern blot hybridisation analyses of PFGE separated S1 nuclease-restricted total DNAs and filter mating experiments showed that vanB2-Tn1549/Tn5382 was located in a 70-kb sized rep17/pRUM plasmid readily transferable between E. faecium. This plasmid contained an axe-txe toxin-antitoxin module associated with stable maintenance. The two clonally related VSEfm harboured a 40 kb rep17/pRUM plasmid absent of the 30 kb vanB2-Tn1549/Tn5382 gene complex. Otherwise, these two isolates were similar to the VREfm outbreak strain in virulence- and resistance profile. In conclusion, our observations support that the origin of the multicentre outbreak was caused by an introduction of vanB2-Tn1549/Tn5382 into a

  14. Functional genomic analysis of bile salt resistance in Enterococcus faecium

    PubMed Central

    2013-01-01

    Background Enterococcus faecium is a Gram-positive commensal bacterium of the mammalian intestinal tract. In the last two decades it has also emerged as a multi-resistant nosocomial pathogen. In order to survive in and colonize the human intestinal tract E. faecium must resist the deleterious actions of bile. The molecular mechanisms exploited by this bacterium to tolerate bile are as yet unexplored. Results In this study we used a high-throughput quantitative screening approach of transposon mutant library, termed Microarray-based Transposon Mapping (M-TraM), to identify the genetic determinants required for resistance to bile salts in E. faecium E1162. The gene gltK, which is predicted to encode a glutamate/aspartate transport system permease protein, was identified by M-TraM to be involved in bile resistance. The role of GltK in bile salt resistance was confirmed by the subsequent observation that the deletion of gltK significantly sensitized E. faecium E1162 to bile salts. To further characterize the response of E. faecium E1162 to bile salts, we performed a transcriptome analysis to identify genes that are regulated by exposure to 0.02% bile salts. Exposure to bile salts resulted in major transcriptional rearrangements, predominantly in genes involved in carbohydrate, nucleotide and coenzyme transport and metabolism. Conclusion These findings add to a better understanding of the molecular mechanisms by which E. faecium responds and resists the antimicrobial action of bile salts. PMID:23641968

  15. Mature biofilms of Enterococcus faecalis and Enterococcus faecium are highly resistant to antibiotics.

    PubMed

    Holmberg, Anna; Rasmussen, Magnus

    2016-01-01

    Enterococcus faecalis and Enterococcus faecium are important nosocomial pathogens that form biofilms on implanted materials. We compare the antibiotic sensitivity of bacteria in new (established during 24 hours) and mature (established during 120 hours) enterococcal biofilms. Mature biofilms contained more bacteria and were much more tolerant to antibiotics, including rifampicin-containing combinations, as judged by determination of minimal biofilm eradication concentrations and by time-kill experiments of bacteria in biofilms formed on beads of bone cement.

  16. High genetic diversity of Enterococcus faecium and Enterococcus faecalis clinical isolates by pulsed-field gel electrophoresis and multilocus sequence typing from a hospital in Malaysia.

    PubMed

    Weng, Poh Leng; Ramli, Ramliza; Shamsudin, Mariana Nor; Cheah, Yoke-Kqueen; Hamat, Rukman Awang

    2013-01-01

    Little is known on the genetic relatedness and potential dissemination of particular enterococcal clones in Malaysia. We studied the antibiotic susceptibility profiles of Enterococcus faecium and Enterococcus faecalis and subjected them to pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). E. faecium and E. faecalis displayed 27 and 30 pulsotypes, respectively, and 10 representative E. faecium and E. faecalis isolates (five each) yielded few different sequence types (STs): ST17 (2 isolates), ST78, ST203, and ST601 for E. faecium, and ST6, ST16, ST28, ST179, and ST399 for E. faecalis. Resistance to tazobactam-piperacillin and ampicillin amongst E. faecium isolates was highly observed as compared to E. faecalis isolates. All of the isolates were sensitive to vancomycin and teicoplanin. The presence of epidemic and nosocomial strains of selected E. faecium STs: 17, 78, and 203 and E. faecalis ST6 as well as high rates of resistance to multiple antibiotics amongst E. faecium isolates is of a particular concern.

  17. New Insights into the Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus Host Interaction Mechanisms

    PubMed Central

    Romero-Hernández, Beatriz; Conde-Moreno, Elisa; Kwak, Young-Keun; Zamora, Javier; Colque-Navarro, Patricia; Möllby, Roland; Ruiz-Garbajosa, Patricia; Cantón, Rafael; García-Bermejo, Laura; del Campo, Rosa

    2016-01-01

    Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) were classically clustered into the Lancefield Group D streptococci and despite their taxonomic reclassification still share a similar genetic content and environment. Both species are considered as opportunistic pathogens. E. faecium is often associated with nosocomial bacteraemia, and S. gallolyticus is sporadically found in endocarditis of colorectal cancer patients. In both cases, the source of infection is commonly endogenous with a translocation process that launches through the intestinal barrier. To get new insights into the pathological processes preceding infection development of both organisms, we used an in vitro model with Caco-2 cells to study and compare the adhesion, invasion and translocation inherent abilities of 6 E. faecium and 4 S. gallolyticus well-characterized isolates. Additionally, biofilm formation on polystyrene, collagen I and IV was also explored. Overall results showed that E. faecium translocated more efficiently than S. gallolyticus, inducing a destabilization of the intestinal monolayer. Isolates Efm106, Efm121 and Efm113 (p < .001 compared to Ef222) exhibited the higher translocation ability and were able to adhere 2–3 times higher than S. gallolyticus isolates. Both species preferred the collagen IV coated surfaces to form biofilm but the S. gallolyticus structures were more compact (p = .01). These results may support a relationship between biofilm formation and vegetation establishment in S. gallolyticus endocarditis, whereas the high translocation ability of E. faecium high-risk clones might partially explain the increasing number of bacteraemia. PMID:27463203

  18. New Insights into the Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus Host Interaction Mechanisms.

    PubMed

    Sánchez-Díaz, Ana María; Romero-Hernández, Beatriz; Conde-Moreno, Elisa; Kwak, Young-Keun; Zamora, Javier; Colque-Navarro, Patricia; Möllby, Roland; Ruiz-Garbajosa, Patricia; Cantón, Rafael; García-Bermejo, Laura; Del Campo, Rosa

    2016-01-01

    Enterococcus faecium and Streptococcus gallolyticus subsp. gallolyticus (S. gallolyticus) were classically clustered into the Lancefield Group D streptococci and despite their taxonomic reclassification still share a similar genetic content and environment. Both species are considered as opportunistic pathogens. E. faecium is often associated with nosocomial bacteraemia, and S. gallolyticus is sporadically found in endocarditis of colorectal cancer patients. In both cases, the source of infection is commonly endogenous with a translocation process that launches through the intestinal barrier. To get new insights into the pathological processes preceding infection development of both organisms, we used an in vitro model with Caco-2 cells to study and compare the adhesion, invasion and translocation inherent abilities of 6 E. faecium and 4 S. gallolyticus well-characterized isolates. Additionally, biofilm formation on polystyrene, collagen I and IV was also explored. Overall results showed that E. faecium translocated more efficiently than S. gallolyticus, inducing a destabilization of the intestinal monolayer. Isolates Efm106, Efm121 and Efm113 (p < .001 compared to Ef222) exhibited the higher translocation ability and were able to adhere 2-3 times higher than S. gallolyticus isolates. Both species preferred the collagen IV coated surfaces to form biofilm but the S. gallolyticus structures were more compact (p = .01). These results may support a relationship between biofilm formation and vegetation establishment in S. gallolyticus endocarditis, whereas the high translocation ability of E. faecium high-risk clones might partially explain the increasing number of bacteraemia.

  19. Presence of virulence factors in Enterococcus faecalis and Enterococcus faecium susceptible and resistant to vancomycin

    PubMed Central

    Comerlato, Carolina Baldisserotto; de Resende, Mariah Costa Carvalho; Caierão, Juliana; d'Azevedo, Pedro Alves

    2013-01-01

    Despite the increasing importance of Enterococcus as opportunistic pathogens, their virulence factors are still poorly understood. This study determines the frequency of virulence factors in clinical and commensal Enterococcus isolates from inpatients in Porto Alegre, Brazil. Fifty Enterococcus isolates were analysed and the presence of the gelE, asa1 and esp genes was determined. Gelatinase activity and biofilm formation were also tested. The clonal relationships among the isolates were evaluated using pulsed-field gel electrophoresis. The asa1, gelE and esp genes were identified in 38%, 60% and 76% of all isolates, respectively. The first two genes were more prevalent in Enterococcus faecalis than in Enterococcus faecium, as was biofilm formation, which was associated with gelE and asa1 genes, but not with the esp gene. The presence of gelE and the activity of gelatinase were not fully concordant. No relationship was observed among any virulence factors and specific subclones of E. faecalis or E. faecium resistant to vancomycin. In conclusion, E. faecalis and E. faecium isolates showed significantly different patterns of virulence determinants. Neither the source of isolation nor the clonal relationship or vancomycin resistance influenced their distribution. PMID:23903974

  20. Co-diversification of Enterococcus faecium Core Genomes and PBP5: Evidences of pbp5 Horizontal Transfer

    PubMed Central

    Novais, Carla; Tedim, Ana P.; Lanza, Val F.; Freitas, Ana R.; Silveira, Eduarda; Escada, Ricardo; Roberts, Adam P.; Al-Haroni, Mohammed; Baquero, Fernando; Peixe, Luísa; Coque, Teresa M.

    2016-01-01

    Ampicillin resistance has greatly contributed to the recent dramatic increase of a cluster of human adapted Enterococcus faecium lineages (ST17, ST18, and ST78) in hospital-based infections. Changes in the chromosomal pbp5 gene have been associated with different levels of ampicillin susceptibility, leading to protein variants (designated as PBP5 C-types to keep the nomenclature used in previous works) with diverse degrees of reduction in penicillin affinity. Our goal was to use a comparative genomics approach to evaluate the relationship between the diversity of PBP5 among E. faecium isolates of different phylogenomic groups as well as to assess the pbp5 transferability among isolates of disparate clonal lineages. The analyses of 78 selected E. faecium strains as well as published E. faecium genomes, suggested that the diversity of pbp5 mirrors the phylogenomic diversification of E. faecium. The presence of identical PBP5 C-types as well as similar pbp5 genetic environments in different E. faecium lineages and clones from quite different geographical and environmental origin was also documented and would indicate their horizontal gene transfer among E. faecium populations. This was supported by experimental assays showing transfer of large (≈180–280 kb) chromosomal genetic platforms containing pbp5 alleles, ponA (transglycosilase) and other metabolic and adaptive features, from E. faecium donor isolates to suitable E. faecium recipient strains. Mutation profile analysis of PBP5 from available genomes and strains from this study suggests that the spread of PBP5 C-types might have occurred even in the absence of a significant ampicillin resistance phenotype. In summary, genetic platforms containing pbp5 sequences were stably maintained in particular E. faecium lineages, but were also able to be transferred among E. faecium clones of different origins, emphasizing the growing risk of further spread of ampicillin resistance in this nosocomial pathogen. PMID

  1. Co-diversification of Enterococcus faecium Core Genomes and PBP5: Evidences of pbp5 Horizontal Transfer.

    PubMed

    Novais, Carla; Tedim, Ana P; Lanza, Val F; Freitas, Ana R; Silveira, Eduarda; Escada, Ricardo; Roberts, Adam P; Al-Haroni, Mohammed; Baquero, Fernando; Peixe, Luísa; Coque, Teresa M

    2016-01-01

    Ampicillin resistance has greatly contributed to the recent dramatic increase of a cluster of human adapted Enterococcus faecium lineages (ST17, ST18, and ST78) in hospital-based infections. Changes in the chromosomal pbp5 gene have been associated with different levels of ampicillin susceptibility, leading to protein variants (designated as PBP5 C-types to keep the nomenclature used in previous works) with diverse degrees of reduction in penicillin affinity. Our goal was to use a comparative genomics approach to evaluate the relationship between the diversity of PBP5 among E. faecium isolates of different phylogenomic groups as well as to assess the pbp5 transferability among isolates of disparate clonal lineages. The analyses of 78 selected E. faecium strains as well as published E. faecium genomes, suggested that the diversity of pbp5 mirrors the phylogenomic diversification of E. faecium. The presence of identical PBP5 C-types as well as similar pbp5 genetic environments in different E. faecium lineages and clones from quite different geographical and environmental origin was also documented and would indicate their horizontal gene transfer among E. faecium populations. This was supported by experimental assays showing transfer of large (≈180-280 kb) chromosomal genetic platforms containing pbp5 alleles, ponA (transglycosilase) and other metabolic and adaptive features, from E. faecium donor isolates to suitable E. faecium recipient strains. Mutation profile analysis of PBP5 from available genomes and strains from this study suggests that the spread of PBP5 C-types might have occurred even in the absence of a significant ampicillin resistance phenotype. In summary, genetic platforms containing pbp5 sequences were stably maintained in particular E. faecium lineages, but were also able to be transferred among E. faecium clones of different origins, emphasizing the growing risk of further spread of ampicillin resistance in this nosocomial pathogen.

  2. Enterococcus faecium isolated from honey synthesized bacteriocin-like substances active against different Listeria monocytogenes strains.

    PubMed

    Ibarguren, Carolina; Raya, Raúl R; Apella, María C; Audisio, M Carina

    2010-02-01

    Four Enterococcus faecium strains, isolated from honeycombs (C1 and M2d strains) and feral combs (Mori1 and M1b strains) secreted antimicrobial substances active against fourteen different Listeria spp. strains. The antimicrobial compound(s) present in the cell free supernatant were highly thermostable (121 degrees C for 15 min) and inactivated by proteolytic enzymes, but not by alpha-amylase and lipase, thus suggesting a peptidic nature. Since the structural bacteriocin gene determinants of enterocins A and B were PCR amplified from the four E. faecium isolates, only the bacteriocin produced by strain C1 was further characterized: it showed a broad band of approximately 4.0-7.0 kDa in SDS-PAGE and was bactericidal (4 log decrease) against L. monocytogenes 99/287. L. monocytogenes 99/287R, a clone spontaneously resistant to the enterocin produced by E. avium DSMZ17511 (ex PA1), was not inhibited by the enterocin-like compounds produced by strain C1. However, it was inhibited in mixed culture fermentations by E. faecium C1 and a bacteriostatic effect was observed. The bacteriocin-producer Enterococcus strains were not haemolytic; gelatinase negative and sensitive to vancomycin and other clinically relevant antibiotics.

  3. Antimicrobial Susceptibility Patterns of Enterococcus faecalis and Enterococcus faecium Isolated from Poultry Flocks in Germany.

    PubMed

    Maasjost, J; Mühldorfer, K; Cortez de Jäckel S; Hafez, H M

    2015-03-01

    Between 2010 and 2011, 145 Enterococcus isolates (Enterococcus faecalis, n = 127; Enterococcus faecium, n = 18) were collected during routine bacteriologic diagnostics from broilers, layers, and fattening turkeys in Germany showing various clinical signs. The susceptibility to 24 antimicrobial agents was investigated by broth microdilution test to determine minimum inhibitory concentrations (MICs). All E. faecalis isolates (n = 127) were susceptible to the beta-lactam antibiotics ampicillin, amoxicillin-clavulanic acid, and penicillin. Corresponding MIC with 50% inhibition (MIC50) and MIC with 90% inhibition (MIC90) values of these antimicrobial agents were at the lower end of the test range (≤ 4 μg/ml). In addition, no vancomycin-resistant enterococci (VRE) were found. High resistance rates were identified in both Enterococcus species for lincomycin (72%-99%) and tetracycline (67%-82%). Half or more than half of Enterococcus isolates were resistant to gentamicin (54%-72%) and the macrolide antibiotics erythromycin (44%-61%) and tylosin-tartate (44%-56%). Enterococcus faecalis isolated from fattening turkeys showed the highest prevalence of antimicrobial resistance compared to other poultry production systems. Eighty-nine out of 145 Enterococcus isolates were resistant to three or more antimicrobial classes. Again, turkeys stood out with 42 (8 1%) multiresistant isolates. The most-frequent resistance patterns of E. faecalis were gentamicin, lincomycin, and tetracycline in all poultry production systems.

  4. Distribution of aminoglycoside resistance genes in recent clinical isolates of Enterococcus faecalis, Enterococcus faecium and Enterococcus avium.

    PubMed Central

    Kobayashi, N.; Alam, M.; Nishimoto, Y.; Urasawa, S.; Uehara, N.; Watanabe, N.

    2001-01-01

    Aminoglycoside modifying enzymes (AMEs) are major factors which confer aminoglycoside resistance on bacteria. Distribution of genes encoding seven AMEs was investigated by multiplex PCR for 279 recent clinical isolates of enterococci derived from a university hospital in Japan. The aac(6')-aph(2"), which is related to high level gentamicin resistance, was detected at higher frequency in Enterococcus faecalis (42.5%) than in Enterococcus faecium (4.3%). Almost half of E. faecalis and E. faecium isolates possessed ant(6)-Ia and aph(3')-IIIa. The profile of AME gene(s) detected most frequently in individual strains of E. faecalis was aac(6')aph(2") + ant(6)-Ia + aph(3')-IIIa, and isolates with this profile showed high level resistance to both gentamicin and streptomycin. In contrast, AME gene profiles of aac(6')-Ii+ ant(6)-Ia+aph(3')-IIIa, followed by aac(6')-Ii alone, were predominant in E. faecium. Only one AME gene profile of ant(6)-Ia+aph(3')-IIIa was found in Enterococcus avium. The ant(4')-Ia and ant(9)-Ia, which have been known to be distributed mostly among Staphylococcus aureus strains, were detected in a few enterococcal strains. An AME gene aph(2")-Ic was not detected in any isolates of the three enterococcal species. These findings indicated a variety of distribution profiles of AME genes among enterococci in our study site. PMID:11349969

  5. Molecular characterization of Rifr mutations in Enterococcus faecalis and Enterococcus faecium.

    PubMed

    Du, Xiaoxing; Hua, Xiaoting; Qu, Tingting; Jiang, Yan; Zhou, Zhihui; Yu, Yunsong

    2014-08-01

    Mutation rate is an important factor affecting the appearance and spread of acquired antibiotic resistance. The frequencies and types of enterococci mutations were determined in this study. The MICs of rifampicin in enterococci and their rifampicin-resistant mutants were determined by the Clinical and Laboratory Standards Institute (CLSI) agar dilution method. The Enterococcus faecalis isolates A15 and 18165 showed no significant differences in mutation frequencies or mutation rates. In Enterococcus faecium, the mutation frequency and mutation rate were both 6·4-fold lower than in E. faecalis. The spectrum of mutations characterized in E. faecium B42 differed significantly from that of E. faecalis. The types and rate of mutations indicated that E. faecalis had a higher potential to develop linezolid resistance. Rifampicin resistance was associated with mutations in the rpoB gene. Rifampicin MICs for the E. faecalis mutant were 2048 mg/l, but rifampicin MICs for E. faecium mutants ranged from 64 to 1024 mg/l.

  6. Modeling the growth of Enterococcus faecium in bologna sausage.

    PubMed Central

    Zanoni, B; Garzaroli, C; Anselmi, S; Rondinini, G

    1993-01-01

    A study to set up mathematical models which allow the prediction of Enterococcus faecium growth in bologna sausage (mortadella) was carried out. Growth curves were obtained at different temperatures (5, 6, 12, 15, 25, 32, 35, 37, 42, 46, 50, 52, and 55 degrees C). The Gompertz and logistic models, modified by Zwietering, were found to fit with the representation of experimental curves. The variations of the parameters A (i.e., the asymptotic value reached by the relative population during the stationary growth phase), mu m (i.e., the maximum specific growth rate during the exponential growth phase), and lambda (i.e., the lag time) with temperature were then modeled. The variation of A with temperature can be described by an empirical polynomial model, whereas the variation of mu m and lambda can be described by the Ratkowsky model modified by Zwietering and the Adair model, respectively. Data processing of these models has shown that the minimum growth temperature for E. faecium is 0.1 degrees C, the maximum growth temperature is 53.4 degrees C, and the optimal growth temperature is 42 to 45 degrees C. PMID:8250562

  7. Influence of enterococcal surface protein (esp) on the transport of Enterococcus faecium within saturated quartz sands.

    PubMed

    Johanson, Jennifer J; Feriancikova, Lucia; Xu, Shangping

    2012-02-07

    Enterococcus was selected by US EPA as a Gram-positive indicator microorganism for groundwater fecal contamination. It was recently reported that enterococcal surface protein (esp) was more prevalent in Enterococcus from human sources than in Enterococcus from nonhuman sources and esp could potentially be used as a source tracking tool for fecal contamination (Scott et al., 2005). In this research, we performed laboratory column transport experiments to investigate the transport of Enterococcus faecium within saturated quartz sands. Particularly, we used a wild type strain (E1162) and a mutant (E1162Δesp) to examine the influence of esp on the transport behavior of E. faecium. Our results showed that esp could significantly enhance the attachment of E. faecium cells onto the surface of silica sands and thus lower the mobility of E. faecium within sand packs. Cell surface properties (e.g., zeta potential) were determined and the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory was applied to explain the effects of esp on the retention of E. faecium. Overall, our results suggested that E. faecium strains with esp could display lower mobility within saturated sand packs than E. faecium strains without esp. The disparity in the transport behavior of E. faecium with and without esp could limit the effectiveness of esp as a source tracking tool within the groundwater system.

  8. Nonclinical and Clinical Enterococcus faecium Strains, but Not Enterococcus faecalis Strains, Have Distinct Structural and Functional Genomic Features

    PubMed Central

    Kim, Eun Bae

    2014-01-01

    Certain strains of Enterococcus faecium and Enterococcus faecalis contribute beneficially to animal health and food production, while others are associated with nosocomial infections. To determine whether there are structural and functional genomic features that are distinct between nonclinical (NC) and clinical (CL) strains of those species, we analyzed the genomes of 31 E. faecium and 38 E. faecalis strains. Hierarchical clustering of 7,017 orthologs found in the E. faecium pangenome revealed that NC strains clustered into two clades and are distinct from CL strains. NC E. faecium genomes are significantly smaller than CL genomes, and this difference was partly explained by significantly fewer mobile genetic elements (ME), virulence factors (VF), and antibiotic resistance (AR) genes. E. faecium ortholog comparisons identified 68 and 153 genes that are enriched for NC and CL strains, respectively. Proximity analysis showed that CL-enriched loci, and not NC-enriched loci, are more frequently colocalized on the genome with ME. In CL genomes, AR genes are also colocalized with ME, and VF are more frequently associated with CL-enriched loci. Genes in 23 functional groups are also differentially enriched between NC and CL E. faecium genomes. In contrast, differences were not observed between NC and CL E. faecalis genomes despite their having larger genomes than E. faecium. Our findings show that unlike E. faecalis, NC and CL E. faecium strains are equipped with distinct structural and functional genomic features indicative of adaptation to different environments. PMID:24141120

  9. Mutant prevention concentrations of daptomycin for Enterococcus faecium clinical isolates.

    PubMed

    Sinel, Clara; Jaussaud, Clara; Auzou, Michel; Giard, Jean-Christophe; Cattoir, Vincent

    2016-10-01

    Owing to the emergence of vancomycin-resistant Enterococcus faecium, treatment of enterococcal infections has become challenging. Although spontaneous in vitro resistance frequencies are low, the emergence of resistance is increasingly reported during daptomycin therapy. The mutant selection window (MSW), comprised between the minimum inhibitory concentration (MIC) and the mutant prevention concentration (MPC), corresponds to the concentration range within which resistant mutants may be selected. Since no data are available for enterococci, the aim of this study was to determine MPCs and MSWs for 12 representative E. faecium clinical isolates. MICs and MPCs were determined by broth microdilution and agar dilution methods, respectively. A basic MSW-derived pharmacodynamic analysis was also performed using mean maximum plasma concentration (Cmax) values obtained with dosages from 4 to 12 mg/kg. MICs and MPCs of daptomycin ranged from 0.5 to 4 mg/L and from 2 to 32 mg/L, respectively, with no correlation between them. The wideness of MSWs ranged from 2× to 32× MIC. Mean plasma Cmax values of daptomycin were calculated from 55 to 174.5 mg/L when using a dosage from 4 to 12 mg/kg. All Cmax values were above the MPCs whatever the dosage. Taking into account the protein binding of daptomycin (ca. 90%), the unbound fraction Cmax was just within the MSW in 67-92% of strains at recommended dosages (4-6 mg/kg) and was above the MPC for the majority of strains only with the highest dosage (12 mg/kg). This study shows that free daptomycin Cmax values usually fell into MSWs when using lower dosages (<10 mg/kg).

  10. Biocide and antibiotic resistance of Enterococcus faecalis and Enterococcus faecium isolated from the swine meat chain.

    PubMed

    Rizzotti, Lucia; Rossi, Franca; Torriani, Sandra

    2016-12-01

    In this study nine strains of Enterococcus faecalis and 12 strains of Enterococcus faecium, isolated from different sample types in the swine meat chain and previously characterized for the presence of antibiotic resistance genes, were examined for phenotypic tolerance to seven biocides (chlorexidine, benzalkonium chloride, triclosan, sodium hypochlorite, 2-propanol, formaldehyde and hydrogen peroxide) and resistance to nine antibiotics (ampicillin, vancomycin, gentamicin, kanamycin, streptomycin, erythromycin, clindamycin, tetracycline and chloramphenicol). Moreover, the presence of efflux system encoding genes qacA/B, qacC, qacE, qacEΔ1, emeA, and stress response genes, sigV and gsp65, involved in the tolerance to biocides, was analysed. Most strains were not tolerant to the biocides, but showed minimum inhibitory concentrations (MICs) higher than the recommended cut-off values for all the antibiotics tested, except for vancomycin and chloramphenicol. Only weak correlations, if any, were found between biocide and antibiotic resistance data. One E. faecalis strain was tolerant to triclosan and one E. faecium strain, with higher tolerance to chlorexidine than the other strains tested, was found to carry a qacA/B gene. Our results indicated that phenotypic resistance to antibiotics is very frequent in enterococcal isolates from the swine meat chain, but phenotypic tolerance to biocides is not common. On the other hand, the gene qacA/B was found for the first time in the species E. faecium, an indication of the necessity to adopt measures suitable to control the spread of biocide resistance determinants among enterococci.

  11. Identification of a novel genomic island specific to hospital-acquired clonal complex 17 Enterococcus faecium isolates.

    PubMed

    Heikens, Esther; van Schaik, Willem; Leavis, Helen L; Bonten, Marc J M; Willems, Rob J L

    2008-11-01

    Hospital-acquired clonal complex 17 (CC17) Enterococcus faecium strains are genetically distinct from indigenous strains and are enriched with resistance genes and virulence genes. We identified a genomic island in CC17 E. faecium tentatively encoding a metabolic pathway involved in carbohydrate transport and metabolism, which may provide a competitive advantage over the indigenous E. faecium microbiota.

  12. Differences in Antibiotic Resistance Patterns of Enterococcus faecalis and Enterococcus faecium Strains Isolated from Farm and Pet Animals

    PubMed Central

    Butaye, Patrick; Devriese, Luc A.; Haesebrouck, Freddy

    2001-01-01

    The prevalence of acquired resistance in 146 Enterococcus faecium and 166 Enterococcus faecalis strains from farm and pet animals, isolated in 1998 and 1999 in Belgium, against antibiotics used for growth promotion and for therapy was determined. Acquired resistance against flavomycin and monensin, two antibiotics used solely for growth promotion, was not detected. Avoparcin (glycopeptide) resistance was found sporadically in E. faecium only. Avilamycin resistance was almost exclusively seen in strains from farm animals. Resistance rates were higher in E. faecium strains from broiler chickens than in strains from other animal groups with tylosin and virginiamycin and in E. faecalis as well as in E. faecium strains with narasin and bacitracin. Resistance against ampicillin was mainly found among E. faecium strains from pets and was absent in E. faecalis. Tetracycline resistance occurred most often in strains from farm animals, while enrofloxacin resistance, only found in E. faecalis, occurred equally among strains from all origins. Resistance against gentamicin was very rare in broiler strains, whereas resistance rates were high in strains from other origins. It can be concluded that resistance against antibiotics used solely for growth promotion was more prevalent in E. faecium strains than in E. faecalis strains. With few exceptions, resistance against the different categories of antibiotics was more prevalent in strains from farm animals than in those from pets. PMID:11302798

  13. Differences in antibiotic resistance patterns of Enterococcus faecalis and Enterococcus faecium strains isolated from farm and pet animals.

    PubMed

    Butaye, P; Devriese, L A; Haesebrouck, F

    2001-05-01

    The prevalence of acquired resistance in 146 Enterococcus faecium and 166 Enterococcus faecalis strains from farm and pet animals, isolated in 1998 and 1999 in Belgium, against antibiotics used for growth promotion and for therapy was determined. Acquired resistance against flavomycin and monensin, two antibiotics used solely for growth promotion, was not detected. Avoparcin (glycopeptide) resistance was found sporadically in E. faecium only. Avilamycin resistance was almost exclusively seen in strains from farm animals. Resistance rates were higher in E. faecium strains from broiler chickens than in strains from other animal groups with tylosin and virginiamycin and in E. faecalis as well as in E. faecium strains with narasin and bacitracin. Resistance against ampicillin was mainly found among E. faecium strains from pets and was absent in E. faecalis. Tetracycline resistance occurred most often in strains from farm animals, while enrofloxacin resistance, only found in E. faecalis, occurred equally among strains from all origins. Resistance against gentamicin was very rare in broiler strains, whereas resistance rates were high in strains from other origins. It can be concluded that resistance against antibiotics used solely for growth promotion was more prevalent in E. faecium strains than in E. faecalis strains. With few exceptions, resistance against the different categories of antibiotics was more prevalent in strains from farm animals than in those from pets.

  14. Linezolid treatment of glycopeptide-resistant Enterococcus faecium in very low birth weight premature neonates.

    PubMed

    Hoehn, Rene; Groll, Andreas H; Schaefer, Volker; Bauer, Karl; Schloesser, Rolf L

    2006-03-01

    Glycopeptide-resistant Enterococcus faecium has emerged as an important nosocomial pathogen with limited therapeutic options. Here we report the successful treatment of glycopeptide-resistant E. faecium infection in two very low birth weight premature infants with the new oxazolidinone linezolid. Treatment with linezolid at a dosage of 10 mg/kg every 8 h intravenously for a duration of 16 days and 14 days, respectively, was well tolerated and led to complete clinical recovery and clearance of the organism from all body sites. The two cases support the clinical efficacy and safety of linezolid in very low birth weight premature neonates with glycopeptide-resistant E. faecium infections.

  15. Dissemination of Enterococcus faecalis and Enterococcus faecium in a ricotta processing plant and evaluation of pathogenic and antibiotic resistance profiles.

    PubMed

    Fernandes, Meg da Silva; Fujimoto, Graciela; de Souza, Leandro Pio; Kabuki, Dirce Yorika; da Silva, Márcio José; Kuaye, Arnaldo Yoshiteru

    2015-04-01

    In this work, the sources of contamination by Enterococcus spp. in a ricotta processing line were evaluated. The isolated strains were tested for virulence genes (gelE, cylA,B, M, esp, agg, ace, efaA, vanB), expression of virulence factors (hemolysin and gelatinase), and the resistance to 10 different antibiotics. Enterococcus faecium and Enterococcus faecalis were subjected to discriminatory identification by intergenic spacer region (ITS)-polymerase chain reaction and sequencing of the ITS region. The results showed that Enterococcus spp. was detected in the raw materials, environment samples and the final product. None of the 107 Enterococcus isolates were completely free from all virulence genes considered. A fraction of 21.5% of the isolates containing all of the genes of the cylA, B, M operon also expressed β-hemolysis. Most of the isolates showed the gelE gene, but only 9.3% were able to hydrolyze gelatin. In addition, 23.5% of the observed Enterococcus isolates had the vanB gene but were susceptible to vancomycin in vitro. The dissemination of antibiotic-resistant enterococci was revealed in this study: 19.3% of the E. faecium samples and 78.0% of the E. faecalis samples were resistant to at least one of the antibiotics tested. Sequencing of region discriminated 5 and 7 distinct groups among E. faecalis and E. faecium, respectively. Although some similarity was observed among some of the isolates, all E. faecalis and E. faecium isolates had genetic differences both in the ITS region and in the virulence profile, which makes them different from each other.

  16. Horizontal transfer of antibiotic resistance from Enterococcus faecium of fermented meat origin to clinical isolates of E. faecium and Enterococcus faecalis.

    PubMed

    Jahan, Musarrat; Zhanel, George G; Sparling, Richard; Holley, Richard A

    2015-04-16

    Enterococcus species are part of the normal intestinal flora of a large number of mammals including humans and consequently, they can be used as indicators of faecal contamination in food and water for human consumption. Their presence in large numbers in foods may indicate a lapse in sanitation and their ability to serve as a genetic reservoir of transferable antibiotic resistance is of concern. In the present study, Enterococcus spp., isolated from commercially fermented meat and human clinical specimen were studied to determine genetic relationships. SmaI pulsed-field gel electrophoresis (PFGE) patterns exhibited genomic heterogeneity within and between both groups of isolates. However, in spite of this heterogeneity there were still substantial phenotypic similarities which suggested that food might be a potential vehicle for distribution of resistant bacteria among humans. In vitro conjugation experiments demonstrated transfer of the tetracycline resistant determinant, tet(M), from Enterococcus faecium S27 isolated from fermented sausage to clinical isolates of both E. faecium and Enterococcus faecalis. The streptomycin resistance of E. faecium S27 was also transferred to a clinical strain, E. faecalis 82916, which was confirmed by the presence of the streptomycin resistance gene, aadA, in the donor and transconjugant strains. Since the aadA gene is associated with a class 1 integron, results also suggested that resistance transfer might have occurred via an integron. It appears this is the first identification of a class 1 integron in E. faecium isolated from food. The importance of food enterococci as a reservoir of antibiotic resistance genes and the potential for their genetic transfer to human strains following consumption of uncooked or undercooked contaminated meat is underlined by this work.

  17. Inhibitory Effect of Enterococcus faecium WB2000 on Volatile Sulfur Compound Production by Porphyromonas gingivalis

    PubMed Central

    Higuchi, Takuya; Nakajima, Masato; Fujimoto, Akie; Hanioka, Takashi; Hirofuji, Takao

    2016-01-01

    Volatile sulfur compounds (VSCs) produced by oral anaerobes are the major compounds responsible for oral malodor. Enterococcus faecium WB2000 is recognized as an antiplaque probiotic bacterium. In this study, the effect of E. faecium WB2000 on VSC production by Porphyromonas gingivalis was evaluated, and the mechanism of inhibition of oral malodor was investigated. P. gingivalis ATCC 33277 was cultured in the presence of four lactic acid bacteria, including E. faecium WB2000. Subsequently, P. gingivalis ATCC 33277, W50, W83, and two clinical isolates were cultured in the presence or absence of E. faecium WB2000, and the emission of VSCs from spent culture medium was measured by gas chromatography. The number of P. gingivalis ATCC 33277 in mixed culture with E. faecium WB2000 decreased at 6 h, and the rate of decrease was higher than that in mixed cultures with the other lactic acid bacteria. The numbers of five P. gingivalis strains decreased at similar rates in mixed culture with E. faecium WB2000. The concentration of methyl mercaptan was lower in spent culture medium from P. gingivalis and E. faecium WB2000 cultures compared with that from P. gingivalis alone. Therefore, E. faecium WB2000 may reduce oral malodor by inhibiting the growth of P. gingivalis and neutralizing methyl mercaptan. PMID:27799940

  18. Antiviral effects of a probiotic Enterococcus faecium strain against transmissible gastroenteritis coronavirus.

    PubMed

    Chai, Weidong; Burwinkel, Michael; Wang, Zhenya; Palissa, Christiane; Esch, Bettina; Twardziok, Sven; Rieger, Juliane; Wrede, Paul; Schmidt, Michael F G

    2013-04-01

    The enteropathogenic coronavirus transmissible gastroenteritis virus (TGEV) causes severe disease in young piglets. We have studied the protective effects of the probiotic Enterococcus faecium NCIMB 10415 (E. faecium), which is approved as a feed additive in the European Union, against TGEV infection. E. faecium was added to swine testicle (ST) cells before, concomitantly with, or after TGEV infection. Viability assays revealed that E. faecium led to a dose-dependent rescue of viability of TGEV-infected cells reaching nearly to complete protection. Virus yields of the E. faecium-treated cultures were reduced by up to three log10 units. Western blot analysis of purified TGEV revealed that the levels of all viral structural proteins were reduced after E. faecium treatment. Using transmission electron microscopy, we observed attachment of TGEV particles to the surface of E. faecium which might be a means to trap virus and to prevent infection. Increased production of nitric oxide in the cells treated with E. faecium and elevated expression of interleukin 6 and 8 pointed to stimulated cellular defense as a mechanism to fight TGEV infection.

  19. Effects of ionophores on Enterococcus faecalis and E. faecium growth in pure and mixed ruminal culture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enterococcus faecalis and faecium are Gram-positive human pathogens that can live in the gastrointestinal tract of food animals. Vancomycin-resistant enterococci (VRE) are an increasing threat to humans as a nosocomial infection, as well as a reservoir of antibiotic resistance genes. Ionophores ar...

  20. Draft Genome Sequence of a Vancomycin-Resistant and Vancomycin-Dependent Enterococcus faecium Isolate

    PubMed Central

    Blaschitz, Marion; Lepuschitz, Sarah; Wagner, Laura; Allerberger, Franz; Indra, Alexander; Huhulescu, Steliana

    2016-01-01

    Vancomycin-resistant enterococci have emerged as major nosocomial pathogens worldwide. While antimicrobial pressure promotes nosocomial colonization with these enterococci, prolonged exposure to vancomycin may foster the transition from vancomycin resistance to vancomycin dependence. Here, we report the draft genome sequence of a vancomycin-dependent Enterococcus faecium isolate showing partial teicoplanin dependence. PMID:27056211

  1. Safety, beneficial and technological properties of Enterococcus faecium isolated from Brazilian cheeses

    PubMed Central

    dos Santos, Karina Maria Olbrich; Vieira, Antônio Diogo Silva; Salles, Hévila Oliveira; Oliveira, Jacqueline da Silva; Rocha, Cíntia Renata Costa; Borges, Maria de Fátima; Bruno, Laura Maria; Franco, Bernadette Dora Gombossy de Melo; Todorov, Svetoslav Dimitrov

    2015-01-01

    This study aimed to characterize the safety and technological properties of Enterococcus faecium strains isolated from Brazilian Coalho cheeses. High levels of co-aggregation were observed between Enterococcus faecium strains EM485 and EM925 and both Escherichia coli and Clostridium perfringens . Both strains presented low levels of hydrophobicity. E. faecium EM485 and EM925 were both able to grow in the presence of 0.5% of the sodium salts of taurocholic acid (TC), taurodeoxycholic acid (TDC), glycocholic acid (GC), and glycodeoxycholic acid (GDC), although they showed the ability to deconjugate only GDC and TDC. Both strains showed good survival when exposed to conditions simulating the gastro intestinal tract (GIT). When tested for the presence of virulence genes, only tyrosine decarboxylase and vancomycin B generated positive PCR results. PMID:26221113

  2. Safety, beneficial and technological properties of Enterococcus faecium isolated from Brazilian cheeses.

    PubMed

    Dos Santos, Karina Maria Olbrich; Vieira, Antônio Diogo Silva; Salles, Hévila Oliveira; Oliveira, Jacqueline da Silva; Rocha, Cíntia Renata Costa; Borges, Maria de Fátima; Bruno, Laura Maria; Franco, Bernadette Dora Gombossy de Melo; Todorov, Svetoslav Dimitrov

    2015-03-01

    This study aimed to characterize the safety and technological properties of Enterococcus faecium strains isolated from Brazilian Coalho cheeses. High levels of co-aggregation were observed between Enterococcus faecium strains EM485 and EM925 and both Escherichia coli and Clostridium perfringens . Both strains presented low levels of hydrophobicity. E. faecium EM485 and EM925 were both able to grow in the presence of 0.5% of the sodium salts of taurocholic acid (TC), taurodeoxycholic acid (TDC), glycocholic acid (GC), and glycodeoxycholic acid (GDC), although they showed the ability to deconjugate only GDC and TDC. Both strains showed good survival when exposed to conditions simulating the gastro intestinal tract (GIT). When tested for the presence of virulence genes, only tyrosine decarboxylase and vancomycin B generated positive PCR results.

  3. Serum cholesterol levels in axenic mice colonized with Enterococcus faecium and Lactobacillus acidophilus.

    PubMed

    Zacconi, C; Bottazzi, V; Rebecchi, A; Bosi, E; Sarra, P G; Tagliaferri, L

    1992-10-01

    Hypocholesterolemic effect was shown in axenic, mono, bicolonized and conventional mice: the effect was different depending on probiotic properties of intestinal microorganisms. Contamination by Enterococcus faecium CX determined the highest effect: haematic cholesterol level decrease was 16.9% in females and 7.8% in males. In mice contaminated by Lactobacillus acidophilus N5 the decrease of haematic cholesterol levels was less and not relevant in mice contaminated by conventional microflora. Enterococcus faecium CX and Lactobacillus acidophilus N5 strains were able to grow in presence of bile salts, to colonize intestinal tract, to survive at gastric conditions and to assimilate cholesterol (E. faecium more than L. acidophilus). The authors consider the possibility to associate probiotic strains with these characteristics for the health of consumers.

  4. Contribution of the enterococcal surface protein Esp to pathogenesis of Enterococcus faecium endocarditis.

    PubMed

    Heikens, Esther; Singh, Kavindra V; Jacques-Palaz, Karen D; van Luit-Asbroek, Miranda; Oostdijk, Evelien A N; Bonten, Marc J M; Murray, Barbara E; Willems, Rob J L

    2011-12-01

    The enterococcal surface protein Esp, specifically linked to nosocomial Enterococcus faecium, is involved in biofilm formation. To assess the role of Esp in endocarditis, a biofilm-associated infection, an Esp-expressing E. faecium strain (E1162) or its Esp-deficient mutant (E1162Δesp) were inoculated through a catheter into the left ventricle of rats. After 24 h, less E1162Δesp than E1162 were recovered from heart valve vegetations. In addition, anti-Esp antibodies were detected in Esp-positive E. faecium bacteremia and endocarditis patient sera. In conclusion, Esp contributes to colonization of E. faecium at the heart valves. Furthermore, systemic infection elicits an Esp-specific antibody response in humans.

  5. Multicenter clinical evaluation of VRESelect agar for identification of vancomycin-resistant Enterococcus faecalis and Enterococcus faecium.

    PubMed

    Anderson, Neil W; Buchan, Blake W; Young, Carol L; Newton, Duane W; Brenke, Connie; Lapsley, Linda; Granato, Paul A; Ledeboer, Nathan A

    2013-08-01

    A chromogenic medium for identification of vancomycin-resistant Enterococcus faecalis and Enterococcus faecium, VRESelect, was compared to bile esculin azide agar with 6 μg/ml vancomycin (BEAV) for the isolation of vancomycin-resistant enterococci (VRE) from stool specimens. At 24 to 28 h, VRESelect demonstrated 98.7% (confidence interval [CI], 96.1 to 99.7%) sensitivity and 99.0% (CI, 98.0 to 99.6%) specificity versus 85.1% (CI, 79.8 to 89.5%) and 90.1% (CI, 79.8 to 89.5%) sensitivity and specificity, respectively, for BEAV.

  6. A new chromogenic agar medium, chromID VRE, to screen for vancomycin-resistant Enterococcus faecium and Enterococcus faecalis.

    PubMed

    Ledeboer, Nathan A; Tibbetts, Robert J; Dunne, William M

    2007-12-01

    We compared the performance of a chromogenic agar medium chromID VRE (bioMérieux, Marcy-l'Etoile, France) designed to recover and identify vancomycin-resistant enterococci (VRE) from clinical specimens with bile esculin azide vancomycin (BEAV) agar. For this study, 120 stool specimens were plated on chromID VRE and BEAV and examined after 24 and 48 h. At 24 h, the sensitivity and specificity were as follows: BEAV, 90.2% and 73%, respectively; chromID VRE, 86.3% and 100.0%, respectively. Furthermore, we determined that the sensitivity and specificity of chromID VRE for Enterococcus faecium were 85.4% and 100%, respectively, and for Enterococcus faecalis, 90% and 100%, respectively. We conclude that chromID VRE provides an equivalent sensitivity for the recovery of VRE from stool specimens, with improved specificity, and the added advantage of providing differentiation between vancomycin-resistant E. faecium and E. faecalis.

  7. Relationship between biofilm formation, the enterococcal surface protein (Esp) and gelatinase in clinical isolates of Enterococcus faecalis and Enterococcus faecium.

    PubMed

    Di Rosa, Roberta; Creti, Roberta; Venditti, Mario; D'Amelio, Raffaele; Arciola, Carla R; Montanaro, Lucio; Baldassarri, Lucilla

    2006-03-01

    One-hundred and twenty-eight enterococcal isolates were examined for their ability to form biofilm in relation to the presence of the gene encoding the enterococcal surface protein (esp), production of gelatinase and to the source of isolation. Neither esp nor gelatinase seemed to be required for biofilm formation: both Enterococcus faecalis and Enterococcus faecium did not show a correlation between the presence of either esp or the production of gelatinase and biofilm formation. However, in E. faecium while esp was found in isolates from either source, the presence of both esp and biofilm together was only found in strains from clinical settings, suggesting that there exists a synergy between these factors which serves as an advantage for the process of infection.

  8. Phenotypic and molecular antibiotic resistance profile of Enterococcus faecalis and Enterococcus faecium isolated from different traditional fermented foods.

    PubMed

    Sánchez Valenzuela, Antonio; Lavilla Lerma, Leyre; Benomar, Nabil; Gálvez, Antonio; Pérez Pulido, Rubén; Abriouel, Hikmate

    2013-02-01

    A collection of 55 enterococci (41 Enterococcus faecium and 14 E. faecalis strains) isolated from various traditional fermented foodstuffs of both animal and vegetable origins, and water was evaluated for resistance against 15 antibiotics. Lower incidence of resistance was observed with gentamicin, ampicillin, penicillin and teicoplanin. However, a high incidence of antibiotic resistance was detected for rifampicin (12 out of 14 of isolates), ciprofloxacin (9/14), and quinupristin/dalfopristin (8/14) in E. faecalis strains. Enterococcus faecium isolates were resistant to rifampicin (25/41), ciprofloxacin (23/41), erythromycin (18/41), levofloxacin (16/41), and nitrofurantoin (15/41). One Enterococcus faecalis and two E. faecium strains were resistant to vancomycin (MIC>16 μg/mL). Among 55 isolates, 27 (19 E. faecium and eight E. faecalis) were resistant to at least three antibiotics. High level of multidrug resistance to clinically important antibiotics was detected in E. faecalis strains (57% of E. faecalis versus 46% of E. faecium), which showed resistance to six to seven antibiotics, especially those isolated from foods of animal origin. So, it is necessary to re-evaluate the use of therapeutic antibiotics in stock farms at both regional and international levels due to the high number of multiple resistant (MR) bacteria. Fifty-six MR E. faecalis and E. faecium strains selected from this and previous studies (Valenzuela et al., 2008, 2010) were screened by polymerase chain reaction for antibiotic resistance genes, revealing the presence of tet(L), tet(M), ermB, cat, efrA, efrB, mphA, or msrA/B genes. The ABC Multidrug Efflux Pump EfrAB was detected in 96% of E. faecalis strains and also in 13% of E. faecium strains; this is the first report describing EfrAB in this enterococcal species. The efflux pump-associated msrA/B gene was detected in 66.66% of E. faecium strains, but not in E. faecalis strains.

  9. Selection of potential probiotic Enterococcus faecium isolated from Portuguese fermented food.

    PubMed

    Barbosa, Joana; Borges, Sandra; Teixeira, Paula

    2014-11-17

    Four Enterococcus faecium strains isolated from fermented products were evaluated for potential use as probiotic strains. In addition to efaAfm gene, commonly found in E. faecium food isolates, none of the isolates possessed virulence genes and none had positive reactions for the production of tyramine, histamine, putrescine and cadaverine in the screening medium used. All of these four isolates proved to be resistant to 65 °C. E. faecium 119 did not show antimicrobial activity against any of the target bacteria investigated. E. faecium 85 and 101 inhibited Listeria innocua and E. faecium DSMZ 13590. The strain E. faecium 120 inhibited seven target bacteria (Listeria monocytogenes 7946, L. monocytogenes 7947, L. innocua 2030c, L. innocua NCTC 11286, E. faecium DSMZ 13590, Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 29213) and was chosen as the representative to assess the ability to survive gastrointestinal tract passage simulation, as well as the protective role of two food matrices (skim milk and Alheira) during its passage. For both matrices used, no significant differences (p<0.05) were obtained between the types of digestion - quick and slow passage simulation. In the skim milk matrix the isolate was reduced to values below the detection limit of the enumeration technique by the end of the two digestions, in contrast to the Alheira matrix, for which isolate 120 showed a reduction of only ca. 1 log CFU/ml. The E. faecium strain 120 was shown to be a potential candidate for further investigations as a potential probiotic culture.

  10. Kinetic analysis of Enterococcus faecium L,D-transpeptidase inactivation by carbapenems.

    PubMed

    Dubée, Vincent; Arthur, Michel; Fief, Hélène; Triboulet, Sébastien; Mainardi, Jean-Luc; Gutmann, Laurent; Sollogoub, Matthieu; Rice, Louis B; Ethève-Quelquejeu, Mélanie; Hugonnet, Jean-Emmanuel

    2012-06-01

    Bypass of classical penicillin-binding proteins by the L,D-transpeptidase of Enterococcus faecium (Ldt(fm)) leads to high-level ampicillin resistance in E. faecium mutants, whereas carbapenems remain the lone highly active β-lactams. Kinetics of Ldt(fm) inactivation was determined for four commercial carbapenems and a derivative obtained by introducing a minimal ethyl group at position 2. We show that the bulky side chains of commercial carbapenems have both positive and negative effects in preventing hydrolysis of the acyl enzyme and impairing drug binding.

  11. Lipoteichoic acid synthesis inhibition in combination with antibiotics abrogates growth of multidrug-resistant Enterococcus faecium.

    PubMed

    Paganelli, Fernanda L; van de Kamer, Tim; Brouwer, Ellen C; Leavis, Helen L; Woodford, Neil; Bonten, Marc J M; Willems, Rob J L; Hendrickx, Antoni P A

    2017-03-01

    Enterococcus faecium is a multidrug-resistant (MDR) nosocomial pathogen causing significant morbidity in debilitated patients. New antimicrobials are needed to treat antibiotic-resistant E. faecium infections in hospitalised patients. E. faecium incorporates lipoteichoic acid (LTA) (1,3-polyglycerol-phosphate linked to glycolipid) in its cell wall. The small-molecule inhibitor 1771 [2-oxo-2-(5-phenyl-1,3,4-oxadiazol-2-ylamino)ethyl 2-naphtho[2,1-b]furan-1-ylacetate] specifically blocks the activity of Staphylococcus aureus LtaS synthase, which polymerises 1,3-glycerolphosphate into LTA polymers. Here we characterised the effects of the small-molecule inhibitor 1771 on the growth of E. faecium isolates, alone (28 strains) or in combination with the antibiotics vancomycin, daptomycin, ampicillin, gentamicin or linezolid (15 strains), and on biofilm formation (16 strains). Inhibition of LTA synthesis at the surface of the cell by compound 1771 in combination with current antibiotic therapy abrogates enterococcal growth in vitro but does not affect mature E. faecium biofilms. Targeting LTA synthesis may provide new possibilities to treat MDR E. faecium infections.

  12. Antibiotic susceptibility, antibacterial activity and characterisation of Enterococcus faecium strains isolated from breast milk

    PubMed Central

    Kıvanç, Sertaç Argun; Kıvanç, Merih; Yiğit, Tülay

    2016-01-01

    Enterococci, which have useful biotechnological applications, produce bacteriocins, including those that exert anti-Listerial activity. The present study aimed to determine the antibiotic susceptibility patterns and antimicrobial activity of Enterococcus faecium strains isolated from human breast milk. The strains were identified using carbohydrate fermentation tests and ribotyping. Subsequently, the antibacterial activity of the isolates was investigated, and the quantities of lactic acid and hydrogen peroxide produced, and the proteolytic activity of E. faecium, were determined. In addition, biofilm formation by E. faecium strains was assessed. E. faecium strains exhibited antimicrobial activity against food-borne and clinical bacterial isolates. Furthermore, following 24 h incubation, the tested strains exhibited resistance to a pH range of 2.0–9.5 and tolerance of bile acid, lysozyme activity and phenol. Supernatants of the E. faecium TM13, TM15, TM17 and TM18 strains were shown to be effective against Listeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains of E. faecium may be used for the development of novel antibacterial agents. PMID:27602088

  13. Linezolid-resistant clinical isolates of meticillin-resistant coagulase-negative staphylococci and Enterococcus faecium from China.

    PubMed

    Cai, Jia Chang; Hu, Yan Yan; Zhang, Rong; Zhou, Hong Wei; Chen, Gong-Xiang

    2012-11-01

    Seventeen meticillin-resistant coagulase-negative staphylococci (MRCoNS), including ten Staphylococcus capitis, four Staphylococcus cohnii, two Staphylococcus haemolyticus and one Staphylococcus sciuri, and an Enterococcus faecium isolate with various levels of linezolid resistance were isolated from intensive care units in a Chinese hospital. PFGE indicated that the four S. cohnii isolates belonged to a clonal strain, and that nine of the S. capitis isolates were indistinguishable (clone A1) and the other one was closely related (clone A2). A G2576T mutation was identified in domain V of the 23S rRNA gene in the E. faecium isolate. Besides the G2576T mutation, a novel C2104T mutation was detected in the nine clone A1 S. capitis isolates. The cfr gene was detected in all the staphylococci except an S. sciuri isolate, whose 23S rRNA gene contained the G2576T mutation. There was a clonal dissemination of linezolid-resistant MRCoNS in intensive care units of our hospital, and this is the first report, to our knowledge, of linezolid-resistant staphylococci and enterococci in China.

  14. Isolation and characterization of tyramine-producing Enterococcus faecium strains from red wine.

    PubMed

    Capozzi, Vittorio; Ladero, Victor; Beneduce, Luciano; Fernández, María; Alvarez, Miguel A; Benoit, Bach; Laurent, Barnavon; Grieco, Francesco; Spano, Giuseppe

    2011-05-01

    Enterococcus faecium strains were isolated from red wines undergoing malolactic fermentation and identified by comparison of their 16S rDNA gene sequences with those included in the GenEMBL Databases. The tyrosine decarboxylase gene was identified in all the strains analysed by PCR using gene-specific primers and the ability to produce tyramine in a synthetic media was analysed by RP-HPLC. Survival of an E. faecium strain was also evaluated in microvinification assays using two different musts with different ethanol concentrations (10% and 12% (v/v)). Tyramine production was monitored during the vinification trials. Our results suggest that E. faecium strains isolated from wine are able to produce tyramine and tolerate wine conditions following a pre-acidic stress.

  15. Epidemic and nonepidemic multidrug-resistant Enterococcus faecium.

    PubMed

    Leavis, Helen L; Willems, Rob J L; Top, Janetta; Spalburg, Emile; Mascini, Ellen M; Fluit, Ad C; Hoepelman, Andy; de Neeling, Albert J; Bonten, Marc J M

    2003-09-01

    The epidemiology of vancomycin-resistant Entero- coccus faecium (VREF) in Europe is characterized by a large community reservoir. In contrast, nosocomial outbreaks and infections (without a community reservoir) characterize VREF in the United States. Previous studies demonstrated host-specific genogroups and a distinct genetic lineage of VREF associated with hospital outbreaks, characterized by the variant esp-gene and a specific allele-type of the purK housekeeping gene (purK1). We investigated the genetic relatedness of vanA VREF (n=108) and vancomycin-susceptible E. faecium (VSEF) (n=92) from different epidemiologic sources by genotyping, susceptibility testing for ampicillin, sequencing of purK1, and testing for presence of esp. Clusters of VSEF fit well into previously described VREF genogroups, and strong associations were found between VSEF and VREF isolates with resistance to ampicillin, presence of esp, and purK1. Genotypes characterized by presence of esp, purK1, and ampicillin resistance were most frequent among outbreak-associated isolates and almost absent among community surveillance isolates. Vancomycin-resistance was not specifically linked to genogroups. VREF and VSEF from different epidemiologic sources are genetically related; evidence exists for nosocomial selection of a subtype of E. faecium, which has acquired vancomycin-resistance through horizontal transfer.

  16. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese.

    PubMed

    Martino, Gabriela P; Quintana, Ingrid M; Espariz, Martín; Blancato, Victor S; Gallina Nizo, Gabriel; Esteban, Luis; Magni, Christian

    2016-02-04

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production.

  17. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese

    PubMed Central

    Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis

    2016-01-01

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907

  18. First record of vancomycin-resistant Enterococcus faecium in Canadian wildlife.

    PubMed

    Oravcova, Veronika; Janecko, Nicol; Ansorge, Antonin; Masarikova, Martina; Literak, Ivan

    2014-06-01

    In this study, we focused on spreading of vancomycin-resistant enterococci (VRE) to the environment. We studied that weather crows in Canada may be carriers and potentially reservoirs of VRE with vanA gene. We have found one multi-resistant isolate of Enterococcus faecium sequence type (ST) 448 with vanA gene on Prince Edward Island. This study is the first report of VRE in Canadian wildlife.

  19. Biological Activities of Tetrodotoxin-Producing Enterococcus faecium AD1 Isolated from Puffer Fishes.

    PubMed

    Nguyen, Tu Hoang Khue; Nguyen, Huu Ngoc; Nghe, Dat Van; Nguyen, Kim Hoang

    2015-01-01

    Puffer fishes were collected from the central sea in Vietnam from spring to summer season. The eggs were incubated in MRS broth that was used to test the toxicity in mice and isolate the lactic acid bacteria community that could produce tetrodotoxin (TTX). Thin layer chromatography (TLC) and high performance lipid chromatography (HPLC) were used to detect and quantify TTX. As a result, Enterococcus faecium AD1 which was identified by biochemical test and 16S rRNA analysis could produce TTX 0.3 mg/mL when cultured in MRS broth. The bacterium was optimized for TTX production and gave 0.18 mg/mL, 0.07 mg/mL, and 0.15 mg/mL in media prepared from the meat-washing water of freshwater fishes (Pangasius bocourti, Oreochromis sp.) and sea fish (Auxis thazard), respectively, that are also hopeful to answer some poisoning cases related to eating fishes. Enterococcus faecium also showed the wide antimicrobial activities on yeast, Gram-negative and -positive bacteria. Extracted exopolysaccharide (EPS) that reacted with 2,2-diphenyl-1-picrylhydrazyl to give IC50 at 5 mg/mL equaled 11 mg/mL ascorbic acid which could show effects on Hela-6 and Hep G2 using sulforhodamine B test. Enterococcus faecium can be claimed as a promising source in tetrodotoxin and biological compounds.

  20. Biological Activities of Tetrodotoxin-Producing Enterococcus faecium AD1 Isolated from Puffer Fishes

    PubMed Central

    Nguyen, Tu Hoang Khue; Nguyen, Huu Ngoc; Nghe, Dat Van; Nguyen, Kim Hoang

    2015-01-01

    Puffer fishes were collected from the central sea in Vietnam from spring to summer season. The eggs were incubated in MRS broth that was used to test the toxicity in mice and isolate the lactic acid bacteria community that could produce tetrodotoxin (TTX). Thin layer chromatography (TLC) and high performance lipid chromatography (HPLC) were used to detect and quantify TTX. As a result, Enterococcus faecium AD1 which was identified by biochemical test and 16S rRNA analysis could produce TTX 0.3 mg/mL when cultured in MRS broth. The bacterium was optimized for TTX production and gave 0.18 mg/mL, 0.07 mg/mL, and 0.15 mg/mL in media prepared from the meat-washing water of freshwater fishes (Pangasius bocourti, Oreochromis sp.) and sea fish (Auxis thazard), respectively, that are also hopeful to answer some poisoning cases related to eating fishes. Enterococcus faecium also showed the wide antimicrobial activities on yeast, Gram-negative and -positive bacteria. Extracted exopolysaccharide (EPS) that reacted with 2,2-diphenyl-1-picrylhydrazyl to give IC50 at 5 mg/mL equaled 11 mg/mL ascorbic acid which could show effects on Hela-6 and Hep G2 using sulforhodamine B test. Enterococcus faecium can be claimed as a promising source in tetrodotoxin and biological compounds. PMID:26380310

  1. A LacI-family regulator activates maltodextrin metabolism of Enterococcus faecium.

    PubMed

    Zhang, Xinglin; Rogers, Malbert; Bierschenk, Damien; Bonten, Marc J M; Willems, Rob J L; van Schaik, Willem

    2013-01-01

    Enterococcus faecium is a gut commensal of humans and animals. In the intestinal tract, E. faecium will have access to a wide variety of carbohydrates, including maltodextrins and maltose, which are the sugars that result from the enzymatic digestion of starch by host-derived and microbial amylases. In this study, we identified the genetic determinants for maltodextrin utilization of E. faecium E1162. We generated a deletion mutant of the mdxABCD-pulA gene cluster that is homologous to maltodextrin uptake genes in other Gram-positive bacteria, and a deletion mutant of the mdxR gene, which is predicted to encode a LacI family regulator of mdxABCD-pulA. Both mutations impaired growth on maltodextrins but had no effect on the growth on maltose and glucose. Comparative transcriptome analysis showed that eight genes (including mdxABCD-pulA) were expressed at significantly lower levels in the isogenic ΔmdxR mutant strain compared to the parental strain when grown on maltose. Quantitative real-time RT-PCR confirmed the results of transcriptome analysis and showed that the transcription of a putative maltose utilization gene cluster is induced in a semi-defined medium supplemented with maltose but is not regulated by MdxR. Understanding the maltodextrin metabolism of E. faecium could yield novel insights into the underlying mechanisms that contribute to the gut commensal lifestyle of E. faecium.

  2. A LacI-Family Regulator Activates Maltodextrin Metabolism of Enterococcus faecium

    PubMed Central

    Zhang, Xinglin; Rogers, Malbert; Bierschenk, Damien; Bonten, Marc J. M.; Willems, Rob J. L.; van Schaik, Willem

    2013-01-01

    Enterococcus faecium is a gut commensal of humans and animals. In the intestinal tract, E. faecium will have access to a wide variety of carbohydrates, including maltodextrins and maltose, which are the sugars that result from the enzymatic digestion of starch by host-derived and microbial amylases. In this study, we identified the genetic determinants for maltodextrin utilization of E. faecium E1162. We generated a deletion mutant of the mdxABCD-pulA gene cluster that is homologous to maltodextrin uptake genes in other Gram-positive bacteria, and a deletion mutant of the mdxR gene, which is predicted to encode a LacI family regulator of mdxABCD-pulA. Both mutations impaired growth on maltodextrins but had no effect on the growth on maltose and glucose. Comparative transcriptome analysis showed that eight genes (including mdxABCD-pulA) were expressed at significantly lower levels in the isogenic ΔmdxR mutant strain compared to the parental strain when grown on maltose. Quantitative real-time RT-PCR confirmed the results of transcriptome analysis and showed that the transcription of a putative maltose utilization gene cluster is induced in a semi-defined medium supplemented with maltose but is not regulated by MdxR. Understanding the maltodextrin metabolism of E. faecium could yield novel insights into the underlying mechanisms that contribute to the gut commensal lifestyle of E. faecium. PMID:23951303

  3. Antimicrobial activity of Enterococcus Faecium Fair-E 198 against gram-positive pathogens

    PubMed Central

    do Nascimento, Maristela da Silva; Moreno, Izildinha; Kuaye, Arnaldo Yoshiteru

    2010-01-01

    ABSTRACT This study investigated the antimicrobial activity of Enterococcus faecium FAIR-E 198 against Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus. Using the critical-dilution method, the bacteriocin produced by E. faecium FAIR-E 198 inhibited all L. monocytogenes strains evaluated (1,600 to 19,200 AU mL-1). However, none of the B. cereus and S. aureus strains investigated were inhibited. The maximum activity of this bacteriocin (800 AU mL-1) was observed in MRS broth, while the activity in milk was 100 AU mL-1. In the co-cultivation test in milk, B. cereus K1-B041 was reduced to below the detection limit (1.00 log CFU mL-1) after 48 h. E. faecium reduced the initial L. monocytogenes Scott A population by 1 log CFU mL-1 after 3 h at 35°C, However, the pathogen regained growth, reaching 3.68 log CFU mL-1 after 48 h. E. faecium did not influence the growth of S. aureus ATCC 27154 during the 48 h of co-cultivation, Therefore, it can be concluded that the effectiveness of the antimicrobial activity of E. faecium FAIR-E 198 is strictly related to the species and strain of the target microorganism and to the culture medium, PMID:24031466

  4. Global Spread of the hylEfm Colonization-Virulence Gene in Megaplasmids of the Enterococcus faecium CC17 Polyclonal Subcluster▿

    PubMed Central

    Freitas, Ana R.; Tedim, Ana P.; Novais, Carla; Ruiz-Garbajosa, Patricia; Werner, Guido; Laverde-Gomez, Jenny A.; Cantón, Rafael; Peixe, Luísa; Baquero, Fernando; Coque, Teresa M.

    2010-01-01

    Enterococcus faecium has increasingly been reported as a nosocomial pathogen since the early 1990s, presumptively associated with the expansion of a human-associated Enterococcus faecium polyclonal subcluster known as clonal complex 17 (CC17) that has progressively acquired different antibiotic resistance (ampicillin and vancomycin) and virulence (espEfm, hylEfm, and fms) traits. We analyzed the presence and the location of a putative glycoside hydrolase hylEfm gene among E. faecium strains obtained from hospitalized patients (255 patients; outbreak, bacteremic, and/or disseminated isolates from 23 countries and five continents; 1986 to 2009) and from nonclinical origins (isolates obtained from healthy humans [25 isolates], poultry [30], swine [90], and the environment [55]; 1999 to 2007). Clonal relatedness was established by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Plasmid analysis included determination of content and size (S1-PFGE), transferability (filter mating), screening of Rep initiator proteins (PCR), and location of vanA, vanB, ermB, and hylEfm genes (S1/I-CeuI hybridization). Most E. faecium isolates contained large plasmids (>150 kb) and showed variable contents of van, hylEfm, or espEfm. The hylEfm gene was associated with megaplasmids (170 to 375 kb) of worldwide spread (ST16, ST17, and ST18) or locally predominant (ST192, ST203, ST280, and ST412) ampicillin-resistant CC17 clones collected in the five continents since the early 1990s. All but one hylEfm-positive isolate belonged to the CC17 polyclonal subcluster. The presence of hylEfm megaplasmids among CC17 from Europe, Australia, Asia, and Africa since at least the mid-1990s was documented. This study further demonstrates the pandemic expansion of particular CC17 clones before acquisition of vancomycin resistance and putative virulence traits and describes the presence of megaplasmids in most of the contemporary E. faecium isolates with different origins. PMID

  5. Characterization of functional properties of Enterococcus faecium strains isolated from human gut.

    PubMed

    İspirli, Hümeyra; Demirbaş, Fatmanur; Dertli, Enes

    2015-11-01

    The aim of this work was to characterize the functional properties of Enterococcus faecium strains identified after isolation from human faeces. Of these isolates, strain R13 showed the best resistance to low pH, bile salts, and survival in the simulated in vitro digestion assay, and demonstrated an important level of adhesion to hexadecane as a potential probiotic candidate. Analysis of the antibiotic resistance of E. faecium strains indicated that in general these isolates were sensitive to the tested antibiotics and no strain appeared to be resistant to vancomycin. Examination of the virulence determinants for E. faecium strains demonstrated that all strains contained the virulence genes common in gut- and food-originated enterococci, and strain R13 harboured the lowest number of virulence genes. Additionally, no strain contained the genes related to cytolysin metabolism and showed hemolytic activity. The antimicrobial role of E. faecium strains was tested against several pathogens, in which different levels of inhibitory effects were observed, and strain R13 was inhibitory to all tested pathogens. PCR screening of genes encoding enterocin A and B indicated the presence of these genes in E. faecium strains. Preliminary characterization of bacteriocins revealed that their activity was lost after proteolytic enzyme treatments, but no alteration in antimicrobial activity was observed at different pHs (3.5 to 9.5) and after heat treatments. In conclusion, this study revealed the functional characteristics of E. faecium R13 as a gut isolate, and this strain could be developed as a new probiotic after further tests.

  6. Growth condition-dependent Esp expression by Enterococcus faecium affects initial adherence and biofilm formation.

    PubMed

    Van Wamel, Willem J B; Hendrickx, Antoni P A; Bonten, Marc J M; Top, Janetta; Posthuma, George; Willems, Rob J L

    2007-02-01

    A genetic subpopulation of Enterococcus faecium, called clonal complex 17 (CC-17), is strongly associated with hospital outbreaks and invasive infections. Most CC-17 strains contain a putative pathogenicity island encoding the E. faecium variant of enterococcal surface protein (Esp). Western blotting, flow cytometric analyses, and electron microscopy showed that Esp is expressed and exposed on the surface of E. faecium, though Esp expression and surface exposure are highly varied among different strains. Furthermore, Esp expression depends on growth conditions like temperature and anaerobioses. When grown at 37 degrees C, five of six esp-positive E. faecium strains showed significantly increased levels of surface-exposed Esp compared to bacteria grown at 21 degrees C, which was confirmed at the transcriptional level by real-time PCR. In addition, a significant increase in surface-exposed Esp was found in half of these strains when grown at 37 degrees C under anaerobic conditions compared to the level in bacteria grown under aerobic conditions. Finally, amounts of surface-exposed Esp correlated with initial adherence to polystyrene (R(2) = 0.7146) and biofilm formation (R(2) = 0.7535). Polystyrene adherence was competitively inhibited by soluble recombinant N-terminal Esp. This study demonstrates that Esp expression on the surface of E. faecium (i) varies consistently between strains, (ii) is growth condition dependent, and (iii) is quantitatively correlated with initial adherence and biofilm formation. These data indicate that E. faecium senses and responds to changing environmental conditions, which might play a role in the early stages of infection when bacteria transit from oxygen-rich conditions at room temperature to anaerobic conditions at body temperature. In addition, variation of surface exposure may explain the contrasting findings reported on the role of Esp in biofilm formation.

  7. Contribution of the collagen adhesin Acm to pathogenesis of Enterococcus faecium in experimental endocarditis.

    PubMed

    Nallapareddy, Sreedhar R; Singh, Kavindra V; Murray, Barbara E

    2008-09-01

    Enterococcus faecium is a multidrug-resistant opportunist causing difficult-to-treat nosocomial infections, including endocarditis, but there are no reports experimentally demonstrating E. faecium virulence determinants. Our previous studies showed that some clinical E. faecium isolates produce a cell wall-anchored collagen adhesin, Acm, and that an isogenic acm deletion mutant of the endocarditis-derived strain TX0082 lost collagen adherence. In this study, we show with a rat endocarditis model that TX0082 Deltaacm::cat is highly attenuated versus wild-type TX0082, both in established (72 h) vegetations (P < 0.0001) and for valve colonization 1 and 3 hours after infection (P faecium pathogenesis. In contrast, no mortality differences were observed in a mouse peritonitis model. While 5 of 17 endocarditis isolates were Acm nonproducers and failed to adhere to collagen in vitro, all had an intact, highly conserved acm locus. Highly reduced acm mRNA levels (>or=50-fold reduction relative to an Acm producer) were found in three of these five nonadherent isolates, including the sequenced strain TX0016, by quantitative reverse transcription-PCR, indicating that acm transcription is downregulated in vitro in these isolates. However, examination of TX0016 cells obtained directly from infected rat vegetations by flow cytometry showed that Acm was present on 40% of cells grown during infection. Finally, we demonstrated a significant reduction in E. faecium collagen adherence by affinity-purified anti-Acm antibodies from E. faecium endocarditis patient sera, suggesting that Acm may be a potential immunotarget for strategies to control this emerging pathogen.

  8. Molecular Epidemiology of Vancomycin-Resistant Enterococcus faecium: a Prospective, Multicenter Study in South American Hospitals▿

    PubMed Central

    Panesso, Diana; Reyes, Jinnethe; Rincón, Sandra; Díaz, Lorena; Galloway-Peña, Jessica; Zurita, Jeannete; Carrillo, Carlos; Merentes, Altagracia; Guzmán, Manuel; Adachi, Javier A.; Murray, Barbara E.; Arias, Cesar A.

    2010-01-01

    Enterococcus faecium has emerged as an important nosocomial pathogen worldwide, and this trend has been associated with the dissemination of a genetic lineage designated clonal cluster 17 (CC17). Enterococcal isolates were collected prospectively (2006 to 2008) from 32 hospitals in Colombia, Ecuador, Perú, and Venezuela and subjected to antimicrobial susceptibility testing. Genotyping was performed with all vancomycin-resistant E. faecium (VREfm) isolates by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. All VREfm isolates were evaluated for the presence of 16 putative virulence genes (14 fms genes, the esp gene of E. faecium [espEfm], and the hyl gene of E. faecium [hylEfm]) and plasmids carrying the fms20-fms21 (pilA), hylEfm, and vanA genes. Of 723 enterococcal isolates recovered, E. faecalis was the most common (78%). Vancomycin resistance was detected in 6% of the isolates (74% of which were E. faecium). Eleven distinct PFGE types were found among the VREfm isolates, with most belonging to sequence types 412 and 18. The ebpAEfm-ebpBEfm-ebpCEfm (pilB) and fms11-fms19-fms16 clusters were detected in all VREfm isolates from the region, whereas espEfm and hylEfm were detected in 69% and 23% of the isolates, respectively. The fms20-fms21 (pilA) cluster, which encodes a putative pilus-like protein, was found on plasmids from almost all VREfm isolates and was sometimes found to coexist with hylEfm and the vanA gene cluster. The population genetics of VREfm in South America appear to resemble those of such strains in the United States in the early years of the CC17 epidemic. The overwhelming presence of plasmids encoding putative virulence factors and vanA genes suggests that E. faecium from the CC17 genogroup may disseminate in the region in the coming years. PMID:20220167

  9. Enterococcus faecium stimulates human neutrophils via the formyl-peptide receptor 2.

    PubMed

    Bloes, Dominik Alexander; Otto, Michael; Peschel, Andreas; Kretschmer, Dorothee

    2012-01-01

    The human formyl-peptide receptor 2 (FPR2/ALX) senses phenol-soluble modulin (PSM) peptide toxins produced by pathogenic staphylococcal species and plays a crucial role in directing neutrophil influx during staphylococcal infection. However, it has remained unclear if FPR2 responds also to molecules from other bacterial pathogens. Here we analyzed a variety of gram-positive and gram-negative pathogens and found that apart from staphylococci only certain enterococcal strains have the capacity to stimulate FPR2/ALX. Most of the analyzed Enterococcus faecium but only sporadic Enterococcus faecalis strains released FPR2/ALX-stimulating molecules leading to neutrophil calcium ion fluxes, chemotaxis, and complement receptor upregulation. Among ten test strains vancomycin-resistant E. faecium had a significantly higher capacity to stimulate FPR2/ALX than vancomycin-susceptible strains, suggesting an association of strong FPR2/ALX activation with health-care associated strains. The enterococcal FPR2/ALX agonists were found to be peptides or proteins, which appear, however, to be unrelated to staphylococcal PSMs in sequence and physicochemical properties. Enterococci are among the most frequent invasive bacterial pathogens but the basis of enterococcal virulence and immune activation has remained incompletely understood. Our study indicates that previously unrecognized proteinaceous agonists contribute to Enterococcus-host interaction and underscores the importance of FPR2/ALX in host defense against major endogenous bacterial pathogens.

  10. Enterococcus faecium PBP5-S/R, the Missing Link between PBP5-S and PBP5-R

    PubMed Central

    Pietta, Ester; Montealegre, Maria Camila; Roh, Jung Hyeob; Cocconcelli, Pier Sandro

    2014-01-01

    During a study to investigate the evolution of ampicillin resistance in Enterococcus faecium, we observed that a number of E. faecium strains, mainly from the recently described subclade A2, showed PBP5 sequences in between PBP5-S and PBP5-R. These hybrid PBP5-S/R patterns reveal a progression of amino acid changes from the S form to the R form of this protein; however, these changes do not strictly correlate with changes in ampicillin MICs. PMID:25182648

  11. Enterococcus faecium PBP5-S/R, the missing link between PBP5-S and PBP5-R.

    PubMed

    Pietta, Ester; Montealegre, Maria Camila; Roh, Jung Hyeob; Cocconcelli, Pier Sandro; Murray, Barbara E

    2014-11-01

    During a study to investigate the evolution of ampicillin resistance in Enterococcus faecium, we observed that a number of E. faecium strains, mainly from the recently described subclade A2, showed PBP5 sequences in between PBP5-S and PBP5-R. These hybrid PBP5-S/R patterns reveal a progression of amino acid changes from the S form to the R form of this protein; however, these changes do not strictly correlate with changes in ampicillin MICs.

  12. Distinct SagA from Hospital-Associated Clade A1 Enterococcus faecium Strains Contributes to Biofilm Formation

    PubMed Central

    Paganelli, F. L.; de Been, M.; Braat, J. C.; Hoogenboezem, T.; Vink, C.; Bayjanov, J.; Rogers, M. R. C.; Huebner, J.; Bonten, M. J. M.; Willems, R. J. L.

    2015-01-01

    Enterococcus faecium is an important nosocomial pathogen causing biofilm-mediated infections. Elucidation of E. faecium biofilm pathogenesis is pivotal for the development of new strategies to treat these infections. In several bacteria, extracellular DNA (eDNA) and proteins act as matrix components contributing to biofilm development. In this study, we investigated biofilm formation capacity and the roles of eDNA and secreted proteins for 83 E. faecium strains with different phylogenetic origins that clustered in clade A1 and clade B. Although there was no significant difference in biofilm formation between E. faecium strains from these two clades, the addition of DNase I or proteinase K to biofilms demonstrated that eDNA is essential for biofilm formation in most E. faecium strains, whereas proteolysis impacted primarily biofilms of E. faecium clade A1 strains. Secreted antigen A (SagA) was the most abundant protein in biofilms from E. faecium clade A1 and B strains, although its localization differed between the two groups. sagA was present in all sequenced E. faecium strains, with a consistent difference in the repeat region between the clades, which correlated with the susceptibility of biofilms to proteinase K. This indicates an association between the SagA variable repeat profile and the localization and contribution of SagA in E. faecium biofilms. PMID:26209668

  13. Distinct SagA from Hospital-Associated Clade A1 Enterococcus faecium Strains Contributes to Biofilm Formation.

    PubMed

    Paganelli, F L; de Been, M; Braat, J C; Hoogenboezem, T; Vink, C; Bayjanov, J; Rogers, M R C; Huebner, J; Bonten, M J M; Willems, R J L; Leavis, H L

    2015-10-01

    Enterococcus faecium is an important nosocomial pathogen causing biofilm-mediated infections. Elucidation of E. faecium biofilm pathogenesis is pivotal for the development of new strategies to treat these infections. In several bacteria, extracellular DNA (eDNA) and proteins act as matrix components contributing to biofilm development. In this study, we investigated biofilm formation capacity and the roles of eDNA and secreted proteins for 83 E. faecium strains with different phylogenetic origins that clustered in clade A1 and clade B. Although there was no significant difference in biofilm formation between E. faecium strains from these two clades, the addition of DNase I or proteinase K to biofilms demonstrated that eDNA is essential for biofilm formation in most E. faecium strains, whereas proteolysis impacted primarily biofilms of E. faecium clade A1 strains. Secreted antigen A (SagA) was the most abundant protein in biofilms from E. faecium clade A1 and B strains, although its localization differed between the two groups. sagA was present in all sequenced E. faecium strains, with a consistent difference in the repeat region between the clades, which correlated with the susceptibility of biofilms to proteinase K. This indicates an association between the SagA variable repeat profile and the localization and contribution of SagA in E. faecium biofilms.

  14. Evaluation of technological properties of Enterococcus faecium CECT 8849, a strain isolated from human milk, for the dairy industry.

    PubMed

    Cárdenas, Nivia; Arroyo, Rebeca; Calzada, Javier; Peirotén, Ángela; Medina, Margarita; Rodríguez, Juan Miguel; Fernández, Leonides

    2016-09-01

    In this work, a variety of biochemical properties of Enterococcus faecium CECT 8849, which had been isolated from breast milk, were analyzed. Its acidifying capacity and proteolytic activity were low but, in contrast, remarkable peptidase and esterase activities were observed. Ethanol and 3-hydroxy-2-butanone were the most abundant volatile compounds found in experimental model cheese manufactured with E. faecium CECT 8849. This strain inhibited the growth of several Listeria monocytogenes and Listeria innocua strains in vitro. Enterocin A and B structural genes were detected in E. faecium CECT 8849. Model fermented milk and cheeses were manufactured from milk inoculated or not with L. innocua CECT 8848 (2.5-3 log10 colony forming units mL(-1)) using E. faecium CECT 8849 or Lactococcus lactis ESI 153 as starter cultures. Although E. faecium CECT 8849 controlled Listeria growth in both dairy models, it led to lower reduction in Listeria counts when compared with L. lactis ESI 153.

  15. A novel putative enterococcal pathogenicity island linked to the esp virulence gene of Enterococcus faecium and associated with epidemicity.

    PubMed

    Leavis, Helen; Top, Janetta; Shankar, Nathan; Borgen, Katrine; Bonten, Marc; van Embden, Jan; Willems, Rob J L

    2004-02-01

    Enterococcus faecalis harbors a virulence-associated surface protein encoded by the esp gene. This gene has been shown to be part of a 150-kb putative pathogenicity island. A gene similar to esp has recently been found in Enterococcus faecium isolates recovered from hospitalized patients. In the present study we analyzed the polymorphism in the esp gene of E. faecium, and we investigated the association of esp with neighboring chromosomal genes. The esp gene showed considerable sequence heterogeneity in the regions encoding the nonrepeat N- and C-terminal domains of the Esp protein as well as differences in the number of repeats. DNA sequencing of chromosomal regions flanking the esp gene of E. faecium revealed seven open reading frames, representing putative genes implicated in virulence, regulation of transcription, and antibiotic resistance. These flanking regions were invariably associated with the presence or absence of the esp gene in E. faecium, indicating that esp in E. faecium is part of a distinct genetic element. Because of the presence of virulence genes in this gene cluster, the lower G+C content relative to that of the genome, and the presence of esp in E. faecium isolates associated with nosocomial outbreaks and clinically documented infections, we conclude that this genetic element constitutes a putative pathogenicity island, the first one described in E. faecium. Except for the presence of esp and araC, this pathogenicity island is completely different from the esp-containing pathogenicity island previously disclosed in E. faecalis.

  16. Inhibitory influence of Enterococcus faecium on the propagation of swine influenza A virus in vitro.

    PubMed

    Wang, Zhenya; Chai, Weidong; Burwinkel, Michael; Twardziok, Sven; Wrede, Paul; Palissa, Christiane; Esch, Bettina; Schmidt, Michael F G

    2013-01-01

    The control of infectious diseases such as swine influenza viruses (SwIV) plays an important role in food production both from the animal health and from the public health point of view. Probiotic microorganisms and other health improving food supplements have been given increasing attention in recent years, but, no information on the effects of probiotics on swine influenza virus is available. Here we address this question by assessing the inhibitory potential of the probiotic Enterococcus faecium NCIMB 10415 (E. faecium) on the replication of two porcine strains of influenza virus (H1N1 and H3N2 strain) in a continuous porcine macrophage cell line (3D4/21) and in MDBK cells. Cell cultures were treated with E. faecium at the non-toxic concentration of 1×10(6) CFU/ml in growth medium for 60 to 90 min before, during and after SwIV infection. After further incubation of cultures in probiotic-free growth medium, cell viability and virus propagation were determined at 48 h or 96 h post infection. The results obtained reveal an almost complete recovery of viability of SwIV infected cells and an inhibition of virus multiplication by up to four log units in the E. faecium treated cells. In both 3D4/21- and MDBK-cells a 60 min treatment with E. faecium stimulated nitric oxide (NO) release which is in line with published evidence for an antiviral function of NO. Furthermore, E. faecium caused a modified cellular expression of selected mediators of defence in 3D4-cells: while the expression of TNF-α, TLR-3 and IL-6 were decreased in the SwIV-infected and probiotic treated cells, IL-10 was found to be increased. Since we obtained experimental evidence for the direct adsorptive trapping of SwIV through E. faecium, this probiotic microorganism inhibits influenza viruses by at least two mechanisms, direct physical interaction and strengthening of innate defence at the cellular level.

  17. Comparison of Enterococcus faecium and Enterococcus faecalis Strains Isolated from Water and Clinical Samples: Antimicrobial Susceptibility and Genetic Relationships

    PubMed Central

    Castillo-Rojas, Gonzalo; Mazari-Hiríart, Marisa; Ponce de León, Sergio; Amieva-Fernández, Rosa I.; Agis-Juárez, Raúl A.; Huebner, Johannes; López-Vidal, Yolanda

    2013-01-01

    Enterococci are part of the normal intestinal flora in a large number of mammals, and these microbes are currently used as indicators of fecal contamination in water and food for human consumption. These organisms are considered one of the primary causes of nosocomial and environmental infections due to their ability to survive in the environment and to their intrinsic resistance to antimicrobials. The aims of this study were to determine the biochemical patterns and antimicrobial susceptibilities of Enterococcus faecalis and E. faecium isolates from clinical samples and from water (groundwater, water from the Xochimilco wetland, and treated water from the Mexico City Metropolitan Area) and to determine the genetic relationships among these isolates. A total of 121 enterococcus strains were studied; 31 and 90 strains were isolated from clinical samples and water (groundwater, water from the Xochimilco wetland, and water for agricultural irrigation), respectively. Identification to the species level was performed using a multiplex PCR assay, and antimicrobial profiles were obtained using a commercial kit. Twenty-eight strains were analyzed by pulsed-field gel electrophoresis (PFGE). E. faecium strains isolated from water showed an atypical biochemical pattern. The clinical isolates showed higher resistance to antibiotics than those from water. Both the enterococci isolated from humans, and those isolated from water showed high genetic diversity according to the PFGE analysis, although some strains seemed to be closely related. In conclusion, enterococci isolated from humans and water are genetically different. However, water represents a potential route of transmission to the community and a source of antimicrobial resistance genes that may be readily transmitted to other, different bacterial species. PMID:23560050

  18. Outbreak of vancomycin-susceptible Enterococcus faecium containing the wild-type vanA gene.

    PubMed

    Szakacs, Tom A; Kalan, Lindsay; McConnell, Michael J; Eshaghi, Alireza; Shahinas, Dea; McGeer, Allison; Wright, Gerry D; Low, Donald E; Patel, Samir N

    2014-05-01

    Accurate detection of vancomycin-resistant enterococci (VRE) is essential in preventing transmission in health care settings. Chromogenic media are widely used for screening VRE because of fast turnaround times (TAT) and high sensitivity. We report an outbreak of Enterococcus faecium bearing vanA yet susceptible to vancomycin (vancomycin-variable Enterococcus [VVE]). Between October 2009 to March 2011, clinical and screening specimens (n=14,747) were screened for VRE using VRE-selective medium and/or PCR. VVE isolates were genotyped to determine relatedness. Plasmids from these isolates were characterized by sequencing. Overall, 52 VVE isolates were identified, comprising 15% of all VRE isolates identified. Isolates demonstrated growth on Brilliance VRE agar (Oxoid) at 24 h of incubation but did not grow on brain heart infusion agar with 6 μg/ml vancomycin (Oxoid) or bile esculin azide agar with 6 μg/ml vancomycin (Oxoid) and were susceptible to vancomycin. Genotyping of 20 randomly selected VVE isolates revealed that 15/20 were identical, while 5 were highly related. PCR of the VVE transposon confirmed the presence of vanHAXY gene cluster; however, vanS (sensor) and vanR (regulator) genes were absent. The outbreak was controlled through routine infection control measures. We report an emergence of a fit strain of E. faecium containing vanA yet susceptible to vancomycin. Whether this new strain represents VRE has yet to be determined; however, unique testing procedures are required for reliable identification of VVE.

  19. A conserved hydrolase responsible for the cleavage of aminoacylphosphatidylglycerol in the membrane of Enterococcus faecium.

    PubMed

    Smith, Angela M; Harrison, Jesse S; Sprague, Kevin M; Roy, Hervé

    2013-08-02

    Aminoacylphosphatidylglycerol synthases (aaPGSs) are enzymes that transfer amino acids from aminoacyl-tRNAs (aa-tRNAs) to phosphatidylglycerol (PG) to form aa-PG in the cytoplasmic membrane of bacteria. aa-PGs provide bacteria with resistance to a range of antimicrobial compounds and stress conditions. Enterococcus faecium encodes a triple-specific aaPGS (RakPGS) that utilizes arginine, alanine, and lysine as substrates. Here we identify a novel hydrolase (AhyD), encoded immediately adjacent to rakPGS in E. faecium, which is responsible for the hydrolysis of aa-PG. The genetic synteny of aaPGS and ahyD is conserved in >60 different bacterial species. Deletion of ahyD in E. faecium resulted in increased formation of Ala-PG and Lys-PG and increased sensitivity to bacitracin. Our results suggest that AhyD and RakPGS act together to maintain optimal levels of aa-PG in the bacterial membrane to confer resistance to certain antimicrobial compounds and stress conditions.

  20. Duplex real-time PCR assay for rapid detection of ampicillin-resistant Enterococcus faecium.

    PubMed

    Mohn, Stein Christian; Ulvik, Arve; Jureen, Roland; Willems, Rob J L; Top, Janetta; Leavis, Helen; Harthug, Stig; Langeland, Nina

    2004-02-01

    Rapid and accurate identification of carriers of resistant microorganisms is an important aspect of efficient infection control in hospitals. Traditional identification methods of antibiotic-resistant bacteria usually take at least 3 to 4 days after sampling. A duplex real-time PCR assay was developed for rapid detection of ampicillin-resistant Enterococcus faecium (ARE). Primers and probes that are used in this assay specifically detected the D-Ala-D-Ala ligase gene of E. faecium and the modified penicillin-binding protein 5 gene (pbp5) carrying the Glu-to-Val substitution at position 629 (Val-629) in a set of 129 tested E. faecium strains with known pbp5 sequence. Presence of the Val-629 in the strain set from 11 different countries was highly correlated with ampicillin resistance. In a screening of hospitalized patients, the real-time PCR assay yielded a sensitivity and a specificity for the detection of ARE colonization of 95% and 100%, respectively. The results were obtained 4 h after samples were harvested from overnight broth of rectal swab samples, identifying both species and the resistance marker mutation in pbp5. This novel assay reliably identifies ARE 2 to 3 days more quickly than traditional culture methods, thereby increasing laboratory throughput, making it useful for rectal screening of ARE. The assay demonstrates the advantages of real-time PCR for detection of nosocomial pathogens.

  1. Enterococcal surface protein Esp is important for biofilm formation of Enterococcus faecium E1162.

    PubMed

    Heikens, Esther; Bonten, Marc J M; Willems, Rob J L

    2007-11-01

    Enterococci have emerged as important nosocomial pathogens with resistance to multiple antibiotics. Adhesion to abiotic materials and biofilm formation on medical devices are considered important virulence properties. A single clonal lineage of Enterococcus faecium, complex 17 (CC17), appears to be a successful nosocomial pathogen, and most CC17 isolates harbor the enterococcal surface protein gene, esp. In this study, we constructed an esp insertion-deletion mutant in a clinical E. faecium CC17 isolate. In addition, initial adherence and biofilm assays were performed. Compared to the wild-type strain, the esp insertion-deletion mutant no longer produced Esp on the cell surface and had significantly lower initial adherence to polystyrene and significantly less biofilm formation, resulting in levels of biofilm comparable to those of an esp-negative isolate. Capacities for initial adherence and biofilm formation were restored in the insertion-deletion mutant by in trans complementation with esp. These results identify Esp as the first documented determinant in E. faecium CC17 with an important role in biofilm formation, which is an essential factor in infection pathogenesis.

  2. Characterization of the effects of Enterococcus faecium on intestinal epithelial transport properties in piglets.

    PubMed

    Klingspor, S; Martens, H; Caushi, D; Twardziok, S; Aschenbach, J R; Lodemann, U

    2013-04-01

    Probiotics have been shown to have positive effects on growth performance traits and the health of farm animals. The objective of the study was to examine whether the probiotic strain Enterococcus faecium NCIMB 10415 (E. faecium) changes the absorptive and secretory transport and barrier properties of piglet jejunum in vitro and thereby to verify tendencies observed in a former feeding trial with E. faecium. Further aims were to assess a potential mechanism of probiotics by testing effects of IL-α, which is upregulated in the peripheral blood mononuclear cells of E. faecium-supplemented piglets, and to test the hypothesis that IL-1α induces a change in ion transport. Sows and their piglets were randomly assigned to a control group and a probiotic group supplemented with E. faecium. The sows received the probiotic supplemented feed from d 28 before parturition and the piglets from d 12 after birth. Piglets were killed at the age of 12 ± 1, 26 ± 1, 34 ± 1, and 54 ± 1 d. Ussing chamber studies were conducted with isolated mucosae from the mid jejunum. Samples were taken for mRNA expression analysis of sodium-glucose-linked transporter 1 (SGLT1) and cystic fibrosis transmembrane conductance regulator (CFTR). The Na(+)/glucose cotransport was increased in the probiotic group compared with the control group at 26 (P = 0.04) and 54 d of age (P = 0.01). The PGE2-induced short circuit current (Isc) was greater at 54 d of age in the probiotic group compared with the control group (P = 0.03). In addition, effects of age on the absorptive (P < 0.01) and secretory (P < 0.01) capacities were observed. Neither SGLT1 nor CFTR mRNA expression was changed by probiotic supplementation. Mannitol flux rates as a marker of paracellular permeability decreased in both groups with increasing age and were less in the probiotic group at the 26 d of age (P = 0.04), indicating a tighter intestinal barrier. The ΔIsc induced by IL-1α was inhibited by bumetanide (P < 0.01), indicating an

  3. Draft Genome Sequence of Enterococcus faecium Strain 58m, Isolated from Intestinal Tract Content of a Woolly Mammoth, Mammuthus primigenius.

    PubMed

    Goncharov, Artemiy; Grigorjev, Semyon; Karaseva, Alena; Kolodzhieva, Viktoria; Azarov, Daniil; Akhremenko, Yana; Tarasova, Lidia; Tikhonov, Alexei; Masharskiy, Alexey; Zueva, Lyudmila; Suvorov, Alexander

    2016-02-11

    Enterococcus faecium 58m is a putative ancient nonpathogenic strain isolated from the intestinal content of an adult woolly mammoth (Mammuthus primigenius). Here, we report its draft genome sequence, consisting of 60 contigs. In silico genomic analysis was performed to determine the genetic features and pathogenic potential of this microorganism.

  4. Draft Genome Sequence of Enterococcus faecium Strain 58m, Isolated from Intestinal Tract Content of a Woolly Mammoth, Mammuthus primigenius

    PubMed Central

    Goncharov, Artemiy; Grigorjev, Semyon; Kolodzhieva, Viktoria; Azarov, Daniil; Akhremenko, Yana; Tarasova, Lidia; Tikhonov, Alexei; Masharskiy, Alexey; Zueva, Lyudmila; Suvorov, Alexander

    2016-01-01

    Enterococcus faecium 58m is a putative ancient nonpathogenic strain isolated from the intestinal content of an adult woolly mammoth (Mammuthus primigenius). Here, we report its draft genome sequence, consisting of 60 contigs. In silico genomic analysis was performed to determine the genetic features and pathogenic potential of this microorganism. PMID:26868396

  5. Antibiotic and disinfectant susceptibility profiles of vancomycin-resistant Enterococcus faecium (VRE) isolated from community wastewater in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vancomycin-resistant Enterococcus faecium (VRE) previously isolated from human wastewater effluents in a nonclinical semiclosed agri-food system in Texas were characterized for susceptibility to antibiotics and disinfectants. The 50 VRE were resistant to eight fluoroquinolones and to 10 of 17 Natio...

  6. Feeding the probiotic Enterococcus faecium strain NCIMB 10415 to piglets specifically reduces the number of Escherichia coli pathotypes that adhere to the gut mucosa.

    PubMed

    Bednorz, Carmen; Guenther, Sebastian; Oelgeschläger, Kathrin; Kinnemann, Bianca; Pieper, Robert; Hartmann, Susanne; Tedin, Karsten; Semmler, Torsten; Neumann, Konrad; Schierack, Peter; Bethe, Astrid; Wieler, Lothar H

    2013-12-01

    Feed supplementation with the probiotic Enterococcus faecium for piglets has been found to reduce pathogenic gut microorganisms. Since Escherichia coli is among the most important pathogens in pig production, we performed comprehensive analyses to gain further insight into the influence of E. faecium NCIMB 10415 on porcine intestinal E. coli. A total of 1,436 E. coli strains were isolated from three intestinal habitats (mucosa, digesta, and feces) of probiotic-supplemented and nonsupplemented (control) piglets. E. coli bacteria were characterized via pulsed-field gel electrophoresis (PFGE) for clonal analysis. The high diversity of E. coli was reflected by 168 clones. Multilocus sequence typing (MLST) was used to determine the phylogenetic backgrounds, revealing 79 sequence types (STs). Pathotypes of E. coli were further defined using multiplex PCR for virulence-associated genes. While these analyses discerned only a few significant differences in the E. coli population between the feeding groups, analyses distinguishing clones that were uniquely isolated in either the probiotic group only, the control group only, or both groups (shared group) revealed clear effects at the habitat level. Interestingly, extraintestinal pathogenic E. coli (ExPEC)-typical clones adhering to the mucosa were significantly reduced in the probiotic group. Our data show a minor influence of E. faecium on the overall population of E. coli in healthy piglets. In contrast, this probiotic has a profound effect on mucosa-adherent E. coli. This finding further substantiates a specific effect of E. faecium strain NCIMB 10415 in piglets against pathogenic E. coli in the intestine. In addition, these data question the relevance of data based on sampling fecal E. coli only.

  7. Feeding the Probiotic Enterococcus faecium Strain NCIMB 10415 to Piglets Specifically Reduces the Number of Escherichia coli Pathotypes That Adhere to the Gut Mucosa

    PubMed Central

    Guenther, Sebastian; Oelgeschläger, Kathrin; Kinnemann, Bianca; Pieper, Robert; Hartmann, Susanne; Tedin, Karsten; Semmler, Torsten; Neumann, Konrad; Schierack, Peter; Bethe, Astrid; Wieler, Lothar H.

    2013-01-01

    Feed supplementation with the probiotic Enterococcus faecium for piglets has been found to reduce pathogenic gut microorganisms. Since Escherichia coli is among the most important pathogens in pig production, we performed comprehensive analyses to gain further insight into the influence of E. faecium NCIMB 10415 on porcine intestinal E. coli. A total of 1,436 E. coli strains were isolated from three intestinal habitats (mucosa, digesta, and feces) of probiotic-supplemented and nonsupplemented (control) piglets. E. coli bacteria were characterized via pulsed-field gel electrophoresis (PFGE) for clonal analysis. The high diversity of E. coli was reflected by 168 clones. Multilocus sequence typing (MLST) was used to determine the phylogenetic backgrounds, revealing 79 sequence types (STs). Pathotypes of E. coli were further defined using multiplex PCR for virulence-associated genes. While these analyses discerned only a few significant differences in the E. coli population between the feeding groups, analyses distinguishing clones that were uniquely isolated in either the probiotic group only, the control group only, or both groups (shared group) revealed clear effects at the habitat level. Interestingly, extraintestinal pathogenic E. coli (ExPEC)-typical clones adhering to the mucosa were significantly reduced in the probiotic group. Our data show a minor influence of E. faecium on the overall population of E. coli in healthy piglets. In contrast, this probiotic has a profound effect on mucosa-adherent E. coli. This finding further substantiates a specific effect of E. faecium strain NCIMB 10415 in piglets against pathogenic E. coli in the intestine. In addition, these data question the relevance of data based on sampling fecal E. coli only. PMID:24123741

  8. High-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium causing invasive infection: Twelve-year surveillance in the Minami Ibaraki Area.

    PubMed

    Osuka, Hanako; Nakajima, Jun; Oishi, Tsuyoshi; Funayama, Yasunori; Ebihara, Tsugio; Ishikawa, Hiroichi; Saito, Kazuto; Koganemaru, Hiroshi; Hitomi, Shigemi

    2016-01-01

    We examined prevalence of high-level aminoglycoside resistance (HLAR) in Enterococcus faecalis and Enterococcus faecium causing invasive infection in the Minami Ibaraki Area. Ten strains of both species each, recovered from the blood or the cerebrospinal fluid between 2003 and 2014, were randomly selected every year. High-level resistance to gentamicin (HLR-GM) and streptomycin (HLR-SM) was detected in 34% (41 of 120 strains) and 18% (21) of E. faecalis and 9% (11) and 39% (48) of E. faecium, respectively. In comparisons of the proportions among three four-year periods, HLR-SM among E. faecium was significantly lower in the 2011-2014 period. All strains with HLR-GM were positive for the aac(6')-Ie-aph(2″)-Ia gene. The ant(6')-Ia gene was detected in all with HLR-SM except for one E. faecalis strain. The present study showed that prevalence of HLR-GM among E. faecalis and E. faecium causing invasive infection in this area was nearly equivalent to that described in previous studies in Japan and that proportions of strains with HLAR did not vary during the study period except for that of HLR-SM among E. faecium.

  9. Algorithm for pre-emptive glycopeptide treatment in patients with haematologic malignancies and an Enterococcus faecium bloodstream infection

    PubMed Central

    2013-01-01

    Introduction Nowadays Enterococcus faecium has become one of the most emerging and challenging nosocomial pathogens. The aim of this study was to determine risk factors in haematology patients who are at risk of an Enterococcus faecium bloodstream infection (BSI) and should be considered for pre-emptive glycopeptide treatment. With these identified risk factors a prediction model can be developed for clinical use. Methods Retrospectively clinical and microbiological data in 33 patients with an E. faecium BSI were compared to 66 control patients during a 5-year period at the haematology ward. Multivariate logistic regression was used to explore the independent risk factors and a prediction model was developed to determine the risk of an E. faecium BSI. Results E. faecium BSIs were found to be associated with high mortality rates. Independent risk factors for E. faecium BSI were colonization with E. faecium 30 days prior to blood culture (OR 5.71; CI 1.7-18.7), combination of neutropenia and abdominal focus (4.37; 1.4-13.4), age > 58 years (4.01; 1.3-12.5), hospital stay prior to blood culture > 14 days (3.55; 0.98-12.9) and CRP (C-reactive protein) level >125 mg/L (4.37; 1.1-10.2). Conclusion Using data from this study, risk stratification for the development of an E. faecium BSI in patients with haematological malignancies is possible. Pre-emptive treatment should be considered in those patients who are at high risk. Using a prediction model as designed in this study, antibiotic stewardship in terms of prudent use of glycopeptides can be improved and might be helpful in controlling further spread of VRE (vancomycin resistant enterococci). PMID:24025668

  10. No beneficial effects evident for Enterococcus faecium NCIMB 10415 in weaned pigs infected with Salmonella enterica serovar Typhimurium DT104.

    PubMed

    Kreuzer, Susanne; Janczyk, Pawel; Assmus, Jens; Schmidt, Michael F G; Brockmann, Gudrun A; Nöckler, Karsten

    2012-07-01

    Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n = 16) as a feed additive and untreated controls (n = 16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P = 0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, γδ T cells, and B cells) in the lymph nodes, Peyer's patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs.

  11. No Beneficial Effects Evident for Enterococcus faecium NCIMB 10415 in Weaned Pigs Infected with Salmonella enterica Serovar Typhimurium DT104

    PubMed Central

    Kreuzer, Susanne; Aßmus, Jens; Schmidt, Michael F. G.; Brockmann, Gudrun A.; Nöckler, Karsten

    2012-01-01

    Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n = 16) as a feed additive and untreated controls (n = 16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P = 0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, γδ T cells, and B cells) in the lymph nodes, Peyer's patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs. PMID:22544257

  12. [Detection of vancomycin-resistant Enterococcus faecium: 2 years' experience in a high complexity hospital ].

    PubMed

    Lopreto, C R; Viegas Caetano, J A; Padlog, R; Sorgentini, M; Bardi, C; Silvestri, C

    2002-01-01

    The presence of vancomycin-resistant enterococci (VRE) in our hospital prompted us to apply an appropriate method for assessing its rectal carriage. A screening method with bile-esculin azide agar plus different concentrations of vancomycin was used. The antimicrobial susceptibility study of enterococci isolated from clinical samples was also emphasized. The present study includes the surveillance and detection of VRE in our hospital during two years. A total of 260 samples corresponding to 138 patients were studied, 158 of them resulting positive. All EVR were Van A Enterococcus faecium, with MICs of vancomycin > or = 256 micrograms/ml. The analysis of susceptibility patterns shows variations with chloramphenicol, tetracycline and high level gentamicin concentrations. This method was easily applied because materials could be available in any clinical microbiology laboratory, and in our hands it has demonstrated to be useful for epidemiological surveillance for EVR.

  13. Increased conjugation frequencies in clinical Enterococcus faecium strains harbouring the enterococcal surface protein gene esp.

    PubMed

    Lund, B; Billström, H; Edlund, C

    2006-06-01

    This study compared the in-vitro ability of Enterococcus faecium isolates of different origin to acquire vanA by conjugation in relation to the occurrence of the esp gene. In total, 29 clinical isolates (15/29 esp+), 30 normal intestinal microflora isolates (2/30 esp+) and one probiotic strain (esp-) were studied with a filter-mating assay. Conjugation events were confirmed by PCR and pulsed-field gel electrophoresis. Among the infection-derived isolates, the esp+ isolates had higher conjugation frequencies compared with esp- isolates (p < 0.001), with a median value of 6.4 x 10(-6) transconjugants/donor. The probiotic strain was shown to acquire vanA vancomycin resistance in in-vitro filter mating experiments.

  14. Novel antibiotic regimens against Enterococcus faecium resistant to ampicillin, vancomycin, and gentamicin.

    PubMed Central

    Landman, D; Mobarakai, N K; Quale, J M

    1993-01-01

    Enterococci have emerged as significant nosocomial pathogens. Enterococci with resistance to commonly used antibiotics are appearing more frequently. We encountered at our institution several infections caused by Enterococcus faecium with high-level resistance to ampicillin, vancomycin, and gentamicin. The optimal antibiotic therapy for serious infections with unusually resistant enterococci has not been established. Using time-kill studies, we tested the effectiveness of various antibiotic combinations against 15 isolates of multidrug-resistant enterococci. No antibiotic was consistently effective when used alone. The combination of ampicillin plus ciprofloxacin was bactericidal for the 12 isolates for which the ciprofloxacin MIC was < or = 8 micrograms/ml. The combination of ciprofloxacin plus novobiocin also demonstrated activity against these isolates. No combination was found to be bactericidal for the remaining three isolates, which were highly ciprofloxacin resistant. These antibiotic combinations may be important for the future treatment of serious infections caused by these resistant pathogens. PMID:8239604

  15. Enterococcus faecium isolated from Lombo, a Portuguese traditional meat product: characterisation of antibacterial compounds and factors affecting bacteriocin production.

    PubMed

    Todorov, S D; Favaro, L; Gibbs, P; Vaz-Velho, M

    2012-12-01

    Strain ST211CH, identified as a strain of Enterococcus faecium, isolated from Lombo produced a bacteriocin that inhibited the growth of Enterococcus spp., Listeria spp., Klebsiella spp., Lactobacillus spp., Pseudomonas spp., Staphylococcus spp. and Streptococcus spp. The mode of action of the bacteriocin named as bacteriocin ST211Ch was bactericidal against Enterococcus faecalis ATCC19443. As determined by Tricine-SDS-PAGE, the approximate molecular mass of the bacteriocin was 8.0 kDa. Loss in antimicrobial activity was recorded after treatment with proteolytic enzymes. Maximum activity of bacteriocin ST211Ch was measured in broth cultures of E. faecium strain ST211Ch after 24 h; thereafter, the activity was reduced. Bacteriocin ST211Ch remained active after exposure to various temperatures and pHs, as well as to Triton X-100, Tween-80, Tween-20, sodium dodecyl sulfate, NaCl, urea and EDTA. Effect of media components on production of bacteriocin ST211Ch was also studied. On the basis of PCR reactions targeting different bacteriocin genes, i.e. enterocins, curvacins and sakacins, no evidences for the presence of these genes in the total DNA of E. faecium strain ST211Ch was obtained. The bacterium most probably produced a bacteriocin different from those mentioned above. Based on the antimicrobial spectrum, stability and mode of action of bacteriocin ST211CH, E. faecium strain ST211Ch might be considered as a potential candidate with beneficial properties for use in biopreservation to control food spoilage bacteria.

  16. Prevalence of Virulence Factors and Vancomycin-resistant Genes among Enterococcus faecalis and E. faecium Isolated from Clinical Specimens

    PubMed Central

    NASAJ, Mona; MOUSAVI, Seyed Masoud; HOSSEINI, Seyed Mostafa; ARABESTANI, Mohammad Reza

    2016-01-01

    Background: The aim of this study was to determine the occurrence of virulence determinants and vancomycin-resistant genes among Enterococcus faecalis and E. faecium obtained from various clinical sources. Methods: The study was performed on the 280 enterococcal isolated from clinical specimens in Hamadan hospitals, western Iran in 2012–14. Antibiotic susceptibility testing was performed using disk diffusion and Minimal Inhibitory Concentration (MIC) methods. The presence of vancomycin-resistant genes and virulence genes was investigated using PCR. Results: Totally 280 enterococcal isolates were identified as follows: E. faecalis (62.5%), E. faecium (24%) and Enterococcus spp (13.5%). The results of antibiotic susceptibility testing showed that resistance rates to vancomycin and teicoplanin in E. faecalis and E. faecium isolates were 5% and 73%, respectively. Of Sixty vancomycin-resistant Enterococci strains, fifty-one isolates were identified as E. faecium (VREfm) and nine as E. faecalis (VREfs). Prevalence of esp, hyl, and asa1 genes were determined as 82%, 71.6%, and 100%, respectively in E. faecium strains; and 78%, 56/6%, and 97%, respectively in E. faecalis strains. Conclusion: The increased frequency of VREF, as seen with rapid rise in the number of vanA isolates should be considered in infection control practices. PMID:27648425

  17. The Capability of Tyramine Production and Correlation between Phenotypic and Genetic Characteristics of Enterococcus faecium and Enterococcus faecalis Strains.

    PubMed

    Bargossi, Eleonora; Gardini, Fausto; Gatto, Veronica; Montanari, Chiara; Torriani, Sandra; Tabanelli, Giulia

    2015-01-01

    The aim of this study was to investigate the diversity of tyramine production capability of four Enterococcus strains in buffered systems in relation to their genetic characteristics and environmental conditions. Cells of the strains Enterococcus faecalis EF37 and ATCC 29212, and E. faecium FC12 and FC643 were re-suspended in phosphate/citrate buffers with different pH, NaCl concentration and incubation temperature. At intervals, cell viability and tyramine production were assessed by plate counting and HPLC analysis, respectively. The activity of a purified tyrosine decarboxylase (TDC) was determined under the same conditions, as a reference. Reduced loss in cell viability was observed in all the tested conditions, except for pH 4 after 24 h. The TDC activity was greatly heterogeneous within the enterococci: EF37 and FC12 produced the higher tyramine concentrations, ATCC 29212 showed a reduced decarboxylase activity, while EF643 did not accumulate detectable amounts of tyramine in all the conditions assayed. Among the considerate variables, temperature was the most influencing factor on tyramine accumulation for enterococcal cells. To further correlate the phenotypic and genetic characteristics of the enterococci, the TDC operon region carrying the genes tyrosine decarboxylase (tyrDC), tyrosine/tyramine permease (tyrP), and Na(+)/H(+) antiporter (nhaC-2) was amplified and sequenced. The genetic organization and nucleotide sequence of this operon region were highly conserved in the enterococcal strains of the same species. The heterogeneity in tyramine production found between the two E. faecalis strains could be ascribed to different regulation mechanisms not yet elucidated. On the contrary, a codon stop was identified in the translated tyrDC sequence of E. faecium FC643, supporting its inability to accumulate tyramine in the tested conditions. In addition, the presence of an additional putative tyrosine decarboxylase with different substrate specificity and

  18. The Capability of Tyramine Production and Correlation between Phenotypic and Genetic Characteristics of Enterococcus faecium and Enterococcus faecalis Strains

    PubMed Central

    Bargossi, Eleonora; Gardini, Fausto; Gatto, Veronica; Montanari, Chiara; Torriani, Sandra; Tabanelli, Giulia

    2015-01-01

    The aim of this study was to investigate the diversity of tyramine production capability of four Enterococcus strains in buffered systems in relation to their genetic characteristics and environmental conditions. Cells of the strains Enterococcus faecalis EF37 and ATCC 29212, and E. faecium FC12 and FC643 were re-suspended in phosphate/citrate buffers with different pH, NaCl concentration and incubation temperature. At intervals, cell viability and tyramine production were assessed by plate counting and HPLC analysis, respectively. The activity of a purified tyrosine decarboxylase (TDC) was determined under the same conditions, as a reference. Reduced loss in cell viability was observed in all the tested conditions, except for pH 4 after 24 h. The TDC activity was greatly heterogeneous within the enterococci: EF37 and FC12 produced the higher tyramine concentrations, ATCC 29212 showed a reduced decarboxylase activity, while EF643 did not accumulate detectable amounts of tyramine in all the conditions assayed. Among the considerate variables, temperature was the most influencing factor on tyramine accumulation for enterococcal cells. To further correlate the phenotypic and genetic characteristics of the enterococci, the TDC operon region carrying the genes tyrosine decarboxylase (tyrDC), tyrosine/tyramine permease (tyrP), and Na+/H+ antiporter (nhaC-2) was amplified and sequenced. The genetic organization and nucleotide sequence of this operon region were highly conserved in the enterococcal strains of the same species. The heterogeneity in tyramine production found between the two E. faecalis strains could be ascribed to different regulation mechanisms not yet elucidated. On the contrary, a codon stop was identified in the translated tyrDC sequence of E. faecium FC643, supporting its inability to accumulate tyramine in the tested conditions. In addition, the presence of an additional putative tyrosine decarboxylase with different substrate specificity and genetic

  19. A Vaccine Approach for the Prevention of Infections by Multidrug-resistant Enterococcus faecium*

    PubMed Central

    Kodali, Srinivas; Vinogradov, Evgeny; Lin, Fiona; Khoury, Nancy; Hao, Li; Pavliak, Vilo; Jones, C. Hal; Laverde, Diana; Huebner, Johannes; Jansen, Kathrin U.; Anderson, Annaliesa S.; Donald, Robert G. K.

    2015-01-01

    The incidence of multidrug-resistant Enterococcus faecium hospital infections has been steadily increasing. With the goal of discovering new vaccine antigens, we systematically fractionated and purified four distinct surface carbohydrates from E. faecium endocarditis isolate Tx16, shown previously to be resistant to phagocytosis in the presence of human serum. The two most abundant polysaccharides consist of novel branched heteroglycan repeating units that include signature sugars altruronic acid and legionaminic acid, respectively. A minor high molecular weight polysaccharide component was recognized as the fructose homopolymer levan, and a glucosylated lipoteichoic acid (LTA) was identified in a micellar fraction. The polysaccharides were conjugated to the CRM197 carrier protein, and the resulting glycoconjugates were used to immunize rabbits. Rabbit immune sera were evaluated for their ability to kill Tx16 in opsonophagocytic assays and in a mouse passive protection infection model. Although antibodies raised against levan failed to mediate opsonophagocytic killing, the other glycoconjugates induced effective opsonic antibodies, with the altruronic acid-containing polysaccharide antisera showing the greatest opsonophagocytic assay activity. Antibodies directed against either novel heteroglycan or the LTA reduced bacterial load in mouse liver or kidney tissue. To assess antigen prevalence, we screened a diverse collection of blood isolates (n = 101) with antibodies to the polysaccharides. LTA was detected on the surface of 80% of the strains, and antigens recognized by antibodies to the two major heteroglycans were co-expressed on 63% of these clinical isolates. Collectively, these results represent the first steps toward identifying components of a glycoconjugate vaccine to prevent E. faecium infection. PMID:26109072

  20. A Vaccine Approach for the Prevention of Infections by Multidrug-resistant Enterococcus faecium.

    PubMed

    Kodali, Srinivas; Vinogradov, Evgeny; Lin, Fiona; Khoury, Nancy; Hao, Li; Pavliak, Vilo; Jones, C Hal; Laverde, Diana; Huebner, Johannes; Jansen, Kathrin U; Anderson, Annaliesa S; Donald, Robert G K

    2015-08-07

    The incidence of multidrug-resistant Enterococcus faecium hospital infections has been steadily increasing. With the goal of discovering new vaccine antigens, we systematically fractionated and purified four distinct surface carbohydrates from E. faecium endocarditis isolate Tx16, shown previously to be resistant to phagocytosis in the presence of human serum. The two most abundant polysaccharides consist of novel branched heteroglycan repeating units that include signature sugars altruronic acid and legionaminic acid, respectively. A minor high molecular weight polysaccharide component was recognized as the fructose homopolymer levan, and a glucosylated lipoteichoic acid (LTA) was identified in a micellar fraction. The polysaccharides were conjugated to the CRM197 carrier protein, and the resulting glycoconjugates were used to immunize rabbits. Rabbit immune sera were evaluated for their ability to kill Tx16 in opsonophagocytic assays and in a mouse passive protection infection model. Although antibodies raised against levan failed to mediate opsonophagocytic killing, the other glycoconjugates induced effective opsonic antibodies, with the altruronic acid-containing polysaccharide antisera showing the greatest opsonophagocytic assay activity. Antibodies directed against either novel heteroglycan or the LTA reduced bacterial load in mouse liver or kidney tissue. To assess antigen prevalence, we screened a diverse collection of blood isolates (n = 101) with antibodies to the polysaccharides. LTA was detected on the surface of 80% of the strains, and antigens recognized by antibodies to the two major heteroglycans were co-expressed on 63% of these clinical isolates. Collectively, these results represent the first steps toward identifying components of a glycoconjugate vaccine to prevent E. faecium infection.

  1. Effects of organic acids on thermal inactivation of acid and cold stressed Enterococcus faecium.

    PubMed

    Fernández, Ana; Alvarez-Ordóñez, Avelino; López, Mercedes; Bernardo, Ana

    2009-08-01

    In this study the adaptative response to heat (70 degrees C) of Enterococcus faecium using fresh and refrigerated (at 4 degrees C for up to 1 month) stationary phase cells grown in Brain Heart Infusion (BHI) buffered at pH 7.4 (non-acid-adapted cells) and acidified BHI at pH values of 6.4 and 5.4 with acetic, ascorbic, citric, lactic, malic and hydrochloric acids (acid-adapted cells) was evaluated. In all cases, the survival curves obtained were concave upward. A mathematical model based on the Weibull distribution accurately described the inactivation kinetic. The results indicate that previous adaptation to a low pH increased the bacterial heat resistance, whereas the subsequent cold storage of cells reduced E. faecium thermal tolerance. Fresh acid-adapted cells showed t(2.5)-values (time needed to obtain an inactivation level of 2.5 log10 cycles) ranging from 2.57 to 9.51 min, while non-acid-adapted cells showed t(2.5)-values of 1.92 min. The extent of increased heat tolerance varied with the acid examined, resulting in the following order: citric > or = acetic > malic > or = lactic > hydrochloric > or = ascorbic. In contrast, cold storage progressively decreased E. faecium thermal resistance. The t(2.5) values found at the end of the period studied were about 2-3-fold lower than those corresponding to non-refrigerated cells, although this decrease was more marked (about 5-fold) when cells were grown in buffered BHI and BHI acidified at pH 5.4 with hydrochloric acid. These findings highlight the need for a better understanding of microbial response to various preservation stresses in order to increase the efficiency of thermal processes and to indicate the convenience of counterbalancing the benefits of the hurdle concept.

  2. Discovery of the first inhibitors of bacterial enzyme D-aspartate ligase from Enterococcus faecium (Aslfm).

    PubMed

    Škedelj, Veronika; Perdih, Andrej; Brvar, Matjaž; Kroflič, Ana; Dubbée, Vincent; Savage, Victoria; O'Neill, Alex J; Solmajer, Tom; Bešter-Rogač, Marija; Blanot, Didier; Hugonnet, Jean-Emmanuel; Magnet, Sophie; Arthur, Michel; Mainardi, Jean-Luc; Stojan, Jure; Zega, Anamarija

    2013-09-01

    The D-aspartate ligase of Enterococcus faecium (Aslfm) is an attractive target for the development of narrow-spectrum antibacterial agents that are active against multidrug-resistant E. faecium. Although there is currently little available information regarding the structural characteristics of Aslfm, we exploited the knowledge that this enzyme belongs to the ATP-grasp superfamily to target its ATP binding site. In the first design stage, we synthesized and screened a small library of known ATP-competitive inhibitors of ATP-grasp enzymes. A series of amino-oxazoles derived from bacterial biotin carboxylase inhibitors showed low micromolar activity. The most potent inhibitor compound 12, inhibits Aslfm with a Ki value of 2.9 μM. In the second design stage, a validated ligand-based pharmacophore modeling approach was used, taking the newly available inhibition data of an initial series of compounds into account. Experimental evaluation of the virtual screening hits identified two novel structural types of Aslfm inhibitors with 7-amino-9H-purine (18) and 7-amino-1H-pyrazolo[3,4-d]pyrimidine (30 and 34) scaffolds, and also with Ki values in the low micromolar range. Investigation the inhibitors modes of action confirmed that these compounds are competitive with respect to the ATP molecule. The binding of inhibitors to the target enzyme was also studied using isothermal titration calorimetry (ITC). Compounds 6, 12, 18, 30 and 34 represent the first inhibitors of Aslfm reported to date, and are an important step forward in combating infections due to E. faecium.

  3. Characterization and complete genome sequence analysis of novel bacteriophage IME-EFm1 infecting Enterococcus faecium.

    PubMed

    Wang, Yahui; Wang, Wei; Lv, Yongqiang; Zheng, Wangliang; Mi, Zhiqiang; Pei, Guangqian; An, Xiaoping; Xu, Xiaomeng; Han, Chuanyin; Liu, Jie; Zhou, Changlin; Tong, Yigang

    2014-11-01

    We isolated and characterized a novel virulent bacteriophage, IME-EFm1, specifically infecting multidrug-resistant Enterococcus faecium. IME-EFm1 is morphologically similar to members of the family Siphoviridae. It was found capable of lysing a wide range of our E. faecium collections, including two strains resistant to vancomycin. One-step growth tests revealed the host lysis activity of phage IME-EFm1, with a latent time of 30 min and a large burst size of 116 p.f.u. per cell. These biological characteristics suggested that IME-EFm1 has the potential to be used as a therapeutic agent. The complete genome of IME-EFm1 was 42 597 bp, and was linear, with terminally non-redundant dsDNA and a G+C content of 35.2 mol%. The termini of the phage genome were determined with next-generation sequencing and were further confirmed by nuclease digestion analysis. To our knowledge, this is the first report of a complete genome sequence of a bacteriophage infecting E. faecium. IME-EFm1 exhibited a low similarity to other phages in terms of genome organization and structural protein amino acid sequences. The coding region corresponded to 90.7 % of the genome; 70 putative ORFs were deduced and, of these, 29 could be functionally identified based on their homology to previously characterized proteins. A predicted metallo-β-lactamase gene was detected in the genome sequence. The identification of an antibiotic resistance gene emphasizes the necessity for complete genome sequencing of a phage to ensure it is free of any undesirable genes before use as a therapeutic agent against bacterial pathogens.

  4. Characterization of Vancomycin-Resistant Enterococcus faecium Isolated from Swine in Three Michigan Counties▿ ‖

    PubMed Central

    Donabedian, Susan M.; Perri, Mary Beth; Abdujamilova, Nodira; Gordoncillo, Mary Joy; Naqvi, Amir; Reyes, Katherine C.; Zervos, Marcus J.; Bartlett, Paul

    2010-01-01

    Vancomycin-resistant enterococci are a major cause of nosocomial infections but are rarely found in humans in the community and have not been identified in food animals in the United States. We evaluated a total of 360 fecal specimens from humans and their animals being raised for exhibit at three county fairs in Michigan. Fecal samples from 158 humans, 55 swine, 50 cattle, 25 horses, 57 sheep, 14 goats, and 1 llama were obtained and plated onto Enterococcosel agar containing 16 μg/ml of vancomycin. Vancomycin-resistant Enterococcus faecium (VREF) was isolated from six pigs but not from humans or any animal other than pigs. All six VREF isolates had a MIC to vancomycin of ≥256 μg/ml and contained the vanA gene. Pulsed-field gel electrophoresis (PFGE) patterns of the six VREF isolates were ≥80% similar. Multilocus sequence typing (MLST) revealed sequence type 5 (ST5) (n = 2), ST6 (n = 3), and ST185 (n = 1), which are E. faecium sequence types belonging to clonal complex 5 (CC5). These findings show the dissemination of VREF strains among pigs in three Michigan counties. This is the first report of VRE found in food animals in the United States. PMID:20739498

  5. The anti-Candida activity by Ancillary Proteins of an Enterococcus faecium strain

    PubMed Central

    Roy, Utpal; Chalasani, Ajay G.; Shekh, M. Raeesh

    2015-01-01

    An antimycotic activity toward seven strains of Candida albicans was demonstrated erstwhile by a wild-type Enterococcus faecium isolated from a penguin rookery of the Antarctic region. In the present study the antimicrobial principle was purified by ion exchange and gel permeation chromatography and further was analyzed by LC-ESI-MS/MS. In the purification steps, the dialyzed concentrate and ion exchange fractions inhibited C. albicans MTCC 3958, 183, and SC 5314. However, the gel filtration purified fractions inhibited MTCC 3958 and 183. The data obtained from the LC-ESI-MS/MS indicate that the antimicrobial activity of the anti-Candida protein produced by E. faecium is facilitated by Sag A/Bb for the binding of the indicator organism's cell membrane. Partial N-terminal sequence revealed 12 N-terminal amino acid residues and its analysis shown that it belongs to the LysM motif. The nucleotide sequence of PCR-amplified product could detect 574 nucleotides of the LysM gene responsible for binding to chitin of the cell wall of Candida sp. PMID:26005434

  6. Characterization of vancomycin-resistant Enterococcus faecium isolated from swine in three Michigan counties.

    PubMed

    Donabedian, Susan M; Perri, Mary Beth; Abdujamilova, Nodira; Gordoncillo, Mary Joy; Naqvi, Amir; Reyes, Katherine C; Zervos, Marcus J; Bartlett, Paul

    2010-11-01

    Vancomycin-resistant enterococci are a major cause of nosocomial infections but are rarely found in humans in the community and have not been identified in food animals in the United States. We evaluated a total of 360 fecal specimens from humans and their animals being raised for exhibit at three county fairs in Michigan. Fecal samples from 158 humans, 55 swine, 50 cattle, 25 horses, 57 sheep, 14 goats, and 1 llama were obtained and plated onto Enterococcosel agar containing 16 μg/ml of vancomycin. Vancomycin-resistant Enterococcus faecium (VREF) was isolated from six pigs but not from humans or any animal other than pigs. All six VREF isolates had a MIC to vancomycin of ≥256 μg/ml and contained the vanA gene. Pulsed-field gel electrophoresis (PFGE) patterns of the six VREF isolates were ≥80% similar. Multilocus sequence typing (MLST) revealed sequence type 5 (ST5) (n = 2), ST6 (n = 3), and ST185 (n = 1), which are E. faecium sequence types belonging to clonal complex 5 (CC5). These findings show the dissemination of VREF strains among pigs in three Michigan counties. This is the first report of VRE found in food animals in the United States.

  7. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus).

    PubMed

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T; Cintas, Luis M; Herranz, Carmen; Holo, Helge; Diep, Dzung B; Vederas, John C; Hernández, Pablo E

    2016-03-24

    Enterococcus faeciumM3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvussubsp.fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential.

  8. Draft Genome Sequence of the Bacteriocin-Producing Strain Enterococcus faecium M3K31, Isolated from Griffon Vultures (Gyps fulvus subsp. fulvus)

    PubMed Central

    Arbulu, Sara; Frantzen, Cyril; Lohans, Christopher T.; Cintas, Luis M.; Herranz, Carmen; Holo, Helge; Diep, Dzung B.; Vederas, John C.

    2016-01-01

    Enterococcus faecium M3K31 is a bacteriocinogenic lactic acid bacterium (LAB) isolated from griffon vulture (Gyps fulvus subsp. fulvus) feces. The draft genome sequence of this strain provides genetic data that support its biotechnological potential. PMID:27013035

  9. Inhibition of Enterococcus faecium adherence to collagen by antibodies against high-affinity binding subdomains of Acm.

    PubMed

    Nallapareddy, Sreedhar R; Sillanpää, Jouko; Ganesh, Vannakambadi K; Höök, Magnus; Murray, Barbara E

    2007-06-01

    Strains of Enterococcus faecium express a cell wall-anchored protein, Acm, which mediates adherence to collagen. Here, we (i) identify the minimal and high-affinity binding subsegments of Acm and (ii) show that anti-Acm immunoglobulin Gs (IgGs) purified against these subsegments reduced E. faecium TX2535 strain collagen adherence up to 73 and 50%, respectively, significantly more than the total IgGs against the full-length Acm A domain (28%) (P < 0.0001). Blocking Acm adherence with functional subsegment-specific antibodies raises the possibility of their use as therapeutic or prophylactic agents.

  10. Antibacterial activity of Enterococcus faecium derived from Koopeh cheese against Listeria monocytogenes in probiotic ultra-filtrated cheese

    PubMed Central

    Hassanzadazar, Hassan; Ehsani, Ali; Mardani, Karim

    2014-01-01

    Viability of probiotic bacteria in food during maintenance and time of consuming in food has become a challenge in food hygiene and technology and is important for representing their beneficial health effects. The aim of this study was to determine the survival of probiotic Enterococcus faecium derived from Koopeh cheese added to industrial Iranian ultra-filtrated (UF) cheese and screening for antimicrobial activity of Enterococcus faecium against Listeria monocytogenes during two months of cheese ripening. Physiochemical and standard microbial methods were used for isolation of Enterococcus strains in cheese samples. The initial number of lactic acid bacteria (LAB) as starter culture was 6 Log g-1 in control samples. The counts started to decrease slightly after day seven (p < 0.05) and dropped to 5 Log g-1 at the end of 60 days. The count of LAB in the test groups decreased to 11 Log g-1 on the day 60 of ripening. The number of Enterococcus faecium was 6 Log g-1 on the day 60. The count of Listeria monocytogenes after 60 days of ripening in blank sample decreased 1 Log but in test samples with protective strain decreased 3 Log in 30 days and reached to zero at 45 days. There were not significant (p < 0.05) changes in chemical parameters such as fat, protein and total solid of UF cheese treatment groups. The results showed that Enterococcus faecium of Koopeh cheese was suitable for development of an acceptable probiotic UF cheese and could be adapted to industrial production of UF cheese. PMID:25568714

  11. Application of bacteriocinogenic Enterococcus mundtii CRL35 and Enterococcus faecium ST88Ch in the control of Listeria monocytogenes in fresh Minas cheese.

    PubMed

    Vera Pingitore, Esteban; Todorov, Svetoslav Dimitrov; Sesma, Fernando; Franco, Bernadette Dora Gombossy de Melo

    2012-10-01

    Several strains of Enterococcus spp. are capable of producing bacteriocins with antimicrobial activity against important bacterial pathogens in dairy products. In this study, the bacteriocins produced by two Enterococcus strains (Enterococcus mundtii CRL35 and Enterococcus faecium ST88Ch), isolated from cheeses, were characterized and tested for their capability to control growth of Listeria monocytogenes 426 in experimentally contaminated fresh Minas cheese during refrigerated storage. Both strains were active against a variety of pathogenic and non-pathogenic microorganisms and bacteriocin absorption to various L. monocytogenes, Enterococcus faecalis ATCC 19443 and Lactobacillus sakei ATCC 15521 varied according to the strain and the testing conditions (pH, temperature, presence of salts and surfactants). Growth of L. monocytogenes 426 was inhibited in cheeses containing E. mundtii CRL35 up to 12 days at 8 °C, evidencing a bacteriostatic effect. E. faecium ST88Ch was less effective, as the bacteriostatic affect occurred only after 6 days at 8 °C. In cheeses containing nisin (12.5 mg/kg), less than one log reduction was observed. This research underlines the potential application of E. mundtii CRL35 in the control of L. monocytogenes in Minas cheese.

  12. Human and Swine Hosts Share Vancomycin-Resistant Enterococcus faecium CC17 and CC5 and Enterococcus faecalis CC2 Clonal Clusters Harboring Tn1546 on Indistinguishable Plasmids▿†

    PubMed Central

    Freitas, Ana R.; Coque, Teresa M.; Novais, Carla; Hammerum, Anette M.; Lester, Camilla H.; Zervos, Marcus J.; Donabedian, Susan; Jensen, Lars B.; Francia, Maria Victoria; Baquero, Fernando; Peixe, Luísa

    2011-01-01

    VRE isolates from pigs (n = 29) and healthy persons (n = 12) recovered during wide surveillance studies performed in Portugal, Denmark, Spain, Switzerland, and the United States (1995 to 2008) were compared with outbreak/prevalent VRE clinical strains (n = 190; 23 countries; 1986 to 2009). Thirty clonally related Enterococcus faecium clonal complex 5 (CC5) isolates (17 sequence type 6 [ST6], 6 ST5, 5 ST185, 1 ST147, and 1 ST493) were obtained from feces of swine and healthy humans. This collection included isolates widespread among pigs of European Union (EU) countries since the mid-1990s. Each ST comprised isolates showing similar pulsed-field gel electrophoresis (PFGE) patterns (≤6 bands difference; >82% similarity). Some CC5 PFGE subtype strains from swine were indistinguishable from hospital vancomycin-resistant enterococci (VRE) causing infections. A truncated variant of Tn1546 (encoding resistance to vancomycin) and tcrB (coding for resistance to copper) were consistently located on 150- to 190-kb plasmids (reppLG1). E. faecium CC17 (ST132) isolates from pig manure and two clinical samples showed identical PFGE profiles and contained a 60-kb mosaic plasmid (repInc18 plus reppRUM) carrying diverse Tn1546-IS1216 variants. The only Enterococcus faecalis isolate obtained from pigs (CC2-ST6) corresponded to a multidrug-resistant clone widely disseminated in hospitals in Italy, Portugal, and Spain, and both animal and human isolates harbored an indistinguishable 100-kb mosaic plasmid (reppRE25 plus reppCF10) containing the whole Tn1546 backbone. The results indicate a current intra- and international spread of E. faecium and E. faecalis clones and their plasmids among swine and humans. PMID:21227995

  13. Glycopeptide susceptibility among Danish Enterococcus faecium and Enterococcus faecalis isolates of animal and human origin and PCR identification of genes within the VanA cluster.

    PubMed Central

    Aarestrup, F M; Ahrens, P; Madsen, M; Pallesen, L V; Poulsen, R L; Westh, H

    1996-01-01

    The MICs of vancomycin and avoparcin were determined for isolates of Enterococcus faecium and isolates of Enterococcus faecalis recovered from the feces of humans and animals in Denmark. Two hundred twenty-one of 376 (59%) isolates of E. faecium and 2 of 133 (1.5%) isolates of E. faecalis were resistant to vancomycin (MICs, 128 to > or = 256 micrograms/ml), and all vancomycin-resistant isolates were resistant to avoparcin (MICs, 64 to > or = 256 micrograms/ml). All vancomycin-resistant isolates examined carried the vanA, vanX, and vanR genes, suggesting that a gene cluster similar to that of the transposon Tn1546 was responsible for the resistance. PMID:8843309

  14. Antimicrobial resistance pattern and genetic correlation in Enterococcus faecium isolated from healthy volunteers.

    PubMed

    Asadian, M; Sadeghi, J; Rastegar Lari, A; Razavi, Sh; Hasannejad Bibalan, M; Talebi, M

    2016-03-01

    Enterococci are known as a cause of nosocomial infections and this aptitude is intensified by the growth of antibiotic resistance. In the present study, Enterococcus faecium isolates from healthy volunteers were considered to determine the antibiotic resistance profiles and genetic correlation. A total 91 normal flora isolates of enterococci were included in this study. Identification of Enterococcus genus and species were done by biochemical and PCR methods, respectively. Sensitivity for 10 antibiotics was determined and genetic relatedness of all isolates was assessed using Repetitive Element Palindromic PCR (REP-PCR) followed by Pulse Field Gel Electrophoresis (PFGE) on the representative patterns. None of the isolates were resistant to teicoplanin, vancomycin, quinupristin-dalfopristin, linezolid, chloramphenicol, ampicillin and high-level gentamicin. On the other hand, the resistance rate was detected in 30.7%, 23%, and 3.29% of isolates for erythromycin, tetracycline and ciprofloxacin, respectively. The results of PFGE showed 19 (61.5% of our isolates) common types (CT) and 35 (38.5%) single types (ST) amongst the isolates. This is the first study to describe antibiotic resistance pattern and genetic relationship among normal flora enterococci in Iran. This study showed no prevalence of Vancomycin Resistant Enterococci (VRE) and high degrees of diversity among normal flora isolates by genotyping using PFGE.

  15. The mazEF toxin-antitoxin system as an attractive target in clinical isolates of Enterococcus faecium and Enterococcus faecalis.

    PubMed

    Soheili, Sara; Ghafourian, Sobhan; Sekawi, Zamberi; Neela, Vasantha Kumari; Sadeghifard, Nourkhoda; Taherikalani, Morovat; Khosravi, Afra; Ramli, Ramliza; Hamat, Rukman Awang

    2015-01-01

    The toxin-antitoxin (TA) system is a regulatory system where two sets of genes encode the toxin and its corresponding antitoxin. In this study, the prevalence of TA systems in independently isolated clinical isolates of Enterococcus faecium and Enterococcus faecalis was determined, the dominant TA system was identified, different virulence genes in E. faecium and E. faecalis were surveyed, the level of expression of the virulence and TA genes in normal and stress conditions was determined, and finally their associations with the TA genes were defined. Remarkably, the analysis demonstrated higBA and mazEF in all clinical isolates, and their locations were on chromosomes and plasmids, respectively. On the other hand, a quantitative analysis of TA and virulence genes revealed that the expression level in both genes is different under normal and stress conditions. The results obtained by anti-mazF peptide nucleic acids demonstrated that the expression level of virulence genes had decreased. These findings demonstrate an association between TA systems and virulence factors. The mazEF on the plasmids and the higBA TA genes on the chromosomes of all E. faecium and E. faecalis strains were dominant. Additionally, there was a decrease in the expression of virulence genes in the presence of anti-mazF peptide nucleic acids. Therefore, it is suggested that mazEF TA systems are potent and sensitive targets in all E. faecium and E. faecalis strains.

  16. A decade of genomic history for healthcare-associated Enterococcus faecium in the United Kingdom and Ireland

    PubMed Central

    Raven, Kathy E.; Reuter, Sandra; Reynolds, Rosy; Brodrick, Hayley J.; Russell, Julie E.; Török, M. Estée; Parkhill, Julian; Peacock, Sharon J.

    2016-01-01

    Vancomycin-resistant Enterococcus faecium (VREfm) is an important cause of healthcare-associated infections worldwide. We undertook whole-genome sequencing (WGS) of 495 E. faecium bloodstream isolates from 2001–2011 in the United Kingdom and Ireland (UK&I) and 11 E. faecium isolates from a reference collection. Comparison between WGS and multilocus sequence typing (MLST) identified major discrepancies for 17% of isolates, with multiple instances of the same sequence type (ST) being located in genetically distant positions in the WGS tree. This confirms that WGS is superior to MLST for evolutionary analyses and is more accurate than current typing methods used during outbreak investigations. E. faecium has been categorized as belonging to three clades (Clades A1, hospital-associated; A2, animal-associated; and B, community-associated). Phylogenetic analysis of our isolates replicated the distinction between Clade A (97% of isolates) and Clade B but did not support the subdivision of Clade A into Clade A1 and A2. Phylogeographic analyses revealed that Clade A had been introduced multiple times into each hospital referral network or country, indicating frequent movement of E. faecium between regions that rarely share hospital patients. Numerous genetic clusters contained highly related vanA-positive and -negative E. faecium, which implies that control of vancomycin-resistant enterococci (VRE) in hospitals also requires consideration of vancomycin-susceptible E. faecium. Our findings reveal the evolution and dissemination of hospital-associated E. faecium in the UK&I and provide evidence for WGS as an instrument for infection control. PMID:27527616

  17. Relations between the occurrence of resistance to antimicrobial growth promoters among Enterococcus faecium isolated from broilers and broiler meat.

    PubMed

    Emborg, H-D; Andersen, J S; Seyfarth, A M; Andersen, S R; Boel, J; Wegener, H C

    2003-08-01

    From 1995 to 2001, Enterococcus faecium isolates were collected from broiler flocks at slaughter and broiler meat products at retail outlets and were tested for susceptibility to classes of antimicrobials used for growth promotion in broilers in Denmark, namely: evernimicin, glycopeptide, macrolide and streptogramin. By February 1998, all antimicrobial growth promoters (AGPs) were withdrawn from the Danish broiler production. The present study investigates, by logistic regression analyses, the (1) changes in the occurrence of AGP resistance among E. faecium from broilers and broiler meat from the fourth quarter of 1995 to the fourth quarter of 2001 and (2) relations between the occurrence of AGP resistance among E. faecium isolates from Danish broilers and AGP resistance among E. faecium isolates from the broiler meat of Danish and unknown origin collected in the same quarter within the year. In the present study, we showed that after the AGP withdrawal, a significant decline in resistance to avilamycin, erythromycin, vancomycin and virginiamycin was observed among E. faecium from broilers and broiler meat. In addition, a decline in the occurrence of AGP resistance among E. faecium from Danish broilers was associated with a decrease in the predicted probability of isolating an AGP-resistant E. faecium isolate from a randomly selected broiler meat product. In the analyses "relations between the occurrence of AGP resistance among E. faecium isolated from broilers and broiler meat collected in the same quarter" errors in the explanatory variable were expected. Therefore, a simulation study was performed to validate the results from logistic regression analyses. The results obtained by the two methods were similar.

  18. Increase in Bloodstream Infection Due to Vancomycin-Susceptible Enterococcus faecium in Cancer Patients: Risk Factors, Molecular Epidemiology and Outcomes

    PubMed Central

    Gudiol, Carlota; Ayats, Josefina; Camoez, Mariana; Domínguez, M. Ángeles; García-Vidal, Carolina; Bodro, Marta; Ardanuy, Carmen; Obed, Mora; Arnan, Montserrat; Antonio, Maite; Carratalà, Jordi

    2013-01-01

    We conducted a prospective study to assess the risk factors, molecular epidemiology and outcome of bloodstream infection (BSI) due to Enterococcus faecium in hospitalized cancer patients. Between 2006 and 2012, a significant increase in vancomycin-susceptible E. faecium BSI was observed among cancer patients. Comparison of 54 episodes of BSI due to E. faecium with 38 episodes of BSI due to E. faecalis showed that previous use of carbapenems was the only independent risk factor for E. faecium acquisition (OR 10.24; 95% CI, 1.35-77.66). All E. faecium isolates were susceptible to glycopeptides, whereas 97% showed high-level resistance to ampicillin and ciprofloxacin. All 30 isolates available for genotyping belonged to the hospital-associated E. faecium lineages 17, 18 and 78. After 2009, most of the isolates belonged to ST117 (lineage 78). Patients with E. faecium BSI were more likely to receive inadequate initial empirical antibiotic therapy than patients with E. faecalis BSI, and time to adequate empirical antibiotic therapy was also longer in the former group. No significant differences were found between the two groups regarding early and overall case-fatality rates. Independent risk factors for overall case-fatality were current corticosteroids (OR 4.18; 95% CI, 1.34-13.01) and intensive care unit admission (OR 9.97; 95% CI, 1.96-50.63). The emergence of E. faecium among cancer patients is a concern since there are limited treatment options and it may presage the emergence of vancomycin-resistant enterococci. A rationale approach that combines infection control with antimicrobial stewardship. PMID:24069339

  19. Virulence Genes among Enterococcus faecalis and Enterococcus faecium Isolated from Coastal Beaches and Human and Nonhuman Sources in Southern California and Puerto Rico

    PubMed Central

    Talavera, Ginamary Negrón; Hernández, Luis A. Ríos; Ambrose, Richard F.; Jay, Jennifer A.

    2016-01-01

    Most Enterococcus faecalis and E. faecium are harmless to humans; however, strains harboring virulence genes, including esp, gelE, cylA, asa1, and hyl, have been associated with human infections. E. faecalis and E. faecium are present in beach waters worldwide, yet little is known about their virulence potential. Here, multiplex PCR was used to compare the distribution of virulence genes among E. faecalis and E. faecium isolated from beaches in Southern California and Puerto Rico to isolates from potential sources including humans, animals, birds, and plants. All five virulence genes were found in E. faecalis and E. faecium from beach water, mostly among E. faecalis. gelE was the most common among isolates from all source types. There was a lower incidence of asa1, esp, cylA, and hyl genes among isolates from beach water, sewage, septage, urban runoff, sea wrack, and eelgrass as compared to human isolates, indicating that virulent strains of E. faecalis and E. faecium may not be widely disseminated at beaches. A higher frequency of asa1 and esp among E. faecalis from dogs and of asa1 among birds (mostly seagull) suggests that further studies on the distribution and virulence potential of strains carrying these genes may be warranted. PMID:27144029

  20. Dispersion of Multidrug-Resistant Enterococcus faecium Isolates Belonging to Major Clonal Complexes in Different Portuguese Settings▿

    PubMed Central

    Freitas, Ana R.; Novais, Carla; Ruiz-Garbajosa, Patricia; Coque, Teresa M.; Peixe, Luísa

    2009-01-01

    The population structure of 56 Enterococcus faecium isolates selected from a collection of enterococci from humans, animals, and the environment in Portugal (1997 to 2007) was analyzed by multilocus sequence typing. We identified 41 sequence types clustering into CC17, CC5, CC9, CC22 and CC94, all clonal lineages comprising isolates from different hosts. Our findings highlight the role of community-associated hosts as reservoirs of enterococci able to cause human infections. PMID:19447948

  1. The first report of the vanC₁ gene in Enterococcus faecium isolated from a human clinical specimen.

    PubMed

    Sun, Mingyue; Wang, Yue; Chen, Zhongju; Zhu, Xuhui; Tian, Lei; Sun, Ziyong

    2014-09-01

    The vanC₁ gene, which is chromosomally located, confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Enterococcus faecium TJ4031 was isolated from a blood culture and harbours the vanC₁gene. Polymerase chain reaction (PCR) assays were performed to detect vanXYc and vanTc genes. Only the vanXYc gene was found in the E. faecium TJ4031 isolate. The minimum inhibitory concentrations of vancomycin and teicoplanin were 2 µg/mL and 1 µg/mL, respectively. Real-time reverse transcription-PCR results revealed that the vanC₁ and vanXYc genes were not expressed. Pulsed-field gel electrophoresis and southern hybridisation results showed that the vanC₁ gene was encoded in the chromosome. E. faecalis isolated from animals has been reported to harbour vanC₁gene. However, this study is the first to report the presence of the vanC₁gene in E. faecium of human origin. Additionally, our research showed the vanC₁gene cannot serve as a species-specific gene of E. gallinarum and that it is able to be transferred between bacteria. Although the resistance marker is not expressed in the strain, our results showed that E. faecium could acquire the vanC₁gene from different species.

  2. Role of Combination Antimicrobial Therapy for Vancomycin-Resistant Enterococcus faecium Infections: Review of the Current Evidence.

    PubMed

    Yim, Juwon; Smith, Jordan R; Rybak, Michael J

    2017-03-08

    Enterococcus species are the second most common cause of nosocomial infections in the United States and are particularly concerning in critically ill patients with preexisting comorbid conditions. Rising resistance to antimicrobials that were historically used as front-line agents for treatment of enterococcal infections, such as ampicillin, vancomycin, and aminoglycosides, further complicates the treatment of these infections. Of particular concern are Enterococcus faecium strains that are associated with the highest rate of vancomycin resistance. The introduction of antimicrobial agents with specific activity against vancomycin-resistant Enterococcus (VRE) faecium including daptomycin, linezolid, quinupristin-dalfopristin, and tigecycline did not completely resolve this clinical dilemma. In this review, the mechanisms of action and resistance to currently available anti-VRE antimicrobial agents including newer agents such as oritavancin and dalbavancin will be presented. In addition, novel combination therapies including β-lactams and fosfomycin, and the promising results from in vitro, animal studies, and clinical experience in the treatment of VRE faecium will be discussed. This article is protected by copyright. All rights reserved.

  3. Assessment of virulence factors, antibiotic resistance and amino-decarboxylase activity in Enterococcus faecium MXVK29 isolated from Mexican chorizo.

    PubMed

    Alvarez-Cisneros, Y M; Fernández, F J; Sainz-Espuñez, T; Ponce-Alquicira, E

    2017-02-01

    Enterococcus faecium MXVK29 has the ability to produce an antimicrobial compound that belongs to Class IIa of the Klaenhammer classification, and could be used as part of a biopreservation technology through direct inoculation of the strain as a starter or protective culture. However, Enterococcus is considered as an opportunistic pathogen, hence, the purpose of this work was to study the food safety determinants of E. faecium MXVK29. The strain was sensitive to all of the antibiotics tested (penicillin, tetracycline, vancomycin, erythromycin, chloramphenicol, gentamicin, neomycin, kanamycin and netilmicin) and did not demonstrate histamine, cadaverine or putrescine formation. Furthermore, tyrosine-decarboxylase activity was detected by qualitative assays and PCR. Among the virulence factors analysed for the strain, only the genes encoding the sexual pheromone cCF10 precursor lipoprotein (ccf) and cell-wall adhesion (efaAfm ) were amplified. The presence of these genes has low impact on pathogenesis, as there are no other genes encoding for virulence factors, such as aggregation proteins. Therefore, Enterococcus faecium could be employed as part of a bioconservation method, because it does not produce risk factors for consumer's health; in addition, it could be used as part of the hurdle technology in foods.

  4. Diversity of plasmids and Tn1546-type transposons among VanA Enterococcus faecium in Poland.

    PubMed

    Wardal, E; Kuch, A; Gawryszewska, I; Żabicka, D; Hryniewicz, W; Sadowy, E

    2017-02-01

    The objective of this study was to investigate the antimicrobial resistance, Tn1546 transposon variability and plasmid diversity among Polish vancomycin-resistant Enterococcus faecium (VREfm) isolates of VanA phenotype in the context of their clonal structure. Two hundred sixteen clinical VREfm isolates collected between 1997 and 2010 were studied by antimicrobial susceptibility testing, MLST, MLVA and detection of IS16, esp Efm, pilA, intA and plasmid-specific genes by PCR. Tn1546 structure was revealed by overlapping PCR and sequencing. Selected isolates were subjected to PFGE-S1 and Southern hybridization analyses. The vast majority of the isolates (95.8 %) belonged to lineages 17/18 (during the whole study period 1997-2010) and 78 (mostly in 2006-2010) of hospital-adapted meroclone of E. faecium. All isolates displayed a multi-drug resistance phenotype. Twenty-eight Tn1546 types (including 26 novel ones) were associated with eight different ISs (IS1216, IS1251, ISEfa4, ISEfa5, ISEfm2, ISEf1, IS3-like, ISEfm1-like). The vanA-determinant was typically located on plasmids, which most commonly carried rep2pRE25, rep17pRUM, rep18pEF418, rep1pIP501, ω-ε-ζ and axe-txe genes. VanA isolates from 1997-2005 to 2006-2010 differed in clonal composition, prevalence of gentamicin- and tetracycline-resistance and plasmidome. Our analysis revealed high complexity of Tn1546-type transposons and vanA-plasmids, and suggested that diverse genetic events, such as conjugation transfer, recombination, chromosomal integration and DNA mutations shaped the structure of these elements among Polish VREfm.

  5. Detection of a cfr(B) Variant in German Enterococcus faecium Clinical Isolates and the Impact on Linezolid Resistance in Enterococcus spp.

    PubMed Central

    Fleige, Carola; Klare, Ingo; Fiedler, Stefan; Mischnik, Alexander; Mutters, Nico T.; Dingle, Kate E.; Werner, Guido

    2016-01-01

    The National Reference Centre for Staphylococci and Enterococci in Germany has received an increasing number of clinical linezolid-resistant E. faecium isolates in recent years. Five isolates harbored a cfr(B) variant gene locus the product of which is capable of conferring linezolid resistance. The cfr(B)-like methyltransferase gene was also detected in Clostridium difficile. Antimicrobial susceptibility was determined for cfr(B)-positive and linezolid-resistant E. faecium isolates and two isogenic C. difficile strains. All strains were subjected to whole genome sequencing and analyzed with respect to mutations in the 23S rDNA, rplC, rplD and rplV genes and integration sites of the cfr(B) variant locus. To evaluate methyltransferase function, the cfr(B) variant of Enterococcus and Clostridium was expressed in both E. coli and Enterococcus spp. Ribosomal target site mutations were detected in E. faecium strains but absent in clostridia. Sequencing revealed 99.9% identity between cfr(B) of Enterococcus and cfr of Clostridium. The methyltransferase gene is encoded by transposon Tn6218 which was present in C. difficile Ox3196, truncated in some E. faecium and absent in C. difficile Ox3206. The latter finding explains the lack of linezolid and chloramphenicol resistance in C. difficile Ox3206 and demonstrates for the first time a direct correlation of elevated linezolid MICs in C. difficile upon cfr acquisition. Tn6218 insertion sites revealed novel target loci for integration, both within the bacterial chromosome and as an integral part of plasmids. Importantly, the very first plasmid-association of a cfr(B) variant was observed. Although we failed to measure cfr(B)-mediated resistance in transformed laboratory strains the occurrence of the multidrug resistance gene cfr on putatively highly mobile and/or extrachromosomal DNA in clinical isolates is worrisome with respect to dissemination of antibiotic resistances. PMID:27893790

  6. Evaluation of a novel chromogenic agar medium for isolation and differentiation of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis isolates.

    PubMed

    Ledeboer, Nathan A; Das, Kingshuk; Eveland, Michael; Roger-Dalbert, Céline; Mailler, Sandrine; Chatellier, Sonia; Dunne, William Michael

    2007-05-01

    The development of reliable and rapid methods for the identification of patients colonized with vancomycin-resistant enterococci (VRE) is central to the containment of this agent within a hospital environment. To this end, we evaluated a prototype chromogenic agar medium (VRE-BMX; bioMérieux, Marcy l'Etoile, France) used to recover VRE from clinical specimens. This medium can also identify isolated colonies as either vancomycin-resistant Enterococcus faecium or Enterococcus faecalis, based on distinct colony colors. We compared the performance of VRE-BMX with bile esculin azide agar supplemented with vancomycin (BEAV). For this study, 147 stool samples were plated on each test medium and examined after 24 and 48 h of incubation. At 24 h, the sensitivity and specificity of each medium were as follows: BEAV, 90.9% and 89.9%, respectively; VRE-BMX, 96.4% and 96.6%, respectively. The positive predictive values (PPV) of VRE-BMX and BEAV at 24 h were 89.8% and 80.7%, respectively. VRE-BMX provided the identification of 10 isolates of vancomycin-resistant E. faecalis and 4 isolates of vancomycin-resistant E. faecium that were not recovered by BEAV. Further, VRE-BMX was capable of identifying patients colonized with both E. faecium and E. faecalis, a feature useful for infection control purposes that is not a function of BEAV. In terms of the recovery of vancomycin-resistant E. faecium and E. faecalis, the sensitivity and PPV were as follows: BEAV, 75.7% and 74.6%, respectively; VRE-BMX, 95.5% and 91.3%, respectively. In this initial evaluation, we found that VRE-BMX provided improved recovery of VRE from stool specimens, with the added advantage of being able to differentiate between vancomycin-resistant E. faecalis and E. faecium. Extending the incubation period beyond 24 h did not significantly improve the recovery of VRE and resulted in decreased specificity.

  7. Effects of the Probiotic Enterococcus faecium and Pathogenic Escherichia coli Strains in a Pig and Human Epithelial Intestinal Cell Model

    PubMed Central

    Lodemann, Ulrike; Strahlendorf, Julia; Schierack, Peter; Klingspor, Shanti; Aschenbach, Jörg R.

    2015-01-01

    The aim of this study has been to elucidate the effect of the probiotic Enterococcus faecium NCIMB 10415 on epithelial integrity in intestinal epithelial cells and whether pre- and coincubation with this strain can reproducibly prevent damage induced by enterotoxigenic (ETEC) and enteropathogenic Escherichia coli (EPEC). Porcine (IPEC-J2) and human (Caco-2) intestinal epithelial cells were incubated with bacterial strains and epithelial integrity was assessed by measuring transepithelial electrical resistance (TEER) and mannitol flux rates. E. faecium alone increased TEER of Caco-2 cells without affecting mannitol fluxes whereas the E. coli strains decreased TEER and concomitantly increased mannitol flux rates in both cell lines. Preincubation with E. faecium had no effect on the TEER decrease induced by E. coli in preliminary experiments. However, in a second set of experiments using a slightly different protocol, E. faecium ameliorated the TEER decrease induced by ETEC at 4 h in IPEC-J2 and at 2, 4, and 6 h in Caco-2 cells. We conclude that E. faecium positively affected epithelial integrity in monoinfected Caco-2 cells and could ameliorate the damage on TEER induced by an ETEC strain. Reproducibility of the results is, however, limited when experiments are performed with living bacteria over longer periods. PMID:25883829

  8. Enterococcus faecium LKE12 Cell-Free Extract Accelerates Host Plant Growth via Gibberellin and Indole-3-Acetic Acid Secretion.

    PubMed

    Lee, Ko-Eun; Radhakrishnan, Ramalingam; Kang, Sang-Mo; You, Young-Hyun; Joo, Gil-Jae; Lee, In-Jung; Ko, Jae-Hwan; Kim, Jin-Ho

    2015-09-01

    The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA1, GA3, GA7, GA8, GA9, GA12, GA19, GA20, GA24, and GA53), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.

  9. Effects of the probiotic Enterococcus faecium NCIMB 10415 on selected lactic acid bacteria and enterobacteria in co-culture.

    PubMed

    Starke, I C; Zentek, J; Vahjen, W

    2015-01-01

    Enterococcus faecium NCIMB 10415 is used as a probiotic for piglets and has been shown to modify the porcine intestinal microbiota. However, the mode of action of this probiotic modification is still unclear. One possible explanation is the direct growth inhibiting or stimulating effect of the probiotic on other indigenous bacteria. Therefore, the aim of the present study was to examine the growth interactions of the probiotic with different indigenous porcine bacteria in vitro. Reference strains were cultivated with the probiotic E. faecium strain NCIMB10415 (SF68) in a checkerboard assay with 102 to 105 cells/ml inoculum per strain. Growth kinetics were recorded for 8 h and used to determine specific growth of the co-cultures. Additionally, total DNA was extracted from the co-cultures at the end of the incubation to verify which strain in the co-culture was affected. Co-cultivation with eight Enterococcus spp. tester strains showed strain-specific growth differences. Three of four E. faecium strains were not influenced by the probiotic strain. PCR results showed reduced growth of the probiotic strain in co-culture with E. faecium DSM 6177. Three of four Enterococcus faecalis strains showed reduced specific growth in co-culture with the probiotic strain. However, E. faecalis DSM 20478 impaired growth of the probiotic E. faecium strain. The growth of Lactobacillus johnsonii DSM 10533 and Lactobacillus reuteri DSM 20016 was enhanced in co-culture with the probiotic strain, but co-cultivations with Lactobacillus mucosae DSM13345 or Lactobacillus amylovorus DSM10533 showed no differences. Co-cultures with the probiotic E. faecium showed no impact on the growth rate of four different enterobacterial reference strains (2 strains of Salmonella enterica and 2 strains of Escherichia coli), but PCR results showed reduced cell numbers for a pathogenic E. coli isolate at higher concentration of the probiotic strain. As the in vitro effect of the probiotic E. faecium on

  10. Diversity of clones and genotypes among vancomycin-resistant clinical Enterococcus isolates recovered in a Spanish hospital.

    PubMed

    López, María; Cercenado, Emilia; Tenorio, Carmen; Ruiz-Larrea, Fernanda; Torres, Carmen

    2012-10-01

    Forty-three vancomycin-resistant enterococci (VRE) from different patients were recovered in a Spanish Hospital (2003-2010), representing 0.4% of the total of enterococci recovered. Mechanisms detected were vanA (five Enterococcus faecium, two E. faecalis), vanB2 (seven E. faecium, five E. faecalis), vanB1 (one E. faecalis), and vanC1/2 (22 E. gallinarum, 1 E. casseliflavus). Four different Tn1546 structures were found among the seven vanA strains, three of them with insertions (ISEf1 or IS1542) or deletions. Most of the VRE presented a multiresistance phenotype and harbored different resistance genes [erm(B), tet(M), tet(L), ant(6)-Ia, aac(6')-aph(2''), aph(3')-IIIa, and catA]. Sixteen unrelated pulsotypes were detected among the 20 vanA/vanB E. faecalis and E. faecium isolates by pulsed-field-gel-electrophoresis and 11 unrelated pulsotypes among the 22 E. gallinarum isolates. Six different sequence types (ST) were demonstrated among the 12 vancomycin-resistant E. faecium strains (one of them new), and 5 were included into the clonal-complex (CC) CC17. Five different ST were detected among the eight E. faecalis strains. The esp gene was detected in 58% and 25% of E. faecium and E. faecalis strains, respectively, and the hyl gene in 78% and 89%, respectively. A high diversity of clones and genotypes of VRE were detected in this hospital.

  11. Biofilms of Enterococcus faecalis and Enterococcus faecium isolated from the processing of ricotta and the control of these pathogens through cleaning and sanitization procedures.

    PubMed

    da Silva Fernandes, Meg; Kabuki, Dirce Yorika; Kuaye, Arnaldo Yoshiteru

    2015-05-04

    The biofilm formation of Enterococcus faecalis and Enterococcus faecium isolated from the processing of ricotta on stainless steel coupons was evaluated, and the effect of cleaning and sanitization procedures in the control of these biofilms was determined. The formation of biofilms was observed while varying the incubation temperature (7, 25 and 39°C) and time (0, 1, 2, 4, 6 and 8 days). At 7°C, the counts of E. faecalis and E. faecium were below 2 log10 CFU/cm(2). For the temperatures of 25 and 39°C, after 1 day, the counts of E. faecalis and E. faecium were 5.75 and 6.07 log10 CFU/cm(2), respectively, which is characteristic of biofilm formation. The tested sanitation procedures a) acid-anionic tensioactive cleaning, b) anionic tensioactive cleaning+sanitizer and c) acid-anionic tensioactive cleaning+sanitizer were effective in removing the biofilms, reducing the counts to levels below 0.4 log10 CFU/cm(2). The sanitizer biguanide was the least effective, and peracetic acid was the most effective. These studies revealed the ability of enterococci to form biofilms and the importance of the cleaning step and the type of sanitizer used in sanitation processes for the effective removal of biofilms.

  12. RelA Mutant Enterococcus faecium with Multiantibiotic Tolerance Arising in an Immunocompromised Host

    PubMed Central

    Honsa, Erin S.; Mhaissen, Mohammed N.; Frank, Matthew; Shaker, Jessica; Iverson, Amy; Rubnitz, Jeffrey; Hayden, Randall T.; Lee, Richard E.; Rock, Charles O.; Tuomanen, Elaine I.

    2017-01-01

    ABSTRACT Serious bacterial infections in immunocompromised patients require highly effective antibacterial therapy for cure, and thus, this setting may reveal novel mechanisms by which bacteria circumvent antibiotics in the absence of immune pressure. Here, an infant with leukemia developed vancomycin-resistant Enterococcus faecium (VRE) bacteremia that persisted for 26 days despite appropriate antibiotic therapy. Sequencing of 22 consecutive VRE isolates identified the emergence of a single missense mutation (L152F) in relA, which constitutively activated the stringent response, resulting in elevated baseline levels of the alarmone guanosine tetraphosphate (ppGpp). Although the mutant remained susceptible to both linezolid and daptomycin in clinical MIC testing and during planktonic growth, it demonstrated tolerance to high doses of both antibiotics when growing in a biofilm. This biofilm-specific gain in resistance was reflected in the broad shift in transcript levels caused by the mutation. Only an experimental biofilm-targeting ClpP-activating antibiotic was able to kill the mutant strain in an established biofilm. The relA mutation was associated with a fitness trade-off, forming smaller and less-well-populated biofilms on biological surfaces. We conclude that clinically relevant relA mutations can emerge during prolonged VRE infection, causing baseline activation of the stringent response, subsequent antibiotic tolerance, and delayed eradication in an immunocompromised state. PMID:28049149

  13. Raising the Alarmone: Within-Host Evolution of Antibiotic-Tolerant Enterococcus faecium

    PubMed Central

    2017-01-01

    ABSTRACT Enterococci are ancient commensal bacteria that recently emerged as leading causes of antibiotic-resistant, hospital-acquired infection. Vancomycin-resistant enterococci (VRE) epitomize why drug-resistant enterococcal infections are a problem: VRE readily colonize the antibiotic-perturbed gastrointestinal (GI) tract where they amplify to large numbers, and from there, they infect other body sites, including the bloodstream, urinary tract, and surgical wounds. VRE are resistant to many antimicrobials and host defenses, which facilitates establishment at the site of infection and confounds therapeutic clearance. Having evolved to colonize the GI tract, VRE are comparatively ill adapted to the human bloodstream. A recent study by Honsa and colleagues (E. S. Honsa et al., mBio 8:e02124-16, 2017, https://doi.org/10.1128/mBio.02124-16) found that a strain of vancomycin-resistant Enterococcus faecium evolved antibiotic tolerance within the bloodstream of an immunocompromised host by activating the stringent response through mutation of relA. Precisely how VRE colonize and infect and the selective pressures that led to the outgrowth of relA mutants are the subjects of ongoing research. PMID:28223450

  14. In vitro probiotic profiling of novel Enterococcus faecium and Leuconostoc mesenteroides from Tunisian freshwater fishes.

    PubMed

    El-Jeni, Rim; El Bour, Monia; Calo-Mata, Pilar; Böhme, Karola; Fernández-No, Inmaculada C; Barros-Velázquez, Jorge; Bouhaouala-Zahar, Balkiss

    2016-01-01

    Novel lactic acid bacteria isolated from different organs of freshwater fish were examined for their potential application as probiotics in raw and processed foods. Four isolates of Enterococcus faecium and Leuconostoc mesenteroides were identified at the molecular level by 16S rRNA sequencing and random amplification of polymorphic DNA - polymerase chain reaction, and their antimicrobial activity against a panel of pathogens and food-poisoning bacteria was investigated. The whole bacteriocins of the 4 isolates were characterized by enterobacterial repetitive intergenic consensus sequences in PCR. The isolates exhibited high inhibitory activities against food-borne pathogens and spoilage microbial species and have significant probiotic profiles, since they survived at pH 3.0 and in the presence of bile salts, pancreatin, and pepsin, without any detectable hemolytic activity. Further, moderate heat resistance, adhesion ability to steel surfaces, and sensitivity to clinically relevant antimicrobial agents were revealed for all the isolates. These results highlight the specific probiotic properties of the strains and give evidence for potential application in minimally processed foods subjected to moderate heat processing.

  15. Clonal Spread of a Vancomycin-Resistant Enterococcus faecium Strain among Bloodstream-Infecting Isolates in Italy

    PubMed Central

    Stampone, Lucia; Del Grosso, Maria; Boccia, Delia; Pantosti, Annalisa

    2005-01-01

    Recent data indicated that the rate of vancomycin resistance in bloodstream-infecting enterococcal isolates in Italy is one of the highest in Europe. The aims of this study were to characterize bloodstream-infecting vancomycin-resistant enterococci (VRE) obtained from various Italian hospitals and to establish whether the isolates were clonally related. During the years 2001 to 2003, a total of 39 VRE isolates were obtained from 19 hospital laboratories in various areas of Italy. Species identification and resistance genotypes of the isolates were obtained by multiplex PCR. Further characterization included antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA, detection of virulence genes (esp and hyl), and multilocus sequence typing (MLST) of selected isolates. VRE were identified as 31 Enterococcus faecium (VREfm) isolates and 8 E. faecalis isolates. All but one isolate carried the vanA gene; one VREfm isolate carried the vanB gene. Analysis of the PFGE profiles showed that 28 VREfm isolates shared a similar electrophoretic profile, designed type 1, and were clonally related. All type 1 isolates were resistant to ampicillin, streptomycin, gentamicin, and rifampin and were positive for the esp gene. MLST identified an allelic profile (ST78) comprising purK allele 1, belonging to the C1 clonal lineage, characteristic of human infection and hospital outbreak isolates. The vanB-carrying VREfm isolate, of PFGE type 2, was shown to be a single-locus variant of ST78. Our data indicate that the recent increase in the number of bloodstream infections caused by VRE in Italy is due to the spread of a hospital-adapted, multidrug-resistant VREfm clone belonging to an internationally disseminated lineage. PMID:15814968

  16. Biofilm formation on polystyrene under different temperatures by antibiotic resistant Enterococcus faecalis and Enterococcus faecium isolated from food.

    PubMed

    Marinho, A R; Martins, P D; Ditmer, E M; d'Azevedo, P A; Frazzon, J; Van Der Sand, S T; Frazzon, A P G

    2013-01-01

    The ability of antibiotic resistant E. faecalis and E. faecium isolated from food to form biofilm at different temperatures in the absence or presence of 0.75% glucose was evaluated. A synergistic effect on biofilm at 10 °C, 28 °C, 37 °C and 45 °C and glucose was observed for E. faecalis and E. faecium.

  17. Effects of oral Enterococcus faecium strain DSM 10663 NCIMB 10415 on diarrhoea patterns and performance of sucking piglets.

    PubMed

    Büsing, K; Zeyner, A

    2015-03-01

    Effects of probiotic Enterococcus faecium DMS 10663 NCIMB 10415 on diarrhoea and performance of sucking piglets were evaluated in a double-blind, placebo-controlled study. Piglets from treatment group (TG, n=56) and placebo group (PG, n=53) sows were included in the study. Immediately after birth and at day 2 and 3 post natum, each of the TG piglets received 2.8×10(9) colony forming units (cfu) per os. From day 4 until weaning (day 26), 1.26×10(9) cfu E. faecium/piglet were given twice a day via a liquid additive. Piglets already suffering from diarrhoea additionally got a glucose-electrolyte solution enriched with 2.9×10(8) (week 1) and 5.8×10(8) (week 2) cfu E. faecium/day. PG piglets received corresponding placebo preparations. A score was defined to characterise the severity of diarrhoea, including accompanying symptoms. The counts of viable born, stillborn and weaned piglets were similar in TG and PG litters (P>0.05). The probiotic treatment mitigated incidence and severity of diarrhoea (P<0.05) with no impact on diarrhoea length (P>0.05). Probiotic treatment improved daily weight gain (P<0.05) yet with no provable effect on body weight at weaning (P>0.05). The additional supply of E. faecium in piglets suffering from diarrhoea had no further beneficial effect.

  18. Use of antimicrobial growth promoters in food animals and Enterococcus faecium resistance to therapeutic antimicrobial drugs in Europe.

    PubMed Central

    Wegener, H. C.; Aarestrup, F. M.; Jensen, L. B.; Hammerum, A. M.; Bager, F.

    1999-01-01

    Supplementing animal feed with antimicrobial agents to enhance growth has been common practice for more than 30 years and is estimated to constitute more than half the total antimicrobial use worldwide. The potential public health consequences of this use have been debated; however, until recently, clear evidence of a health risk was not available. Accumulating evidence now indicates that the use of the glycopeptide avoparcin as a growth promoter has created in food animals a major reservoir of Enterococcus faecium, which contains the high level glycopeptide resistance determinant vanA, located on the Tn1546 transposon. Furthermore, glycopeptide-resistant strains, as well as resistance determinants, can be transmitted from animals to humans. Two antimicrobial classes expected to provide the future therapeutic options for treatment of infections with vancomycin-resistant enterococci have analogues among the growth promoters, and a huge animal reservoir of resistant E. faecium has already been created, posing a new public health problem. PMID:10341169

  19. Modelling the Biphasic Growth and Product Formation by Enterococcus faecium CECT 410 in Realkalized Fed-Batch Fermentations in Whey

    PubMed Central

    Guerra, Nelson Pérez; Fajardo, Paula; Fuciños, Clara; Amado, Isabel Rodríguez; Alonso, Elisa; Torrado, Ana; Pastrana, Lorenzo

    2010-01-01

    The influence of initial pH on growth and nutrient (total sugars, nitrogen, and phosphorous) consumption by Enterococcus faecium CECT 410 was studied during batch cultures in whey. With these data, two realkalized fed-batch fermentations were developed using different feeding substrates. The shift from homolactic to mixed acid fermentation, the biphasic kinetics observed for cell growth and nitrogen consumption and the increase in the concentrations of biomass and products (lactic acid, acetic acid, ethanol, and butane-2,3-diol) were the most noteworthy observations of these cultures. Modelling the fed-batch growth of Ent. faecium with the Logistic and bi-Logistic models was not satisfactory. However, biomass production was best mathematically described with the use of a double Monod model, which was expressed in terms of biomass, product accumulation, and nitrogen utilization. Product formation was successfully modelled with a modified form of the Luedeking and Piret model developed in this study. PMID:20689729

  20. Antibacterial potential and genetic profile of Enterococcus faecium strains isolated from human normal flora.

    PubMed

    Karimaei, Samira; Sadeghi, Javad; Asadian, Mahla; Esghaei, Maryam; Pourshafie, Mohammad Reza; Talebi, Malihe

    2016-07-01

    Enterococci have a widespread attendance in the circumference and belongs to the enteric commensal microbiota. Most of them produce the antimicrobial compounds and have an inhibition effect on pathogenic microorganisms. The objective of this study was to characterize the enterococcal strains isolated from human normal flora and assess their antibacterial activity. Enterococcal isolates were obtained from the feces of eighteen healthy humans. All enterococcal species were identified by biochemical and species-specific polymerase chain reaction (PCR). These isolates were investigated further to examine their ability to inhibit growth of Salmonella typhi, Shigella flexneri and Escherichia coli by well diffusion assay. Furthermore, antibiotic susceptibility test was performed and genetic relatedness of all isolates was evaluated by Pulse Field Gel Electrophoresis (PFGE). In all, 432 isolates were obtained from fecal samples. All of the isolates identified as Enterococcus faecium by biochemical and molecular (PCR) methods. Using repetitive element palindromic (REP)-PCR method 54 patterns have been obtained and were selected for further evaluation. The results indicated that 66%, 38% and 24% of our isolates had antimicrobial effect against S. typhi, S flexneri and enteroaggregative Escherichia coli (EAEC), respectively. On the other hand, there was no significant inhibition effect against enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC). All isolates were sensitive to vancomycin, teicoplanin, linezolid, ampicillin, chloramphenicol and gentamicin. On the other hand, the resistance rates for erythromycin, tetracycline and ciprofloxacin were 20%, 22%, and 1.8% respectively. In addition, the analysis of PFGE showed forty patterns with eight (40.7%) common types (CT) and thirty two (59.2%) single types (ST). Among eight common types, only one common type (CT5) had similar antimicrobial effect. These results suggested that enterococcal isolates obtained from

  1. Beneficial effects of probiotic cholesterol-lowering strain of Enterococcus faecium WEFA23 from infants on diet-induced metabolic syndrome in rats.

    PubMed

    Zhang, Fen; Qiu, Liang; Xu, Xiongpeng; Liu, Zhengqi; Zhan, Hui; Tao, Xueying; Shah, Nagendra P; Wei, Hua

    2017-03-01

    The aim of this study was to select probiotic Enterococcus strains that have the potential to improve metabolic syndrome (MS). Ten Enterococcus strains isolated from healthy infants were evaluated for their probiotic properties in vitro, and Enterococcus faecium WEFA23 was selected due to its cholesterol removal ability (1.89 ± 0.07 mg/10(10) cfu), highest glycodeoxycholic acid-hydrolase activity (1.86 ± 0.01 U/mg), and strong adhesion capacity to Caco-2 cells (17.90 ± 0.19%). The safety of E. faecium WEFA23 was verified by acute oral administration in mice, and it was found to have no adverse effects on general health status, bacterial translocation, and gut mucosal histology. Moreover, the beneficial effects of E. faecium WEFA23 on high-fat diet-induced MS in rats were investigated, and we found WEFA23 significantly decreased body weight, serum lipid levels (total cholesterol, triacylglycerols, and low-density lipoprotein cholesterol), blood glucose level, and insulin resistance in rats fed with a high-fat diet. This indicated that administration of E. faecium WEFA23 improved almost all key markers of MS, including obesity, hyperlipidemia, hyperglycemia, and insulin resistance. Our results supported E. faecium WEFA23 as a candidate for cholesterol-lowering dairy products and improvement of MS. Our research provided novel insights on Enterococcus as a strategy to combat MS.

  2. Effect of Enterococcus faecium AL41 and Thymus vulgaris essential oil on small intestine integrity and antioxidative status of laying hens.

    PubMed

    Placha, I; Simonova, M Pogany; Cobanova, K; Laukova, A; Faix, S

    2010-10-01

    We investigated the effect of Enterococcus faecium on phagocytic activity, antioxidative status in vivo and the effect of E. faecium and 0.4% concentration of Thymus vulgaris essential oil (EO) on the duodenal tissue integrity in vitro in laying hens. The birds were fed the same standard diets and were divided into four groups. E. faecium was added to the drinking water for the second and fourth groups. EO was added to special chambers for measuring trans-epithelial electrical resistance (TEER) for the third and fourth groups only. TEER was lower in groups where EO was added, but in the group with E. faecium TEER was not changed significantly. Our results show that EO at 0.4% concentration may negatively affect intestine integrity, and the probiotic strain E. faecium AL41 is able to eliminate this effect and can strengthen non-specific immunity. To confirm our findings further histopathological investigations of intestinal tissue are needed.

  3. Intestinal microbiota and oral administration of Enterococcus faecium associated with the growth performance of new-born piglets.

    PubMed

    Wang, Y B; Du, W; Fu, A K; Zhang, X P; Huang, Y; Lee, K H; Yu, K; Li, W F; Li, Y L

    2016-09-01

    The oral administration of Enterococcus faecium EF1 to new-born suckling and weaning piglets along with their growth performances and intestinal microbiota was investigated in this study. Twenty-four new-born piglets were initially divided into 2 groups. The probiotics group received 2 ml of 10% sterilised skimmed milk by oral gavage supplemented with 6×10(8) cfu/ml viable E. faecium EF1 at the first, the third and the fifth day after birth, while the control group received 2 ml of 10% sterilised skimmed milk without probiotics at the same time. Results showed that oral administration of E. faecium EF1 was associated with a remarkable increase on the body weight of piglets for both suckling and weaning periods, by 30.73% (P<0.01) and 320.84% (P<0.01), and also decreased the diarrhoea rate, by 43.21% (P<0.05) and 71.42% (P<0.05), respectively. In addition, 454-pyrosequencing analysis revealed that there was no significant difference in the intestinal microbial diversity of the suckling piglets between the two groups; nevertheless, when compared to the control group, the relative abundance of Firmicutes in the probiotics group was substantially augmented, while the relative abundance of Proteobacteria, Bacteroidetes and Fusobacteria diminished. However, results indicated that oral administration of E. faecium EF1 did not have any influence on the relative abundance of Firmicutes in weaning piglets rather than increasing the relative abundance of Bacteroidetes and decreasing the relative abundance of Proteobacteria. Furthermore, at the level of the Firmicutes phylum, the relative abundance of Lactobacillales in the probiotic group increased significantly. These findings suggest that oral administration of E. faecium EF1 to new-born piglets could improve the growth performance and intestinal microbiota of piglets for both suckling and weaning periods.

  4. Development of a multiplex PCR for the detection of asa1, gelE, cylA, esp, and hyl genes in enterococci and survey for virulence determinants among European hospital isolates of Enterococcus faecium.

    PubMed

    Vankerckhoven, Vanessa; Van Autgaerden, Tim; Vael, Carl; Lammens, Christine; Chapelle, Sabine; Rossi, Rosaria; Jabes, Daniela; Goossens, Herman

    2004-10-01

    A multiplex PCR for the simultaneous detection of five virulence genes (asa1, gelE, cylA, esp, and hyl) in enterococci was developed. The presence of these genes was investigated in 153 clinical and 118 fecal Enterococcus faecium isolates from inpatients at an increased risk of developing infections (such as patients in intensive care units and hematology wards) from 13 hospitals in eight European countries. Of the 271 E. faecium isolates, 135 were vancomycin resistant E. faecium (VREF) isolates and 136 were vancomycin susceptible E. faecium (VSEF) isolates. Susceptibilities to ampicillin, gentamicin, streptomycin, vancomycin, teicoplanin, ramoplanin, quinupristin-dalfopristin, and linezolid were tested by the microdilution method. Overall, the prevalence of esp was significantly higher (P = 0.03) in clinical VREF isolates (92%) than in fecal VREF isolates (73%). In Italy, the prevalence of esp was significantly higher (P = 0.02) in VREF isolates (91%) than in VSEF isolates (68%), whereas in the United Kingdom, hyl was significantly more prevalent (P = 0.01) in VREF isolates (71%) than in VSEF isolates (29%). No significant differences were found for the other countries. Pulsed-field gel electrophoresis was used to check the clonality among the strains tested and showed the spread of two center-specific (esp-positive) VREF clones in Italy and one center-specific (hyl-positive) clone in the United Kingdom. These clones were resistant to ampicillin, gentamicin, and streptomycin. The multiplex PCR reported in this study is a convenient and rapid method for the simultaneous detection of the virulence genes asa1, gelE, cylA, esp, and hyl in enterococci. Molecular analysis showed the intrahospital spread of esp-positive VREF clones (in Italy) and hyl-positive VREF clones (in the United Kingdom); the role of hyl remains to be elucidated.

  5. Relations between the consumption of antimicrobial growth promoters and the occurrence of resistance among Enterococcus faecium isolated from broilers.

    PubMed Central

    Emborg, H. D.; Andersen, J. S.; Seyfarth, A. M.; Wegener, H. C.

    2004-01-01

    The present study investigates, at farm level, the effect of the time-span between sampling and the last time a particular antimicrobial growth promoter (AGP) was included in the feed on the probability of selecting an AGP-resistant Enterococcus faecium isolate from a broiler flock. The probability that a randomly selected E. faecium isolate was resistant to avilamycin, erythromycin or virginiamycin was 0.91, 0.92 and 0.84, respectively if the isolate originated from a broiler flock fed either avilamycin- or virginiamycin-supplemented feed. As the time-span between sampling and the last AGP consumption increased, the probability of isolating an E. faecium isolate resistant to a particular AGP decreased (probability <0.2 within 3-5 years after last exposure to AGPs). The decrease in probability over time showed little farm-to-farm variation. The number of times a particular AGP was given to previous flocks reared in the same house had no effect on the probability of isolating a resistant isolate. PMID:14979595

  6. Relations between the consumption of antimicrobial growth promoters and the occurrence of resistance among Enterococcus faecium isolated from broilers.

    PubMed

    Emborg, H D; Andersen, J S; Seyfarth, A M; Wegener, H C

    2004-01-01

    The present study investigates, at farm level, the effect of the time-span between sampling and the last time a particular antimicrobial growth promoter (AGP) was included in the feed on the probability of selecting an AGP-resistant Enterococcus faecium isolate from a broiler flock. The probability that a randomly selected E. faecium isolate was resistant to avilamycin, erythromycin or virginiamycin was 0.91, 0.92 and 0.84, respectively if the isolate originated from a broiler flock fed either avilamycin- or virginiamycin-supplemented feed. As the time-span between sampling and the last AGP consumption increased, the probability of isolating an E. faecium isolate resistant to a particular AGP decreased (probability <0.2 within 3-5 years after last exposure to AGPs). The decrease in probability over time showed little farm-to-farm variation. The number of times a particular AGP was given to previous flocks reared in the same house had no effect on the probability of isolating a resistant isolate.

  7. The recombinase IntA is required for excision of esp-containing ICEEfm1 in Enterococcus faecium.

    PubMed

    Top, Janetta; Sinnige, Jan C; Majoor, Eline A M; Bonten, Marc J M; Willems, Rob J L; van Schaik, Willem

    2011-02-01

    Comparative genome analysis of Enterococcus faecium recently revealed that a genomic island containing the esp gene, referred to as the esp-containing pathogenicity island (esp PAI), can be transferred by conjugation and contains a partial Tn916-like element and an integrase gene, intA. Here, we characterize the role of intA in the excision of the esp PAI. An intA insertion-deletion mutant in E. faecium E1162 (E1162ΔintA) was constructed and in trans complemented with wild-type intA (E1162ΔintA::pEF30). Circular intermediates (CI) of excised esp PAI were determined using inverse PCR analysis on purified chromosomal DNA from strains E1162, E1162Δesp, E1162ΔintA, and E1162ΔintA::pEF30. In E1162 and E1162Δesp, CI of the esp PAI were detected. No CI were detected in E1162ΔintA, while in the complemented strain E1162ΔintA::pEF30 CI formation was restored, indicating that intA is essential for excision and subsequent mobilization of the esp-containing genomic island in E. faecium. Based on the fact that this island can be mobilized and is self-transmissible, we propose to change the name of the esp PAI to ICEEfm1.

  8. Enterococcus faecium RZS C5, an interesting bacteriocin producer to be used as a co-culture in food fermentation.

    PubMed

    Leroy, F; Foulquié Moreno, M R; De Vuyst, L

    2003-12-01

    Enterocins, bacteriocins produced by enterococci, are gaining interest because of their industrial potential. Due to its bacteriocin production, Enterococcus faecium RZS C5, a natural cheese isolate, has a strong activity towards Listeria monocytogenes. For this reason, the strain may be applicable as a bacteriocin-producing co-culture in food fermentation in order to reduce the risk on Listeria outgrowth. The strain displays remarkable bacteriocin production kinetics. Whereas most lactic acid bacteria produce bacteriocin in a growth-associated way until the beginning of the stationary phase, bacteriocin production by E. faecium RZS C5 in MRS broth at controlled pH values below 7.5 is characterised by a boost of bacteriocin activity levels in the very early growth phase. In addition, bacteriocin production kinetics are closely linked to the environmental and cultural conditions. However, no straightforward statement about the effect of environmental stress on bacteriocin production can be made since the effect is dependent on the type of stress applied. Kinetic experiments in milk and on pilot scale, applying Cheddar cheese-making conditions, have indicated that the strain may be effective as a bacteriocin-producing co-culture. Further research is needed to evaluate the use of E. faecium RZS C5 as a co-culture for the production of fermented sausage.

  9. Purification of a dimeric arginine deiminase from Enterococcus faecium GR7 and study of its anti-cancerous activity.

    PubMed

    Kaur, Baljinder; Kaur, Rajinder

    2016-09-01

    The arginine deiminase (ADI, E.C 3.5.3.6) - a key enzyme of ADI pathway of Enterococcus faecium GR7 was purified to homogeneity. A sequential purification strategy involving ammonium sulfate fractionation, molecular sieve followed by Sephadex G-100 gel filtration was applied to the crude culture filtrate to obtain a pure enzyme preparation. The enzyme was purified with a fold of 16.92 and showed a final specific activity of 76.65IU/mg with a 49.17% yield. The dimeric ADI has a molecular mass of about 94,364.929Da, and comprises of hetrodimers of 49.1kDa and 46.5kDa as determined by MALDI-TOF and PAGE analysis. To assess anti-cancerous activity of ADI by MTT assay was carried out against cancer cell lines (MCF-7, Sp2/0-Ag14 and Hep-G2). Purified ADI exhibited the most profound antiproliferative activity against Hep-G2 cells; with half-maximal inhibitory concentration (IC50) of 1.95μg/ml. Purified ADI from E. faecium GR7 was observed to induce apoptosis in the Hep-G2 cells by DNA fragmentation assay. Our findings suggest the possibility of a future use of ADI from E. faecium GR7 as a potential anticancer drug.

  10. Benefits of combinative application of probiotic, enterocin M-producing strain Enterococcus faecium AL41 and Eleutherococcus senticosus in rabbits.

    PubMed

    Lauková, Andrea; Simonová, Monika Pogány; Chrastinová, Ľubica; Plachá, Iveta; Čobanová, Klaudia; Formelová, Zuzana; Chrenková, Mária; Ondruška, Ľubomír; Strompfová, Viola

    2016-03-01

    This study presents the effects of the probiotic and enterocin M-producing strain Enterococcus faecium AL41 on microbiota, phagocytic activity (PA), oxidative stress, performance and biochemical parameters when applied individually or in combination with Eleutherococcus senticosus in rabbits. The novelty of the study lies in the use of our non-rabbit-derived strain (AL41 = CCM8558) which produces new enterocin M. Ninety-six post-weaned rabbits (Hyplus breed) aged 5 weeks were divided into three experimental groups, 24 in each: E. senticosus (ES, 30 g/100 kg) in feed, E. faecium AL41 (10(9) CFU/mL marked by rifampicin to differentiate it from other enterococci) in water, and ES + AL. AL41 colonized sufficiently in rabbits to reduce coliforms, staphylococci, pseudomonads and clostridia. Slight decrease in bacteria was also found in the caecum and appendix. Phagocytic activity was significantly increased in the experimental groups compared to the control group (CG) (p < 0.001; p < 0.05). Applications did not evoke oxidative stress. Biochemical parameters in blood and caecal organic acids were slightly influenced. Average daily weight gain was slightly higher in ES and AL + ES. Combinative application of E. faecium with E. senticosus can be beneficial in rabbits. AL41 strain alone and in combination with ES produced reduction in spoilage bacteria; the highest stimulation of PA was in the AL41 + ES group.

  11. Regulation of Expression of the vanD Glycopeptide Resistance Gene Cluster from Enterococcus faecium BM4339

    PubMed Central

    Casadewall, Barbara; Reynolds, Peter E.; Courvalin, Patrice

    2001-01-01

    A new open reading frame, encoding a putative integrase-like protein, was detected downstream from the six genes of the vanD glycopeptide resistance cluster in Enterococcus faecium BM4339 (B. Casadewall and P. Courvalin, J. Bacteriol. 181:3644–3648, 1999). In this cluster, genes coding for the VanRD-VanSD two-component regulatory system were cotranscribed from the PRD promoter, whereas transcription of the vanYD, vanHD, vanD, vanXD, and intD genes was initiated from the PYD promoter located between vanSD and vanYD (the D subscript indicates that the gene is part of the vanD operon). The VanRD-VanSD regulatory system is likely to activate transcription of the resistance genes from the promoter PYD. Glycopeptide-susceptible derivatives of BM4339 were obtained by trans complementation of the frameshift mutation in the ddl gene, restoring functional d-alanine:d-alanine ligase activity in this strain. The glycopeptide-susceptible transformant BM4409, producing only d-alanyl-d-alanine-terminating peptidoglycan precursors, did not express the resistance genes encoding the VanYD d,d-carboxypeptidase, the VanHD dehydrogenase, the VanD ligase, the VanXD d,d-dipeptidase, and also the IntD integrase, although the regulatory region of the vanD cluster was still transcribed. In BM4409, the absence of VanRD-VanSD, apparently dependent, transcription from promoter PYD correlated with the lack of d-alanyl-d-lactate-terminating precursors. The vanXD gene was transcribed in BM4339, but detectable amounts of VanXD d,d-dipeptidase were not synthesized. However, the gene directed synthesis of an active enzyme when cloned on a multicopy plasmid in Escherichia coli, suggesting that the enzyme was unstable in BM4339 or that it had very low activity that was detectable only under conditions of high gene dosage. This activity is not required for glycopeptide resistance in BM4339, since this strain cannot synthesize d-alanyl-d-alanine. PMID:11344152

  12. Enterococcus faecium EK13--an enterocin a-producing strain with probiotic character and its effect in piglets.

    PubMed

    Strompfová, Viola; Marcináková, Miroslava; Simonová, Monika; Gancarcíková, Sona; Jonecová, Zuzana; Sciranková, Luboslava; Koscová, Jana; Buleca, Viktor; Cobanová, Klaudia; Lauková, Andrea

    2006-01-01

    The experiment was conducted to determine the effects of the inoculation of the probiotic and enterocin A-producing strain Enterococcus faecium EK13 on selected parameters of metabolic profile, gut microflora, growth, and health in newborn piglets of Slovak White Improved. Piglets for study were divided into two groups: one group (EK13 group, n=8) received strain EK13 per os once daily for 7 days (2ml per piglet, 10(9)CFU/mL of saline buffer). The control group of piglets (n=7) was given placebo-saline buffer. The experiment lasted 14 days. After 7 days, strain EK13 reached 9.8 log(10) CFU/g in faeces of E. faecium EK13 treated piglets while counts of Escherichia coli were significantly lower (P<0.01) than in piglets of the control group. The concentrations of total serum protein, calcium, haemoglobin, haematocrit, red blood cell count and index of phagocytic activity of leukocytes were significantly higher after application of strain EK13. On the other hand, cholesterol was significantly lower in the EK13 group of animals. On day 14, piglets were killed and samples of intestinal contents were taken. Total counts of bacteria in the intestinal contents (jejunum, ileum, caecum, colon) were not significantly influenced. The pH value was significantly lower (P<0.05) only in duodenum of piglets receiving E. faecium EK13. There was a significant higher concentration of lactic acid (P<0.01) and propionic acid in the colon (P<0.001) of the EK13 group. Application of E. faecium EK13 did not influence the daily body weight gain significantly.

  13. Application of response surface methodology for optimizing arginine deiminase production medium for Enterococcus faecium sp. GR7.

    PubMed

    Kaur, Baljinder; Kaur, Rajinder

    2013-01-01

    Arginine metabolism in Enterococcus faecium sp. GR7 was enhanced via arginine deiminase pathway. Process parameters including fermentation media and environmental conditions were optimized using independent experiments and response surface methodology (central composite design). Fermentation media (EAPM) were optimized using independent experiments which resulted in 4-fold increase in arginine deiminase specific activity as compared to basal medium. To further enhance arginine deiminase activity in E. faecium sp. GR7 and biomass production including a five-level central composite design (CCD) was employed to study the interactive effect of three-process variables. Response surface methodology suggested a quadratic model which was further validated experimentally where it showed approximately 15-fold increase in arginine metabolism (in terms of arginine deiminase specific activity) over basal medium. By solving the regression equation and analyzing the response surface cartons, optimal concentrations of the media components (g/L) were determined as arginine 20.0; tryptone 15.0; lactose 10.0; K2HPO4 3.0; NaCl 1.0, MnSO4 0.6 mM; Tween 80 1%; pH 6.0 for achieving specific arginine deiminase activity of 4.6 IU/mG with concomitant biomass production of 12.1 mg/L. The model is significant as the coefficient of determination (R (2)) was 0.87 to 0.90 for all responses. Enhanced arginine deiminase yield from E. faecium, a GRAS lactic acid bacterial strain, is desirable to explore in vitro therapeutic potential of the arginine metabolizing E. faecium sp. GR7.

  14. Inhibition of Bacillus cereus Strains by Antimicrobial Metabolites from Lactobacillus johnsonii CRL1647 and Enterococcus faecium SM21.

    PubMed

    Soria, M Cecilia; Audisio, M Carina

    2014-12-01

    Bacillus cereus is an endospore-forming, Gram-positive bacterium able to cause foodborne diseases. Lactic acid bacteria (LAB) are known for their ability to synthesize organic acids and bacteriocins, but the potential of these compounds against B. cereus has been scarcely documented in food models. The present study has examined the effect of the metabolites produced by Lactobacillus johnsonii CRL1647 and Enterococcus faecium SM21 on the viability of select B. cereus strains. Furthermore, the effect of E. faecium SM21 metabolites against B. cereus strains has also been investigated on a rice food model. L. johnsonii CRL1647 produced 128 mmol/L of lactic acid, 38 mmol/L of acetic acid and 0.3 mmol/L of phenyl-lactic acid. These organic acids reduced the number of vegetative cells and spores of the B. cereus strains tested. However, the antagonistic effect disappeared at pH 6.5. On the other hand, E. faecium SM21 produced only lactic and acetic acid (24.5 and 12.2 mmol/L, respectively) and was able to inhibit both vegetative cells and spores of the B. cereus strains, at a final fermentation pH of 5.0 and at pH 6.5. This would indicate the action of other metabolites, different from organic acids, present in the cell-free supernatant. On cooked rice grains, the E. faecium SM21 bacteriocin(s) were tested against two B. cereus strains. Both of them were significantly affected within the first 4 h of contact; whereas B. cereus BAC1 cells recovered after 24 h, the effect on B. cereus 1 remained up to the end of the assay. The LAB studied may thus be considered to define future strategies for biological control of B. cereus.

  15. Combined administration of bacteriocin-producing, probiotic strain Enterococcus faecium CCM7420 with Eleutherococcus senticosus and their effect in rabbits.

    PubMed

    Simonová, M Pogány; Laukovtá, A; Chrastinová, L; Plachá, I; Strompfová, V; Cobanová, K; Formelová, Z; Chrenková, M

    2013-01-01

    The effect of Enterococcus faecium CCM7420 (EF) - enterocin-producing and probiotic strain of rabbit origin, Eleutherococcus senticosus extract (ES) and their combination (ES+EF) was determined on selected bacteria in faeces and caecum content, leukocytes phagocytosis, blood biochemistry and growth performance. Ninety-six weaned rabbits were divided into 3 experimental (ES, EF, ES+EF) and control group (CG). The rabbits in the groups ES and EF+ES were fed commercial diet enriched with E. senticosus extract (30 g/100 kg feed), rabbits in groups EF and CG were fed untreated diet. The rabbits in the EF and ES+EF groups were administered with an overnight culture of E. faecium CCM7420 strain (500 microl/animal/day into water, 109 CFU/ml). The treatment period lasted 21 days. The microbiological examinations in faecal samples confirmed the presence of E. faecium CCM7420 strain. In groups EF and ES+EF, the reduction of faecal coliforms, Pseudomonas-like sp., Clostridium-like sp. and S. aureus was recorded. Leucocyte phagocytosis significantly increased in all experimental groups (P < 0.0001) compared to CG. The lowest GPx values were measured in the ES+EF group. Higher total protein, triglycerides and calcium concentrations were detected in experimental groups compared to CG. The cholesterol concentration decreased in the ES group. The highest average daily gain was recorded in EF group; in ES+EF the better feed conversion ratio and no mortality was recorded. These results indicated that the dietary supplementation with the E. faecium CCM7420 and E. senticosus extract stimulate the leukocytes phagocytosis and reduces the potential pathogens in rabbits digestive tract without oxidative stress and improve the growth performance.

  16. β-Lactams Enhance Daptomycin Activity against Vancomycin-Resistant Enterococcus faecalis and Enterococcus faecium in In Vitro Pharmacokinetic/Pharmacodynamic Models

    PubMed Central

    Smith, Jordan R.; Barber, Katie E.; Raut, Animesh

    2015-01-01

    Enterococcus faecalis and Enterococcus faecium are frequently resistant to vancomycin and β-lactams. In enterococcal infections with reduced glycopeptide susceptibility, combination therapy is often administered. Our objective was to conduct pharmacokinetic/pharmacodynamic (PK/PD) models to evaluate β-lactam synergy with daptomycin (DAP) against resistant enterococci. One E. faecalis strain (R6981) and two E. faecium strains (R6370 and 8019) were evaluated. DAP MICs were obtained. All strains were evaluated for response to LL37, an antimicrobial peptide, in the presence and absence of ceftaroline (CPT), ertapenem (ERT), and ampicillin (AMP). After 96 h, in vitro models were run simulating 10 mg DAP/kg body weight/day, 600 mg CPT every 8 h (q8h), 2 g AMP q4h, and 1 g ERT q24h, both alone and in combination against all strains. DAP MICs were 2, 4, and 4 μg/ml for strains R6981, R6370, and 8019, respectively. PK/PD models demonstrated bactericidal activity with DAP-CPT, DAP-AMP, and DAP-ERT combinations against strain 8019 (P < 0.001 and log10 CFU/ml reduction of >2 compared to any single agent). Against strains R6981 and R6370, the DAP-AMP combination demonstrated enhancement against R6370 but not R6981, while the combinations of DAP-CPT and DAP-ERT were bactericidal, demonstrated enhancement, and were statistically superior to all other regimens at 96 h (P < 0.001) against both strains. CPT, ERT, and AMP similarly augmented LL37 killing against strain 8019. In strains R6981 and R6370, CPT and ERT aided LL37 more than AMP (P < 0.001). Compared to DAP alone, combination regimens provide better killing and prevent resistance. Clinical research involving DAP combinations is warranted. PMID:25753639

  17. Effect of dietary supplementation with a probiotic (Enterococcus faecium) on production performance, excreta microflora, ammonia emission, and nutrient utilization in ISA brown laying hens.

    PubMed

    Park, J W; Jeong, J S; Lee, S I; Kim, I H

    2016-12-01

    The ban on the use of antibiotics as growth promoters due to resistance issues has urged scientists to find alternatives to antibiotics. Entercoccus faecium is one of the probiotics which have been used as an alternative to antibiotics in the livestock industry. This study was conducted to evaluate the effect of probiotic (Enterococcus faecium DSM 7134) supplementation on production performance, feed intake, egg quality, excreta microflora, ammonia emission, and nutrient utilization in laying hens. A total of 288 ISA brown laying hens were used in a 27 wk feeding experiment and randomly assigned to 3 dietary treatments with 8 replicates of 12 birds each. The treatments were CON (basal diet), PB1 (basal diet + 0.005% E. faecium), and PB2 (basal diet + 0.01% E. faecium). Overall, our results demonstrated that E. faecium supplementation resulted in a significant increase in egg production, egg shell thickness, and nutrient digestibility (dry matter, nitrogen, and energy) in laying hens, and a significant reduction in fecal coliform counts as compared with CON. The shift of excreta fecal microbial composition by E. faecium supplementation was accompanied by increased nutrient retention and reduction in nutrient excretion, leading to improved nutrient digestibility and reduced excreta ammonia emission. Overall, E. faecium supplementation appears to have a beneficial effect in ISA brown laying hens and should be considered as a positive diet supplement to use in the industry.

  18. Enterococcus faecium biofilm formation: identification of major autolysin AtlAEfm, associated Acm surface localization, and AtlAEfm-independent extracellular DNA Release.

    PubMed

    Paganelli, Fernanda L; Willems, Rob J L; Jansen, Pamela; Hendrickx, Antoni; Zhang, Xinglin; Bonten, Marc J M; Leavis, Helen L

    2013-04-16

    Enterococcus faecium is an important multidrug-resistant nosocomial pathogen causing biofilm-mediated infections in patients with medical devices. Insight into E. faecium biofilm pathogenesis is pivotal for the development of new strategies to prevent and treat these infections. In several bacteria, a major autolysin is essential for extracellular DNA (eDNA) release in the biofilm matrix, contributing to biofilm attachment and stability. In this study, we identified and functionally characterized the major autolysin of E. faecium E1162 by a bioinformatic genome screen followed by insertional gene disruption of six putative autolysin genes. Insertional inactivation of locus tag EfmE1162_2692 resulted in resistance to lysis, reduced eDNA release, deficient cell attachment, decreased biofilm, decreased cell wall hydrolysis, and significant chaining compared to that of the wild type. Therefore, locus tag EfmE1162_2692 was considered the major autolysin in E. faecium and renamed atlAEfm. In addition, AtlAEfm was implicated in cell surface exposure of Acm, a virulence factor in E. faecium, and thereby facilitates binding to collagen types I and IV. This is a novel feature of enterococcal autolysins not described previously. Furthermore, we identified (and localized) autolysin-independent DNA release in E. faecium that contributes to cell-cell interactions in the atlAEfm mutant and is important for cell separation. In conclusion, AtlAEfm is the major autolysin in E. faecium and contributes to biofilm stability and Acm localization, making AtlAEfm a promising target for treatment of E. faecium biofilm-mediated infections. IMPORTANCE Nosocomial infections caused by Enterococcus faecium have rapidly increased, and treatment options have become more limited. This is due not only to increasing resistance to antibiotics but also to biofilm-associated infections. DNA is released in biofilm matrix via cell lysis, caused by autolysin, and acts as a matrix stabilizer. In this study

  19. Identification of vancomycin-susceptible major clones of clinical Enterococcus from Algeria.

    PubMed

    Bourafa, Nadjette; Abat, Cédric; Loucif, Lotfi; Olaitan, Abiola Olumuyiwa; Bentorki, Ahmed Aimen; Boutefnouchet, Nafissa; Rolain, Jean-Marc

    2016-09-01

    The main objectives of this study were to characterize clinical strains of Enterococcus spp. isolated from Algerian inpatients and outpatients, to investigate their susceptibility to antibiotics and to analyse their phylogenetic relatedness. A total of 85 non-duplicate Enterococcus spp. isolates collected between 2010 and 2013 from various clinical samples, including urine, vaginal swab, pus, blood and semen, from Algerian inpatients (n=62) and outpatients (n=23) were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS). Antibiotic susceptibility testing was performed using disk diffusion and Etest methods. Clonal relatedness was analysed using multilocus sequence typing (MLST). Enterococcus faecalis was the most predominant species (75.3%), followed by Enterococcus faecium (21.2%), Enterococcus gallinarum (2.4%) and Enterococcus casseliflavus (1.2%). High-level resistance to aminoglycosides was significantly more prevalent in hospitalized patients than in outpatients. None of the E. faecalis and E. faecium isolates were resistant to vancomycin. High genetic diversity was observed among the E. faecalis isolates, with the identification of a new clonal complex (CC256), as well as the detection of E. faecalis ST6 and E. faecium lineages ST17, ST18 and ST78 associated with hospital isolates. This is the first report of E. faecalis ST6 and E. faecium ST17 and ST18 in Algeria. Although acquired vancomycin resistance was not observed among the enterococcal strains, there is a continued need to monitor the level of antibiotic resistance among enterococci as well as the evolution of the E. faecalis/E. faecium ratio.

  20. Construction of improved temperature-sensitive and mobilizable vectors and their use for constructing mutations in the adhesin-encoding acm gene of poorly transformable clinical Enterococcus faecium strains.

    PubMed

    Nallapareddy, Sreedhar R; Singh, Kavindra V; Murray, Barbara E

    2006-01-01

    Inactivation by allelic exchange in clinical isolates of the emerging nosocomial pathogen Enterococcus faecium has been hindered by lack of efficient tools, and, in this study, transformation of clinical isolates was found to be particularly problematic. For this reason, a vector for allelic replacement (pTEX5500ts) was constructed that includes (i) the pWV01-based gram-positive repAts replication region, which is known to confer a high degree of temperature intolerance, (ii) Escherichia coli oriR from pUC18, (iii) two extended multiple-cloning sites located upstream and downstream of one of the marker genes for efficient cloning of flanking regions for double-crossover mutagenesis, (iv) transcriptional terminator sites to terminate undesired readthrough, and (v) a synthetic extended promoter region containing the cat gene for allelic exchange and a high-level gentamicin resistance gene, aph(2'')-Id, to distinguish double-crossover recombination, both of which are functional in gram-positive and gram-negative backgrounds. To demonstrate the functionality of this vector, the vector was used to construct an acm (encoding an adhesin to collagen from E. faecium) deletion mutant of a poorly transformable multidrug-resistant E. faecium endocarditis isolate, TX0082. The acm-deleted strain, TX6051 (TX0082Deltaacm), was shown to lack Acm on its surface, which resulted in the abolishment of the collagen adherence phenotype observed in TX0082. A mobilizable derivative (pTEX5501ts) that contains oriT of Tn916 to facilitate conjugative transfer from the transformable E. faecalis strain JH2Sm::Tn916 to E. faecium was also constructed. Using this vector, the acm gene of a nonelectroporable E. faecium wound isolate was successfully interrupted. Thus, pTEX5500ts and its mobilizable derivative demonstrated their roles as important tools by helping to create the first reported allelic replacement in E. faecium; the constructed this acm deletion mutant will be useful for assessing the

  1. Effects of Enterococcus faecium NCIMB 10415 as probiotic supplement on intestinal transport and barrier function of piglets.

    PubMed

    Lodemann, Ulrike; Hübener, Katrin; Jansen, Nicole; Martens, Holger

    2006-02-01

    Many studies report positive effects of probiotic supplementation on the performance and health of piglets. The intention of this study was to describe the effects of Enterococcus faecium NCIMB 10415 on the transport and barrier functions of pig small intestine to improve our understanding of the underlying mechanisms of this probiotic. Ussing chamber studies were conducted with isolated jejunal epithelia of piglets at the age of 14, 28, 35 and 56 days. Jejunal tissues of the control group were compared with epithelia of piglets that had received a diet supplemented with the probiotic Enterococcus faecium NCIMB 10415. Transport properties (absorption and secretion) of the epithelia were examined by mucosal addition of glucose or L-glutamine or by serosal addition of PGE2. Electrophysiology of the epithelia was continuously recorded and the change in short circuit current (Isc) was determined. Paracellular permeability was measured by measuring the flux rates of mannitol. The increase of Isc caused by mucosal addition of glucose was, at all glucose concentrations, higher in the probiotic group compared with the control group. However, the difference (up to 100% of the control) was not significant. The increase of Isc after the mucosal addition of L-glutamine (12mmol/l) was higher in the tissues of the probiotic group but did not reach significance. Serosal PGE2 induced a significantly higher increase of Isc in tissues of the probiotic group at the age of 28 days. No consistent differences were observed in mannitol transport rates between the feeding groups. Significant age-dependent alterations of absorptive and secretory properties of the jejunal epithelium were observed; these were independent of the treatment. A probiotic supplementation seems to influence transport properties of small intestine epithelium. The increased absorption of glucose could be interpreted as a positive effect for the animal.

  2. Improved detection of vanB2-containing enterococcus faecium with vancomycin susceptibility by Etest using oxgall supplementation.

    PubMed

    Grabsch, E A; Chua, K; Xie, S; Byrne, J; Ballard, S A; Ward, P B; Grayson, M L

    2008-06-01

    We have isolated a number of vanB-containing Enterococcus faecium isolates on bile esculin screening agar containing 6 mg/liter vancomycin, which on subsequent susceptibility testing using Etest have repeatedly demonstrated vancomycin MICs of faecium (n = 11), vancomycin-susceptible (van negative) E. faecium (n = 11), vancomycin-susceptible (van negative) E. faecalis (n = 11), and our LM-VRE (n = 23) isolates. After 48 h of incubation, both MHA-Oxg and BHIA-Oxg were 100% (34/34) sensitive and 100% (22/22) specific in the identification of vancomycin resistance. These findings suggest that supplementation of MHA or BHIA with 10 g/liter oxgall should be considered in laboratories where VRE detection protocols rely primarily on strain phenotype rather than early vanB gene detection by PCR.

  3. Effects of age and controlled oral dosing of Enterococcus faecium on epithelial properties in the piglet small intestine.

    PubMed

    Lodemann, U; Dillenseger, A; Aschenbach, J R; Martens, H

    2013-12-01

    Enterococcus faecium NCIMB 10415 is a licensed probiotic for piglets that has been shown to positively affect diarrhoea incidence and to act on transport properties and immunological parameters in the porcine intestine. The aim of the present study was to examine its effects on jejunal absorptive and secretory capacities around weaning. Furthermore, the possible involvement of heat shock proteins in the effects of probiotics on epithelial functions was investigated. A significant part of the probiotic was dosed orally to reduce the variability of intake of the probiotic. The piglets were randomly assigned to a control and a probiotic feeding group, the latter receiving 4.5×109 cfu/day of E. faecium directly into the mouth for 34 days starting after birth. Additionally, their feed was supplemented with the probiotic strain. Piglets were weaned at day 29 after birth. Ussing chamber studies were conducted with the mid-jejunum of piglets aged 14, 28, 31, 35 and 56 days. Changes in short-circuit current (ΔIsc) were measured after stimulation of Na+-coupled absorption with L-glutamine or glucose or with the secretagogue prostaglandin E2 (PGE2). The mRNA expression for SGLT1, CFTR and various heat shock proteins was determined. The transport properties changed significantly with age. The glucose-, L-glutamine- and PGE2-induced changes in Isc were highest at day 31 after birth. No significant differences between the feeding groups were observed. The mRNA of HSP60, HSC70, HSP70 and HSP90 was expressed in the jejunal tissues. The mRNA expression of HSC70 was higher and that of HSP60 was lower in the probiotic group. HSC70 expression increased with age. In conclusion, whereas age effects were observed on absorptive and secretory functions, controlled E. faecium dosing had no measurable effects on these functional parameters in this experimental setup. The possible role of heat shock proteins should be further evaluated.

  4. Healthcare-associated vancomycin resistant Enterococcus faecium infections in the Mansoura University Hospitals intensive care units, Egypt.

    PubMed

    Moemen, Dalia; Tawfeek, Doaa; Badawy, Wafaa

    2015-01-01

    Vancomycin resistant Enterococcus faecium (VREF) ia an emerging and challenging nosocomial pathogen. This study aimed to determine the prevalence, risk factors and clonal relationships between different VREF isolates in the intensive care units (ICUs) of the university hospitals in our geographic location. This prospective study was conducted from July, 2012 until September, 2013 on 781 patients who were admitted to the ICUs of the Mansoura University Hospitals (MUHs), and fulfilled the healthcare-associated infection (HAI) criteria. Susceptibility testing was determined using the disk diffusion method. The clonal relationships were evaluated with pulsed field gel electrophoresis (PFGE). Out of 52 E. faecium isolates, 12 (23.1%) were vancomycin resistant. The significant risk factors for the VREF infections were: transfer to the ICU from a ward, renal failure, an extended ICU stay and use of third-generation cephalosporins, gentamicin, or ciprofloxacin. PFGE with the 12 isolates showed 9 different patterns; 3 belonged to the same pulsotype and another 2 carried a second pulsotypes. The similar pulsotypes isolates were isolated from ICUs of one hospital (EICUs); however, all of the isolates from the other ICUs had different patterns. Infection control policy, in conjunction with antibiotic stewardship, is important to combat VREF transmission in these high-risk patients.

  5. Isolation and purification of two bacteriocins 3D produced by Enterococcus faecium with inhibitory activity against Listeria monocytogenes.

    PubMed

    Bayoub, Kaoutar; Mardad, Ilham; Ammar, Emna; Serrano, Aurelio; Soukri, Abdelaziz

    2011-02-01

    Strain 3D, isolated from fermented traditional Moroccan dairy product, and identified as Enterococcus faecium, was studied for its capability to produce two bacteriocins acting against Listeria monocytogenes. Bacteriocins 3 Da and 3Db were heat stable inactivated by proteinase K, pepsin, and trypsin but not when treated with catalase. The evidenced bacteriocins were stable in a wide pH range from 2 to 11 and bactericidal activity was kept during storage at 4°C. However, the combination of temperature and pH exhibited a stability of the bacteriocins. RP-HPLC purification of the anti-microbial compounds shows two active fractions eluted at 16 and 30.5 min, respectively. Mass spectrometry analysis showed that E. faecium 3D produce two bacteriocins Enterocin 3 Da (3893.080 Da) and Enterocin 3Db (4203.350 Da). This strain is food-grade organism and its bacteriocins were heat-stable peptides at basic, neutral, and acid pH: such bacteriocins may be of interest as food preservatives.

  6. Emergence of high ampicillin-resistant Enterococcus faecium isolates in a kidney transplant ward: role of antibiotic pressure and cross transmission.

    PubMed

    Maillard, Olivier; Corvec, Stéphane; Dantal, Jacques; Reynaud, Alain; Lucet, Jean-Christophe; Bémer, Pascale; Lepelletier, Didier

    2010-06-01

    The epidemiology of patients associated with ampicillin-resistant Enterococcus faecium (ARE) was investigated by combining both clinical approach and molecular analysis in a kidney transplant patient's ward. A case-control study was performed to identify risk factors for ARE by matching each patient with ARE with two control patients without any isolated E. faecium strain. ARE isolates were characterized by pulsed-field gel electrophoresis. From June 2004 to May 2006, 18 cases with clinical ARE samples were detected and compared with 35 control patients. By univariate analysis, recurrent urinary tract infections (UTIs) (odds ratio [OR], 4.9; 95% confidence interval [CI], 1.0-25.6), mean number of hospitalization days in the last year (p < 0.003), pyelonephritis or UTI (OR, 9.6; 95% CI, 2.2-46.1), oral third-generation cephalosporin use (OR, 12.42; 95% CI, 2.04-109.1), and fluoroquinolone use (OR, 4.4; 95% CI, 1.1-18.2) were significantly associated with ARE urinary tract colonization. By conditional logistic regression, hospitalization >21 days within 1 year (adjusted OR [aOR], 6.9; 95% CI, 1.0-46.5), recent medical history of pyelonephritis or UTI (aOR, 8.6; 95% CI, 1.5-49.1), and prior oral third-generation cephalosporin use (aOR, 13.1; 95% CI, 1.2-142.6) were identified as independent factors associated with ARE urinary tract colonization. Genotyping revealed a heterogeneous epidemiological situation with two major clones in patients hospitalized in successive rooms and 10 different single pulsotypes. Emergence of highly resistant enterococcal strains is a collateral damage from antibiotic prescription and represents a potential source of patient-to-patient transmission. Combining epidemiological approach and molecular analysis is a powerful tool to delineate mechanisms of emerging resistance. Improving our knowledge on ARE emergence in high antibiotic pressure hospital wards is a key factor to better control these colonizations/infections and to prevent the

  7. Molecular characterization of resistance, virulence and clonality in vancomycin-resistant Enterococcus faecium and Enterococcus faecalis: A hospital-based study in Beijing, China.

    PubMed

    Yang, Jing-xian; Li, Tong; Ning, Yong-zhong; Shao, Dong-hua; Liu, Jing; Wang, Shu-qin; Liang, Guo-wei

    2015-07-01

    The incidence of vancomycin-resistant enterococcus (VRE) in China is increasing, the molecular epidemiology of VRE in China is only partly known. This study was conducted to assess the molecular characterization of resistance, virulence and clonality of 69 vancomycin-resistant Enterococcus faecium (VREfm) and seven vancomycin-resistant Enterococcus faecalis (VREfs) isolates obtained from a Chinese hospital between July 2011 and July 2013. The glycopeptide resistance genes (VanA and VanB) were screened by multiplex PCR. The presence of five putative virulence genes (esp, gelE, asa1, hyl and cylA) were evaluated by another multiplex PCR. Multilocus sequence typing (MLST) scheme was used to assess the clonality. All 76 VRE isolates exhibited VanA phenotype and harbored VanA gene. Esp was the only gene detected both in VREfm and VREfs strains, accounting for 89.9% and 42.9%, respectively. The hyl gene was merely positive in 27.5% of VREfm strains. MLST analysis demonstrated three STs (ST6, ST4 and ST470) in VREfs and twelve STs (ST78, ST571, ST17, ST564, ST389, ST18, ST547, ST341, ST414, ST343, ST262 and ST203) in VREfm, which were all designated as CC17 by eBURST algorithm. An outbreak of VREfm belonging to ST571 was found to happen within the neurology ward in this hospital. To our knowledge, this is the first report of ST6 (CC2) VREfs strains in China and the first outbreak report of VREfm strains belonging to ST571 around the world. Our data could offer important information for understanding the molecular features of VRE in China.

  8. Effect of subtherapeutic antimicrobials on genetic diversity of Enterococcus faecium from chickens.

    PubMed

    Jackson, Charlene R; Debnam, Antoinette L; Avellaneda, Gloria E; Barrett, John B; Hofacre, Charles L

    2006-03-01

    The effect of growth promotants (bacitracin, virginiamycin, and flavomycin) on the genetic population of Enterococcusfaecium isolated from a commercially integrated poultry farm was examined. A total of 551 E. faecium were isolated from chick boxliners (n=16), litter (n=334), feed (n=67), and carcass rinse (n=134) samples from four chicken houses. Two houses on the farm were control houses and did not use any antimicrobials while two other houses on the farm used flavomycin, virginiamycin, and bacitracin during six different chicken grow outs. BOX-PCR and pulsed-field gel electrophoresis (PFGE) results indicated that E. faecium strains had a high degree of genetic diversity as overall clustering was independent of source, house, or grow out. Similarity of > or =60% for the majority of BOX-PCR genogroups and > or =80% for the majority of PFGE genogroups was observed for a subset of carcass rinse samples (n=45) examined. Seventy-nine percent (19/24) of isolates in BOX-PCR genogroup 2 also clustered in PFGE genogroup 2, although no association between the isolates and house or grow out was observed. These results suggest that E. faecium from chicken are genetically diverse and that growth-promoting antimicrobials do not affect the genetic population of E. faecium.

  9. Use of bacteriocin-producing, probiotic strain Enterococcus faecium AL41 to control intestinal microbiota in farm ostriches.

    PubMed

    Lauková, A; Kandričáková, A; Ščerbová, J

    2015-06-01

    Probiotic enterococci can produce bacteriocins. Enterococcus faecium AL41 is an Enterocin M-producing, probiotic strain which has previously shown beneficial effect in broiler chickens. In this study, it was used to control intestinal microbiota in farm ostriches in a 42-day experiment with an experimental group (EG, 40 ostriches) and a control group (CG, 46). In addition to feed mixture, the ostriches in EG received Ent. faecium AL41 (10(9) CFU ml(-1); by rifampicin-marked variant) 400 μl per animal per day in their drinking water for 21 days. Sampling was carried out at the start of the experiment (at day 0/1), at day 21 (after 21 days of AL41 application) and at day 42 (21 days after AL41 cessation). Faeces (mixture, n = 6) were treated using the standard microbiological dilution method and cultivated on selective media (ISO). The highest count of AL41 was found at day 42. Its identity was confirmed with PCR and Maldi-Tof. The ostriches were free of Salmonella and Campylobacter cells. At day 21, antimicrobial effect was demonstrated by significant reduction in coagulase-positive and negative staphylococci in EG compared to CG (P < 0·001) and coliforms, Enterobacteria and Pseudomonas-like bacteria (P < 0·001). We conclude that AL41 can be used to control intestinal microbiota in farm ostriches. Significance and impact of the study: Ostriches are excellent for high intensity farming in a wide range of climates, requiring only limited space and giving high yields per hectare. They are reared mainly for their meat. Although adult birds possess quite good immunity, young birds can be threatened by spoilage bacteria, especially when they are transferred from the nests to the farm area. Based on our previous results related to the beneficial effect of bacteriocin-producing, probiotic strain Enterococcus faecium AL41 in poultry or rabbits, we decided to test its ability to control intestinal microbiota in farming ostriches which has never been tested previously.

  10. Importance of two Enterococcus faecium loci encoding Gls-like proteins for in vitro bile salts stress response and virulence.

    PubMed

    Choudhury, Tina; Singh, Kavindra V; Sillanpää, Jouko; Nallapareddy, Sreedhar R; Murray, Barbara E

    2011-04-15

    General stress proteins, Gls24 and GlsB, were previously shown to be involved in bile salts resistance of Enterococcus faecalis and in virulence. Here, we identified 2 gene clusters in Enterococcus faecium each encoding a homolog of Gls24 (Gls33 and Gls20; designated on the basis of their predicted sizes) and of GlsB (GlsB and GlsB1). The sequences of the gls33 and gls20 gene clusters from available genomes indicate distinct lineages, with those of hospital-associated CC17 isolates differing from non-CC17 by ∼7% and ∼3.5%, respectively. Deletion of an individual locus did not have a significant effect on virulence in a mouse peritonitis model, whereas a double-deletion mutant was highly attenuated (P<.004) versus wild-type. However, mutants lacking either gls33-glsB, gls20-glsB1, or both all exhibited increased sensitivity to bile salts. These results suggest that gls-encoded loci may be important for adaptation to the intestinal environment, in addition to being important for virulence functions.

  11. Inactivation of Salmonella, Listeria monocytogenes and Enterococcus faecium NRRL B-2354 in a selection of low moisture foods.

    PubMed

    Rachon, Grzegorz; Peñaloza, Walter; Gibbs, Paul A

    2016-08-16

    The aims of this study were to obtain data on survival and heat resistance of cocktails of Salmonella, Listeria monocytogenes and the surrogate Enterococcus faecium (NRRL B-2354) in four low moisture foods (confectionery formulation, chicken meat powder, pet food and savoury seasoning) during storage before processing. Inoculated samples were stored at 16°C and cell viability examined at day 0, 3, 7 and 21. At each time point, the heat resistance at 80°C was determined. The purpose was to determine a suitable storage time of inoculated foods that can be applied in heat resistance studies or process validations with similar cell viability and heat resistance characteristics. The main inactivation study was carried out within 7days after inoculation, the heat resistance of each bacterial cocktail was evaluated in each low moisture food heated in thermal cells exposed to temperatures between 70 and 140°C. The Weibull model and the first order kinetics (D-value) were used to express inactivation data and calculate the heating time to achieve 5 log reduction at each temperature. Results showed that the pathogens Salmonella and L. monocytogenes and the surrogate E. faecium NRRL B-2354, can survive well (maximum reduction <0.8 log) in low moisture foods maintained at 16°C, as simulation of warehouse raw material storage in winter and before processing. The D80 value of the pathogens and surrogate did not significantly change during the 21day storage (p>0.05). The inactivation kinetics of the pathogens and surrogate at temperatures between 70 and 140°C, were different between each organism and product. E. faecium NRRL B-2354 was a suitable Salmonella surrogate for three of the low moisture foods studied, but not for the sugar-containing confectionery formulation. Heating low moisture food in moisture-tight environments (thermal cells) to 111.2, 105.3 or 111.8°C can inactivate 5 log of Salmonella, L. monocytogenes or E. faecium NRRL B-2354 respectively.

  12. Dietary Enterococcus faecium NCIMB 10415 and Zinc Oxide Stimulate Immune Reactions to Trivalent Influenza Vaccination in Pigs but Do Not Affect Virological Response upon Challenge Infection

    PubMed Central

    Wang, Zhenya; Burwinkel, Michael; Chai, Weidong; Lange, Elke; Blohm, Ulrike; Breithaupt, Angele; Hoffmann, Bernd; Twardziok, Sven; Rieger, Juliane; Janczyk, Pawel; Pieper, Robert; Osterrieder, Nikolaus

    2014-01-01

    Swine influenza viruses (SIV) regularly cause significant disease in pigs worldwide. Since there is no causative treatment of SIV, we tested if probiotic Enterococcus (E.) faecium NCIMB 10415 or zinc (Zn) oxide as feed supplements provide beneficial effects upon SIV infection in piglets. Seventy-two weaned piglets were fed three different diets containing either E. faecium or different levels of Zn (2500 ppm, Znhigh; 50 ppm, Znlow). Half of the piglets were vaccinated intramuscularly (VAC) twice with an inactivated trivalent SIV vaccine, while all piglets were then infected intranasally with H3N2 SIV. Significantly higher weekly weight gains were observed in the E. faecium group before virus infection, and piglets in Znhigh and E. faecium groups gained weight after infection while those in the control group (Znlow) lost weight. Using ELISA, we found significantly higher H3N2-specific antibody levels in the E. faecium+VAC group 2 days before and at the day of challenge infection as well as at 4 and 6 days after challenge infection. Higher hemagglutination inhibition (HI) titers were also observed in the Znhigh+VAC and E. faecium+VAC groups at 0, 1 and 4 days after infection. However, there were no significant differences in virus shedding and lung lesions between the dietary groups. Using flow cytometry analysis significantly higher activated T helper cells and cytotoxic T lymphocyte percentages in the PBMCs were detected in the Znhigh and E. faecium groups at single time points after infection compared to the Znlow control group, but no prolonged effect was found. In the BAL cells no influence of dietary supplementation on immune cell percentages could be detected. Our results suggest that feeding high doses of zinc oxide and particularly E. faecium could beneficially influence humoral immune responses after vaccination and recovery from SIV infection, but not affect virus shedding and lung pathology. PMID:24489827

  13. Behavior of Listeria monocytogenes in a multi-species biofilm with Enterococcus faecalis and Enterococcus faecium and control through sanitation procedures.

    PubMed

    da Silva Fernandes, Meg; Kabuki, Dirce Yorika; Kuaye, Arnaldo Yoshiteru

    2015-05-04

    The formation of mono-species biofilm (Listeria monocytogenes) and multi-species biofilms (Enterococcus faecium, Enterococcus faecalis, and L. monocytogenes) was evaluated. In addition, the effectiveness of sanitation procedures for the control of the multi-species biofilm also was evaluated. The biofilms were grown on stainless steel coupons at various incubation temperatures (7, 25 and 39°C) and contact times (0, 1, 2, 4, 6 and 8 days). In all tests, at 7°C, the microbial counts were below 0.4 log CFU/cm(2) and not characteristic of biofilms. In mono-species biofilm, the counts of L. monocytogenes after 8 days of contact were 4.1 and 2.8 log CFU/cm(2) at 25 and 39°C, respectively. In the multi-species biofilms, Enterococcus spp. were present at counts of 8 log CFU/cm(2) at 25 and 39°C after 8 days of contact. However, the L. monocytogenes in multi-species biofilms was significantly affected by the presence of Enterococcus spp. and by temperature. At 25°C, the growth of L. monocytogenes biofilms was favored in multi-species cultures, with counts above 6 log CFU/cm(2) after 8 days of contact. In contrast, at 39°C, a negative effect was observed for L. monocytogenes biofilm growth in mixed cultures, with a significant reduction in counts over time and values below 0.4 log CFU/cm(2) starting at day 4. Anionic tensioactive cleaning complemented with another procedure (acid cleaning, disinfection or acid cleaning+disinfection) eliminated the multi-species biofilms under all conditions tested (counts of all micro-organisms<0.4 log CFU/cm(2)). Peracetic acid was the most effective disinfectant, eliminating the multi-species biofilms under all tested conditions (counts of the all microorganisms <0.4 log CFU/cm(2)). In contrast, biguanide was the least effective disinfectant, failing to eliminate biofilms under all the test conditions.

  14. Disruption of an Enterococcus faecium Species-Specific Gene, a Homologue of Acquired Macrolide Resistance Genes of Staphylococci, Is Associated with an Increase in Macrolide Susceptibility

    PubMed Central

    Singh, Kavindra V.; Malathum, Kumthorn; Murray, Barbara E.

    2001-01-01

    The complete sequence (1,479 nucleotides) of msrC, part of which was recently reported by others using a different strain, was determined. This gene was found in 233 of 233 isolates of Enterococcus faecium but in none of 265 other enterococci. Disruption of msrC was associated with a two- to eightfold decrease in MICs of erythromycin azithromycin, tylosin, and quinupristin, suggesting that it may explain in part the apparent greater intrinsic resistance to macrolides of isolates of E. faecium relative to many streptococci. This endogenous, species-specific gene of E. faecium is 53% identical to msr(A), suggesting that it may be a remote progenitor of the acquired macrolide resistance gene found in some isolates of staphylococci. PMID:11120975

  15. Purification and characterization of enterocin MC13 produced by a potential aquaculture probiont Enterococcus faecium MC13 isolated from the gut of Mugil cephalus.

    PubMed

    Satish Kumar, R; Kanmani, P; Yuvaraj, N; Paari, K A; Pattukumar, V; Arul, V

    2011-12-01

    A bacteriocin producer strain MC13 was isolated from the gut of Mugil cephalus (grey mullet) and identified as Enterococcus faecium. The bacteriocin of E. faecium MC13 was purified to homogeneity, as confirmed by Tricine sodium dodecyl sulphate - polyacrylamide gel electrophoresis (SDS-PAGE). Reverse-phase high-performance liquid chromatography (HPLC) analysis showed a single active fraction eluted at 26 min, and matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry analysis showed the molecular mass to be 2.148 kDa. The clear zone in native PAGE corresponding to enterocin MC13 band further substantiated its molecular mass. A dialyzed sample (semicrude preparation) of enterocin MC13 was broad spectrum in its action and inhibited important seafood-borne pathogens: Listeria monocytogenes , Vibrio parahaemolyticus, and Vibrio vulnificus. This antibacterial substance was sensitive to proteolytic enzymes: trypsin, protease, and chymotrypsin but insensitive to catalase and lipase, confirming that inhibition was due to the proteinaceous molecule, i.e., bacteriocin, and not due to hydrogen peroxide. Enterocin MC13 tolerated heat treatment (up to 90 °C for 20 min). Enterococcus faecium MC13 was effective in bile salt tolerance, acid tolerance, and adhesion to the HT-29 cell line. These properties reveal the potential of E. faecium MC13 to be a probiotic bacterium. Enterococcus faecium MC13 could be used as potential fish probiotic against pathogens such as V. parahaemolyticus, Vibrio harveyi, and Aeromonas hydrophila in fisheries. Also, this could be a valuable seafood biopreservative against L. monocytogenes.

  16. Aminoglycoside-Streptothricin Resistance Gene Cluster aadE–sat4–aphA-3 Disseminated among Multiresistant Isolates of Enterococcus faecium

    PubMed Central

    Werner, Guido; Hildebrandt, Bianca; Witte, Wolfgang

    2001-01-01

    Seventy-two Enterococcus faecium isolates of different origins highly resistant to nourseothricin and streptomycin were studied. Sequencing of a genomic fragment from two isolates identified a gene cluster, aadE–sat4–aphA-3, which has been isolated recently in staphylococci and Campylobacter coli. Patterns of digested PCR products of aadE–sat4–aphA-3 were identical for all isolates. PMID:11600397

  17. Influence of a probiotic strain of Enterococcus faecium on Salmonella enterica serovar Typhimurium DT104 infection in a porcine animal infection model.

    PubMed

    Szabó, István; Wieler, Lothar H; Tedin, Karsten; Scharek-Tedin, Lydia; Taras, David; Hensel, Andreas; Appel, Bernd; Nöckler, Karsten

    2009-05-01

    The beneficial effects of probiotic Enterococcus spp. in different hosts, such as mice and humans, have previously been reported in several studies. However, studies of large domestic animals, as well as challenge studies with pathogenic microorganisms, are very rare. Here, we investigated the influence of oral treatment of pigs with the probiotic bacterium Enterococcus faecium NCIMB 10415 on Salmonella enterica serovar Typhimurium DT104 infections in weaning piglets. Clinical symptoms, fecal excretion, the organ distribution of Salmonella, and the humoral immune response (immunoglobulin G [IgG], IgM, and IgA levels) in serum were examined. A pool of 89 piglets was randomly divided into probiotic and control groups. The probiotic group received a feed supplement containing E. faecium starting on day 14 postpartum prior to challenge with Salmonella serovar Typhimurium DT104 at 28 days postpartum. After challenge with Salmonella serovar Typhimurium DT104, piglets in both groups showed no severe clinical signs of salmonellosis. However, fecal excretion and colonization of Salmonella in organs were significantly greater in piglets fed E. faecium. Likewise, the humoral immune response against Salmonella (serum IgM and IgA levels) was significantly greater in the probiotic group animals than in control animals. The results of this study suggest that E. faecium NCIMB 10415 treatment enhanced the course of infection in weaning piglets challenged with Salmonella serovar Typhimurium DT104. However, the probiotic treatment also appeared to result in greater production of specific antibodies against Salmonella serovar Typhimurium DT104.

  18. Influence of a Probiotic Strain of Enterococcus faecium on Salmonella enterica Serovar Typhimurium DT104 Infection in a Porcine Animal Infection Model▿

    PubMed Central

    Szabó, István; Wieler, Lothar H.; Tedin, Karsten; Scharek-Tedin, Lydia; Taras, David; Hensel, Andreas; Appel, Bernd; Nöckler, Karsten

    2009-01-01

    The beneficial effects of probiotic Enterococcus spp. in different hosts, such as mice and humans, have previously been reported in several studies. However, studies of large domestic animals, as well as challenge studies with pathogenic microorganisms, are very rare. Here, we investigated the influence of oral treatment of pigs with the probiotic bacterium Enterococcus faecium NCIMB 10415 on Salmonella enterica serovar Typhimurium DT104 infections in weaning piglets. Clinical symptoms, fecal excretion, the organ distribution of Salmonella, and the humoral immune response (immunoglobulin G [IgG], IgM, and IgA levels) in serum were examined. A pool of 89 piglets was randomly divided into probiotic and control groups. The probiotic group received a feed supplement containing E. faecium starting on day 14 postpartum prior to challenge with Salmonella serovar Typhimurium DT104 at 28 days postpartum. After challenge with Salmonella serovar Typhimurium DT104, piglets in both groups showed no severe clinical signs of salmonellosis. However, fecal excretion and colonization of Salmonella in organs were significantly greater in piglets fed E. faecium. Likewise, the humoral immune response against Salmonella (serum IgM and IgA levels) was significantly greater in the probiotic group animals than in control animals. The results of this study suggest that E. faecium NCIMB 10415 treatment enhanced the course of infection in weaning piglets challenged with Salmonella serovar Typhimurium DT104. However, the probiotic treatment also appeared to result in greater production of specific antibodies against Salmonella serovar Typhimurium DT104. PMID:19270131

  19. Clinical isolates of Enterococcus faecium exhibit strain-specific collagen binding mediated by Acm, a new member of the MSCRAMM family.

    PubMed

    Nallapareddy, Sreedhar R; Weinstock, George M; Murray, Barbara E

    2003-03-01

    A collagen-binding adhesin of Enterococcus faecium, Acm, was identified. Acm shows 62% similarity to the Staphylococcus aureus collagen adhesin Cna over the entire protein and is more similar to Cna (60% and 75% similarity with Cna A and B domains respectively) than to the Enterococcus faecalis collagen-binding adhesin, Ace, which shares homology with Acm only in the A domain. Despite the detection of acm in 32 out of 32 E. faecium isolates, only 11 of these (all clinical isolates, including four vancomycin-resistant endocarditis isolates and seven other isolates) exhibited binding to collagen type I (CI). Although acm from three CI-binding vancomycin-resistant E. faecium clinical isolates showed 100% identity, analysis of acm genes and their promoter regions from six non-CI-binding strains identified deletions or mutations that introduced stop codons and/or IS elements within the gene or the promoter region in five out of six strains, suggesting that the presence of an intact functional acm gene is necessary for binding of E. faecium strains to CI. Recombinant Acm A domain showed specific and concentration-dependent binding to collagen, and this protein competed with E. faecium binding to immobilized CI. Consistent with the adherence phenotype and sequence data, probing with Acm-specific IgGs purified from anti-recombinant Acm A polyclonal rabbit serum confirmed the surface expression of Acm in three out of three collagen-binding clinical isolates of E. faecium tested, but in none of the strains with a non-functional pseudo acm gene. Introduction of a functional acm gene into two non-CI-binding natural acm mutant strains conferred a CI-binding phenotype, further confirming that native Acm is sufficient for the binding of E. faecium to CI. These results demonstrate that acm, which encodes a potential virulence factor, is functional only in certain infection-derived clinical isolates of E. faecium, and suggest that Acm is the primary adhesin responsible for the

  20. Detection of a New cfr-Like Gene, cfr(B), in Enterococcus faecium Isolates Recovered from Human Specimens in the United States as Part of the SENTRY Antimicrobial Surveillance Program

    PubMed Central

    Deshpande, Lalitagauri M.; Ashcraft, Deborah S.; Kahn, Heather P.; Pankey, George; Jones, Ronald N.; Farrell, David J.

    2015-01-01

    Two linezolid-resistant Enterococcus faecium isolates (MICs, 8 μg/ml) from unique patients of a medical center in New Orleans were included in this study. Isolates were initially investigated for the presence of mutations in the V domain of 23S rRNA genes and L3, L4, and L22 ribosomal proteins, as well as cfr. Isolates were subjected to pulsed-field gel electrophoresis (just one band difference), and one representative strain was submitted to whole-genome sequencing. Gene location was also determined by hybridization, and cfr genes were cloned and expressed in a Staphylococcus aureus background. The two isolates had one out of six 23S rRNA alleles mutated (G2576T), had wild-type L3, L4, and L22 sequences, and were positive for a cfr-like gene. The sequence of the protein encoded by the cfr-like gene was most similar (99.7%) to that found in Peptoclostridium difficile, which shared only 74.9% amino acid identity with the proteins encoded by genes previously identified in staphylococci and non-faecium enterococci and was, therefore, denominated Cfr(B). When expressed in S. aureus, the protein conferred a resistance profile similar to that of Cfr. Two copies of cfr(B) were chromosomally located and embedded in a Tn6218 similar to the cfr-carrying transposon described in P. difficile. This study reports the first detection of cfr genes in E. faecium clinical isolates in the United States and characterization of a new cfr variant, cfr(B). cfr(B) has been observed in mobile genetic elements in E. faecium and P. difficile, suggesting potential for dissemination. However, further analysis is necessary to access the resistance levels conferred by cfr(B) when expressed in enterococci. PMID:26248384

  1. Emergence of daptomycin non-susceptibility in colonizing vancomycin-resistant Enterococcus faecium isolates during daptomycin therapy.

    PubMed

    Lellek, Heinrich; Franke, Gefion C; Ruckert, Carolin; Wolters, Manuel; Wolschke, Christiane; Christner, Martin; Büttner, Henning; Alawi, Malik; Kröger, Nicolaus; Rohde, Holger

    2015-12-01

    Infections due to vancomycin-resistant enterococci (VRE) are of significant importance in high-risk populations, and daptomycin is a bactericidal antibiotic to treat multidrug-resistant VRE in these patients. The emergence of daptomycin non-susceptibility invasive VRE during daptomycin therapy is a major clinical issue. Here the hypothesis was tested that systemic daptomycin therapy also induces the emergence of daptomycin non-susceptible (DNS-) isolates in colonizing VRE populations. 11 vancomycin-resistant Enterococcus faecium strain pairs recovered from rectal swabs were available for analysis. All initial isolates exhibited daptomycin MICs within the wild type MIC distribution of E. faecium (MIC≤4 mg/L). In follow-up isolates from five patients a 4-16-fold daptomycin MIC increase was detected. All patients carrying DNS-VRE received daptomycin (14-28 days) at 4 mg/kg body weight, while two patients in whom no DNS-VRE emerged were only treated with daptomycin for 1 and 4 days, respectively. Comparative whole genome sequencing identified DNS-VRE-specific single nucleotide polymorphisms (SNP), including mutations in cardiolipin synthase (Cls), and additional SNPs in independent genes potentially relevant for the DNS phenotype. Mutations within cls were also identified in three additional, colonizing DNS-VRE. Of these, at least one strain was transmitted within the hospital. In none of the VRE isolates tested, pre-existing or de novo mutations in the liaFSR operon were detected. This is the first report documenting the emergence of DNS-VRE in colonizing strains during daptomycin treatment, putting the patient at risk for subsequent DNS-VRE infections and priming the spread of DNS-VRE within the hospital environment.

  2. AsrR is an oxidative stress sensing regulator modulating Enterococcus faecium opportunistic traits, antimicrobial resistance, and pathogenicity.

    PubMed

    Lebreton, François; van Schaik, Willem; Sanguinetti, Maurizio; Posteraro, Brunella; Torelli, Riccardo; Le Bras, Florian; Verneuil, Nicolas; Zhang, Xinglin; Giard, Jean-Christophe; Dhalluin, Anne; Willems, Rob J L; Leclercq, Roland; Cattoir, Vincent

    2012-01-01

    Oxidative stress serves as an important host/environmental signal that triggers a wide range of responses in microorganisms. Here, we identified an oxidative stress sensor and response regulator in the important multidrug-resistant nosocomial pathogen Enterococcus faecium belonging to the MarR family and called AsrR (antibiotic and stress response regulator). The AsrR regulator used cysteine oxidation to sense the hydrogen peroxide which results in its dissociation to promoter DNA. Transcriptome analysis showed that the AsrR regulon was composed of 181 genes, including representing functionally diverse groups involved in pathogenesis, antibiotic and antimicrobial peptide resistance, oxidative stress, and adaptive responses. Consistent with the upregulated expression of the pbp5 gene, encoding a low-affinity penicillin-binding protein, the asrR null mutant was found to be more resistant to β-lactam antibiotics. Deletion of asrR markedly decreased the bactericidal activity of ampicillin and vancomycin, which are both commonly used to treat infections due to enterococci, and also led to over-expression of two major adhesins, acm and ecbA, which resulted in enhanced in vitro adhesion to human intestinal cells. Additional pathogenic traits were also reinforced in the asrR null mutant including greater capacity than the parental strain to form biofilm in vitro and greater persistance in Galleria mellonella colonization and mouse systemic infection models. Despite overexpression of oxidative stress-response genes, deletion of asrR was associated with a decreased oxidative stress resistance in vitro, which correlated with a reduced resistance to phagocytic killing by murine macrophages. Interestingly, both strains showed similar amounts of intracellular reactive oxygen species. Finally, we observed a mutator phenotype and enhanced DNA transfer frequencies in the asrR deleted strain. These data indicate that AsrR plays a major role in antimicrobial resistance and

  3. AsrR Is an Oxidative Stress Sensing Regulator Modulating Enterococcus faecium Opportunistic Traits, Antimicrobial Resistance, and Pathogenicity

    PubMed Central

    Lebreton, François; van Schaik, Willem; Sanguinetti, Maurizio; Posteraro, Brunella; Torelli, Riccardo; Le Bras, Florian; Verneuil, Nicolas; Zhang, Xinglin; Giard, Jean-Christophe; Dhalluin, Anne; Willems, Rob J. L.; Leclercq, Roland; Cattoir, Vincent

    2012-01-01

    Oxidative stress serves as an important host/environmental signal that triggers a wide range of responses in microorganisms. Here, we identified an oxidative stress sensor and response regulator in the important multidrug-resistant nosocomial pathogen Enterococcus faecium belonging to the MarR family and called AsrR (antibiotic and stress response regulator). The AsrR regulator used cysteine oxidation to sense the hydrogen peroxide which results in its dissociation to promoter DNA. Transcriptome analysis showed that the AsrR regulon was composed of 181 genes, including representing functionally diverse groups involved in pathogenesis, antibiotic and antimicrobial peptide resistance, oxidative stress, and adaptive responses. Consistent with the upregulated expression of the pbp5 gene, encoding a low-affinity penicillin-binding protein, the asrR null mutant was found to be more resistant to β-lactam antibiotics. Deletion of asrR markedly decreased the bactericidal activity of ampicillin and vancomycin, which are both commonly used to treat infections due to enterococci, and also led to over-expression of two major adhesins, acm and ecbA, which resulted in enhanced in vitro adhesion to human intestinal cells. Additional pathogenic traits were also reinforced in the asrR null mutant including greater capacity than the parental strain to form biofilm in vitro and greater persistance in Galleria mellonella colonization and mouse systemic infection models. Despite overexpression of oxidative stress-response genes, deletion of asrR was associated with a decreased oxidative stress resistance in vitro, which correlated with a reduced resistance to phagocytic killing by murine macrophages. Interestingly, both strains showed similar amounts of intracellular reactive oxygen species. Finally, we observed a mutator phenotype and enhanced DNA transfer frequencies in the asrR deleted strain. These data indicate that AsrR plays a major role in antimicrobial resistance and

  4. Effects of two novel amino acid substitutions on the penicillin binding properties of the PBP5 C‑terminal from Enterococcus faecium.

    PubMed

    Zhou, Chengjiang; Niu, Haiying; Yu, Hui; Zhou, Lishe; Wang, Zhanli

    2015-10-01

    The low‑affinity penicillin‑binding protein (PBP)5 is responsible for resistance to β‑lactam antibiotics in Enterococcus faecium. (E. faecium). In order to evaluate more fully the potential of this species for the development of resistance to β-lactam antibiotics, the present study aimed to examine the extent of penicillin-binding protein (PBP) variations in a collection of clinical E. faecium isolates. In the present study, the C‑terminal domain of PBP5 (PBP5‑CD) of 13 penicillin‑resistant clinical isolates of E. faecium were sequenced and the correlation between penicillin resistance and particular amino acid changes were analyzed. The present study identified for the first time, to the best of our knowledge, two novel substitutions (Tyr460Phe and Ala462Thr or Val462Thr) of E. faecium PBP5‑CD. The covalent interaction between penicillin and PBP5‑CD was also investigated using homology modeling and molecular docking methods. The theoretical calculation revealed that Phe460 and Thr462 were involved in penicillin binding, suggesting that substitutions at these positions exert effects on the affinity for penicillin, and this increased affinity translates into lower resistance in vitro.

  5. A multi-omic analysis of an Enterococcus faecium mutant reveals specific genetic mutations and dramatic changes in mRNA and protein expression

    PubMed Central

    2013-01-01

    Background For a long time, Enterococcus faecium was considered a harmless commensal of the mammalian gastrointestinal (GI) tract and was used as a probiotic in fermented foods. In recent decades, E. faecium has been recognised as an opportunistic pathogen that causes diseases such as neonatal meningitis, urinary tract infections, bacteremia, bacterial endocarditis and diverticulitis. E. faecium could be taken into space with astronauts and exposed to the space environment. Thus, it is necessary to observe the phenotypic and molecular changes of E. faecium after spaceflight. Results An E. faecium mutant with biochemical features that are different from those of the wild-type strain was obtained from subculture after flight on the SHENZHOU-8 spacecraft. To understand the underlying mechanism causing these changes, the whole genomes of both the mutant and the WT strains were sequenced using Illumina technology. The genomic comparison revealed that dprA, a recombination-mediator gene, and arpU, a gene associated with cell wall growth, were mutated. Comparative transcriptomic and proteomic analyses showed that differentially expressed genes or proteins were involved with replication, recombination, repair, cell wall biogenesis, glycometabolism, lipid metabolism, amino acid metabolism, predicted general function and energy production/conversion. Conclusion This study analysed the comprehensive genomic, transcriptomic and proteomic changes of an E. faecium mutant from subcultures that were loaded on the SHENZHOU-8 spacecraft. The implications of these gene mutations and expression changes and their underlying mechanisms should be investigated in the future. We hope that the current exploration of multiple “-omics” analyses of this E. faecium mutant will provide clues for future studies on this opportunistic pathogen. PMID:24373636

  6. A functional collagen adhesin gene, acm, in clinical isolates of Enterococcus faecium correlates with the recent success of this emerging nosocomial pathogen.

    PubMed

    Nallapareddy, Sreedhar R; Singh, Kavindra V; Okhuysen, Pablo C; Murray, Barbara E

    2008-09-01

    Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P faecium infections showed reactivity with recombinant Acm, while only 4 of 30 community and hospitalized patient control group sera reacted (P faecium endocarditis patient sera. Although pulsed-field gel electrophoresis indicated that multiple strains expressed collagen adherence, multilocus sequence typing demonstrated that the majority of collagen-adhering isolates, as well as 16 of 17 endocarditis isolates, are part of the hospital-associated E. faecium genogroup referred to as clonal complex 17 (CC17), which has emerged globally. Taken together, our findings support the hypothesis that Acm has contributed to the emergence of E. faecium and CC17 in nosocomial infections.

  7. In Vivo Transfer of the vanA Resistance Gene from an Enterococcus faecium Isolate of Animal Origin to an E. faecium Isolate of Human Origin in the Intestines of Human Volunteers

    PubMed Central

    Lester, Camilla H.; Frimodt-Møller, Niels; Sørensen, Thomas Lund; Monnet, Dominique L.; Hammerum, Anette M.

    2006-01-01

    Transient colonization by vancomycin-resistant enterococci of animal origin has been documented in the intestines of humans. However, little is known about whether transfer of the vanA gene occurs in the human intestine. Six volunteers ingested a vancomycin-resistant Enterococcus faecium isolate of chicken origin, together with a vancomycin-susceptible E. faecium recipient of human origin. Transconjugants were recovered in three of six volunteers. In one volunteer, not only was vancomycin resistance transferred, but also quinupristin-dalfopristin resistance. This study shows that transfer of the vanA gene from an E. faecium isolate of animal origin to an E. faecium isolate of human origin can occur in the intestines of humans. It suggests that transient intestinal colonization by enterococci carrying mobile elements with resistance genes represents a risk for spread of resistance genes to other enterococci that are part of the human indigenous flora, which can be responsible for infections in certain groups of patients, e.g., immunocompromised patients. PMID:16436715

  8. Comparison of four methods, including semi-automated rep-PCR, for the typing of vancomycin-resistant Enterococcus faecium.

    PubMed

    Bourdon, Nancy; Lemire, Astrid; Fines-Guyon, Marguerite; Auzou, Michel; Périchon, Bruno; Courvalin, Patrice; Cattoir, Vincent; Leclercq, Roland

    2011-01-01

    We have assessed the performance of semi-automated rep-PCR (Diversilab®) and multilocus sequence typing (MLST) in comparison to pulsed-field gel electrophoresis (PFGE) for typing a collection of 29 epidemiologically characterized vancomycin-resistant Enterococcus faecium (VRE). Sixteen strains that harbored the Tn1546 element were typed by PCR mapping. The discriminative power of the typing methods was calculated by the Simpson's index of diversity, and the concordance between methods was evaluated by the Kendall's coefficient of concordance. Semi-automated rep-PCR appeared as discriminative as PFGE and was further compared with PFGE for typing 67 VRE isolated during a hospital outbreak. Rep-PCR appeared to be more discriminative than PFGE for this second set of strains. Reproducibility of DiversiLab® was also tested against 35 selected isolates. Only three showed less than 97% similarity, indicating high reproducibility at this level of discrimination. In conclusion, semi-automated rep-PCR is a useful tool for rapid screening of VRE isolates during an outbreak, although cost of the system may be limiting for routine implementation. PFGE, which remains the reference method, should be used for confirmation and evaluation of the genetic relatedness of epidemic isolates.

  9. Effects of oral administration of heat-killed Enterococcus faecium strain NHRD IHARA in post-weaning piglets.

    PubMed

    Sukegawa, Shin; Ihara, Yasuhiro; Yuge, Kaoruko; Rao, Shengbin; Oka, Kentaro; Arakawa, Fumihiro; Fujimura, Tatsuya; Murakami, Hiroshi; Kurazono, Hisao; Takahashi, Motomichi; Morimatsu, Fumiki

    2014-04-01

    Probiotic bacteria such as lactic acid bacteria (LAB) have recently received attention as candidates for alternative anti-microbial feed additives. We previously isolated Enterococcus faecium strain NHRD IHARA (FERM BP-11090, NHRD IHARA strain) and reported its probiotic efficacy. However, we have not determined the effect of oral administration of heat-killed cells of this strain. Here, we performed two experiments to investigate the effect of oral administration of the heat-killed NHRD IHARA strain on post-weaning piglets. In Experiment 1, there was a significant improvement in growth performance (P = 0.04) and increase in serum immunoglobulin A (IgA) production (P = 0.03) in the group fed heat-killed cells. These results were similar to previous results we obtained with live cells. We also found changes in serum and fecal IgA production that were unrelated to the patterns of microbiotal change. In Experiment 2, we detected a significant improvement in villus growth in the jejunum (P = 0.0002). In conclusion, oral administration of the heat-killed NHRD IHARA strain in post-weaning piglets had the same efficacy as administration of the live strain. The heat-killed NHRD IHARA strain can be used as feed additives to improve pig growth and health on commercial farms.

  10. Design and optimization of fermentation medium for enhanced bacteriocin production by probiotic bacterium Enterococcus faecium MC13.

    PubMed

    Kanmani, Paulraj; Kumar, R Satish; Yuvaraj, N; Paari, K A; Pattukumar, V; Arul, Venkatesan

    2011-01-01

    Statistics-based experimental designs were used to develop a cost-effective medium for enhanced production of viable cells and bacteriocin by probiotic Enterococcus faecium MC13. Carbon, nitrogen, and mineral sources were first screened by one-variable-at-a-time (OVAT) methods. In order to increase yield production, the selected variables were further statistically optimized using response-surface methodology (RSM) with central composite design (CCD). The maximum and minimum levels of the selected variables were determined and a set of 34 experimental runs was performed. The optimum concentrations of the tested variables for production of viable cells (12.24 log CFU mL(-1)) and bacteriocin activity (25,600 AU mL(-1)) were tryptone (10.0 g/L), peptone (6.0 g/L), maltose (3.0 g/L), glucose (9.0 g/L), NaCl (15.0 g/L), sodium citrate (2.5 g/L), sodium acetate (1.0 g/L), and dipotassium PO(4) (0.1 g/L). Threefold increased yield of bacteriocin was achieved in optimized medium compared to the unoptimized counterpart, and this was two times less cost than commercial MRS medium.

  11. Enterococcus faecium HDRsEf1 Protects the Intestinal Epithelium and Attenuates ETEC-Induced IL-8 Secretion in Enterocytes

    PubMed Central

    Xiao, Yuncai; Wang, Xiliang; Bi, Dingren

    2016-01-01

    The probiotic Enterococcus faecium HDRsEf1 (Ef1) has been shown to have positive effects on piglet diarrhoea, but the mechanism has not yet been elucidated. In this study, using the IPEC-J2 cell line to mimic intestinal epithelial cells and enterotoxigenic Escherichia coli (ETEC) K88ac as a representative intestinal pathogen, the mechanism underlying Ef1 protection against an enteropathogen was investigated. The results demonstrated that Ef1 was effective in displacing K88ac from the IPEC-J2 cell layer. Moreover, Ef1 and its cell-free supernatant (S-Ef1) modulate IL-8 released by IPEC-J2 cells. Ef1 and its cell-free supernatant showed the potential to protect enterocytes from an acute inflammatory response. In addition, Ef1 and its cell-free supernatant increased the transepithelial electrical resistance (TEER) of the enterocyte monolayer, thus strengthening the intestinal barrier against ETEC. These results may contribute to the development of therapeutic interventions using Ef1 in intestinal disorders of piglets. PMID:27890970

  12. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    PubMed

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.

  13. Distinct but Spatially Overlapping Intestinal Niches for Vancomycin-Resistant Enterococcus faecium and Carbapenem-Resistant Klebsiella pneumoniae

    PubMed Central

    Caballero, Silvia; Carter, Rebecca; Ke, Xu; Sušac, Bože; Leiner, Ingrid M.; Kim, Grace J.; Miller, Liza; Ling, Lilan; Manova, Katia; Pamer, Eric G.

    2015-01-01

    Antibiotic resistance among enterococci and γ-proteobacteria is an increasing problem in healthcare settings. Dense colonization of the gut by antibiotic-resistant bacteria facilitates their spread between patients and also leads to bloodstream and other systemic infections. Antibiotic-mediated destruction of the intestinal microbiota and consequent loss of colonization resistance are critical factors leading to persistence and spread of antibiotic-resistant bacteria. The mechanisms underlying microbiota-mediated colonization resistance remain incompletely defined and are likely distinct for different antibiotic-resistant bacterial species. It is unclear whether enterococci or γ-proteobacteria, upon expanding to high density in the gut, confer colonization resistance against competing bacterial species. Herein, we demonstrate that dense intestinal colonization with vancomycin-resistant Enterococcus faecium (VRE) does not reduce in vivo growth of carbapenem-resistant Klebsiella pneumoniae. Reciprocally, K. pneumoniae does not impair intestinal colonization by VRE. In contrast, transplantation of a diverse fecal microbiota eliminates both VRE and K. pneumoniae from the gut. Fluorescence in situ hybridization demonstrates that VRE and K. pneumoniae localize to the same regions in the colon but differ with respect to stimulation and invasion of the colonic mucus layer. While VRE and K. pneumoniae occupy the same three-dimensional space within the gut lumen, their independent growth and persistence in the gut suggests that they reside in distinct niches that satisfy their specific in vivo metabolic needs. PMID:26334306

  14. Enterocin B, a new bacteriocin from Enterococcus faecium T136 which can act synergistically with enterocin A.

    PubMed

    Casaus, P; Nilsen, T; Cintas, L M; Nes, I F; Hernández, P E; Holo, H

    1997-07-01

    The strain Enterococcus faecium T136 produces two bacteriocins, enterocin A, a member of the pediocin family of bacteriocins, and a new bacteriocin termed enterocin B. The N-terminal amino acid sequences of enterocins A and B were determined, and the gene encoding enterocin B was sequenced. The primary translation product was a 71 aa peptide containing a leader peptide of the double-glycine type which is cleaved off to give mature enterocin B of 53 aa. Enterocin B does not belong to the pediocin family of bacteriocins and shows strong homology to carnobacteriocin A. However, sequence similarities in their leader peptides and C-termini suggest that enterocin B and carnobacteriocin A are related to bacteriocins of the pediocin family. Enterocins A and B had only slightly different inhibitory spectra, and both were active against a wide range of Gram-positive bacteria, including listeriae, staphylococci and most lactic acid bacteria tested. Both had bactericidal activities, but survival at a frequency of 10(-4)-10(-2) was observed when sensitive cultures were exposed to either bacteriocin. The number of survivors was drastically reduced when a mixture of the two bacteriocins was added to the cells.

  15. Hospital and Community Ampicillin-Resistant Enterococcus faecium Are Evolutionarily Closely Linked but Have Diversified through Niche Adaptation

    PubMed Central

    de Regt, Marieke J. A.; van Schaik, Willem; van Luit-Asbroek, Miranda; Dekker, Huberta A. T.; van Duijkeren, Engeline; Koning, Catherina J. M.; Bonten, Marc J. M.; Willems, Rob J. L.

    2012-01-01

    Background Ampicillin-resistant Enterococcus faecium (ARE) has emerged as a nosocomial pathogen. Here, we quantified ARE carriage in different community sources and determined genetic relatedness with hospital ARE. Methods and Results ARE was recovered from rectal swabs of 24 of 79 (30%) dogs, 11 of 85 (13%) cats and 0 of 42 horses and from 3 of 40 (8%) faecal samples of non-hospitalized humans receiving amoxicillin. Multi-locus Sequence Typing revealed 21 sequence types (STs), including 5 STs frequently associated with hospital-acquired infections. Genes previously found to be enriched in hospital ARE, such as IS16, orf903, orf905, orf907, were highly prevalent in community ARE (≥79%), while genes with a proposed role in pathogenesis, such as esp, hyl and ecbA, were found rarely (≤5%) in community isolates. Comparative genome analysis of 2 representative dog isolates revealed that the dog strain of ST192 was evolutionarily closely linked to two previously sequenced hospital ARE, but had, based on gene content, more genes in common with the other, evolutionarily more distantly related, dog strain (ST266). Conclusion ARE were detected in dogs, cats and sporadically in healthy humans, with evolutionary linkage to hospital ARE. Yet, their accessory genome has diversified, probably as a result of niche adaptation. PMID:22363425

  16. High-level vancomycin resistant Enterococcus faecium related to humans and pigs found in dust from pig breeding facilities.

    PubMed

    Braga, Teresa M; Pomba, Constança; Lopes, M Fátima Silva

    2013-01-25

    Environmental dust from animal breeding facilities was never screened for the presence of enterococci, nor of vancomycin-resistant enterococci (VRE), despite the possibility of being a vehicle of transmission of strains and antibiotic resistance genes between food-producing animals and man. Bio-security measures in pig facilities include disinfection with biocides to avoid the dissemination of opportunistic pathogenic bacteria, namely enterococci and in particular VRE. We thus undertook collection of enterococci and VRE in a representative number of breeding pig facilities in Portugal (n=171) and analyzed their susceptibility to benzalkonium chloride (BC) and chlorhexidine (CHX). A prevalence of 15% of VRE was found, with 6% high-level resistance found, and MIC values for CHX and BC were similar to those commonly found among enterococcal isolates from related environments, 8 μg/ml and 4 μg/ml, respectively. Among the isolated high-level vancomycin resistant Enterococcus faecium carrying the vanA genotype, we found multilocus sequence types closely related to pig and human isolates from European countries and Brazil. These results strongly advise constant surveillance of this environment and its inclusion in future epidemiologic studies on VRE.

  17. Enterococcus faecium Mediastinitis Complicated by Disseminated Candida parapsilosis Infection after Congenital Heart Surgery in a 4-Week-Old Baby

    PubMed Central

    Renk, Hanna; Neunhoeffer, Felix; Hölzl, Florian; Hofbeck, Michael; Kumpf, Matthias

    2015-01-01

    Background. Cardiac surgery offers multiple treatment options for children with congenital heart defects. However, infectious complications still remain a major cause of morbidity and mortality in these patients. Mediastinitis is a detrimental complication in children undergoing cardiac surgery. The risk of mediastinitis after delayed sternal closure is up to 10%. Case Presentation. We report a case of Enterococcus faecium mediastinitis in a 4-week-old female baby on extracorporeal membrane oxygenation after Norwood procedure. Although repeated antibiotic irrigation, debridement, and aggressive antibiotic treatment were started early, the pulmonary situation deteriorated. Candida parapsilosis was isolated from bronchoalveolar lavage after pulmonary hemorrhage. Disseminated C. parapsilosis infection with pulmonary involvement was treated with liposomal amphotericin B. Subsequently, inflammatory markers increased again and eventually C. parapsilosis was isolated from the central venous catheter. Conclusion. Children undergoing delayed sternal closure have a higher risk of mediastinitis. Therefore, antibiotic prophylaxis, for example, for soft tissue infection seems justified. However, long-term antibiotic treatment is a risk factor for fungal superinfection. Antifungal treatment of disseminated C. parapsilosis infection may fail in PICU patients with nonbiological material in place due to capacity of this species to form biofilms on medical devices. Immediate removal of central venous catheters and other nonbiological material is life-saving in these patients. PMID:26605096

  18. Distinct but Spatially Overlapping Intestinal Niches for Vancomycin-Resistant Enterococcus faecium and Carbapenem-Resistant Klebsiella pneumoniae.

    PubMed

    Caballero, Silvia; Carter, Rebecca; Ke, Xu; Sušac, Bože; Leiner, Ingrid M; Kim, Grace J; Miller, Liza; Ling, Lilan; Manova, Katia; Pamer, Eric G

    2015-09-01

    Antibiotic resistance among enterococci and γ-proteobacteria is an increasing problem in healthcare settings. Dense colonization of the gut by antibiotic-resistant bacteria facilitates their spread between patients and also leads to bloodstream and other systemic infections. Antibiotic-mediated destruction of the intestinal microbiota and consequent loss of colonization resistance are critical factors leading to persistence and spread of antibiotic-resistant bacteria. The mechanisms underlying microbiota-mediated colonization resistance remain incompletely defined and are likely distinct for different antibiotic-resistant bacterial species. It is unclear whether enterococci or γ-proteobacteria, upon expanding to high density in the gut, confer colonization resistance against competing bacterial species. Herein, we demonstrate that dense intestinal colonization with vancomycin-resistant Enterococcus faecium (VRE) does not reduce in vivo growth of carbapenem-resistant Klebsiella pneumoniae. Reciprocally, K. pneumoniae does not impair intestinal colonization by VRE. In contrast, transplantation of a diverse fecal microbiota eliminates both VRE and K. pneumoniae from the gut. Fluorescence in situ hybridization demonstrates that VRE and K. pneumoniae localize to the same regions in the colon but differ with respect to stimulation and invasion of the colonic mucus layer. While VRE and K. pneumoniae occupy the same three-dimensional space within the gut lumen, their independent growth and persistence in the gut suggests that they reside in distinct niches that satisfy their specific in vivo metabolic needs.

  19. Molecular characterization of vancomycin-resistant Enterococcus faecium isolates from Bermuda

    PubMed Central

    Akpaka, Patrick Eberechi; Kissoon, Shivnarine; Wilson, Clyde; Jayaratne, Padman; Smith, Ashley; Golding, George R.

    2017-01-01

    Molecular characteristics of vancomycin resistant enterococci isolates from Bermuda Island is currently unknown. This study was conducted to investigate phenotypic and genotypic characteristics of VRE isolates from Bermuda Island using the chromogenic agar, E-tests, polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Eighteen E. faecium isolates were completely analyzed and were all resistant to vancomycin, susceptible to linezolid and quinupristin/dalfopristin, positive for vanA and esp genes. The MLST analysis confirmed most isolates were of the sequence types linked to clonal complex 17 (CC17) that is widely associated with outbreaks in hospitals. Infection control measures, antibiotic stewardship, and surveillance activities will continue to be a priority in hospital on the Island. PMID:28267763

  20. Molecular characterization of vancomycin-resistant Enterococcus faecium isolates from Bermuda.

    PubMed

    Akpaka, Patrick Eberechi; Kissoon, Shivnarine; Wilson, Clyde; Jayaratne, Padman; Smith, Ashley; Golding, George R

    2017-01-01

    Molecular characteristics of vancomycin resistant enterococci isolates from Bermuda Island is currently unknown. This study was conducted to investigate phenotypic and genotypic characteristics of VRE isolates from Bermuda Island using the chromogenic agar, E-tests, polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Eighteen E. faecium isolates were completely analyzed and were all resistant to vancomycin, susceptible to linezolid and quinupristin/dalfopristin, positive for vanA and esp genes. The MLST analysis confirmed most isolates were of the sequence types linked to clonal complex 17 (CC17) that is widely associated with outbreaks in hospitals. Infection control measures, antibiotic stewardship, and surveillance activities will continue to be a priority in hospital on the Island.

  1. [MLST types of vancomycin-resistant Enterococcus faecium strains isolated from blood cultures].

    PubMed

    Arslan, Uğur; Demir, Esra; Oryaşin, Erman; Türk Dağı, Hatice; Tuncer, Inci; Fındık, Duygu; Bozdoğan, Bülent

    2013-07-01

    Enterococci, particularly vancomycin-resistant enterococci (VRE), are important nosocomial pathogens with limited treatment options. Enterococci have low-level resistance to penicillins and aminoglycosides and are intrinsically resistant to cephalosporins. In addition, they can acquire high-level resistance to beta-lactam antibiotics, aminoglycosides and glycopeptides. The aim of this study was to determine glycopeptide resistance mechanisms and genetic relationships of vancomycin-resistant E.faecium strains isolated from blood cultures between 2003-2009 years by molecular epidemiologic methods. A total of 38 VRE strains isolated from blood cultures were included in this study. The isolates were identified by conventional methods and Phoenix 100 BD automated system (Becton Dickinson Diagnostic Systems, USA) and confirmed by sequence analysis of 16S rRNA amplicons. Antibiotic susceptibility tests were performed by the Kirby-Bauer disk diffusion method accor-ding to the CLSI standards. MIC values of vancomycin were determined in vancomycin resistant strains by E-test (AB Biodisk, Sweden) method. Vancomycin resistance genes included vanA, vanB, vanC, and vanD were investigated by polymerase chain reaction (PCR) method. Clonal relationship between strains was determined by pulsed-field gel electrophoresis (PFGE). Sequence analysis was performed for examples selected for multilocus sequence typing (MLST) of each pulsotype and subtype. Thirty eight strains of enterococci isolated from blood cultures were defined as E.faecium by phenotypic methods and confirmed by 16S rRNA sequence analysis. Vancomycin MIC values of strains were determined as > 256 µg/ml by E test. The vanA gene was detected in all isolates. Clonal relationship of 38 isolates E.faecium carrying the vanA gene was determined by PFGE and MLST methods. PFGE detected four pulsotypes (A-D) and one sporadic isolate. Twenty nine strains belonged to A pulsotype, three strains belonged to B pulsotype, two strains

  2. Antimicrobial activity and the presence of virulence factors and bacteriocin structural genes in Enterococcus faecium CM33 isolated from ewe colostrum

    PubMed Central

    Nami, Yousef; Haghshenas, Babak; Haghshenas, Minoo; Yari Khosroushahi, Ahmad

    2015-01-01

    Screening of lactic acid bacteria (LAB) isolated from ewe colostrum led to the identification and isolation of Enterococcus faecium CM33 with interesting features like high survival rates under acidic or bile salts condition, high tolerance for the simulated gastrointestinal condition, and high adhesive potential to Caco-2 cells. According the inhibition of pathogen adhesion test results, this strain can reduce more than 50% adhesion capacity of Escherichia coli, Shigella flexneri, Klebsiella pneumoniae, Listeria monocytogenes, and Staphylococcus aureus to Caco-2 cells. Based on the antibiotic sensitivity test findings, E. faecium CM33 was susceptible to gentamycin, vancomycin, erythromycin, ampicillin, penicillin, tetracycline, and rifampicin, but resistant to chloramphenicol, clindamycin, and kanamycin. Upon assessment of the virulence determinants for E. faecium CM33, this strain was negative for all tested virulence genes. Furthermore, the genome of this strain was evaluated for the incidence of the known enterocin genes by specific PCR amplification and discovered the genes encoding enterocins A, 31, X, and Q. Based on this study findings, the strain E. faecium CM33 can be considered as a valuable nutraceutical and can be introduced as a new potential probiotic. PMID:26284059

  3. Evaluating Pediococcus acidilactici and Enterococcus faecium NRRL B-2354 as Thermal Surrogate Microorganisms for Salmonella for In-Plant Validation Studies of Low-Moisture Pet Food Products.

    PubMed

    Ceylan, Erdogan; Bautista, Derrick A

    2015-05-01

    Pediococcus acidilactici ATCC 8042 and Enterococcus faecium NRRL B-2354 were investigated as potential surrogates for Salmonella serovars using thermal death time kinetics in products such as dry pet foods. The D-values of P. acidilactici ATCC 8042, E. faecium NRRL B-2354, and a cocktail of seven Salmonella serovars associated with low-moisture products were determined in a preservative-free dry pet food product at moisture levels of 9.1, 17.9, and 27.0% and heated between 76.7 and 87.8°C. The D-values were calculated by least squares linear regression. The D-values of P. acidilactici ATCC 8042 were higher than those for the Salmonella serovar cocktail but lower than those for E. faecium NRRL 2354. At 9.1% moisture, D-values of 6.54, 11.51, and 11.66 min at 76.7°C, 2.66, 3.22, and 4.08 min at 82.2°C, and 1.07, 1.29, and 1.69 min at 87.8°C were calculated for Salmonella serovars, P. acidilactici ATCC 8042, and E. faecium NRRL B-2354, respectively. The data suggest that the thermal inactivation characteristics of P. acidilactici ATCC 8042 can be utilized as a surrogate to predict the response of Salmonella in dry pet food products that are thermally processed at <90°C.

  4. Antimicrobial activity and the presence of virulence factors and bacteriocin structural genes in Enterococcus faecium CM33 isolated from ewe colostrum.

    PubMed

    Nami, Yousef; Haghshenas, Babak; Haghshenas, Minoo; Yari Khosroushahi, Ahmad

    2015-01-01

    Screening of lactic acid bacteria (LAB) isolated from ewe colostrum led to the identification and isolation of Enterococcus faecium CM33 with interesting features like high survival rates under acidic or bile salts condition, high tolerance for the simulated gastrointestinal condition, and high adhesive potential to Caco-2 cells. According the inhibition of pathogen adhesion test results, this strain can reduce more than 50% adhesion capacity of Escherichia coli, Shigella flexneri, Klebsiella pneumoniae, Listeria monocytogenes, and Staphylococcus aureus to Caco-2 cells. Based on the antibiotic sensitivity test findings, E. faecium CM33 was susceptible to gentamycin, vancomycin, erythromycin, ampicillin, penicillin, tetracycline, and rifampicin, but resistant to chloramphenicol, clindamycin, and kanamycin. Upon assessment of the virulence determinants for E. faecium CM33, this strain was negative for all tested virulence genes. Furthermore, the genome of this strain was evaluated for the incidence of the known enterocin genes by specific PCR amplification and discovered the genes encoding enterocins A, 31, X, and Q. Based on this study findings, the strain E. faecium CM33 can be considered as a valuable nutraceutical and can be introduced as a new potential probiotic.

  5. Effects of a probiotic, Enterococcus faecium, on growth performance, intestinal morphology, immune response, and cecal microflora in broiler chickens challenged with Escherichia coli K88.

    PubMed

    Cao, G T; Zeng, X F; Chen, A G; Zhou, L; Zhang, L; Xiao, Y P; Yang, C M

    2013-11-01

    The effects of feeding dehydrated Enterococcus faecium on growth performance, immune response, and cecal microflora in broiler chickens challenged with Escherichia coli K88 were investigated. Two hundred eighty-eight 1-d-old birds were randomly assigned to 4 treatments: negative control birds (N-con) fed a basal diet and not challenged with E. coli K88; positive control birds (P-con) fed a basal diet and challenged with E. coli K88; birds fed a basal diet including dehydrated E. faecium (Ef) at 1 × 10(9) cfu/kg of feed and challenged with E. coli K88; and birds fed a basal diet including the antibiotic colistine sulfate (Anti) at 10 mg/kg of feed and challenged with E. coli K88. Birds fed E. faecium had greater (P < 0.05) BW on d 14, 21, and 28 and greater (P < 0.05) jejunal villus height on d 21 and 28 compared with birds on the other treatments. Jejunal crypt depth was decreased (P < 0.05) in birds fed either E. faecium or antibiotic compared with P-con treatment birds on d 10, 21, and 28. Birds fed E. faecium had a greater (P < 0.05) concentration of IL-4 in their jejunal mucosa than did those in the N-con treatment group on d 10, 14, and 21. Infected birds, with or without E. faecium feeding, had a higher (P < 0.05) tumor necrosis factor-α and secreted IgA in their jejunal mucosa than did those in the N-con treatment group on d 10 and 14. Birds fed E. faecium had lower (P < 0.05) concentrations of E. coli on d 14 and 28, less (P < 0.05) Clostridium perfringens on d 28, greater Lactobacillus counts on d 14 and 21, and greater (P < 0.05) Bifidobacterium in their cecal contents on d 21 than did the P-con birds. These results suggest that E. faecium can promote growth performance, improve intestinal morphology, and beneficially manipulate the cecal microflora in broilers challenged with E. coli K88.

  6. Cloning and Heterologous Production of Hiracin JM79, a Sec-Dependent Bacteriocin Produced by Enterococcus hirae DCH5, in Lactic Acid Bacteria and Pichia pastoris▿

    PubMed Central

    Sánchez, Jorge; Borrero, Juan; Gómez-Sala, Beatriz; Basanta, Antonio; Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.

    2008-01-01

    Hiracin JM79 (HirJM79), a Sec-dependent bacteriocin produced by Enterococcus hirae DCH5, was cloned and produced in Lactococcus lactis, Lactobacillus sakei, Enterococcus faecium, Enterococcus faecalis, and Pichia pastoris. For heterologous production of HirJM79 in lactic acid bacteria (LAB), the HirJM79 structural gene (hirJM79), with or without the HirJM79 immunity gene (hiriJM79), was cloned into the plasmid pMG36c under the control of the constitutive promoter P32 and into the plasmid pNZ8048 under the control of the inducible PNisA promoter. For the production of HirJM79 in P. pastoris, the gene encoding the mature HirJM79 protein was cloned into the pPICZαA expression vector. The recombinant plasmids permitted the production of biologically active HirJM79 in the supernatants of L. lactis IL1403, L. lactis NZ9000, L. sakei Lb790, E. faecalis JH2-2, and P. pastoris X-33, the coproduction of HirJM79 and nisin A in L. lactis DPC5598, and the coproduction of HirJM79 and enterocin P in E. faecium L50/14-2. All recombinant LAB produced larger quantities of HirJM79 than E. hirae DCH5, although the antimicrobial activities of most transformants were lower than that predicted from their production of HirJM79. The synthesis, processing, and secretion of HirJM79 proceed efficiently in recombinant LAB strains and P. pastoris. PMID:18310424

  7. Intraepithelial lymphocyte numbers and histomorphological parameters in the porcine gut after Enterococcus faecium NCIMB 10415 feeding in a Salmonella Typhimurium challenge.

    PubMed

    Rieger, J; Janczyk, P; Hünigen, H; Neumann, K; Plendl, J

    2015-03-15

    Salmonellae are among the most widespread sources of foodborne infections and Salmonella Typhimurium, in particular, is correlated with human disease caused by the consumption of contaminated pork. Intraepithelial lymphocytes (IEL) have early contact with intestinal antigens and play an important role in the detection of pathogenic bacteria. The objective of this study was to determine whether a presumed probiotic Enterococcus faecium strain could improve histomorphological and immune system-related parameters of gut function after a Salmonella challenge in weaned pigs. In particular the morphological parameters villus length and width, crypt depth and width as well as the actual enlargement of the intestinal epithelial surface were calculated and the number of IEL was evaluated in sections of the porcine gut. Weaned piglets were challenged with Salmonella enterica serovar Typhimurium DT 104, and half of them also received Enterococcus faecium NCIMB 10415 in the diet. Animals were sacrificed at days post infection (DPI) 2 and 28. The effect of the factors "time post-infection/age" and "probiotic treatment" on jejunal morphology and IEL numbers and distribution was evaluated by light microscopy. The time post-infection had significant effects in both feeding groups. Animals sacrificed at DPI 28 had longer and wider villi, deeper and wider crypts, a higher villus enlargement factor, a higher ratio between villus and crypt enlargement factors as well as more IEL. Probiotic treatment resulted in longer villi, a higher ratio of villus surface/crypt circumference enlargement factors and significantly more IEL. The larger total number of IEL displayed by the probiotic group resulted from significantly higher numbers of IEL at the nuclear and apical levels of the intraepithelial compartment but not from the number of IEL situated at the basement membrane. The probiotic effects were only measurable 28 DPI. It is proposed that Enterococcus faecium NCIMB 10415 exerts an

  8. Effect of Continuous and Sequential Therapy Among Veterans Receiving Daptomycin or Linezolid for Vancomycin-Resistant Enterococcus faecium Bacteremia.

    PubMed

    Britt, Nicholas S; Potter, Emily M; Patel, Nimish; Steed, Molly E

    2017-03-06

    Vancomycin-resistant Enterococcus faecium bloodstream infections (VREF-BSI) cause significant mortality, highlighting the need to optimize treatment. We compared the effectiveness and safety of daptomycin (DAP) and linezolid (LZD) as continuous or sequential therapy for VREF-BSI in a national, retrospective, propensity score (PS) matched cohort study of hospitalized Veterans Affairs patients (2004-2014). We compared clinical outcomes and adverse events among patients treated with continuous LZD, continuous DAP, or sequential LZD followed by DAP (LZD-DAP). Secondarily, we analyzed the impact of infectious diseases (ID) consultation and source of VREF-BSI. A total of 2,779 patients were included (LZD [n=1,348], DAP [n=1,055], LZD-DAP [n=227]). LZD was associated with increased 30-day mortality versus DAP (risk ratio [RR], 1.11; 95% CI, 1.01-1.22; P=0.042). After PS matching, this relationship persisted (RR, 1.13; 95% CI, 1.02-1.26; P=0.015). LZD-DAP switchers had lower mortality than those remaining on LZD (RR, 1.29; 95% CI, 1.03-1.63; P=0.021), suggesting a benefit may still be derived with sequential therapy. LZD-treated patients experienced more adverse events, including ≥ 50% reduction in platelets (RR, 1.07; 95% CI, 1.03-1.11; P=0.001). DAP was associated with lower mortality than LZD in patients with endocarditis (RR, 1.20; 95% CI, 1.02-1.41; P=0.024); however, there was no statistically significant association between treatment group and mortality with regard to other sources of infection. Therefore, source of infection appears to be important in selection of patients most likely to benefit from DAP.

  9. Novel Plasmid-Borne Multidrug Resistance Gene Cluster Including lsa(E) from a Linezolid-Resistant Enterococcus faecium Isolate of Swine Origin

    PubMed Central

    Si, Hongbin; Zhang, Wan-Jiang; Chu, Shengbo; Wang, Xiu-Mei; Dai, Lei; Hua, Xin; Dong, Zhimin

    2015-01-01

    A novel nonconjugative plasmid of 28,489 bp from a porcine linezolid-resistant Enterococcus faecium isolate was completely sequenced. This plasmid harbored a novel type of multiresistance gene cluster that comprised the resistance genes lnu(B), lsa(E), spw, aadE, aphA3, and two copies of erm(B), which account for resistance to macrolides, lincosamides, streptogramins, pleuromutilins, streptomycin, spectinomycin, and kanamycin/neomycin. Structural comparisons suggested that this plasmid might have developed from other enterococcal plasmids by insertion element (IS)-mediated interplasmid recombination processes. PMID:26324271

  10. The N-terminal domain of the thermo-regulated surface protein PrpA of Enterococcus faecium binds to fibrinogen, fibronectin and platelets.

    PubMed

    Guzmán Prieto, Ana M; Urbanus, Rolf T; Zhang, Xinglin; Bierschenk, Damien; Koekman, C Arnold; van Luit-Asbroek, Miranda; Ouwerkerk, Janneke P; Pape, Marieke; Paganelli, Fernanda L; Wobser, Dominique; Huebner, Johannes; Hendrickx, Antoni P A; Bonten, Marc J M; Willems, Rob J L; van Schaik, Willem

    2015-12-17

    Enterococcus faecium is a commensal of the mammalian gastrointestinal tract, but is also found in non-enteric environments where it can grow between 10 °C and 45 °C. E. faecium has recently emerged as a multi-drug resistant nosocomial pathogen. We hypothesized that genes involved in the colonization and infection of mammals exhibit temperature-regulated expression control and we therefore performed a transcriptome analysis of the clinical isolate E. faecium E1162, during mid-exponential growth at 25 °C and 37 °C. One of the genes that exhibited differential expression between 25 °C and 37 °C, was predicted to encode a peptidoglycan-anchored surface protein. The N-terminal domain of this protein is unique to E. faecium and closely related enterococci, while the C-terminal domain is homologous to the Streptococcus agalactiae surface protein BibA. This region of the protein contains proline-rich repeats, leading us to name the protein PrpA for proline-rich protein A. We found that PrpA is a surface-exposed protein which is most abundant during exponential growth at 37 °C in E. faecium E1162. The heterologously expressed and purified N-terminal domain of PrpA was able to bind to the extracellular matrix proteins fibrinogen and fibronectin. In addition, the N-terminal domain of PrpA interacted with both non-activated and activated platelets.

  11. The N-terminal domain of the thermo-regulated surface protein PrpA of Enterococcus faecium binds to fibrinogen, fibronectin and platelets

    PubMed Central

    Guzmán Prieto, Ana M.; Urbanus, Rolf T.; Zhang, Xinglin; Bierschenk, Damien; Koekman, C. Arnold; van Luit-Asbroek, Miranda; Ouwerkerk, Janneke P.; Pape, Marieke; Paganelli, Fernanda L.; Wobser, Dominique; Huebner, Johannes; Hendrickx, Antoni P. A.; Bonten, Marc J. M.; Willems, Rob J. L.; van Schaik, Willem

    2015-01-01

    Enterococcus faecium is a commensal of the mammalian gastrointestinal tract, but is also found in non-enteric environments where it can grow between 10 °C and 45 °C. E. faecium has recently emerged as a multi-drug resistant nosocomial pathogen. We hypothesized that genes involved in the colonization and infection of mammals exhibit temperature-regulated expression control and we therefore performed a transcriptome analysis of the clinical isolate E. faecium E1162, during mid-exponential growth at 25 °C and 37 °C. One of the genes that exhibited differential expression between 25 °C and 37 °C, was predicted to encode a peptidoglycan-anchored surface protein. The N-terminal domain of this protein is unique to E. faecium and closely related enterococci, while the C-terminal domain is homologous to the Streptococcus agalactiae surface protein BibA. This region of the protein contains proline-rich repeats, leading us to name the protein PrpA for proline-rich protein A. We found that PrpA is a surface-exposed protein which is most abundant during exponential growth at 37 °C in E. faecium E1162. The heterologously expressed and purified N-terminal domain of PrpA was able to bind to the extracellular matrix proteins fibrinogen and fibronectin. In addition, the N-terminal domain of PrpA interacted with both non-activated and activated platelets. PMID:26675410

  12. Enterococcus faecium QU 50: a novel thermophilic lactic acid bacterium for high-yield l-lactic acid production from xylose.

    PubMed

    Abdel-Rahman, Mohamed Ali; Tashiro, Yukihiro; Zendo, Takeshi; Sakai, Kenji; Sonomoto, Kenji

    2015-01-01

    Production of optically pure lactic acid from lignocellulosic material for commercial purposes is hampered by several difficulties, including heterofermentation of pentose sugars and high energy consumption by mesophilic lactic acid bacteria. Here, we report a novel lactic acid bacterium, strain QU 50, that has the potential to produce optically pure l-lactic acid (≥99.2%) in a homofermentative manner from xylose under thermophilic conditions. Strain QU 50 was isolated from Egyptian fertile soil and identified as Enterococcus faecium QU 50 by analyzing its sugar fermentation pattern and 16S rRNA gene sequence. Enterococcus faecium QU 50 fermented xylose efficiently to produce lactic acid over wide pH (6.0-10.0) and temperature ranges (30-52°C), with a pH of 6.5 and temperature of 50°C being optimal. To our knowledge, this is the first report of homofermentative lactic acid production from xylose by a thermophilic lactic acid bacterium.

  13. Genome-wide Screening Identifies Phosphotransferase System Permease BepA to Be Involved in Enterococcus faecium Endocarditis and Biofilm Formation.

    PubMed

    Paganelli, Fernanda L; Huebner, Johannes; Singh, Kavindra V; Zhang, Xinglin; van Schaik, Willem; Wobser, Dominique; Braat, Johanna C; Murray, Barbara E; Bonten, Marc J M; Willems, Rob J L; Leavis, Helen L

    2016-07-15

    Enterococcus faecium is a common cause of nosocomial infections, of which infective endocarditis is associated with substantial mortality. In this study, we used a microarray-based transposon mapping (M-TraM) approach to evaluate a rat endocarditis model and identified a gene, originally annotated as "fruA" and renamed "bepA," putatively encoding a carbohydrate phosphotransferase system (PTS) permease (biofilm and endocarditis-associated permease A [BepA]), as important in infective endocarditis. This gene is highly enriched in E. faecium clinical isolates and absent in commensal isolates that are not associated with infection. Confirmation of the phenotype was established in a competition experiment of wild-type and a markerless bepA mutant in a rat endocarditis model. In addition, deletion of bepA impaired biofilm formation in vitro in the presence of 100% human serum and metabolism of β-methyl-D-glucoside. β-glucoside metabolism has been linked to the metabolism of glycosaminoglycans that are exposed on injured heart valves, where bacteria attach and form vegetations. Therefore, we propose that the PTS permease BepA is directly implicated in E. faecium pathogenesis.

  14. Synthesis and Evaluation of 1,2,4-Triazolo[1,5-a]pyrimidines as Antibacterial Agents Against Enterococcus faecium

    PubMed Central

    Wang, Huan; Lee, Mijoon; Peng, Zhihong; Blázquez, Blas; Lastochkin, Elena; Kumarasiri, Malika; Bouley, Renee; Chang, Mayland; Mobashery, Shahriar

    2015-01-01

    Rapid emergence of antibiotic resistance is one of the most challenging global public health concerns. In particular, vancomycin-resistant Enterococcus faecium infections have been increasing in frequency, representing 25% of enterococci infections in intensive care units. A novel class of 1,2,4-triazolo[1,5-a]pyrimidines active against E. faecium is reported herein. We used a three-component Biginelli-like heterocyclization reaction for the synthesis of a series of these derivatives based on reactions of aldehydes, β-dicarbonyl compounds, and 3-alkylthio-5-amino-1,2,4-tria-zoles. The resulting compounds were assayed for antimicrobial activity against the ESKAPE panel of bacteria, followed by investigation of their in vitro activities. These analyses identified a subset of 1,2,4-triazolo[1,5-a]pyrimidines that had good narrow-spectrum antibacterial activity against E. faecium and exhibited metabolic stability with low intrinsic clearance. Macromolecular synthesis assays revealed cell-wall biosynthesis as the target of these antibiotics. PMID:25923368

  15. Anti-Listeria monocytogenes bacteriocin-like inhibitory substances from Enterococcus faecium UQ31 isolated from artisan Mexican-style cheese.

    PubMed

    Alvarado, C; García-Almendárez, B E; Martin, S E; Regalado, C

    2005-08-01

    Artisan fresh Mexican-style cheeses are commonly made from raw milk that provides not only rich flavors, but also a diversity of associated lactic acid bacteria (LAB) strains. Enterococcus faecium UQ31 was isolated from panela cheese and produced bacteriocin-like inhibitory substances (BLIS) with a strong anti-Listeria activity. A modified pH-mediated adsorption-desorption purification process resulted in (after SDS-PAGE) two bands showing antimicrobial activities, where most of the activity corresponded to the band with an estimated molecular weight of 7.5 kDa. The BLIS produced by E. faecium UQ31 were heat resistant, stable at ambient storage conditions, and active in the pH range 5--9. The BLIS antimicrobial activities were detected during logarithmic growth phase and remained constant until the end of incubation time (19 h). These BLIS showed a wide anti-Listeria monocytogenes spectra. The E. faecium UQ31 strain or their BLIS represent a promising potential as antimicrobial food preservatives.

  16. Effects of a probiotic Enterococcus faecium strain supplemented from birth to weaning on diarrhoea patterns and performance of piglets.

    PubMed

    Zeyner, A; Boldt, E

    2006-02-01

    This placebo-controlled double-blind study was conducted to evaluate effects of Enterococcus faecium DSM 10663 NCIMB 10415 (EcF) orally given from birth to weaning on diarrhoea and performance of piglets. At the first 3 days postnatum (p.n.), piglets from 54 [verum group (VG)] and 60 [placebo group (PG)] sows got 1 g of a gel directly per mouth by a dosing device. Gel for the VG contained 2.8 x 10(9) colony forming units (CFU) EcF/g. From day 4 p.n. until weaning (24 +/- 3.2 days p.n.) a liquid additive was given that administered twice a day 1.26 x 10(9) CFU EcF to each VG piglet. In case of diarrhoea, an electrolyte solution was used which provided daily 2.9 and 5.8 (week 1 and >or= 2, respectively) x 10(8) CFU EcF per VG piglet. Diarrhoea scores were defined as follows: (i) no diarrhoea; (ii) piglets developed diarrhoea, but were vital and (iii) piglets suffered from diarrhoea and additionally looked pale, developed rough coat, showed slackening of the flank and lethargy. Counts of viable born, stillborn and weaned piglets were normal and not different between groups (p > 0.05). Placebo group vs. VG piglets suffered more frequently from diarrhoea (40.0 vs. 14.8%, p < 0.05). Duration of diarrhoea was not affected by feeding EcF (2.2 +/- 0.81 days, p > 0.05). Diarrhoea score was lower in VG vs. PG (1.2 vs. 1.5 +/- 0.54, p < 0.05) and the daily weight gain (DWG) was higher by 17 g/day (p < 0.05). Results suggest that the daily oral supplementation of EcF from birth to weaning reduces the portion of piglets suffering from diarrhoea. This may improve performance, as the higher DWG indicates. In contrast, no obvious benefit seems to result from an additional supply of EcF via electrolyte solution when diarrhoea is always present.

  17. Influence of a probiotic Enterococcus faecium strain on development of the immune system of sows and piglets.

    PubMed

    Scharek, L; Guth, J; Reiter, K; Weyrauch, K D; Taras, D; Schwerk, P; Schierack, P; Schmidt, M F G; Wieler, L H; Tedin, K

    2005-05-01

    The influence of the probiotic bacterium Enterococcus faecium SF68 on the immune system and the intestinal colonization of pigs were determined in a feeding experiment with sows and piglets. Mucosal immunity of the developing piglets was monitored by isolation and detection of intestinal lymphocyte cell populations from the proximal jejunal epithelium and the continuous Peyers patches by the use of flow cytometry. The levels of intestinal IgA in both groups of piglets were compared, as well as total IgG in the serum of sows and piglets. Feces of the sows and intestinal contents of the piglets were taken for determination of total anaerobe and coliform bacterial counts in both probiotic and control groups. Villus length and depth of the crypts were measured in the jejunum of sacrificed piglets to monitor the development of the intestinal mucosal surface amplification. Total serum IgG of the sows appeared to be unaffected. Piglets of both groups showed similar IgG levels up to 5 weeks after birth with a slight tendency toward lower values in the probiotic group. At an age of 8 weeks the total IgG levels of the probiotic animals were significantly lower (p<0.01). No differences were observed in the populations of CD4+ and CD8+ T cells in the Peyers patches. However, the levels of cytotoxic T cells (CD8+) in the jejunal epithelium of piglets of the probiotic group were significantly reduced. The depth of the jejunal crypts and length of the villi were similar in both groups, suggesting the relative T-cell population differences were not due to alterations in the epithelial cell numbers. The total anaerobe and coliform bacterial populations were not significantly affected by the probiotic treatment, either in sows or in the piglets. However, a remarkable decline in the frequency of beta-haemolytic and O141 serovars of Escherichia coli was observed in the intestinal contents of probiotic piglets, suggesting an explanation for the reduction in cytotoxic T-cell populations.

  18. Role of the Emp Pilus Subunits of Enterococcus faecium in Biofilm Formation, Adherence to Host Extracellular Matrix Components, and Experimental Infection

    PubMed Central

    Montealegre, Maria Camila; Singh, Kavindra V.; Somarajan, Sudha R.; Yadav, Puja; Chang, Chungyu; Spencer, Robert; Sillanpää, Jouko; Ton-That, Hung

    2016-01-01

    Enterococcus faecium is an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, including E. faecium. We previously demonstrated that a nonpiliated ΔempABC::cat derivative of E. faecium TX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion of empA reduced biofilm formation to the same level as deletion of the empABC operon, a phenotype that was restored by reconstituting in situ the empA gene. Deletion of empB also caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion of empA and empB, while deletion of empC had no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P < 0.001 to 0.048), that reconstitution of empA restored virulence in the UTI model, and that deletion of empA also resulted in attenuation in an infective endocarditis model (P = 0.0088). Our results indicate that EmpA and EmpB, but not EmpC, contribute to biofilm and adherence to ECM proteins; however, all the Emp pilins are important for E. faecium to cause infection in the urinary tract. PMID:26930703

  19. Validation of Baking To Control Salmonella Serovars in Hamburger Bun Manufacturing, and Evaluation of Enterococcus faecium ATCC 8459 and Saccharomyces cerevisiae as Nonpathogenic Surrogate Indicators.

    PubMed

    Channaiah, Lakshmikantha H; Holmgren, Elizabeth S; Michael, Minto; Sevart, Nicholas J; Milke, Donka; Schwan, Carla L; Krug, Matthew; Wilder, Amanda; Phebus, Randall K; Thippareddi, Harshavardhan; Milliken, George

    2016-04-01

    This study was conducted to validate a simulated commercial baking process for hamburger buns to destroy Salmonella serovars and to determine the appropriateness of using nonpathogenic surrogates (Enterococcus faecium ATCC 8459 or Saccharomyces cerevisiae) for in-plant process validation studies. Wheat flour was inoculated (∼6 log CFU/g) with three Salmonella serovars (Typhimurium, Newport, or Senftenberg 775W) or with E. faecium. Dough was formed, proofed, and baked to mimic commercial manufacturing conditions. Buns were baked for up to 13 min in a conventional oven (218.3°C), with internal crumb temperature increasing to ∼100°C during the first 8 min of baking and remaining at this temperature until removal from the oven. Salmonella and E. faecium populations were undetectable by enrichment (>6-log CFU/g reductions) after 9.0 and 11.5 min of baking, respectively, and ≥5-log-cycle reductions were achieved by 6.0 and 7.75 min, respectively. D-values of Salmonella (three-serovar cocktail) and E. faecium 8459 in dough were 28.64 and 133.33, 7.61 and 55.67, and 3.14 and 14.72 min at 55, 58, and 61°C, respectively, whereas D-values of S. cerevisiae were 18.73, 5.67, and 1.03 min at 52, 55, and 58°C, respectivly. The z-values of Salmonella, E. faecium, and S. cerevisiae were 6.58, 6.25, and 4.74°C, respectively. A high level of thermal lethality was observed for baking of typical hamburger bun dough, resulting in rapid elimination of high levels of the three-strain Salmonella cocktail; however, the lethality and microbial destruction kinetics should not be extrapolated to other bakery products without further research. E. faecium demonstrated greater thermal resistance compared with Salmonella during bun baking and could serve as a conservative surrogate to validate thermal process lethality in commercial bun baking operations. Low thermal tolerance of S. cerevisiae relative to Salmonella serovars limits its usefulness as a surrogate for process validations.

  20. Identification of Enterococcus faecium and Enterococcus faecalis as vanC-type Vancomycin-Resistant Enterococci (VRE) from sewage and river water in the provincial city of Miyazaki, Japan.

    PubMed

    Nishiyama, Masateru; Iguchi, Atsushi; Suzuki, Yoshihiro

    2015-01-01

    As a first step for assessing the risk to human health posed by vancomycin-resistant enterococci (VRE) in the aquatic environment, we screened sewage and urban river water samples from Miyazaki, Japan for VRE. Because vancomycin-resistant organisms are not as prevalent in sewage and river water as vancomycin-susceptible organisms, the samples were screened by minimum inhibitory concentration test using the vancomycin-supplemented membrane-Enterococcus indoxyl-β-d-glucoside (mEI) agar. The isolates, presumed to be enterococci, were identified using 16S rRNA sequencing analysis. The percentages of VRE isolates screened using 4 μg mL(-1) vancomycin-supplemented mEI agar from sewage and urban river water samples were 12% and 24%, respectively. The vancomycin-resistant genes vanC1 and vanC2/3 were detected in the isolates from both samples by PCR analysis. All enterococci isolates containing vanC1, which is a specific gene for vanC-type of VRE, were identified as Enterococcus casseliflavus/gallinarum. Further, 92% enterococci isolates containing vanC2/3 were identified as E. casseliflavus/gallinarum, the remaining isolates containing vanC2/3 were E. faecium (4%) and E. faecalis (4%). Thereafter, the distribution of E. faecium and E. faecalis, which are the major types of enterococci in humans containing vanC2/3, was observed in the water samples collected.

  1. Development of Bacteriocinogenic Strains of Saccharomyces cerevisiae Heterologously Expressing and Secreting the Leaderless Enterocin L50 Peptides L50A and L50B from Enterococcus faecium L50▿

    PubMed Central

    Basanta, Antonio; Herranz, Carmen; Gutiérrez, Jorge; Criado, Raquel; Hernández, Pablo E.; Cintas, Luis M.

    2009-01-01

    A segregationally stable expression and secretion vector for Saccharomyces cerevisiae, named pYABD01, was constructed by cloning the yeast gene region encoding the mating pheromone α-factor 1 secretion signal (MFα1s) into the S. cerevisiae high-copy-number expression vector pYES2. The structural genes of the two leaderless peptides of enterocin L50 (EntL50A and EntL50B) from Enterococcus faecium L50 were cloned, separately (entL50A or entL50B) and together (entL50AB), into pYABD01 under the control of the galactose-inducible promoter PGAL1. The generation of recombinant S. cerevisiae strains heterologously expressing and secreting biologically active EntL50A and EntL50B demonstrates the suitability of the MFα1s-containing vector pYABD01 to direct processing and secretion of these antimicrobial peptides through the S. cerevisiae Sec system. PMID:19218405

  2. Molecular analysis and distribution of multidrug-resistant Enterococcus faecium isolates belonging to clonal complex 17 in a tertiary care center in Mexico City

    PubMed Central

    2013-01-01

    Background Enterococcus faecium has recently emerged as a multidrug-resistant nosocomial pathogen involved in outbreaks worldwide. A high rate of resistance to different antibiotics has been associated with virulent clonal complex 17 isolates carrying the esp and hyl genes and the purK1 allele. Results Twelve clinical vancomycin-resistant Enterococcus faecium (VREF) isolates were obtained from pediatric patients at the Hospital Infantil de México Federico Gómez (HIMFG). Among these VREF isolates, 58.3% (7/12) were recovered from urine, while 41.7% (5/12) were recovered from the bloodstream. The VREF isolates showed a 100% rate of resistance to ampicillin, amoxicillin-clavulanate, ciprofloxacin, clindamycin, chloramphenicol, streptomycin, gentamicin, rifampicin, erythromycin and teicoplanin. In addition, 16.7% (2/12) of the isolates were resistant to linezolid, and 66.7% (8/12) were resistant to tetracycline and doxycycline. PCR analysis revealed the presence of the vanA gene in all 12 VREF isolates, esp in 83.3% (10/12) of the isolates and hyl in 50% (6/12) of the isolates. Phylogenetic analysis via molecular typing was performed using pulsed-field gel electrophoresis (PFGE) and demonstrated 44% similarity among the VREF isolates. MLST analysis identified four different sequence types (ST412, ST757, ST203 and ST612). Conclusion This study provides the first report of multidrug-resistant VREF isolates belonging to clonal complex 17 from a tertiary care center in Mexico City. Multidrug resistance and genetic determinants of virulence confer advantages among VREF in the colonization of their host. Therefore, the prevention and control of the spread of nosocomial infections caused by VREF is crucial for identifying new emergent subclones that could be challenging to treat in subsequent years. PMID:24330424

  3. Daptomycin or teicoplanin in combination with gentamicin for treatment of experimental endocarditis due to a highly glycopeptide-resistant isolate of Enterococcus faecium.

    PubMed Central

    Caron, F; Kitzis, M D; Gutmann, L; Cremieux, A C; Maziere, B; Vallois, J M; Saleh-Mghir, A; Lemeland, J F; Carbon, C

    1992-01-01

    Using an experimental endocarditis model, we studied the activity of daptomycin used alone or in combination with gentamicin against an Enterococcus faecium strain that was highly resistant to glycopeptides and susceptible to gentamicin. In vitro, the MIC of daptomycin was 1 micrograms/ml. In vivo, daptomycin appeared to be effective only when it was used in a high-dose regimen, i.e., 12 mg/kg of body weight every 8 h (-2.5 log10 CFU/g versus controls; P < 0.05), particularly when it was combined with gentamicin (-5.0 log10 CFU/g versus controls; P < 0.01). Since the distribution of daptomycin into cardiac vegetations, as evaluated by autoradiography, appeared to be homogeneous, the poor in vivo activity of daptomycin was considered to be related to its high degree of protein binding, as suggested by killing curves studies. Since the MIC of teicoplanin for the vancomycin-resistant E. faecium strain used in the study was only 64 micrograms/ml and since an in vitro synergy between teicoplanin at high dose and gentamicin was observed, a high-dose regimen of teicoplanin, i.e., 40 mg/kg every 12 h, was also assessed in vivo. This treatment provided marginal activity only when it was combined with gentamicin (-2.3 log10 CFU/g versus controls; P < 0.05). These results suggest that the levels of daptomycin or teicoplanin in serum required to cure experimental endocarditis caused by a highly glycopeptide-resistant strain of E. faecium would not be achievable in humans. Images PMID:1336339

  4. Survival of Salmonella Tennessee, Salmonella Typhimurium DT104, and Enterococcus faecium in peanut paste formulations at two different levels of water activity and fat.

    PubMed

    Kataoka, Ai; Enache, Elena; Black, D Glenn; Elliott, Philip H; Napier, Carla D; Podolak, Richard; Hayman, Melinda M

    2014-08-01

    Long-term survival of heat-stressed Salmonella Tennessee, Salmonella Typhimurium DT104, and Enterococcus faecium was evaluated in four model peanut paste formulations with a combination of two water activity (aw) levels (0.3 and 0.6) and two fat levels (47 and 56%) over 12 months at 20 ± 1°C. Prior to storage, the inoculated peanut paste formulations were heat treated at 75°C for up to 50 min to obtain an approximately 1.0-log reduction of each organism. The cell population of each organism in each formulation was monitored with tryptic soy agar plate counts, immediately after heat treatment, at 2 weeks for the first month, and then monthly for up to 1 year. The log reductions (log CFU per gram) following 12 months of storage were between 1.3 and 2.4 for Salmonella Tennessee, 1.8 and 2.8 for Salmonella Typhimurium, and 1.1 and 2.1 for E. faecium in four types of model peanut paste formulations. Enhanced survivability was observed in pastes with lower aw for all organisms, compared with those with higher aw (P < 0.05). In contrast, the effect of fat level (47 and 56%) on survival of all organisms was not statistically significant (P > 0.05). Whereas survivability of Salmonella Tennessee and Typhimurium DT104 did not differ significantly (P > 0.05), E. faecium demonstrated higher survivability than Salmonella (P < 0.05). Salmonella survived in the model peanut pastes well over 12 months, which is longer than the expected shelf life for peanut butter products. The information from this study can be used to design safer food processing and food safety plans for peanut butter processing.

  5. Intrinsic resistance to aminoglycosides in Enterococcus faecium is conferred by the 16S rRNA m5C1404-specific methyltransferase EfmM.

    PubMed

    Galimand, Marc; Schmitt, Emmanuelle; Panvert, Michel; Desmolaize, Benoît; Douthwaite, Stephen; Mechulam, Yves; Courvalin, Patrice

    2011-02-01

    Aminoglycosides are ribosome-targeting antibiotics and a major drug group of choice in the treatment of serious enterococcal infections. Here we show that aminoglycoside resistance in Enterococcus faecium strain CIP 54-32 is conferred by the chromosomal gene efmM, encoding the E. faecium methyltransferase, as well as by the previously characterized aac(6')-Ii that encodes a 6'-N-aminoglycoside acetyltransferase. Inactivation of efmM in E. faecium increases susceptibility to the aminoglycosides kanamycin and tobramycin, and, conversely, expression of a recombinant version of efmM in Escherichia coli confers resistance to these drugs. The EfmM protein shows significant sequence similarity to E. coli RsmF (previously called YebU), which is a 5-methylcytidine (m⁵C) methyltransferase modifying 16S rRNA nucleotide C1407. The target for EfmM is shown by mass spectrometry to be a neighboring 16S rRNA nucleotide at C1404. EfmM uses the methyl group donor S-adenosyl-L-methionine to catalyze formation of m⁵C1404 on the 30S ribosomal subunit, whereas naked 16S rRNA and the 70S ribosome are not substrates. Addition of the 5-methyl to C1404 sterically hinders aminoglycoside binding. Crystallographic structure determination of EfmM at 2.28 Å resolution reveals an N-terminal domain connected to a central methyltransferase domain that is linked by a flexible lysine-rich region to two C-terminal subdomains. Mutagenesis of the methyltransferase domain established that two cysteines at specific tertiary locations are required for catalysis. The tertiary structure of EfmM is highly similar to that of RsmF, consistent with m⁵C formation at adjacent sites on the 30S subunit, while distinctive structural features account for the enzymes' respective specificities for nucleotides C1404 and C1407.

  6. Characterization of Structural Variations in the Peptidoglycan of Vancomycin-Susceptible Enterococcus faecium: Understanding Glycopeptide-Antibiotic Binding Sites using Mass Spectrometry

    PubMed Central

    Patti, Gary J.; Chen, Jiawei; Schaefer, Jacob; Gross, Michael L.

    2008-01-01

    Enterococcus faecium, an opportunistic pathogen that causes a significant number of hospital-acquired infections each year, presents a serious clinical challenge because an increasing number of infections are resistant to the so-called antibiotic of last resort, vancomycin. Vancomycin and other new glycopeptide derivatives target the bacterial cell wall, thereby perturbing its biosynthesis. To help determine the modes of action of glycopeptide antibiotics, we have developed a bottom-up mass spectrometry approach complemented by solid-state NMR to elucidate important structural characteristics of vancomycin-susceptible E. faecium peptidoglycan. Using accurate-mass measurements and integrating ion-current chromatographic peaks of digested peptidoglycan, we identified individual muropeptide species and approximated the relative amount of each. Even though the organism investigated is susceptible to vancomycin, only 3% of the digested peptidoglycan has the well-known D-Ala-D-Ala vancomycin-binding site. The data are consistent with a previously proposed template model of cell-wall biosynthesis where D-Ala-D-Ala stems that are not cross-linked are cleaved in mature peptidoglycan. Additionally, our mass-spectrometry approach allowed differentiation and quantification of muropeptide species seen as unresolved chromatographic peaks. Our method provides an estimate of the extent of muropeptides containing O-acetylation, amidation and hydroxylation, and the number of species forming cyclic imides. The varieties of muropeptides on which the modifications are detected suggest that significant processing occurs in mature peptidoglycan where several enzymes are active in editing cell-wall structure. PMID:18692403

  7. Clinical and molecular epidemiology of hospital Enterococcus faecium isolates in eastern France. Members of Réseau Franc-Comtois de Lutte contr les Infections Nosocomiales.

    PubMed

    Bertrand, X; Thouverez, M; Bailly, P; Cornette, C; Talon, D

    2000-06-01

    We carried out a surveillance study of Enterococcus faecium isolates in the Franche-Comtéregion of France over three years. Clinical and epidemiological strains were characterized by antibiotype and genotype (pulsed field gel electrophoresis, PFGE). Three case-control studies were performed to identify risk factors for colonization/infection with three defined resistant phenotypes (amoxycillin, high-level gentamicin and high-level kanamycin). The crude incidence of colonization/infection was 0.156%, and 68.8% of cases were classified as hospital-acquired. Incidence did not differ according to the type of hospitalization (middle term or acute care). The urinary tract was the major site of infection. Resistance rates were: 45.8% (amoxycillin), 18.7% (high-level gentamicin), 61.4% (high-level kanamycin) and 3.1% (vancomycin). No isolate produced b-lactamase and one isolate carried the vanA gene. PFGE revealed two major epidemic patterns each including resistant strains isolated in different hospitals and during different periods in the study. Previous antimicrobial treatment was not identified as a risk factor for colonization/infection with any resistant phenotype. Despite the low frequency of vancomycin-resistant isolates in this study, resistant strains were widely disseminated and had characteristics enabling them to persist and spread. If these strains acquired the vanA gene, the risk of an outbreak would be large. So, the prevalence of vancomycin-resistant E. faecium in hospitals should be carefully monitored in the future.

  8. Use of the Yeast Pichia pastoris as an Expression Host for Secretion of Enterocin L50, a Leaderless Two-Peptide (L50A and L50B) Bacteriocin from Enterococcus faecium L50▿

    PubMed Central

    Basanta, Antonio; Gómez-Sala, Beatriz; Sánchez, Jorge; Diep, Dzung B.; Herranz, Carmen; Hernández, Pablo E.; Cintas, Luis M.

    2010-01-01

    In this work, we report the expression and secretion of the leaderless two-peptide (EntL50A and EntL50B) bacteriocin enterocin L50 from Enterococcus faecium L50 by the methylotrophic yeast Pichia pastoris X-33. The bacteriocin structural genes entL50A and entL50B were fused to the Saccharomyces cerevisiae gene region encoding the mating pheromone α-factor 1 secretion signal (MFα1s) and cloned, separately and together (entL50AB), into the P. pastoris expression and secretion vector pPICZαA, which contains the methanol-inducible alcohol oxidase promoter (PAOX1) to express the fusion genes. After transfer into the yeast, the recombinant plasmids were integrated into the genome, resulting in three bacteriocinogenic yeast strains able to produce and secrete the individual bacteriocin peptides EntL50A and EntL50B separately and together. The secretion was efficiently directed by MFα1s through the Sec system, and the precursor peptides were found to be correctly processed to form mature and active bacteriocin peptides. The present work describes for the first time the heterologous expression and secretion of a two-peptide non-pediocin-like bacteriocin by a yeast. PMID:20348300

  9. Role of EfrAB efflux pump in biocide tolerance and antibiotic resistance of Enterococcus faecalis and Enterococcus faecium isolated from traditional fermented foods and the effect of EDTA as EfrAB inhibitor.

    PubMed

    Lavilla Lerma, Leyre; Benomar, Nabil; Valenzuela, Antonio Sánchez; Casado Muñoz, María del Carmen; Gálvez, Antonio; Abriouel, Hikmate

    2014-12-01

    Enterococcus faecalis and Enterococcus faecium isolated from various traditional fermented foods of both animal and vegetable origins have shown multidrug resistance to several antibiotics and tolerance to biocides. Reduced susceptibility was intra and inter-species dependent and was due to specific and unspecific mechanisms such as efflux pumps. EfrAB, a heterodimeric ABC transporter efflux pump, was detected in 100% of multidrug resistant (MDR) E. faecalis strains and only in 12% of MDR E. faecium strains. EfrAB expression was induced by half of minimum inhibitory concentration (MIC) of gentamicin, streptomycin and chloramphenicol. However, expression of efrA and efrB genes was highly dependent on the strain tested and on the antimicrobial used. Our results indicated that 3 mM EDTA highly reduced the MICs of almost all drugs tested. Nevertheless, the higher reductions (>8 folds) were obtained with gentamicin, streptomycin, chlorhexidine and triclosan. Reductions of MICs were correlated with down-regulation of EfrAB expression (10-140 folds) in all three MDR enterococci strains. This is the first report describing the role of EfrAB in the efflux of antibiotics and biocides which reflect also the importance of EfrAB in multidrug resistance in enterococci. EDTA used at low concentration as food preservative could be one of the best choices to prevent spread of multidrug resistant enterococci throughout food chain by decreasing EfrAB expression. EfrAB could be an attractive target not only in enterococci present in food matrix but also those causing infections as well by using EDTA as therapeutic agent in combination with low doses of antibiotics.

  10. Development of a Dry Inoculation Method for Thermal Challenge Studies in Low-Moisture Foods by Using Talc as a Carrier for Salmonella and a Surrogate (Enterococcus faecium).

    PubMed

    Enache, Elena; Kataoka, Ai; Black, D Glenn; Napier, Carla D; Podolak, Richard; Hayman, Melinda M

    2015-06-01

    The objective of this study was to obtain dry inocula of Salmonella Tennessee and Enterococcus faecium, a surrogate for thermal inactivation of Salmonella in low-moisture foods, and to compare their thermal resistance and stability over time in terms of survival. Two methods of cell growth were compared: cells harvested from a lawn on tryptic soy agar (TSA-cells) and from tryptic soy broth (TSB-cells). Concentrated cultures of each organism were inoculated onto talc powder, incubated at 35 °C for 24 h, and dried for additional 24 h at room temperature (23 ± 2 °C) to achieve a final water activity of ≤ 0.55 before sieving. Cell reductions of Salmonella and E. faecium during the drying process were between 0.14 and 0.96 log CFU/g, depending on growth method used. There was no difference between microbial counts at days 1 and 30. Heat resistance of the dry inoculum on talc inoculated into a model peanut paste (50 % fat and 0.6 water activity) was determined after 1 and 30 days of preparation, using thermal death time tests conducted at 85 °C. For Salmonella, there was no significant difference between the thermal resistance (D(85 °C)) for the TSB-cells and TSA-cells (e.g. day 1 cells D(85 °C) = 1.05 and 1.07 min, respectively), and there was no significant difference in D(85 °C) between dry inocula on talc used either 1 or 30 days after preparation (P > 0.05). However, the use the dry inocula of E. faecium yielded different results: the TSB-grown cells had a significantly (P < 0.05) greater heat resistance than TSA-grown cells (e.g. D(85 °C) for TSB-cells = 3.42 min versus 2.60 min for TSA-cells). E. faecium had significantly (P < 0.05) greater heat resistance than Salmonella Tennessee regardless what cell type was used for dry inoculum preparation; therefore, it proved to be a conservative but appropriate surrogate for thermal inactivation of Salmonella in low-moisture food matrices under the tested conditions.

  11. Population Structure of Enterococcus faecium Causing Bacteremia in a Spanish University Hospital: Setting the Scene for a Future Increase in Vancomycin Resistance?

    PubMed Central

    Coque, Teresa M.; Willems, Rob J. L.; Fortún, Jesús; Top, Janetta; Diz, Sergio; Loza, Elena; Cantón, Rafael; Baquero, Fernando

    2005-01-01

    Over an 8-year period (1995 to 2002), 86 Enterococcus faecium blood isolates from 84 patients, of which 54 were ampicillin resistant (AREF) and 32 were ampicillin susceptible (ASEF), were studied in a university hospital (1,200 beds; serving a population of 600,000) in Spain, a country characterized by a near-absence of resistance to vancomycin and very high rates of ampicillin resistance among enterococci. Clonal relatedness by pulsed-field gel electrophoresis (PFGE), antibiotic susceptibility, presence of the virulence/epidemicity genes espEfm and hylEfm, and identification of purK alleles were studied. A group of isolates was also analyzed by amplified fragment length polymorphism (AFLP) and multilocus sequence typing. Medical charts (30 variables collected) were reviewed for 60/84 patients. ASEF showed high clonal diversity (32 PFGE types, 11 purK alleles, 4 AFLP genogroups), did not harbor putative virulence genes, and had no specific association with hospital acquisition. AREF isolates belonged to a clonal complex (CC) of genetically related strains (purK-1, AFLP genogroup C), occasionally harboring putative virulence traits, and were from patients with particular risk factors. Within this CC, previously associated with vancomycin-resistant E. faecium isolates causing outbreaks worldwide (W. L. Homan et al., J. Clin. Microbiol. 40:1963-1971, 2002), a great genetic diversity of antibiotic resistance and virulence/epidemicity profiles was found. Associations between esp and a >7-day hospital stay and between purK-1, hospital location, and nosocomial acquisition were noted (P < 0.001). These findings reflect the importance of local environmental differences in the evolution of this CC, suggesting that the emergence of vancomycin resistance among AREF strains in Spain may be a question of time. PMID:15980338

  12. Prevalence and mechanism of resistance against macrolides, lincosamides, and streptogramins among Enterococcus faecium isolates from food-producing animals and hospital patients in Belgium.

    PubMed

    De Graef, E M; Decostere, A; De Leener, E; Goossens, H; Baele, M; Haesebrouck, F

    2007-01-01

    The prevalence of acquired resistance to streptogramins, macrolides, and lincosamides and the genetic background of this resistance was investigated in Enterococcus faecium strains isolated from food-producing animals and hospital patients 4-5 years after the ban of streptogramins as growth promoters. The minimum inhibitory concentrations (MICs) of quinupristin/dalfopristin (Q/D), virginiamycin M1 (virgM1), erythromycin (ery), tylosin (tyl), and lincomycin (lin) were determined by the agar dilution method for E. faecium isolates derived from pigs (80), broilers (45), and hospitalized patients (103). Resistance or susceptibility was interpreted using a microbiological criterion and breakpoints recommended by the Clinical Laboratory Standards Institute (CLSI), if available. The isolates were also screened by PCR for erm(B), lnu(A), lnu(B), mef(A/E), vat(D), vat(E), vga(A), vga(B), and vgb(A) genes. Acquired resistance to Q/D, virgM1, ery, tyl, and lin was detected in 34%, 96%, 46%, 46%, and 69% of the porcine strains, respectively. For broiler strains this was 15% (Q/D), 98% (virgM1), 69% (ery), 71% (tyl), and 89% (lin) and for human strains 23% (Q/D), 65% (virgM1), 54% (ery), 52% (tyl), and 60% (lin). Strains showing cross-resistance against macrolides and lincosamides almost always carried the erm(B) gene. This gene was present in 64% of the Q/D-resistant isolates. Only in two human and three broiler Q/D- and virgM1-resistant isolates, a combination of the erm(B) and vat(D) or vat(E) genes was found. The genetic background of resistance could not be determined in the other Q/D- or virgM1-resistant strains. This study demonstrates that streptogramin resistance is frequently present in strains from hospitalized patients and food-producing animals, but the genetic basis hitherto mostly remains obscure.

  13. Detection of vancomycin-resistant enterococci from faecal samples of Iberian wolf and Iberian lynx, including Enterococcus faecium strains of CC17 and the new singleton ST573.

    PubMed

    Gonçalves, Alexandre; Igrejas, Gilberto; Radhouani, Hajer; López, María; Guerra, Ana; Petrucci-Fonseca, Francisco; Alcaide, Eva; Zorrilla, Irene; Serra, Rodrigo; Torres, Carmen; Poeta, Patrícia

    2011-12-01

    The aim of this study was to perform the molecular characterization of vancomycin resistant enterococci (VRE) within the faecal flora of Iberian wolf and Iberian lynx. The association with other resistance genes and the detection of virulence genes were also analysed. From 2008 to 2010, 365 faecal samples from Iberian wolf and Iberian lynx were collected and tested for VRE recovery. Mechanisms of resistance to vancomycin and other antibiotics, as well as genes encoding virulence factors were detected through PCR. Multilocus Sequence Typing (MLST) was performed for Enterococcus faecium strains. VRE were recovered in 8 of the 365 analysed samples. The vanA gene was identified in two E. faecium isolates recovered from Iberian wolf faecal samples and the remaining six showed intrinsic resistance (3 vanC1-E. gallinarum and 3 vanC2-E. casseliflavus, from Iberian wolf and Iberian lynx faecal samples, respectively). One vanA-containing isolate showed tetracycline and erythromycin resistance [with erm(B) and tet(L) genes] and the other one also exhibited ampicillin and kanamycin resistance [with erm(B), tet(M) and aph(3')-III genes]. One of the vanA-isolates revealed a new sequence type named ST573 and the other one belonged to the CC17 clonal complex (ST18). The hyl gene was detected in one E. casseliflavus and three E. gallinarum but not among vanA-positive isolates, and the occurrence of cylA and cylL genes was confirmed in two E. casseliflavus isolates. A low prevalence of VRE has been detected in faecal samples of Iberian wolf and Iberian lynx and strains with an acquired mechanism of resistance to vancomycin have not been detected among Iberian lynx.

  14. Effect of vancomycin, tylosin, and chlortetracycline on vancomycin-resistant Enterococcus faecium colonization of broiler chickens during grow-out

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler chickens may serve as reservoirs for human colonization by vancomycin-resistant Enterococcus (VRE). We examined the effects of vancomycin and two commonly-used antimicrobial feed additives on VRE colonization in broiler chickens during grow-out. Chicks received unsupplemented feed or feed ...

  15. SgrA, a nidogen-binding LPXTG surface adhesin implicated in biofilm formation, and EcbA, a collagen binding MSCRAMM, are two novel adhesins of hospital-acquired Enterococcus faecium.

    PubMed

    Hendrickx, Antoni P A; van Luit-Asbroek, Miranda; Schapendonk, Claudia M E; van Wamel, Willem J B; Braat, Johanna C; Wijnands, Lucas M; Bonten, Marc J M; Willems, Rob J L

    2009-11-01

    Hospital-acquired Enterococcus faecium isolates responsible for nosocomial outbreaks and invasive infections are enriched in the orf2351 and orf2430 genes, encoding the SgrA and EcbA LPXTG-like cell wall-anchored proteins, respectively. These two surface proteins were characterized to gain insight into their function, since they may have favored the rapid emergence of this nosocomial pathogen. We are the first to identify a surface adhesin among bacteria (SgrA) that binds to the extracellular matrix molecules nidogen 1 and nidogen 2, which are constituents of the basal lamina. EcbA is a novel E. faecium MSCRAMM (microbial surface component recognizing adhesive matrix molecules) that binds to collagen type V. In addition, both SgrA and EcbA bound to fibrinogen; however, SgrA targeted the alpha and beta chains, whereas EcbA bound to the gamma chain of fibrinogen. An E. faecium sgrA insertion mutant displayed reduced binding to both nidogens and fibrinogen. SgrA did not mediate binding of E. faecium cells to biotic materials, such as human intestinal epithelial cells, human bladder cells, and kidney cells, while this LPXTG surface adhesin is implicated in E. faecium biofilm formation. The acm and scm genes, encoding two other E. faecium MSCRAMMs, were expressed at the mRNA level together with sgrA during all phases of growth, whereas ecbA was expressed only in exponential and late exponential phase, suggesting orchestrated expression of these adhesins. Expression of these surface proteins, which bind to extracellular matrix proteins and are involved in biofilm formation (SgrA), may contribute to the pathogenesis of hospital-acquired E. faecium infections.

  16. Evaluation of a novel method based on amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) for typing strains of vancomycin-resistant Enterococcus faecium.

    PubMed

    Krawczyk, Beata; Lewandowski, Krzysztof; Bronk, Marek; Samet, Alfred; Myjak, Przemysław; Kur, Józef

    2003-03-01

    In the search for an effective DNA-typing technique for use in hospital epidemiology, the performance and convenience of a novel assay based on the fingerprinting of bacterial genomes by amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) was tested. A large number of vancomycin-resistant Enterococcus faecium (VREM) isolates from haematological ward patients of the Clinical Hospital in Gdańsk were examined. We found that ADSRRS fingerprinting analysis is a rapid method that offers good discriminatory power. The method demonstrated also excellent reproducibility. The usefulness of the ADSRRS fingerprinting method for molecular typing was compared with pulsed field gel electrophoresis (PFGE) method, which is currently considered the gold standard for molecular typing of isolates recovered from patients and the environment in the course of investigation and control of nosocomial outbreaks. Clustering of ADSRRS fingerprinting data matched pulsed field gel electrophoresis data. The features of ADSRRS fingerprinting technique is discussed in comparison with conventional methods. Data presented here demonstrate the complexity of the epidemiological situation concerning VREM that may occur in a single medical ward.

  17. The VanS-VanR two-component regulatory system controls synthesis of depsipeptide peptidoglycan precursors in Enterococcus faecium BM4147.

    PubMed Central

    Arthur, M; Molinas, C; Courvalin, P

    1992-01-01

    Plasmid pIP816 of Enterococcus faecium BM4147 confers inducible resistance to vancomycin and encodes the VanH dehydrogenase and the VanA ligase for synthesis of depsipeptide-containing peptidoglycan precursors which bind the antibiotic with reduced affinity. We have characterized a cluster of five genes of pIP816 sufficient for peptidoglycan synthesis in the presence of vancomycin. The distal part of the van cluster encodes VanH, VanA, and a third enzyme, VanX, all of which are necessary for resistance. Synthesis of these enzymes was regulated at the transcriptional level by the VanS-VanR two-component regulatory system encoded by the proximal part of the cluster. VanR was a transcriptional activator related to response regulators of the OmpR subclass. VanS stimulated VanR-dependent transcription and was related to membrane-associated histidine protein kinases which control the level of phosphorylation of response regulators. Analysis of transcriptional fusions with a reporter gene and RNA mapping indicated that the VanR-VanS two-component regulatory system activates a promoter used for cotranscription of the vanH, vanA, and vanX resistance genes. Images PMID:1556077

  18. Mass transfer characterization of gamma-aminobutyric acid production by Enterococcus faecium CFR 3003: encapsulation improves its survival under simulated gastro-intestinal conditions.

    PubMed

    Divyashri, Gangaraju; Prapulla, Siddalingaiya Gurudatt

    2015-03-01

    Gamma-aminobutyric acid (GABA) production by free and Ca-alginate encapsulated cells of Enterococcus faecium CFR 3003 was investigated. Mass transfer rates characterizing the GABA production process using encapsulated cells were investigated. Experiments were performed to investigate external film and internal pore diffusion mass transfer rates. The Damkohler and Thiele analysis provides a good description of external film and internal pore diffusion resistances, respectively. The experiments revealed that the external film effects could be neglected but the process is affected to the greater extent by internal mass transfer effects and was found to be the principal rate-controlling step. Protective effect of encapsulation on cell survivability was tested under digestive environment, when challenged to salivary α-amylase, simulated gastric fluid and intestinal fluid. Viability of encapsulated cells was significantly higher under simulated gastro-intestinal conditions and could produce higher GABA than those observed with free cells. The results indicate that the Ca-alginate encapsulated probiotics could effectively be delivered to the colonic site for effective inhibitory action.

  19. Colonisation of poultry by Salmonella Enteritidis S1400 is reduced by combined administration of Lactobacillus salivarius 59 and Enterococcus faecium PXN-33.

    PubMed

    Carter, Alun; Adams, Martin; La Ragione, Roberto M; Woodward, Martin J

    2017-02-01

    Salmonella Enteritidis remains a significant issue within the poultry industry and one potential solution is to use probiotic bacteria to prevent Salmonella colonisation through competitive exclusion (CE). We demonstrate that combined administration of Lactobacillus salivarius 59 and Enterococcus faecium PXN33 were effective competitive excluders of Salmonella Enteritidis S1400 in poultry. Two models were developed to evaluate the efficacy of probiotic where birds received Salmonella Enteritidis S1400 by a) oral gavage and b) sentinel bird to bird transmission. A statistically significant (p<0.001) 2 log reduction of Salmonella Enteritidis S1400 colonisation was observed in the ileum, caecum and colon at day 43 using combined administration of the two probiotic bacteria. However, no Salmonella Enteritidis S1400 colonisation reduction was observed when either probiotic was administered individually. In the sentinel bird model the combined probiotic administered at days 12 and 20 was more effective than one-off or double administrations at age 1 and 12days. In vitro cell free culture supernatant studies suggest the mechanism of Salmonella Enteritidis S1400 inhibition was due to a reduction in pH by the probiotic bacteria. Our current study provides further evidence that probiotics can significantly reduce pathogenic bacterial colonisation in poultry and that mixed preparation of probiotics provide superior performance when compared to individual bacterial preparations.

  20. Oven, microwave, and combination roasting of peanuts: comparison of inactivation of salmonella surrogate Enterococcus faecium, color, volatiles, flavor, and lipid oxidation.

    PubMed

    Smith, Alicia L; Perry, Jennifer J; Marshall, Julie A; Yousef, Ahmed E; Barringer, Sheryl A

    2014-08-01

    Peanut safety and quality were evaluated for different roasting technologies. Shelled raw peanuts were roasted using an oven at 163 to 204 °C, microwave, or oven and microwave combinations. The lethal effect of these treatments was investigated on peanuts inoculated with the Salmonella surrogate, Enterococcus faecium and stored at room temperature for 1 h, 24 h, or 7 d before roasting. Roasted peanut color, odor activity values (OAVs), descriptive sensory panel analysis, free fatty acid, and peroxide values were determined. Color and OAVs were also analyzed on 2 commercial peanut butters. OAVs were calculated using volatile levels quantified with selected ion flow tube mass spectrometry and known odor thresholds. All treatments resulted in a minimum of 3 log reduction of inoculated bacterial population. Resistance to the process was not influenced by storage of inoculated peanuts prior to treatment. Roasting by different methods produced equivalent, commercially ideal L* color. Based on the OAVs, treatments had similar volatiles important to flavor compared to the commercial samples. Descriptive sensory analysis showed no significant difference between the roasting treatments for most of the sensory attributes. Lipid oxidation was not significantly different between the roasting methods, displaying no evidence that roasting time or temperature affected lipid oxidation, when ideal color was produced. These results suggest that oven, microwave, or combination roasting should be sufficient to mitigate the threat of Salmonella contamination and produce similar color, OAVs, sensory attributes, and lipid oxidation results.

  1. Identification and phenotypic characterization of a second collagen adhesin, Scm, and genome-based identification and analysis of 13 other predicted MSCRAMMs, including four distinct pilus loci, in Enterococcus faecium.

    PubMed

    Sillanpää, Jouko; Nallapareddy, Sreedhar R; Prakash, Vittal P; Qin, Xiang; Höök, Magnus; Weinstock, George M; Murray, Barbara E

    2008-10-01

    Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about the pathogenic determinants of this organism. We have previously identified a cell-wall-anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad-spectrum binding to extracellular matrix proteins. Here, we analysed the draft genome of strain TX0016 for potential microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). Genome-based bioinformatics identified 22 predicted cell-wall-anchored E. faecium surface proteins (Fms), of which 15 (including Acm) had characteristics typical of MSCRAMMs, including predicted folding into a modular architecture with multiple immunoglobulin-like domains. Functional characterization of one [Fms10; redesignated second collagen adhesin of E. faecium (Scm)] revealed that recombinant Scm(65) (A- and B-domains) and Scm(36) (A-domain) bound to collagen type V efficiently in a concentration-dependent manner, bound considerably less to collagen type I and fibrinogen, and differed from Acm in their binding specificities to collagen types IV and V. Results from far-UV circular dichroism measurements of recombinant Scm(36) and of Acm(37) indicated that these proteins were rich in beta-sheets, supporting our folding predictions. Whole-cell ELISA and FACS analyses unambiguously demonstrated surface expression of Scm in most E. faecium isolates. Strikingly, 11 of the 15 predicted MSCRAMMs clustered in four loci, each with a class C sortase gene; nine of these showed similarity to Enterococcus faecalis Ebp pilus subunits and also contained motifs essential for pilus assembly. Antibodies against one of the predicted major pilus proteins, Fms9 (redesignated EbpC(fm)), detected a 'ladder' pattern of high-molecular-mass protein bands in a

  2. Population structure and acquisition of the vanB resistance determinant in German clinical isolates of Enterococcus faecium ST192

    PubMed Central

    Bender, Jennifer K.; Kalmbach, Alexander; Fleige, Carola; Klare, Ingo; Fuchs, Stephan; Werner, Guido

    2016-01-01

    In the context of the global action plan to reduce the dissemination of antibiotic resistances it is of utmost importance to understand the population structure of resistant endemic bacterial lineages and to elucidate how bacteria acquire certain resistance determinants. Vancomycin resistant enterococci represent one such example of a prominent nosocomial pathogen on which nation-wide population analyses on prevalent lineages are scarce and data on how the bacteria acquire resistance, especially of the vanB genotype, are still under debate. With respect to Germany, an increased prevalence of VRE was noted in recent years. Here, invasive infections caused by sequence type ST192 VRE are often associated with the vanB-type resistance determinant. Hence, we analyzed 49 vanB-positive and vanB-negative E. faecium isolates by means of whole genome sequencing. Our studies revealed a distinct population structure and that spread of the Tn1549-vanB-type resistance involves exchange of large chromosomal fragments between vanB-positive and vanB-negative enterococci rather than independent acquisition events. In vitro filter-mating experiments support the hypothesis and suggest the presence of certain target sequences as a limiting factor for dissemination of the vanB element. Thus, the present study provides a better understanding of how enterococci emerge into successful multidrug-resistant nosocomial pathogens. PMID:26902259

  3. Biochemical and genetic characterization of enterocin P, a novel sec-dependent bacteriocin from Enterococcus faecium P13 with a broad antimicrobial spectrum.

    PubMed Central

    Cintas, L M; Casaus, P; Håvarstein, L S; Hernández, P E; Nes, I F

    1997-01-01

    Enterocin P is a new bacteriocin produced by Enterococcus faecium P13 isolated from a Spanish dry-fermented sausage. Enterocin P inhibited most of tested spoilage and food-borne gram-positive pathogenic bacteria, such as Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens, and Clostridium botulinum. Enterocin P is produced during growth in MRS broth from 16 to 45 degrees C; it is heat resistant (60 min at 100 degrees C; 15 min at 121 degrees C) and can withstand exposure to pH between 2.0 and 11.0, freeze-thawing, lyophilization, and long-term storage at 4 and -20 degrees C. The bacteriocin was purified to homogeneity by ammonium sulfate precipitation, gel filtration, cation-exchange, hydrophobic-interaction, and reverse-phase liquid chromatography. The sequence of 43 amino acids of the N terminus was obtained by Edman degradation. DNA sequencing analysis of a 755-bp region revealed the presence of two consecutive open reading frames (ORFs). The first ORF encodes a 71-amino-acid protein containing a hydrophobic N-terminal sec-dependent leader sequence of 27 amino acids followed by the amino acid sequence corresponding to the purified and sequenced enterocin P. The bacteriocin is apparently synthesized as a prepeptide that is cleaved immediately after the Val-Asp-Ala residues (positions -3 to -1), resulting in the mature bacteriocin consisting of 44 amino acids, and with a theoretical molecular weight of 4,493. A second ORF, encoding a putative immunity protein composed of 88 amino acids with a calculated molecular weight of 9,886, was found immediately downstream of the enterocin P structural gene. Enterocin P shows a strong antilisterial activity and has the consensus sequence found in the pediocin-like bacteriocins; however, enterocin P is processed and secreted by the sec-dependent pathway. PMID:9361419

  4. The Enterococcus faecium enterococcal biofilm regulator, EbrB, regulates the esp operon and is implicated in biofilm formation and intestinal colonization.

    PubMed

    Top, Janetta; Paganelli, Fernanda L; Zhang, Xinglin; van Schaik, Willem; Leavis, Helen L; van Luit-Asbroek, Miranda; van der Poll, Tom; Leendertse, Masja; Bonten, Marc J M; Willems, Rob J L

    2013-01-01

    Nowadays, Enterococcus faecium is one of the leading nosocomial pathogens worldwide. Strains causing clinical infections or hospital outbreaks are enriched in the enterococcal surface protein (Esp) encoding ICEEfm1 mobile genetic element. Previous studies showed that Esp is involved in biofilm formation, endocarditis and urinary tract infections. In this study, we characterized the role of the putative AraC type of regulator (locus tag EfmE1162_2351), which we renamed ebrB and which is, based on the currently available whole genome sequences, always located upstream of the esp gene, and studied its role in Esp surface exposure during growth. A markerless deletion mutant of ebrB resulted in reduced esp expression and complete abolishment of Esp surface exposure, while Esp cell-surface exposure was restored when this mutant was complemented with an intact copy of ebrB. This demonstrates a role for EbrB in esp expression. However, during growth, ebrB expression levels did not change over time, while an increase in esp expression at both RNA and protein level was observed during mid-log and late-log phase. These results indicate the existence of a secondary regulation system for esp, which might be an unknown quorum sensing system as the enhanced esp expression seems to be cell density dependent. Furthermore, we determined that esp is part of an operon of at least 3 genes putatively involved in biofilm formation. A semi-static biofilm model revealed reduced biofilm formation for the EbrB deficient mutant, while dynamics of biofilm formation using a flow cell system revealed delayed biofilm formation in the ebrB mutant. In a mouse intestinal colonization model the ebrB mutant was less able to colonize the gut compared to wild-type strain, especially in the small intestine. These data indicate that EbrB positively regulates the esp operon and is implicated in biofilm formation and intestinal colonization.

  5. Virulence determinants in vancomycin-resistant Enterococcus faecium vanB: clonal distribution, prevalence and significance of esp and hyl in Australian patients with haematological disorders.

    PubMed

    Worth, L J; Slavin, M A; Vankerckhoven, V; Goossens, H; Grabsch, E A; Thursky, K A

    2008-02-01

    European studies have suggested that the esp gene and other virulence factors have roles in vancomycin-resistant Enterococcus faecium (VREfm) infections. The aim of this study was to examine the relationship between the spectrum of clinical disease and putative virulence factors in vanB VREfm isolates. A multiplex polymerase chain reaction was used to amplify potential virulence genes (asa1, gel E, cylA, esp and hyl) in VREfm isolates obtained from an Australian population of haematology patients. Clonality was assessed by pulsed-field gel electrophoresis (PFGE) and automated ribotyping. Infection, requirement for intensive care unit (ICU) admission and all-cause 30-day mortality were used as clinical indicators of organism virulence. Forty-one VREfm vanB isolates (41 patients; 14 infected and 27 colonised only) were analysed. Thirty-five of these isolates were typed by PFGE, 31 of which were represented by three clusters. The esp gene was identified in 22 of 27 (81.5%) screening and 11 of 14 (78.6%) infection-associated isolates. One isolate was hyl gene positive, and no isolate contained asa1, gel E or cylA genes. VREfm infection was independently associated with host factors (underlying diagnosis of acute myeloid leukaemia, age

  6. Linezolid in the treatment of vancomycin-resistant Enterococcus faecium in solid organ transplant recipients: report of a multicenter compassionate-use trial.

    PubMed

    El-Khoury, J; Fishman, J A

    2003-09-01

    Vancomycin-resistant Enterococcus faecium (VRE) is increasing in incidence in solid organ transplant recipients and has a high (up to 83%) associated mortality rate. Until recently, there have been no consistently effective antimicrobial therapies for VRE infection. Linezolid is a new antibiotic that belongs to the class of oxazolidinones approved by the FDA for the treatment of VRE infections, including those with bacteremia. Here, we report the experience with linezolid in an open-label, compassionate-use trial at 53 US centers for the treatment of documented VRE infections in patients with solid organ transplants. Eighty-five patients with solid organ transplants and documented VRE infections were studied. Blood cultures were positive for VRE in 43 patients, while 42 patients had other, non-rectal, sites of infection. Fifty-three patients responded well to treatment, with clinical resolution of the infection (62.4% survival rate). Of these, 47 had documented negative cultures post therapy. The mean duration of therapy for cured patients was 23.5 days. Thirty-two (37.6%) patients died, 28 due to sepsis and organ failure (32.9% failure rate), and 4 due to unrelated causes. Mortality rates for patients with bacteremia were comparable to mortality rates observed with patients who had positive cultures from other sites. Adverse reactions to linezolid included thrombocytopenia (4.7%), decreased leukocyte count (3.5%), and an increase in blood pressure (1.2%), none of which led to discontinuation of therapy. Linezolid appears to be a safe and effective treatment option for VRE, even in the presence of bacteremia, and may lead to decreased mortality in solid organ transplant recipients with VRE infection.

  7. The Enterococcus faecium Enterococcal Biofilm Regulator, EbrB, Regulates the esp Operon and Is Implicated in Biofilm Formation and Intestinal Colonization

    PubMed Central

    Top, Janetta; Paganelli, Fernanda L.; Zhang, Xinglin; van Schaik, Willem; Leavis, Helen L.; van Luit-Asbroek, Miranda; van der Poll, Tom; Leendertse, Masja; Bonten, Marc J. M.; Willems, Rob J. L.

    2013-01-01

    Nowadays, Enterococcus faecium is one of the leading nosocomial pathogens worldwide. Strains causing clinical infections or hospital outbreaks are enriched in the enterococcal surface protein (Esp) encoding ICEEfm1 mobile genetic element. Previous studies showed that Esp is involved in biofilm formation, endocarditis and urinary tract infections. In this study, we characterized the role of the putative AraC type of regulator (locus tag EfmE1162_2351), which we renamed ebrB and which is, based on the currently available whole genome sequences, always located upstream of the esp gene, and studied its role in Esp surface exposure during growth. A markerless deletion mutant of ebrB resulted in reduced esp expression and complete abolishment of Esp surface exposure, while Esp cell-surface exposure was restored when this mutant was complemented with an intact copy of ebrB. This demonstrates a role for EbrB in esp expression. However, during growth, ebrB expression levels did not change over time, while an increase in esp expression at both RNA and protein level was observed during mid-log and late-log phase. These results indicate the existence of a secondary regulation system for esp, which might be an unknown quorum sensing system as the enhanced esp expression seems to be cell density dependent. Furthermore, we determined that esp is part of an operon of at least 3 genes putatively involved in biofilm formation. A semi-static biofilm model revealed reduced biofilm formation for the EbrB deficient mutant, while dynamics of biofilm formation using a flow cell system revealed delayed biofilm formation in the ebrB mutant. In a mouse intestinal colonization model the ebrB mutant was less able to colonize the gut compared to wild-type strain, especially in the small intestine. These data indicate that EbrB positively regulates the esp operon and is implicated in biofilm formation and intestinal colonization. PMID:23741484

  8. Biochemical and genetic characterization of enterocin P, a novel sec-dependent bacteriocin from Enterococcus faecium P13 with a broad antimicrobial spectrum.

    PubMed

    Cintas, L M; Casaus, P; Håvarstein, L S; Hernández, P E; Nes, I F

    1997-11-01

    Enterocin P is a new bacteriocin produced by Enterococcus faecium P13 isolated from a Spanish dry-fermented sausage. Enterocin P inhibited most of tested spoilage and food-borne gram-positive pathogenic bacteria, such as Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens, and Clostridium botulinum. Enterocin P is produced during growth in MRS broth from 16 to 45 degrees C; it is heat resistant (60 min at 100 degrees C; 15 min at 121 degrees C) and can withstand exposure to pH between 2.0 and 11.0, freeze-thawing, lyophilization, and long-term storage at 4 and -20 degrees C. The bacteriocin was purified to homogeneity by ammonium sulfate precipitation, gel filtration, cation-exchange, hydrophobic-interaction, and reverse-phase liquid chromatography. The sequence of 43 amino acids of the N terminus was obtained by Edman degradation. DNA sequencing analysis of a 755-bp region revealed the presence of two consecutive open reading frames (ORFs). The first ORF encodes a 71-amino-acid protein containing a hydrophobic N-terminal sec-dependent leader sequence of 27 amino acids followed by the amino acid sequence corresponding to the purified and sequenced enterocin P. The bacteriocin is apparently synthesized as a prepeptide that is cleaved immediately after the Val-Asp-Ala residues (positions -3 to -1), resulting in the mature bacteriocin consisting of 44 amino acids, and with a theoretical molecular weight of 4,493. A second ORF, encoding a putative immunity protein composed of 88 amino acids with a calculated molecular weight of 9,886, was found immediately downstream of the enterocin P structural gene. Enterocin P shows a strong antilisterial activity and has the consensus sequence found in the pediocin-like bacteriocins; however, enterocin P is processed and secreted by the sec-dependent pathway.

  9. Systemic and local bactericidal potentiality in late lactation Holstein-Friesian cows following a combined antibiotics and Enterococcus faecium SF68 dry-cow treatment.

    PubMed

    Tiantong, Attapol; Piamya, Piya; Chen, Shuen-Ei; Liu, Wen-Bor; Chang, Fang-Yu; Lin, Pei-Chi; Nagahata, Hajime; Chang, Chai-Ju

    2015-08-01

    Antibiotic dry-cow treatment contributes a major part to the total use of antibiotics in dairy herds. Enterococcus faecium strain SF68 (SF68) was of human origin but has been authorized in EU as probiotic feed additive. In the present study, one of the front and rear quarters of twelve late lactation Holstein-Friesian cows were infused once with a commercial antibiotic dry-cow formula (antibiotics quarter) on the first milk-stasis day (d 1), when the contrallateral quarters were infused with 5 x 10(8)-CFU SF68 plus half-dose antibiotic dry-cow formula (SF68/antibiotics quarter) meanwhile. Gelatinase level and cellular reactive oxygen species (ROS) production capacity were measured for blood and quarter secretion. The results showed that the count of blood total leukocytes minorly decreased on d 3 only but the microscopic somatic cell count (MSCC) continuously increased up to d 7, especially in SF68/antibiotics quarters. Plasma level of gelatinase A remained similar up to d 7 but gelatinase B was not detectable in plasma throughout the study. The level of gelatinase A in quarter secretion increased up to d 7 but gelatinase B increased even more drastically, especially in SF68/antibiotics quarters. The ROS production capacity of blood leukocytes increased temporarily only on d 3, but that of milk cells continuously increased up to d 7, especially in SF68/antitiotics quarters. Overall, late lactation Holstein-Friesian cows were systemically adaptable to the combined antibiotics and SF68 dry-cow treatment, while the local bactericidal potentiality in mammary gland was actively responsive to additional SF68 intramammary treatment.

  10. Effect of Vancomycin, Tylosin, and Chlortetracycline on Vancomycin-Resistant Enterococcus faecium Colonization of Broiler Chickens During Grow-Out.

    PubMed

    Hume, Michael E; Donskey, Curtis J

    2017-01-27

    Broiler chickens may serve as reservoirs for human colonization by vancomycin-resistant Enterococcus (VRE). We examined the effects of vancomycin and two commonly used antimicrobial feed additives on VRE colonization in broiler chickens during grow-out. Chicks received unsupplemented feed or feed containing vancomycin, chlortetracycline, or tylosin from day of hatch to grow-out at 6 weeks. At 3 days of age, chicks received by crop gavage 10(7) colony-forming units (CFUs) of a human or poultry VRE isolate. Cecal contents were monitored weekly for VRE, short-chain fatty acids (SCFAs), and bacterial denaturing gradient gel electrophoresis (DGGE) profile methods. Vancomycin promoted persistent and high-level colonization with human- and poultry-derived VRE to grow-out in comparison with controls, while treatment with chlortetracycline and tylosin did not. Colonization by the poultry isolate in control, chlortetracycline, and tylosin groups persisted throughout the grow-out period with low concentrations present at 6 weeks, whereas the human isolate decreased to an undetectable level by week 6. Vancomycin resulted in significant reductions in cecal acetic acid and butyric acid in comparison with controls, but chlortetracycline and tylosin did not. DGGE profiles contained two main clusters with all vancomycin profiles in a smaller cluster and all other profiles in a larger cluster. These results demonstrate that vancomycin, but not chlortetracycline or tylosin, disrupted the indigenous microbiota and SCFA patterns of broiler chickens and promoted colonization by VRE.

  11. Cloning, purification, crystallization and preliminary crystallographic analysis of SecA from Enterococcus faecalis

    SciTech Connect

    Meining, Winfried; Scheuring, Johannes; Fischer, Markus; Weinkauf, Sevil

    2006-06-01

    SecA ATPase from E. faecalis has been cloned, overexpressed, purified and crystallized. Crystals belong to space group C2 and diffract to 2.4 Å resolution. The gene coding for SecA from Enterococcus faecalis was cloned and overexpressed in Escherichia coli. In this protein, the lysine at position 6 was replaced by an asparagine in order to reduce sensitivity towards proteases. The modified protein was purified and crystallized. Crystals diffracting to 2.4 Å resolution were obtained using the vapour-diffusion technique. The crystals belong to the monoclinic space group C2, with unit-cell parameters a = 203.4, b = 49.8, c = 100.8 Å, α = γ = 90.0, β = 119.1°. A selenomethionine derivative was prepared and is currently being tested in crystallization trials.

  12. Purification, crystallization and preliminary X-ray analysis of Enterococcus faecium aminoglycoside-2′′-phosphotransferase-Ib [APH(2′′)-Ib

    SciTech Connect

    Walanj, Rupa; Young, Paul; Baker, Heather M.; Baker, Edward N.; Metcalf, Peter; Chow, Joseph W.; Lerner, Stephen; Vakulenko, Sergei; Smith, Clyde A.

    2005-04-01

    APH(2′′)-Ib is an enzyme responsible for high-level gentamicin resistance in E. faecium isolates. Native crystals of this enzyme have been prepared and preliminary X-ray diffraction experiments have been undertaken. Bacterial resistance to the aminoglycoside antibiotics is primarily the result of deactivation of the drugs. Three families of enzymes are responsible for this activity, with one such family being the aminoglycoside phosphotransferases (APHs). The gene encoding one of these enzymes, APH(2′′)-Ib, has been cloned and the protein (comprising 299 amino-acid residues) expressed in Escherichia coli, purified and crystallized in the presence of 16%(w/v) PEG 3350 and gentamicin. The crystals belong to the monoclinic space group P2{sub 1}, with approximate unit-cell parameters a = 79.7, b = 58.8, c = 81.4 Å, β = 98.4°, and preliminary X-ray diffraction analysis is consistent with the presence of two molecules in the asymmetric unit. Synchrotron diffraction data to approximately 2.65 Å resolution were collected from a native APH(2′′)-Ib crystal at beamline BL9-2 at SSRL (Stanford, CA, USA). Selenium-substituted crystals have also been produced and structure determination is proceeding.

  13. Identification and phenotypic characterization of a second collagen adhesin, Scm, and genome-based identification and analysis of 13 other predicted MSCRAMMs, including four distinct pilus loci, in Enterococcus faecium

    PubMed Central

    Sillanpää, Jouko; Nallapareddy, Sreedhar R.; Prakash, Vittal P.; Qin, Xiang; Hook, Magnus; Weinstock, George M.; Murray, Barbara E.

    2009-01-01

    SUMMARY Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about pathogenic determinants of this organism. We have previously identified a cell wall anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad spectrum binding to extracellular matrix proteins. Here, we analyzed the draft genome of strain TX0016 for potential MSCRAMMs (microbial surface component recognizing adhesive matrix molecules). Genome-based bioinformatics identified 22 predicted cell wall anchored E. faeciumsurface proteins (Fms) of which 15 (including Acm) have typical characteristics of MSCRAMMs including predicted folding into a modular architecture with multiple immunoglobulin-like domains. Functional characterization of one (Fms10, redesignated Scm for second collagen adhesin of E. faeciu m) revealed that recombinant Scm65 (A- and B-domains) and Scm36 (A-domain) bound efficiently to collagen type V in a concentration dependent manner, bound considerably less to collagen type I and fibrinogen, and differed from Acm in their binding specificities to collagen types IV and V. Results from far-UV circular dichroism of recombinant Scm36 and of Acm37 indicated that these proteins are rich in β-sheets, supporting our folding predictions. Whole-cell ELISA and FACS analyses unambiguously demonstrated surface expression of Scm in most E. faecium isolates. Strikingly, 11 of the 15 predicted MSCRAMMs clustered in four loci, each with a class C sortase gene; 9 of these showed similarity to Enterococcus faecalis Ebp pilus subunits and also contained motifs essential for pilus assembly. Antibodies against one of the predicted major pilus proteins, Fms9 (redesignated as EbpCfm), detected a “ladder” pattern of high-molecular weight protein bands in a Western blot

  14. Determination of the nucleotide sequence of the 23S ribosomal RNA and flanking spacers of an Enterococcus faecium strain, reveals insertion-deletion events in the ribosomal spacer 1 of enterococci.

    PubMed

    Naimi, A; Beck, G; Monique, M; Lefèbvre, G; Branlanti, C

    1999-02-01

    The usefulness of 16S-23S (ITS1) and 23S-5S (ITS2) ribosomal spacer nucleotide sequence determination, as a complementary approach to the biochemical tests traditionally used for enterococcal species identification, is shown by its application to the identification of a strain, E27, isolated from a natural bacteria mixture used for cheese production. Using combined approaches we showed, unambiguously, that strain E27 belongs to the Enterococcus faecium species. However, its ITS1 region has an interesting peculiarity. In our previous study of ITS1s from various enterococcal species (NAIMI et al., 1997, Microbiology 143, 823-834), the ITS1s of the two E. faecium strains studied, were found to contain an additional 115-nt long stem-loop structure as compared to the ITS1s of other enterococci, only one out of the 3 ITS1s of E. hirae ATCC 9790, was found to contain a similar 107-nt long stem-loop structure. The ITS1 of strain E27 is 100% identical to that of E. faecium ATCC 19434T, except that the 115-nt additional fragment is absent. This strongly suggests the existence of lateral DNA transfer or DNA recombination events at a hot spot position of the ITS1s from E. faecium and E. hirae. Small and large ITS1 nucleotide sequence determination for strain E27 generalized the notion of two kinds of ITSs in enterococci: one with a tRNA(Ala) gene, one without tRNA gene. To complete strain E27 characterization, its 23S rRNA sequence was established. This is the first complete 23S rRNA nucleotide sequence determined for an enterococcal species.

  15. Involvement of the Eukaryote-Like Kinase-Phosphatase System and a Protein That Interacts with Penicillin-Binding Protein 5 in Emergence of Cephalosporin Resistance in Cephalosporin-Sensitive Class A Penicillin-Binding Protein Mutants in Enterococcus faecium

    PubMed Central

    Desbonnet, Charlene; Tait-Kamradt, Amelia; Garcia-Solache, Monica; Dunman, Paul; Coleman, Jeffrey; Arthur, Michel

    2016-01-01

    ABSTRACT The intrinsic resistance of Enterococcus faecium to ceftriaxone and cefepime (here referred to as “cephalosporins”) is reliant on the presence of class A penicillin-binding proteins (Pbps) PbpF and PonA. Mutants lacking these Pbps exhibit cephalosporin susceptibility that is reversible by exposure to penicillin and by selection on cephalosporin-containing medium. We selected two cephalosporin-resistant mutants (Cro1 and Cro2) of class A Pbp-deficient E. faecium CV598. Genome analysis revealed changes in the serine-threonine kinase Stk in Cro1 and a truncation in the associated phosphatase StpA in Cro2 whose respective involvements in resistance were confirmed in separate complementation experiments. In an additional effort to identify proteins linked to cephalosporin resistance, we performed tandem affinity purification using Pbp5 as bait in penicillin-exposed E. faecium; these experiments yielded a protein designated Pbp5-associated protein (P5AP). Transcription of the P5AP gene was increased after exposure to penicillin in wild-type strains and in Cro2 and suppressed in Cro2 complemented with the wild-type stpA. Transformation of class A Pbp-deficient strains with the plasmid-carried P5AP gene conferred cephalosporin resistance. These data suggest that Pbp5-associated cephalosporin resistance in E. faecium devoid of typical class A Pbps is related to the presence of P5AP, whose expression is influenced by the activity of the serine-threonine phosphatase/kinase system. PMID:27048803

  16. Cloning and sequence analysis of the muramidase-2 gene from Enterococcus hirae.

    PubMed Central

    Chu, C P; Kariyama, R; Daneo-Moore, L; Shockman, G D

    1992-01-01

    Extracellular muramidase-2 of Enterococcus hirae ATCC 9790 was purified to homogeneity by substrate binding, guanidine-HCl extraction, and reversed-phase chromatography. A monoclonal antibody, 2F8, which specifically recognizes muramidase-2, was used to screen a genomic library of E. hirae ATCC 9790 DNA in bacteriophage lambda gt11. A positive phage clone containing a 4.5-kb DNA insert was isolated and analyzed. The EcoRI-digested 4.5-kb fragment was cut into 2.3-, 1.0-, and 1.5-kb pieces by using restriction enzymes KpnI, Sau3AI, and PstI, and each fragment was subcloned into plasmid pJDC9 or pUC19. The nucleotide sequence of each subclone was determined. The sequence data indicated an open reading frame encoding a polypeptide of 666 amino acid residues, with a calculated molecular mass of 70,678 Da. The first 24 N-terminal amino acids of purified extracellular muramidase-2 were in very good agreement with the deduced amino acid sequence after a 49-amino-acid putative signal sequence. Analysis of the deduced amino acid sequence showed the presence at the C-terminal region of the protein of six highly homologous repeat units separated by nonhomologous intervening sequences that are highly enriched in serine and threonine. The overall sequence showed a high degree of homology with a recently cloned Streptococcus faecalis autolysin. Images PMID:1347040

  17. Effect of sausage ingredients and additives on the production of enterocin A and B by Enterococcus faecium CTC492. Optimization of in vitro production and anti-listerial effect in dry fermented sausages.

    PubMed

    Aymerich, T; Artigas, M G; Garriga, M; Monfort, J M; Hugas, M

    2000-04-01

    Enterocin A and B in Enterococcus faecium CTC492 were co-induced by the different factors assayed in this study (r = 0.93) and followed primary metabolic kinetics. Enterocin production was significantly inhibited by sausage ingredients and additives, with the exception of nitrate. The addition of sodium chloride and pepper decreased production 16-fold. The temperature and pH influenced enterocin production, with optima between 25 and 35 degrees C, and from 6.0 to 7.5 of initial pH. The maximum activity was achieved, under favourable growth conditions, with MRS supplemented with sucrose (2%) plus glucose (0.25%) and Tween-80 (1%). MRS concentration, NaCl plus pepper addition, absence of Tween-80 in the growth medium, incubation at 45 degrees C and an initial pH under 5.5 were detrimental to bacteriocin production. Stress conditions did not favour enterocin production. Desadsorption was Tween-dependent. Enterocin A activity in the crude extracts stored at -80 degrees C was better preserved than enterocin B (when tested against their specific indicator strain), but anti-listerial activity remained intact. Applied as anti-listerial additives in dry fermented sausages, enterocins significantly diminished Listeria counts by 1. 13 log (P < 0.001), while Enterococcus faecium CTC492 added as starter culture did not significantly reduce Listeria counts (P > 0. 1) compared with the standard starter culture (Bac-). Enterocins A and B could be considered as extra biopreservative hurdles for listeria prevention in dry fermented sausages.

  18. High-level ciprofloxacin resistance from point mutations in gyrA and parC confined to global hospital-adapted clonal lineage CC17 of Enterococcus faecium.

    PubMed

    Leavis, Helen L; Willems, Rob J L; Top, Janetta; Bonten, Marc J M

    2006-03-01

    To substantiate a common genetic background of ciprofloxacin-resistant Enterococcus faecium, 32 ciprofloxacin-resistant (Cip(r)) and 31 ciprofloxacin-susceptible (Cip(s)) isolates from outbreaks, clinical infections, surveillances, and animals from 10 different countries were genotyped by multilocus sequence typing. Additionally, susceptibilities to ampicillin and vancomycin and the presence of esp were determined and the quinolone resistance-determining regions of parC, gyrA, parB, and gyrE were sequenced. High-level Cip(r) (MIC > or = 64 microg/ml) due to point mutations in the quinolone resistance-determining region was unique to a distinct hospital-adapted genetic complex in E. faecium, previously designated CC17. Low-level Cip(r) (MIC = 4 microg/ml) in non-CC17 strains is not attributable to point mutations in any subunit of the topoisomerase genes, and the mechanism of resistance remains unclear. Acquisition of mutations in parC and gyrA, leading to high-level Cip(r), is, in addition to ampicillin resistance and the presence of a putative pathogenicity island, another cumulative step in hospital adaptation of CC17.

  19. Local Genetic Patterns within a Vancomycin-Resistant Enterococcus faecalis Clone Isolated in Three Hospitals in Portugal

    PubMed Central

    Novais, Carla; Coque, Teresa M.; Sousa, João Carlos; Baquero, Fernando; Peixe, Luisa

    2004-01-01

    Eight pulsed-field gel electrophoresis subtypes and six Tn1546 variants were identified among Enterococcus faecalis isolates of a single clone recovered in three geographically separate Portuguese hospitals. Some clonal subtypes were found in particular hospitals, and Tn1546 variants were either widespread or confined to some of them. We also report on the first Tn1546 transposon containing an ISEf1 insertion. PMID:15328141

  20. Activity of daptomycin or linezolid in combination with rifampin or gentamicin against biofilm-forming Enterococcus faecalis or E. faecium in an in vitro pharmacodynamic model using simulated endocardial vegetations and an in vivo survival assay using Galleria mellonella larvae.

    PubMed

    Luther, Megan K; Arvanitis, Marios; Mylonakis, Eleftherios; LaPlante, Kerry L

    2014-08-01

    Enterococci are the third most frequent cause of infective endocarditis. A high-inoculum stationary-phase in vitro pharmacodynamic model with simulated endocardial vegetations was used to simulate the human pharmacokinetics of daptomycin at 6 or 10 mg/kg of body weight/day or linezolid at 600 mg every 12 h (q12h), alone or in combination with gentamicin at 1.3 mg/kg q12h or rifampin at 300 mg q8h or 900 mg q24h. Biofilm-forming, vancomycin-susceptible Enterococcus faecalis and vancomycin-resistant Enterococcus faecium (vancomycin-resistant enterococcus [VRE]) strains were tested. At 24, 48, and 72 h, all daptomycin-containing regimens demonstrated significantly more activity (decline in CFU/g) than any linezolid-containing regimen against biofilm-forming E. faecalis. The addition of gentamicin to daptomycin (at 6 or 10 mg/kg) in the first 24 h significantly improved bactericidal activity. In contrast, the addition of rifampin delayed the bactericidal activity of daptomycin against E. faecalis, and the addition of rifampin antagonized the activities of all regimens against VRE at 24 h. Also, against VRE, the addition of gentamicin to linezolid at 72 h improved activity and was bactericidal. Rifampin significantly antagonized the activity of linezolid against VRE at 72 h. In in vivo Galleria mellonella survival assays, linezolid and daptomycin improved survival. Daptomycin at 10 mg/kg improved survival significantly over that with linezolid against E. faecalis. The addition of gentamicin improved the efficacy of daptomycin against E. faecalis and those of linezolid and daptomycin against VRE. We conclude that in enterococcal infection models, daptomycin has more activity than linezolid alone. Against biofilm-forming E. faecalis, the addition of gentamicin in the first 24 h causes the most rapid decline in CFU/g. Of interest, the addition of rifampin decreased the activity of daptomycin against both E. faecalis and VRE.

  1. Complete Sequence of the Enterocin Q-Encoding Plasmid pCIZ2 from the Multiple Bacteriocin Producer Enterococcus faecium L50 and Genetic Characterization of Enterocin Q Production and Immunity

    PubMed Central

    Criado, Raquel; Diep, Dzung B.; Aakra, Ågot; Gutiérrez, Jorge; Nes, Ingolf F.; Hernández, Pablo E.; Cintas, Luis M.

    2006-01-01

    The locations of the genetic determinants for enterocin L50 (EntL50A and EntL50B), enterocin Q (EntQ), and enterocin P (EntP) in the multiple bacteriocin producer Enterococcus faecium strain L50 were determined. These bacteriocin genes occur at different locations; entL50AB (encoding EntL50A and EntL50B) are on the 50-kb plasmid pCIZ1, entqA (encoding EntQ) is on the 7.4-kb plasmid pCIZ2, and entP (encoding EntP) is on the chromosome. The complete nucleotide sequence of pCIZ2 was determined to be 7,383 bp long and contains 10 putative open reading frames (ORFs) organized in three distinct regions. The first region contains three ORFs: entqA preceded by two divergently oriented genes, entqB and entqC. EntqB shows high levels of similarity to bacterial ATP-binding cassette (ABC) transporters, while EntqC displays no significant similarity to any known protein. The second region encompasses four ORFs (orf4 to orf7), and ORF4 and ORF5 display high levels of similarity to mobilization proteins from E. faecium and Enterococcus faecalis. In addition, features resembling a transfer origin region (oriT) were found in the promoter area of orf4. The third region contains three ORFs (orf8 to orf10), and ORF8 and ORF9 exhibit similarity to the replication initiator protein RepE from E. faecalis and to RepB proteins, respectively. To clarify the minimum requirement for EntQ synthesis, we subcloned and heterologously expressed a 2,371-bp fragment from pCIZ2 that encompasses only the entqA, entqB, and entqC genes in Lactobacillus sakei, and we demonstrated that this fragment is sufficient for EntQ production. Moreover, we also obtained experimental results indicating that EntqB is involved in ABC transporter-mediated EntQ secretion, while EntqC confers immunity to this bacteriocin. PMID:17021217

  2. Efficacy of vacuum steam pasteurization for inactivation of Salmonella PT 30, Escherichia coli O157:H7 and Enterococcus faecium on low moisture foods.

    PubMed

    Shah, Manoj K; Asa, Gladys; Sherwood, Julie; Graber, Kari; Bergholz, Teresa M

    2017-03-06

    Low moisture foods such as nuts, spices, and seeds have been implicated in several outbreaks due to Salmonella or E. coli O157:H7 contamination. Such foods may be consumed raw, and can be used as ingredients in other food products. While numerous thermal inactivation studies have been conducted for Salmonella on nuts, studies on other seeds and grains are minimal. Product water activity can influence the thermal resistance of pathogens, where thermal resistance increases as water activity decreases, leading to a requirement for higher temperatures and longer exposure times to achieve significant reduction of pathogen numbers. Vacuum steam pasteurization uses steam under vacuum, which can be operated at temperatures above and below 100°C. The objective of this study was to determine the efficacy of vacuum steam pasteurization for inactivation of pathogens on whole flaxseed, quinoa, sunflower kernels, milled flaxseed and whole black peppercorns. The use of E. faecium as a potential surrogate for Salmonella and E. coli O157:H7 in vacuum steam pasteurization was also evaluated. Pasteurization for 1min at 75°C yielded average log reductions of 5.48±1.22, 5.71±0.40 and 5.23±0.61 on flaxseed, 4.29±0.92, 5.89±0.26 and 2.39±0.83 on quinoa, and 4.01±0.74, 5.40±0.83 and 2.99±0.92 on sunflower kernels for Salmonella PT 30, E. coli O157:H7 and E. faecium, respectively. Similarly, on milled flaxseed and black peppercorns average log reductions of 3.02±0.79 and 6.10±0.64CFU/g were observed for Salmonella PT 30 after 1min of treatment at 75°C but, on average, >6.0 log reductions were observed after pasteurization at 85°C. Our data demonstrate that vacuum steam pasteurization can be effectively used to reduce pathogens on these low moisture foods at temperature as low as 75 and 85°C, and that E. faecium may be used as a potential surrogate for Salmonella PT 30 and E. coli O157:H7.

  3. Immunochemical Characterization of Temperature-Regulated Production of Enterocin L50 (EntL50A and EntL50B), Enterocin P, and Enterocin Q by Enterococcus faecium L50▿

    PubMed Central

    Criado, Raquel; Gutiérrez, Jorge; Martín, María; Herranz, Carmen; Hernández, Pablo E.; Cintas, Luis M.

    2006-01-01

    Polyclonal antibodies with specificity for enterocin L50A (EntL50A), enterocin L50B (EntL50B), and enterocin Q (EntQ) produced by Enterococcus faecium L50 have been generated by immunization of rabbits with chemically synthesized peptides derived from the C terminus of EntL50A (LR1) and EntL50B (LR2) and from the complete enterocin Q (EntQ) conjugated to the carrier protein keyhole limpet hemocyanin (KLH). The sensitivity and specificity of these antibodies were evaluated by a noncompetitive indirect enzyme-linked immunosorbent assay (NCI-ELISA) and a competitive indirect ELISA (CI-ELISA). The NCI-ELISA was valuable for detecting anti-EntL50A-, anti-EntL50B-, and anti-EntQ-specific antibodies in the sera of the LR1-KLH-, LR2-KLH-, and EntQ-KLH-immunized animals, respectively. Moreover, these antibodies and those specific for enterocin P (EntP) obtained in a previous work (J. Gutiérrez, R. Criado, R. Citti, M. Martín, C. Herranz, M. F. Fernández, L. M. Cintas, and P. E. Hernández, J. Agric. Food Chem. 52:2247-2255, 2004) were used in an NCI-ELISA to detect and quantify the production of EntL50A, EntL50B, EntP, and EntQ by the multiple-bacteriocin producer E. faecium L50 grown at different temperatures (16 to 47°C). Our results show that temperature has a strong influence on bacteriocin production by this strain. EntL50A and EntL50B are synthesized at 16 to 32°C, but production becomes negligible when the growth temperature is above 37°C, whereas EntP and EntQ are synthesized at temperatures ranging from 16 to 47°C. Maximum EntL50A and EntL50B production was detected at 25°C, while EntP and EntQ are maximally produced at 37 and 47°C, respectively. The loss of plasmid pCIZ1 (50 kb) and/or pCIZ2 (7.4 kb), encoding EntL50A and EntL50B as well as EntQ, respectively, resulted in a significant increase in production and stability of the chromosomally encoded EntP. PMID:17056686

  4. Fosfomycin Synergy In Vitro with Amoxicillin, Daptomycin, and Linezolid against Vancomycin-Resistant Enterococcus faecium from Renal Transplant Patients with Infected Urinary Stents

    PubMed Central

    Descourouez, Jillian L.; Jorgenson, Margaret R.; Wergin, Justine E.

    2013-01-01

    Fosfomycin is a potential option for vancomycin-resistant enterococcus (VRE) infections despite limited in vitro and clinical data. In this study, 32 VRE isolates from renal transplant patients with urinary stent infections were susceptible to fosfomycin, daptomycin, and linezolid and resistant to amoxicillin, minocycline, and nitrofurantoin based on their MIC50s and MIC90s. Fosfomycin was bacteriostatic at 0.5 to 16× the MIC (32 to 2,048 μg/ml); synergy occurred when fosfomycin was combined with daptomycin (2.8 to 3.9 log10 CFU/ml kill; P < 0.001) or amoxicillin (2.6 to 3.4; P < 0.05). These combinations may be potent options to treat VRE urinary infections pending investigation of clinical efficacy. PMID:23263002

  5. Spread of an Enterococcus faecalis sequence type 6 (CC2) clone in patients undergoing selective decontamination of the digestive tract.

    PubMed

    Muruzábal-Lecumberri, Izaskun; Girbau, Cecilia; Canut, Andrés; Alonso, Rodrigo; Fernández-Astorga, Aurora

    2015-03-01

    Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high-risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD-PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD-PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU.

  6. Antimicrobial resistance profile of Enterococcus spp isolated from food in Southern Brazil

    PubMed Central

    Riboldi, Gustavo Pelicioli; Frazzon, Jeverson; d’Azevedo, Pedro Alves; Frazzon, Ana Paula Guedes

    2009-01-01

    Fifty-six Enterococcus spp. strains were isolated from foods in Southern Brazil, confirmed by PCR and classified as Enterococcus faecalis (27), Enterococcus faecium (23) and Enterococcus spp (6). Antimicrobial susceptibility tests showed resistance phenotypes to a range of antibiotics widely administrated in humans such as gentamycin, streptomycin, ampicillin and vancomycin. PMID:24031330

  7. vanA-containing E. faecium isolates of clonal complex CC17 in clinical and environmental samples in a Tunisian hospital.

    PubMed

    Elhani, Dalèle; Klibi, Naouel; Dziri, Raoudha; Ben Hassan, Meriem; Asli Mohamed, Selim; Ben Said, Laila; Mahjoub, Aouini; Ben Slama, Karim; Jemli, Boutheina; Bellaj, Ridha; Barguellil, Farouk; Torres, Carmen

    2014-05-01

    Twenty-eight vancomycin (VA)-resistant enterococci isolated from different patients (n = 16) and also from the environment (n = 12) were recovered in a Tunisian military hospital during 2012-2013. The mechanisms of resistance to VA and to other antibiotics as well as the presence of esp and hyl virulence genes were determined in these isolates by PCR, being their clonal relationship analyzed by pulsed-field gel electrophoresis (PFGE). VA resistance mechanisms detected were as follows (species-patient/environment): vanA (Enterococcus faecium, 13/5), vanC1 (Enterococcus gallinarum, 3/0), and vanC2 (Enterococcus casseliflavus, 0/7). Most of the VA-resistant enterococci presented a multiresistance phenotype and harbored different resistance genes (erm(B), tet(M), tet(L), ant(6)-Ia, aac(6')-aph(2"), aph(3')-IIIa, and catA). The PFGE revealed the presence of 3 clones (A, B, C) and 1 closely related pattern (A1) among the 13 vanA-containing E. faecium isolates of patients showing 11 of them the A-A1 patterns. The clone A was also detected in all 5 environmental vanA-containing E. faecium isolates. Strains did not contain esp or hyl virulence genes. Multilocus sequence typing was performed in 4 E. faecium isolates representative of the 4 detected pulsotypes (A, A1, B, and C), and 2 different sequence types were identified (ST18 and ST80), both of them included in clonal complex CC17. These strains contained the IS16 element and showed ampicillin and ciprofloxacin resistance. VA resistance could be an emerging problem in Tunisia, and this is one of the first cases described so far in this country.

  8. Global Emergence and Dissemination of Enterococci as Nosocomial Pathogens: Attack of the Clones?

    PubMed Central

    Guzman Prieto, Ana M.; van Schaik, Willem; Rogers, Malbert R. C.; Coque, Teresa M.; Baquero, Fernando; Corander, Jukka; Willems, Rob J. L.

    2016-01-01

    Enterococci are Gram-positive bacteria that are found in plants, soil and as commensals of the gastrointestinal tract of humans, mammals, and insects. Despite their commensal nature, they have also become globally important nosocomial pathogens. Within the genus Enterococcus, Enterococcus faecium, and Enterococcus faecalis are clinically most relevant. In this review, we will discuss how E. faecium and E. faecalis have evolved to become a globally disseminated nosocomial pathogen. E. faecium has a defined sub-population that is associated with hospitalized patients and is rarely encountered in community settings. These hospital-associated clones are characterized by the acquisition of adaptive genetic elements, including genes involved in metabolism, biofilm formation, and antibiotic resistance. In contrast to E. faecium, clones of E. faecalis isolated from hospitalized patients, including strains causing clinical infections, are not exclusively found in hospitals but are also present in healthy individuals and animals. This observation suggests that the division between commensals and hospital-adapted lineages is less clear for E. faecalis than for E. faecium. In addition, genes that are reported to be associated with virulence of E. faecalis are often not unique to clinical isolates, but are also found in strains that originate from commensal niches. As a reflection of more ancient association of E. faecalis with different hosts, these determinants Thus, they may not represent genuine virulence genes but may act as host-adaptive functions that are useful in a variety of intestinal environments. The scope of the review is to summarize recent trends in the emergence of antibiotic resistance and explore recent developments in the molecular epidemiology, population structure and mechanisms of adaptation of E. faecium and E. faecalis. PMID:27303380

  9. Global Emergence and Dissemination of Enterococci as Nosocomial Pathogens: Attack of the Clones?

    PubMed

    Guzman Prieto, Ana M; van Schaik, Willem; Rogers, Malbert R C; Coque, Teresa M; Baquero, Fernando; Corander, Jukka; Willems, Rob J L

    2016-01-01

    Enterococci are Gram-positive bacteria that are found in plants, soil and as commensals of the gastrointestinal tract of humans, mammals, and insects. Despite their commensal nature, they have also become globally important nosocomial pathogens. Within the genus Enterococcus, Enterococcus faecium, and Enterococcus faecalis are clinically most relevant. In this review, we will discuss how E. faecium and E. faecalis have evolved to become a globally disseminated nosocomial pathogen. E. faecium has a defined sub-population that is associated with hospitalized patients and is rarely encountered in community settings. These hospital-associated clones are characterized by the acquisition of adaptive genetic elements, including genes involved in metabolism, biofilm formation, and antibiotic resistance. In contrast to E. faecium, clones of E. faecalis isolated from hospitalized patients, including strains causing clinical infections, are not exclusively found in hospitals but are also present in healthy individuals and animals. This observation suggests that the division between commensals and hospital-adapted lineages is less clear for E. faecalis than for E. faecium. In addition, genes that are reported to be associated with virulence of E. faecalis are often not unique to clinical isolates, but are also found in strains that originate from commensal niches. As a reflection of more ancient association of E. faecalis with different hosts, these determinants Thus, they may not represent genuine virulence genes but may act as host-adaptive functions that are useful in a variety of intestinal environments. The scope of the review is to summarize recent trends in the emergence of antibiotic resistance and explore recent developments in the molecular epidemiology, population structure and mechanisms of adaptation of E. faecium and E. faecalis.

  10. Purification, crystallization and preliminary X-ray analysis of Enterococcus faecium aminoglycoside-2′′-phosphotransferase-Ib [APH(2′′)-Ib

    PubMed Central

    Walanj, Rupa; Young, Paul; Baker, Heather M.; Baker, Edward N.; Metcalf, Peter; Chow, Joseph W.; Lerner, Stephen; Vakulenko, Sergei; Smith, Clyde A.

    2005-01-01

    Bacterial resistance to the aminoglycoside antibiotics is primarily the result of deactivation of the drugs. Three families of enzymes are responsible for this activity, with one such family being the aminoglycoside phosphotransferases (APHs). The gene encoding one of these enzymes, APH(2′′)-Ib, has been cloned and the protein (comprising 299 amino-acid residues) expressed in Escherichia coli, purified and crystallized in the presence of 16%(w/v) PEG 3350 and gentamicin. The crystals belong to the monoclinic space group P21, with approximate unit-cell parameters a = 79.7, b = 58.8, c = 81.4 Å, β = 98.4°, and preliminary X-ray diffraction analysis is consistent with the presence of two molecules in the asymmetric unit. Synchrotron diffraction data to approximately 2.65 Å resolution were collected from a native APH(2′′)-Ib crystal at beamline BL9-2 at SSRL (Stanford, CA, USA). Selenium-substituted crystals have also been produced and structure determination is proceeding. PMID:16511055

  11. Enterococcus faecalis Clones in Poultry and in Humans with Urinary Tract Infections, Vietnam

    PubMed Central

    Poulsen, Louise Ladefoged; Bisgaard, Magne; Son, Nguyen Thai; Trung, Nguyen Vu; An, Hoang Manh

    2012-01-01

    Enterococcus spp. as pathogens have increased, but the sources of infection often remain unclear. To investigate whether poultry might be a reservoir for E. faecalis–associated urinary tract infections (UTIs) in humans, we characterized E. faecalis isolates from patients in Vietnam with UTIs during January 2008–January 2010 and poultry living in close contact with them by multilocus sequence typing (MLST), pulsed-field gel electrophoresis, analysis of antimicrobial drug susceptibility patterns, and sequencing of virulence genes. In 7 (23%) of 31 UTI cases, we detected identical MLST, indistinguishable or closely related pulsed-field gel electrophoresis patterns, and similar antimicrobial drug susceptibility patterns. Isolates from urine and poultry showed identical virulence gene profiles, except for 1 variation, and individual genes showed identical sequences. The homology of isolates from urine and poultry further indicates the zoonotic potential and global spread of E. faecalis sequence type 16, which recently was reported in humans with endocarditis and in pigs in Denmark. PMID:22709904

  12. Functional cloning and expression of emeA, and characterization of EmeA, a multidrug efflux pump from Enterococcus faecalis.

    PubMed

    Lee, Eun-Woo; Chen, Jing; Huda, Md Nazmul; Kuroda, Teruo; Mizushima, Tohru; Tsuchiya, Tomofusa

    2003-02-01

    A fragment of chromosomal DNA from Enterococcus faecalis ATCC 29212 was cloned using Escherichia coli KAM32 host cells lacking major multidrug efflux pumps. E. coli KAM32 cells were sensitive to many antimicrobial agents, and the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetraphenylphosphonium chloride, 4',6-diamidino-2-phenylindole (DAPI), Hoechst 33342, acriflavine, benzalkonium chloride, norfloxacin and ethidium bromide. This suggests that the cloned DNA fragment carries a gene(s) encoding a multidrug efflux pump. Determination of the nucleotide sequence of the cloned DNA revealed a gene designated as emeA. The transformed E. coli cells showed efflux activity of several antimicrobial agents such as DAPI, Hoechst 33342 and acriflavine. Efflux of DAPI via EmeA was strongly inhibited by reserpine.

  13. Different VanA Elements in E. faecalis and in E. faecium Suggest at Least Two Origins of Tn1546 Among VRE in a Brazilian Hospital.

    PubMed

    Merlo, Thaís Panhan; Dabul, Andrei Nicoli Gebieluca; Camargo, Ilana Lopes Baratella Cunha

    2015-06-01

    In 2009 during surveillance in a Brazilian hospital, many patients were confirmed to be colonized by vancomycin-resistant enterococci (VRE) and a few infection cases occurred. Among 14 isolates of Enterococcus faecalis, most had the same pulsotype, virulence profile (agg(+)elrA(+)gelE(+)), and were sequence type (ST)103, indicating dissemination of a clone. The 47 Enterococcus faecium were separated into four pulsotypes, the predominant virulence profile being esp(+)acm(+). All of them harbored the hospital marker IS16, and three randomly chosen isolates were ST412, belonging to the Clonal Complex 17. E. faecalis were all susceptible to penicillin and ampicillin, while all E. faecium were resistant to them. All isolates were susceptible to daptomycin and tigecycline. There were no rep-family genes common to all VRE. The VanA element of all E. faecium lost its left-side inverted repeat (IRL) region and had a specific IS insertion. On the other hand, all E. faecalis presented intact Tn1546. The size of plasmids containing the vanA gene as well as its rep-families varied between and within species. The lack of a vanA plasmid common to all VRE, together with the differences among VanA elements, despite the fact that some patients were colonized by both species during their hospitalization, leads us to suggest at least two different Tn1546 origins.

  14. Antimicrobial activity of Enterococcus faecium L50, a strain producing enterocins L50 (L50A and L50B), P and Q, against beer-spoilage lactic acid bacteria in broth, wort (hopped and unhopped), and alcoholic and non-alcoholic lager beers.

    PubMed

    Basanta, Antonio; Sánchez, Jorge; Gómez-Sala, Beatriz; Herranz, Carmen; Hernández, Pablo E; Cintas, Luis M

    2008-07-31

    Enterococcus faecium L50 produces enterocin L50 (L50A and L50B) (EntL50, EntL50A and EntL50B), enterocin P (EntP) and enterocin Q (EntQ) and displays a broad antimicrobial spectrum against the most relevant beer-spoilage lactic acid bacteria (LAB) (i.e., Lactobacillus brevis and Pediococcus damnosus), which is mainly due to the production of EntL50 (EntL50A and EntL50B). Bacteriocin assays using in vitro-synthesized EntL50 (EntL50A and EntL50B) showed that both individual peptides possess antimicrobial activity on their own, EntL50A being the most active, but when the two peptides were combined a synergistic effect was observed. The only virulence genes detected in E. faecium L50 were efaAfm (cell wall adhesin) and ccf (sex pheromone), and this strain was susceptible to most clinically relevant antibiotics. E. faecium L50 survived but did not grow nor showed antimicrobial activity in hopped and unhopped wort, and alcoholic (1 and 5% ethanol, v/v) and non-alcoholic (0% ethanol, v/v) commercial lager beers. However, when unhopped wort was supplemented with 50% (v/v) MRS broth, E. faecium L50 grew and exerted antimicrobial activity similarly as in MRS broth. The enterocins produced by this strain were bactericidal (5 log decrease) against P. damnosus and Lb. brevis in a dose- and substrate-dependent manner when challenged in MRS broth, wort (hopped and unhopped), and alcoholic (1 and 5% ethanol, v/v) and non-alcoholic (0% ethanol, v/v) lager beers at 32 degrees C, and no bacterial resistances were detected even after incubation for 6-15 days. The enterocins in wort and lager beer (5% ethanol, v/v) withstood the heat treatments commonly employed in the brewing industry during mashing, wort boiling, fermentation, and pasteurization, and retained most of their antimicrobial activity in lager beer (5% ethanol, v/v) after long-term storage at 8 and 25 degrees C.

  15. Molecular characterization and antibiotic resistance of Enterococcus species from gut microbiota of Chilean Altiplano camelids

    PubMed Central

    Guerrero-Olmos, Katheryne; Báez, John; Valenzuela, Nicomédes; Gahona, Joselyne; del Campo, Rosa; Silva, Juan

    2014-01-01

    Background Enterococcus is one of the major human pathogens able to acquire multiple antibiotic-resistant markers as well as virulence factors which also colonize remote ecosystems, including wild animals. In this work, we characterized the Enterococcus population colonizing the gut of Chilean Altiplano camelids without foreign human contact. Material and methods Rectal swabs from 40 llamas and 10 alpacas were seeded in M-Enterococcus agar, and we selected a total of 57 isolates. Species identification was performed by biochemical classical tests, semi-automated WIDER system, mass spectrometry analysis by MALDI-TOF (matrix-assisted laser desorption/ionization with a time-of-flight mass spectrometer), and, finally, nucleotide sequence of internal fragments of the 16S rRNA, rpoB, pheS, and aac(6)-I genes. Genetic diversity was measured by pulsed field gel electrophoresis (PFGE)-SmaI, whereas the antibiotic susceptibility was determined by the WIDER system. Carriage of virulence factors was explored by polymerase chain reaction (PCR). Results Our results demonstrated that the most prevalent specie was Enterococcus hirae (82%), followed by other non–Enterococcus faecalis and non–Enterococcus faecium species. Some discrepancies were detected among the identification methods used, and the most reliable were the rpoB, pheS, and aac(6)-I nucleotide sequencing. Selected isolates exhibited susceptibility to almost all studied antibiotics, and virulence factors were not detected by PCR. Finally, some predominant clones were characterized by PFGE into a diverse genetic background. Conclusion Enterococcus species from the Chilean camelids’ gut microbiota were different from those adapted to humans, and they remained free of antibiotic resistance mechanisms as well as virulence factors. PMID:25405007

  16. Inducer bacteria, unique signal peptides and low nutrient media stimulate in-vitro bacteriocin production by Lactobacillus spp. and Enterococcus spp. strains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacteriocins (BCN) provide promising potential to control bacterial infections in a variety of applications. We previously reported three Type IIa BCN produced by Lactobacillus salivarius B-30514 (OR-7), Enterococcus durans/faecium/hirae B-30745 (E 760) and Enterococcus faecium B-30746 (E 50-52). ...

  17. Population biology of Gram-positive pathogens: high-risk clones for dissemination of antibiotic resistance

    PubMed Central

    Willems, Rob J. L.; Hanage, William P; Bessen, Debra E.; Feil, Edward J.

    2011-01-01

    Infections caused by multi-resistant Gram positive bacteria represent a major health burden in the community as well as in hospitalized patients. Staphylococcus aureus, Enterococcus faecalis and Enterococcus faecium are well-known pathogens of hospitalized patients, frequently linked with resistance against multiple antibiotics, compromising effective therapy. Streptococcus pneumoniae and Streptococcus pyogenes are important pathogens in the community and S. aureus has recently emerged as an important community-acquired pathogen. Population genetic studies reveal that recombination prevails as a driving force of genetic diversity in E. faecium, E. faecalis, S. pneumoniae, and S. pyogenes and thus, these species are weakly clonal. Although recombination has a relatively modest role driving the genetic variation of the core genome of S. aureus, the horizontal acquistion of resistance and virulence genes plays a key role in the emergence of new clinically relevant clones in this species. In this review we discuss the population genetics of E. faecium, E. faecalis, S. pneumoniae, S. pyogenes, and S. aureus. Knowledge of the population structure of these pathogens is not only highly relevant for (molecular) epidemiological research but also for identifying the genetic variation that underlies changes in clinical behaviour, to improve our understanding of the pathogenic behaviour of particular clones and to identify novel targets for vaccines or immunotherapy. PMID:21658083

  18. Impact of the probiotic bacteria Enterococcus faecium NCIMB 10415 (SF68) and Bacillus cereus var. toyoi NCIMB 40112 on the development of serum IgG and faecal IgA of sows and their piglets.

    PubMed

    Scharek, Lydia; Guth, Jana; Filter, Matthias; Schmidt, Michael F G

    2007-08-01

    To examine the influence of two different probiotic bacteria on the humoral immune system of swine, two animal studies were carried out with sows and their litters. The sows' feed was supplemented with either Enterococcusfaecium NCIMB 10415 (SF68) or Bacillus cereus var. toyoi NCIMB 40112 beginning early in pregnancy. The total IgA content in the faeces as well as the total IgG concentration in the blood of the sows was recorded before and after weaning. The same parameters were determined in the blood and faeces of the piglets. In sows, only feed supplementation with B. cereus led to a clear increase in faecal IgA. Serum IgG levels were not significantly affected by any probiotic feeding in sows. In piglets, the group that was fed B. cereus showed significantly higher faecal IgA levels shortly before weaning, whereas in the E. faecium group, a significant decrease in IgA levels was observed one week after weaning. In both probiotic fed groups the post-weaning IgG levels were significantly decreased compared to the respective control groups. We conclude that B. cereus var. toyoi feed supplementation led to an increased intestinal IgA secretion both in sows and piglets. This effect could be related to a more successful mucosal defence which in turn led to a lower level in systemic IgG production in piglets after weaning.

  19. [Infections caused by multi-resistant Gram-positive bacteria (Staphylococcus aureus and Enterococcus spp.)].

    PubMed

    Cantón, Rafael; Ruiz-Garbajosa, Patricia

    2013-10-01

    Methicillin -resistant Staphylocccus aureus (MRSA) and multirresistant entorococci are still problematic in nosocomial infections and new challenges have emerged for their containment. MRSA has increased the multiresistant profile; it has been described vancomycin and linezolid resistant isolates and isolates with decreased daptomycin susceptibility. Moreover, new clones (ST398) have emerged, initially associated with piggeries, and new mec variants (mecC) with livestock origin that escape to the detection with current molecular methods based on mecA gene have been detected. In enterococci, linzeolid resistant isolates and isolates with deceased susceptibility to daptomycin have been described. Moreover, ampicillin resistant Enterococcus faecium due to β-lactamase production has been recently found in Europe. Control of MRSA isolates and multiresistant enteroccocci should combined antibiotic stewardship strategies and epidemiological measures, including detection of colonized patients in order to reduce colonization pressure and their transmission.

  20. Enterococcus faecalis as multidrug resistance strains in clinical isolates in Imam Reza Hospital in Kermanshah, Iran.

    PubMed

    Mohammadi, F; Ghafourian, S; Mohebi, R; Taherikalani, M; Pakzad, I; Valadbeigi, H; Hatami, V; Sadeghifard, N

    2015-01-01

    The current study aimed to investigate the prevalence of vancomycin-resistant Enterococcus in E. faecalis and E. faecium and antimicrobial susceptibility patterns, then dominant genes responsible for vancomycin resistance were determined. For this propose, 180 clinical isolates of Enterococcus were subjected for identification and antibiotic susceptibility assay. Then, the gene responsible vancomycin resistant strains were determined. The results demonstrated the E. faecalis as a dominant Enterococcus. Resistance to erythromycin was dominant and multidrug resistance strains observed in E. faecalis. vanA was responsible for vancomycin resistance. In conclusion, a high rate of resistance to antibiotics in Enterococcus is clearly problematic, and a novel strategy is needed to decrease resistance in Enterococcus.

  1. Cloning

    MedlinePlus

    Cloning describes the processes used to create an exact genetic replica of another cell, tissue or organism. ... named Dolly. There are three different types of cloning: Gene cloning, which creates copies of genes or ...

  2. A New High-Level Gentamicin Resistance Gene, aph(2")-Id, in Enterococcus spp.

    PubMed Central

    Tsai, Shane F.; Zervos, Marcus J.; Clewell, Don B.; Donabedian, Susan M.; Sahm, Daniel F.; Chow, Joseph W.

    1998-01-01

    Enterococcus casseliflavus UC73 is a clinical blood isolate with high-level resistance to gentamicin. DNA preparations from UC73 failed to hybridize with intragenic probes for aac(6′)-Ie-aph(2")-Ia and aph(2")-Ic. A 4-kb fragment from UC73 was cloned and found to confer resistance to gentamicin in Escherichia coli DH5α transformants. Nucleotide sequence analysis revealed the presence of a 906-bp open reading frame whose deduced amino acid sequence had a region with homology to the aminoglycoside-modifying enzyme APH(2")-Ic and to the C-terminal domain of the bifunctional enzyme AAC(6′)-APH(2"). The gene is designated aph(2")-Id, and its observed phosphotransferase activity is designated APH(2")-Id. A PCR-generated intragenic probe hybridized to the genomic DNA from 17 of 118 enterococcal clinical isolates (108 with high-level gentamicin resistance) from five hospitals. All 17 were vancomycin-resistant Enterococcus faecium isolates, and pulsed-field typing revealed three distinct clones. The combination of ampicillin plus either amikacin or neomycin exhibited synergistic killing against E. casseliflavus UC73. Screening and interpretation of high-level aminoglycoside resistance in enterococci may need to be modified to include detection of APH(2")-Id. PMID:9593155

  3. The Crystal Structures of Substrate and Nucleotide Complexes of Enterococcus faecium Aminoglycoside-2′′-Phosphotransferase-IIa [APH(2′′)-IIa] Provide Insights into Substrate Selectivity in the APH(2′′) Subfamily▿ ‡

    PubMed Central

    Young, Paul G.; Walanj, Rupa; Lakshmi, Vendula; Byrnes, Laura J.; Metcalf, Peter; Baker, Edward N.; Vakulenko, Sergei B.; Smith, Clyde A.

    2009-01-01

    Aminoglycoside-2′′-phosphotransferase-IIa [APH(2′′)-IIa] is one of a number of homologous bacterial enzymes responsible for the deactivation of the aminoglycoside family of antibiotics and is thus a major component in bacterial resistance to these compounds. APH(2′′)-IIa produces resistance to several clinically important aminoglycosides (including kanamycin and gentamicin) in both gram-positive and gram-negative bacteria, most notably in Enterococcus species. We have determined the structures of two complexes of APH(2′′)-IIa, the binary gentamicin complex and a ternary complex containing adenosine-5′-(β,γ-methylene)triphosphate (AMPPCP) and streptomycin. This is the first crystal structure of a member of the APH(2′′) family of aminoglycoside phosphotransferases. The structure of the gentamicin-APH(2′′)-IIa complex was solved by multiwavelength anomalous diffraction methods from a single selenomethionine-substituted crystal and was refined to a crystallographic R factor of 0.210 (Rfree, 0.271) at a resolution of 2.5 Å. The structure of the AMPPCP-streptomycin complex was solved by molecular replacement using the gentamicin-APH(2′′)-IIa complex as the starting model. The enzyme has a two-domain structure with the substrate binding site located in a cleft in the C-terminal domain. Gentamicin binding is facilitated by a number of conserved acidic residues lining the binding cleft, with the A and B rings of the substrate forming the majority of the interactions. The inhibitor streptomycin, although binding in the same pocket as gentamicin, is orientated such that no potential phosphorylation sites are adjacent to the catalytic aspartate residue. The binding of gentamicin and streptomycin provides structural insights into the substrate selectivity of the APH(2′′) subfamily of aminoglycoside phosphotransferases, specifically, the selectivity between the 4,6-disubstituted and the 4,5-disubstituted aminoglycosides. PMID:19429619

  4. Experimental study of the impact of antimicrobial treatments on Campylobacter, Enterococcus and PCR-capillary electrophoresis single-strand conformation polymorphism profiles of the gut microbiota of chickens.

    PubMed

    Mourand, Gwenaëlle; Jouy, Eric; Bougeard, Stéphanie; Dheilly, Alexandra; Kérouanton, Annaëlle; Zeitouni, Salman; Kempf, Isabelle

    2014-11-01

    An experiment was conducted to compare the impact of antimicrobial treatments on the susceptibility of Campylobacter, Enterococcus faecium and Enterococcus faecalis, and on the diversity of broiler microbiota. Specific-pathogen-free chickens were first orally inoculated with strains of Campylobacter and Enterococcus faecium. Birds were then orally treated with recommended doses of oxytetracycline, sulfadimethoxine/trimethoprim, amoxicillin or enrofloxacin. Faecal samples were collected before, during and after antimicrobial treatment. The susceptibility of Campylobacter, Enterococcus faecium and Enterococcus faecalis strains isolated on supplemented or non-supplemented media was studied and PCR-capillary electrophoresis single-strand conformation polymorphism (CE-SSCP) profiles of the gut microbiota were analysed. Enrofloxacin-resistant Campylobacter were selected in the enrofloxacin-treated group and showed the Thr86Ile mutation in the gyrA gene. Acquisition of the tetO gene in Campylobacter coli isolates was significantly more frequent in birds given oxytetracycline. No impact of amoxicillin treatment on the susceptibility of Campylobacter could be detected. Ampicillin- and sulfadimethoxine/trimethoprim-resistant Enterococcus faecium were selected in amoxicillin-treated broilers, but no selection of the inoculated vancomycin-resistant Enterococcus faecium could be detected, although it was also resistant to tetracycline and sulfadimethoxine/trimethoprim. PCR-CE-SSCP revealed significant variations in a few peaks in treated birds as compared with non-treated chickens. In conclusion, antimicrobial treatments perturbed chicken gut microbiota, and certain antimicrobial treatments selected or co-selected resistant strains of Campylobacter and Enterococcus.

  5. Enterococcus Xinjiangensis sp. nov., Isolated from Yogurt of Xinjiang, China.

    PubMed

    Ren, Xiaopu; Li, Mingyang; Guo, Dongqi

    2016-09-01

    A Gram-strain-positive bacterial strain 48(T) was isolated from traditional yogurt in Xinjiang Province, China. The bacterium was characterized by a polyphasic approach, including 16S rRNA gene sequence analysis, polymerase α subunit (rpoA) gene sequence analysis, determination of DNA G+C content, DNA-DNA hybridization with the type strain of Enterococcus ratti and analysis of phenotypic features. Strain 48(T) accounted for 96.1, 95.8, 95.8, and 95.7 % with Enterococcus faecium CGMCC 1.2136(T), Enterococcus hirae ATCC 9790(T), Enterococcus durans CECT 411(T), and E. ratti ATCC 700914(T) in the 16S rRNA gene sequence similarities, respectively. The sequence of rpoA gene showed similarities of 99.0, 96.0, 96.0, and 96 % with that of E. faecium ATCC 19434(T), Enterococcus villorum LMG12287, E. hirae ATCC 9790(T), and E. durans ATCC 19432(T), respectively. Based upon of polyphasic characterization data obtained in the study, a novel species, Enterococcus xinjiangensis sp. nov., was proposed and the type strain was 48(T)(=CCTCC AB 2014041(T) = JCM 30200(T)).

  6. Enterococcus lactis sp. nov., from Italian raw milk cheeses.

    PubMed

    Morandi, Stefano; Cremonesi, Paola; Povolo, Milena; Brasca, Milena

    2012-08-01

    Ten atypical Enterococcus strains were isolated from Italian raw milk cheeses. The 16S rRNA gene, phenylalanyl-tRNA synthase alpha subunit (pheS), RNA polymerase alpha subunit (rpoA) and the 16S-23S rRNA intergenic transcribed spacer (ITS) sequences, randomly amplified polymorphic DNA (RAPD) PCR and the phenotypic properties revealed that the isolates represent a novel enterococcal species. On the basis of 16S rRNA gene sequence analysis, the isolates were closely related to Enterococcus hirae ATCC 8043(T), Enterococcus durans CECT 411(T) and Enterococcus faecium ATCC 19434(T), with 98.8, 98.9 and 99.4% sequence similarity, respectively. On the basis of sequence analysis of the housekeeping gene pheS, the reference strain, BT159(T), occupied a position separate from E. faecium LMG 16198. The group of isolates could be easily differentiated from recognized species of the genus Enterococcus by 16S-23S rRNA ITS analysis, RAPD-PCR and phenotypic characteristics. The name Enterococcus lactis sp. nov. is proposed, with BT159(T) ( = DSM 23655(T) = LMG 25958(T)) as the type strain.

  7. Australian Group on Antimicrobial Resistance Enterococcus Surveillance Programme annual report, 2010.

    PubMed

    Coombs, Geoffrey W; Pearson, Julie C; Christiansen, Keryn; Gottlieb, Thomas; Bell, Jan M; George, Narelle; Turnidge, John D

    2013-09-30

    In 2010, 15 institutions around Australia conducted a period prevalence study of key resistances in isolates of Enterococcus species associated with a range of clinical disease amongst in- and outpatients. Each institution collected up to 100 consecutive isolates and tested these for susceptibility to commonly used antimicrobials using standardised methods. Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis were characterised by pulsed-field gel electrophoresis. Multilocus sequence typing was performed on representative pulsotypes of E. faecium. Susceptibility results were compared with similar surveys conducted in 1995, 1999, 2003, 2005, 2007 and 2009. In the 2010 survey, E. faecalis (1,201 isolates) and E. faecium (170 isolates) made up 98.9% of the 1,386 isolates tested. Ampicillin resistance was very common (85.3%) in E. faecium and absent in E. faecalis. Non-susceptibility to vancomycin was 36.5% in E. faecium (similar to the 35.2% in 2009 but up from 15.4% in the 2007 survey) and 0.5% in E. faecalis. There were significant differences in the proportion of vancomycin-resistant E. faecium between the states ranging from 0% in Western Australia to 54.4% in South Australia. The vanB gene was detected in 62 E. faecium and 3 E. faecalis isolates. The vanA gene was detected in 1 E. faecium isolate. All vancomycin-resistant E. faecium belonged to clonal complex 17. The most common sequence type (ST) was ST203, which was found in all regions that had reports of vancomycin resistant enterococci. ST341 was detected only in New South Wales/Australian Capital Territory and ST414 only in South Australia and Victoria. High-level resistance to gentamicin was 34.1% in E. faecalis and 66.1% in E. faecium. A subset of isolates was tested against high-level streptomycin, linezolid and quinupristin/dalfopristin. High-level streptomycin resistance was found in 8.2% of E. faecalis isolates and 43.8% of E. faecium isolates. Linezolid non

  8. Cloning

    MedlinePlus

    ... that have been cloned from somatic cells include: cat, deer, dog, horse, mule, ox, rabbit and rat. ... with cell division. In other mammals, such as cats, rabbits and mice, the two spindle proteins are ...

  9. Diverse antimicrobial activity from Enterococcus faecium NRRL B-30746 bacteriocin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic therapy to resolve bacterial disease has been compromised by the increased prevalence and magnitude of bacterial antibiotic resistance. In our efforts to identify new effective antimicrobials, bacteria isolated from poultry intestinal contents were screened for bacteriocin synthesis again...

  10. Eight-year Surveillance of Antimicrobial Resistance among Enterococcus Spp. Isolated in the First Bethune Hospital

    NASA Astrophysics Data System (ADS)

    Xu, Jiancheng; Wang, Liqiang; Wang, Kai; Zhou, Qi

    This study was to investigate the antimicrobial resistance of Enterococcus spp. isolated in 8 consecutive years in the First Bethune Hospital. Disk diffusion test was used to study the antimicrobial resistance. The data were analyzed by WHONET 5 software according to Clinical and Laboratory Standards Institute (CLSI). Most of 1446 strains of Enterococcus spp. were collected from urine 640 (44.3%), sputum 315 (21.8%), secretions and pus 265 (18.3%) during the past 8 years. The rates of high-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium were 57.4%∼75.9% and 69.0%∼93.8% during the past 8 years, respectively. No Enterococcus spp. was resistant to vancomycin. The antimicrobial resistance of Enterococcus spp. had increased in recent 8 years. The change of the antimicrobial resistance should be investigated in order to direct rational drug usage in the clinic and prevent bacterial strain of drug resistance from being transmitted.

  11. Enterococcus spp. in a single blood culture: bacteremia or contamination?

    PubMed

    Khatib, R; Labalo, V; Sharma, M; Johnson, L B; Riederer, K

    2017-03-01

    We retrospectively evaluated adult cases with Enterococcus spp. in 1 blood culture (BC) (1/1/2010-12/31/2015; n=294) and stratified them into bacteremia or contamination. Contamination frequency was similar in community versus hospital-onset, E. faecalis versus E. faecium, and number of BC drawn per day. Contamination predictors were vancomycin-resistance, ampicillin-resistance, commensal organism copresence, and nonurinary/abdominal sources.

  12. Characterization of vancomycin-resistant Enterococcus isolates from broilers in Selangor, Malaysia.

    PubMed

    Getachew, Y M; Hassan, L; Zakaria, Z; Saleha, A A; Kamaruddin, M I; Che Zalina, M Z

    2009-12-01

    Vancomycin-resistant Enterococcus (VRE) is an emerging nosocomial pathogen in humans. The use of antibiotics in human therapy and in the production of food animals has been incriminated in the emergence of this organism. The present study describes the distribution of VRE species, the vancomycin-resistant genes detected, the vancomycin resistance pattern observed, and the genetic diversity of the isolates found in live broiler chickens in Malaysia. Overall 140 VRE were isolated with species comprising Enterococcus faecalis (48%), Enterococcus faecium (25.7%), Enterococcus gallinarum (12.1%), Enterococcus casseliflavus (1.4%) and other Enterococcus species (12.8%). Vancomycin resistance gene vanA and intrinsic genes vanC1 and vanC2/3 were detected in the study population. VanA was detected in 15 (63.9%) of E. faecium, 23 (22.4%) of E. faecalis and in 3 (17.6%) E. gallinarum isolates. E-test was conducted on randomly selected 41 of the isolates and the minimum inhibition concentration (MIC) of vancomycin for five (11.9%) of tested isolates is more than 256 μg/ml. Genotypic analysis using random amplified polymorphic DNA (RAPD) showed genetic diversity within the Enterococcus species.

  13. Population biology of intestinal enterococcus isolates from hospitalized and nonhospitalized individuals in different age groups.

    PubMed

    Tedim, Ana P; Ruiz-Garbajosa, Patricia; Corander, Jukka; Rodríguez, Concepción M; Cantón, Rafael; Willems, Rob J; Baquero, Fernando; Coque, Teresa M

    2015-03-01

    The diversity of enterococcal populations from fecal samples from hospitalized (n = 133) and nonhospitalized individuals (n = 173) of different age groups (group I, ages 0 to 19 years; group II, ages 20 to 59 years; group III, ages ≥60 years) was analyzed. Enterococci were recovered at similar rates from hospitalized and nonhospitalized persons (77.44% to 79.77%) of all age groups (75.0% to 82.61%). Enterococcus faecalis and Enterococcus faecium were predominant, although seven other Enterococcus species were identified. E. faecalis and E. faecium (including ampicillin-resistant E. faecium) colonization rates in nonhospitalized persons were age independent. For inpatients, E. faecalis colonization rates were age independent, but E. faecium colonization rates (particularly the rates of ampicillin-resistant E. faecium colonization) significantly increased with age. The population structure of E. faecium and E. faecalis was determined by superimposing goeBURST and Bayesian analysis of the population structure (BAPS). Most E. faecium sequence types (STs; 150 isolates belonging to 75 STs) were linked to BAPS groups 1 (22.0%), 2 (31.3%), and 3 (36.7%). A positive association between hospital isolates and BAPS subgroups 2.1a and 3.3a (which included major ampicillin-resistant E. faecium human lineages) and between community-based ampicillin-resistant E. faecium isolates and BAPS subgroups 1.2 and 3.3b was found. Most E. faecalis isolates (130 isolates belonging to 58 STs) were grouped into 3 BAPS groups, BAPS groups 1 (36.9%), 2 (40.0%), and 3 (23.1%), with each one comprising widespread lineages. No positive associations with age or hospitalization were established. The diversity and dynamics of enterococcal populations in the fecal microbiota of healthy humans are largely unexplored, with the available knowledge being fragmented and contradictory. The study offers a novel and comprehensive analysis of enterococcal population landscapes and suggests that E. faecium

  14. Population Biology of Intestinal Enterococcus Isolates from Hospitalized and Nonhospitalized Individuals in Different Age Groups

    PubMed Central

    Tedim, Ana P.; Ruiz-Garbajosa, Patricia; Corander, Jukka; Rodríguez, Concepción M.; Cantón, Rafael; Willems, Rob J.; Baquero, Fernando

    2014-01-01

    The diversity of enterococcal populations from fecal samples from hospitalized (n = 133) and nonhospitalized individuals (n = 173) of different age groups (group I, ages 0 to 19 years; group II, ages 20 to 59 years; group III, ages ≥60 years) was analyzed. Enterococci were recovered at similar rates from hospitalized and nonhospitalized persons (77.44% to 79.77%) of all age groups (75.0% to 82.61%). Enterococcus faecalis and Enterococcus faecium were predominant, although seven other Enterococcus species were identified. E. faecalis and E. faecium (including ampicillin-resistant E. faecium) colonization rates in nonhospitalized persons were age independent. For inpatients, E. faecalis colonization rates were age independent, but E. faecium colonization rates (particularly the rates of ampicillin-resistant E. faecium colonization) significantly increased with age. The population structure of E. faecium and E. faecalis was determined by superimposing goeBURST and Bayesian analysis of the population structure (BAPS). Most E. faecium sequence types (STs; 150 isolates belonging to 75 STs) were linked to BAPS groups 1 (22.0%), 2 (31.3%), and 3 (36.7%). A positive association between hospital isolates and BAPS subgroups 2.1a and 3.3a (which included major ampicillin-resistant E. faecium human lineages) and between community-based ampicillin-resistant E. faecium isolates and BAPS subgroups 1.2 and 3.3b was found. Most E. faecalis isolates (130 isolates belonging to 58 STs) were grouped into 3 BAPS groups, BAPS groups 1 (36.9%), 2 (40.0%), and 3 (23.1%), with each one comprising widespread lineages. No positive associations with age or hospitalization were established. The diversity and dynamics of enterococcal populations in the fecal microbiota of healthy humans are largely unexplored, with the available knowledge being fragmented and contradictory. The study offers a novel and comprehensive analysis of enterococcal population landscapes and suggests that E. faecium

  15. AN EFFICIENT IMMUNOMAGNETIC CAPTURE SYSTEM FOR ENTEROCOCCUS FAECALIS AND ENTEROCOCCUS FAECIUM

    EPA Science Inventory

    Enterococci detection is one of the two approved procedures by the US Environmental Protection Agency (EPA) used for the assessment of the microbiological quality of recreational waters. The action levels established by the EPA for enterococci are 35 pr 100 ml in marine recreati...

  16. Multiple antibiotic resistances of Enterococcus isolates from raw or sand-filtered sewage.

    PubMed

    Xu, Junyi; Gallert, Claudia; Winter, Josef

    2007-02-01

    Fifty antibiotic-resistant Enterococcus strains were isolated from raw sewage of a wastewater treatment plant and from the same sewage after trickling through a 25-cm sand column, which retained >99% of the initial population. All 50 Enterococcus isolates were resistant against triple sulfa and trimethoprim/sulfamethoxazole and none were resistant against vancomycin. Most of the isolates from raw sewage were resistant to more antibiotics than the isolates from sand column effluent. One Enterococcus isolate from raw sewage (no. 61) and one Enterococcus isolate from sand column effluent (no. 95) had ten antibiotic resistances each. Isolate no. 95 maintained its resistances in the absence of antibiotics during the whole study. It was compared with isolate no. 70, which was one of the isolates, being resistant only against the two sulfonamides. Phenotypically and biochemically, the two organisms were strains of Enterococcus faecalis. Sequence analysis of partical 16S rDNA allowed alignment of isolate no. 95 as a strain of Enterococcus faecium and of isolate no. 70 as a strain of E. faecalis. E. faecium strain no. 95 carried at least six different plasmids, whereas for E. faecalis strain no. 70, no discrete plasmid band was seen on the gels.

  17. Use of Enterococcus, BST and sterols as indicators for poultry pollution source tracking in surface and groundwater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study has applied Enterococcus, Bacterial Source Tracking (BST) and sterol analysis for pollution source identification from poultry sources. Fecal contamination was detected in 100% of surface water and 15% of groundwater sites tested. E. faecium was the dominant species in aged litter sampl...

  18. Enterococcus species composition determined by capillary electrophoresis of the groESL gene spacer region DNA.

    PubMed

    Yasuda, M; Paar, J; Doolittle, M; Brochi, J; Pancorbo, O C; Tang, R J; Stoner, R E; Shiaris, M P

    2010-07-01

    Marine recreational beaches are monitored for fecal contamination by Enterococcus spp. (ENT) counts. Although different ENT species in the environment tend to thrive in and originate from distinct hosts, the current monitoring method does not differentiate among species. Time-consuming isolation-based species identification precludes routine analysis of environmental ENT communities. Therefore, an isolation-independent DNA fingerprinting method was developed to characterize environmental ENT communities using DNA length polymorphism of the spacer region between the groES and groEL genes common to most ENT species. Capillary electrophoresis resulted in distinct peak sizes of PCR products that carried polymorphic groESL spacers (300-335 bp in length) among 8 different ENT species (Enterococcus avium, Enterococcus gallinarum, Enterococcus casseliflavus, Enterococcus mundtii, Enterococcus hirae, Enterococcus faecium, Enterococcus durans, and Enterococcus faecalis). Distortions in true species ratios observed in electropherograms were caused by PCR biases arising in a mixed ENT community DNA template. E. faecalis was overestimated and E. avium and E. faecium were underestimated compared to the original species ratios in the mixed community. The PCR product bias was constant between species, so good approximation of the species ratio in ENT communities is possible. In environmental samples, a high percentage of E. faecalis (96%) together with high total ENT counts were observed in samples collected from a sewer line and from several sites in a storm drain system where sewage leaks were suspected. In contrast, samples with <400 CFU 100 ml-1 ENT were either dominated by E. mundtii or had 4 or more ENT species. The latter ENT community profiles are considered to be signatures of enterococci rarely associated with animals with low or of non-fecal origin.

  19. Insertion sequence-driven diversification creates a globally dispersed emerging multiresistant subspecies of E. faecium.

    PubMed

    Leavis, Helen L; Willems, Rob J L; van Wamel, Willem J B; Schuren, Frank H; Caspers, Martien P M; Bonten, Marc J M

    2007-01-01

    Enterococcus faecium, an ubiquous colonizer of humans and animals, has evolved in the last 15 years from an avirulent commensal to the third most frequently isolated nosocomial pathogen among intensive care unit patients in the United States. E. faecium combines multidrug resistance with the potential of horizontal resistance gene transfer to even more pathogenic bacteria. Little is known about the evolution and virulence of E. faecium, and genomic studies are hampered by the absence of a completely annotated genome sequence. To further unravel its evolution, we used a mixed whole-genome microarray and hybridized 97 E. faecium isolates from different backgrounds (hospital outbreaks (n = 18), documented infections (n = 34) and asymptomatic carriage of hospitalized patients (n = 15), and healthy persons (n = 15) and animals (n = 21)). Supported by Bayesian posterior probabilities (PP = 1.0), a specific clade containing all outbreak-associated strains and 63% of clinical isolates was identified. Sequencing of 146 of 437 clade-specific inserts revealed mobile elements (n = 74), including insertion sequence (IS) elements (n = 42), phage genes (n = 6) and plasmid sequences (n = 26), hypothetical (n = 58) and membrane proteins (n = 10), and antibiotic resistance (n = 9) and regulatory genes (n = 11), mainly located on two contigs of the unfinished E. faecium DO genome. Split decomposition analysis, varying guanine cytosine content, and aberrant codon adaptation indices all supported acquisition of these genes through horizontal gene transfer with IS16 as the predicted most prominent insert (98% sensitive, 100% specific). These findings suggest that acquisition of IS elements has facilitated niche adaptation of a distinct E. faecium subpopulation by increasing its genome plasticity. Increased genome plasticity was supported by higher diversity indices (ratio of average genetic similarities of pulsed-field gel electrophoresis and multi locus sequence typing) for clade

  20. [Influence of staphylococcin T on Enterococcus sp. growth].

    PubMed

    Białucha, Agata; Kozuszko, Sylwia; Gospodarek, Eugenia; Bugalski, Roman Marian; Gierlotka, Krzysztof

    2007-01-01

    Bacteriocins are ribosomally synthesised, extracellular bacterial products. Generally, spectrum of inhibition is limited to the same or closely related species to bacteriocin producer. Staphylococcin T is produced by Staphylococcus cohnii strain. The present study concerns influence of StT to 267 Enterococcus sp. strains growth isolated between 2003 and 2006 in Department of Microbiology University Hospital of dr. A. Jurasz in Bydgoszcz. S. cohnii T antagonistic ability evaluated towards bacteries on Mueller-Hinton Agar (bio Mérieux) in aerobic conditions. After 24 and 48 hours tested enterococci suspensions were plated perpendiculary. Susceptibility to antibiotics was assessed by disc diffusion method according to the guideless of Clinical and Laboratory Standards Institute and National Reference Centre for Antimicrobial Susceptibility. Among Enterococcus sp. strains tested 7.1% were sensitive to StT. The highest percentage of sensitive enterococci isolated from wound swabs, urine, blood and pus. Enterococcus faecium strains dominated (63.2%) among enterococci sensitive to StT. Moderate inhibition degree on S. cohnii T bacteriocin action was observed in majority sensitive enterococci strains. Enterococcus sp. sensitive to StT strains were frequently multidrug resistant (68.4%). According to the study results and increasing resistance to antibiotics, StT could be an alternative agent used to treat infections caused by Enterococcus sp.

  1. Drug resistance & virulence determinants in clinical isolatesof Enterococcus species

    PubMed Central

    Fernandes, Sanal C.; Dhanashree, B.

    2013-01-01

    Background & objectives: Enterococci are the leading cause of nosocomial infections, and are thus a persisting clinical problem globally. We undertook this study to determine the virulence factors and the antibiotic resistance in Enterococcus clinical isolates. Methods: One hundred and fifty Enterococcus isolates obtained from various clinical specimens were speciated biochemically and subjected to antibiotic susceptibility testing using Kirby-Bauer disk diffusion method. Resistance to vancomycin was determined by using agar screen method. Haemolysin and gelatinase productions were detected using 5 per cent sheep blood agar and 12 per cent gelatin agar, respectively. Results: Among the 150 Enterococcus isolates, 84 (56%) were E. faecalis. 51(34%) E. faecium, and 15 (10%) were other Enterococcus spp. Haemolysin production was seen among 123 (82%) isolates while 61 (40.6%) isolates produced gelatinase. Nearly 50 per cent of the isolates showed high level aminoglycoside resistance (HLAR). A total of 13 (8.6%) isolates showed vancomycin resistance, of which 11(7.3%) had an MIC >8 μg/ml. Interpretation & conclusions: Presence of VRE was found to be low among the isolates studied. However, occurrence of VRE along with HLAR calls for regular detection of vancomycin resistance promptly and accurately to recognize VRE colonization and infection. Early detection of VRE and HLAR along with their virulence trait will help in preventing the establishment and spread of multidrug resistant Enterococcus species. PMID:23760387

  2. [Comparison of Phoenix Automated System, API ID 32 Strep System and LightCycler Enterococcus MGRADE System in the Identification of Clinical Enterococcus Isolates].

    PubMed

    Cekin, Yeşim; Ozhak Baysan, Betil; Mutlu, Derya; Sepin Özen, Nevgün; Ongüt, Gözde; Dönmez, Levent; Oğünç, Dilara; Colak, Dilek

    2013-01-01

    Enterococci which are part of the commensal flora of the human gastrointestinal and genitourinary tracts, are increasing in importance as the cause of hospital-acquired infections. Identification of Enterococcus spp. at the species level is of great importance, for appropriate treatment of patients, infection control and to supply epidemiological data. Conventional methods for the identification of enterococcus isolates at species level is difficult and time consuming. Correct identification of enterococcus isolates in clinical microbiology laboratory by conventional methods is replaced by semi-automated or automated identification and molecular methods. The aim of this study was to evaluate the performance of Phoenix automated system (BD Diagnostic Systems, USA), API Rapid ID 32 Strep System (bioMerieux, France) and Enterococcus MGRADE LightCycler kit (Roche Molecular Biochemicals, Germany) used in real-time polymerase chain reaction (Rt-PCR), for the species level identification of enterococcus strains isolated from clinical specimens. A total of 90 vancomycin susceptible enterococci isolated from different patients were identified by all of the three commercial systems, together with conventional methods. Of the strains, 59 were identified as E.faecalis, 28 were E.faecium, and one of each as E.raffinosus, E.hirae and E.casseliflavus with conventional methods. One E.faecalis strain identified by the conventional system was identified as E.faecium by Phoenix system and one E.faecium strain as E.durans. One E.raffinosus strain identifed by the conventional method was identified as E.avium by API. Conventionally identified four E.faecalis strains were determined to be E.faecium by Rt-PCR and one E.faecium, one E.raffinosus and one E.casseliflavus as E.faecalis. Accordingly, the consistency of Phoenix, API Rapid ID 32 Strep and LightCycler Enterococcus MGRADE systems with the conventional methods were detected as 97.8% (88/90), 98.9% (89/90), and 92.2% (83

  3. Prevalence of enterococcus species and their virulence genes in fresh water prior to and after storm events.

    PubMed

    Sidhu, J P S; Skelly, E; Hodgers, L; Ahmed, W; Li, Y; Toze, S

    2014-01-01

    Enterococcus spp. isolates (n = 286) collected from six surface water bodies in subtropical Brisbane, Australia, prior to and after storm events, were identified to species level and tested for the presence of seven clinically important virulence genes (VGs). Enterococcus faecalis (48%), Enterococcus faecium (14%), Enterococcus mundtii (13%), and Enterococcus casseliflavus (13%) were frequently detected at all sites. The frequency of E. faecium occurrence increased from 6% in the dry period to 18% after the wet period. The endocarditis antigen (efaA), gelatinase (gelE), collagen-binding protein (ace), and aggregation substance (asa1) were detected in 61%, 43%, 43%, and 23% of Enterococcus isolates, respectively. The chances of occurrence of ace, gelE, efaA, and asa1 genes in E. faecalis were found to be much higher compared to the other Enterococcus spp. The observed odds ratio of occurrence of ace and gelE genes in E. faecalis was much higher at 7.96 and 6.40 times, respectively. The hyl gene was 3.84 times more likely to be detected in E. casseliflavus. The presence of multiple VGs in most of the E. faecalis isolates underscores the importance of E. faecalis as a reservoir of VGs in the fresh water aquatic environment. Consequently, if contaminated surface water is to be used for production of potable and nonpotable water some degree of treatment depending upon intended use such as detention in basins prior to use or chlorination is required.

  4. Targeting Enterococcus faecalis Biofilms with Phage Therapy

    PubMed Central

    Khalifa, Leron; Brosh, Yair; Gelman, Daniel; Coppenhagen-Glazer, Shunit; Beyth, Shaul; Poradosu-Cohen, Ronit; Que, Yok-Ai; Beyth, Nurit

    2015-01-01

    Phage therapy has been proven to be more effective, in some cases, than conventional antibiotics, especially regarding multidrug-resistant biofilm infections. The objective here was to isolate an anti-Enterococcus faecalis bacteriophage and to evaluate its efficacy against planktonic and biofilm cultures. E. faecalis is an important pathogen found in many infections, including endocarditis and persistent infections associated with root canal treatment failure. The difficulty in E. faecalis treatment has been attributed to the lack of anti-infective strategies to eradicate its biofilm and to the frequent emergence of multidrug-resistant strains. To this end, an anti-E. faecalis and E. faecium phage, termed EFDG1, was isolated from sewage effluents. The phage was visualized by electron microscopy. EFDG1 coding sequences and phylogeny were determined by whole genome sequencing (GenBank accession number KP339049), revealing it belongs to the Spounavirinae subfamily of the Myoviridae phages, which includes promising candidates for therapy against Gram-positive pathogens. This analysis also showed that the EFDG1 genome does not contain apparent harmful genes. EFDG1 antibacterial efficacy was evaluated in vitro against planktonic and biofilm cultures, showing effective lytic activity against various E. faecalis and E. faecium isolates, regardless of their antibiotic resistance profile. In addition, EFDG1 efficiently prevented ex vivo E. faecalis root canal infection. These findings suggest that phage therapy using EFDG1 might be efficacious to prevent E. faecalis infection after root canal treatment. PMID:25662974

  5. Targeting Enterococcus faecalis biofilms with phage therapy.

    PubMed

    Khalifa, Leron; Brosh, Yair; Gelman, Daniel; Coppenhagen-Glazer, Shunit; Beyth, Shaul; Poradosu-Cohen, Ronit; Que, Yok-Ai; Beyth, Nurit; Hazan, Ronen

    2015-04-01

    Phage therapy has been proven to be more effective, in some cases, than conventional antibiotics, especially regarding multidrug-resistant biofilm infections. The objective here was to isolate an anti-Enterococcus faecalis bacteriophage and to evaluate its efficacy against planktonic and biofilm cultures. E. faecalis is an important pathogen found in many infections, including endocarditis and persistent infections associated with root canal treatment failure. The difficulty in E. faecalis treatment has been attributed to the lack of anti-infective strategies to eradicate its biofilm and to the frequent emergence of multidrug-resistant strains. To this end, an anti-E. faecalis and E. faecium phage, termed EFDG1, was isolated from sewage effluents. The phage was visualized by electron microscopy. EFDG1 coding sequences and phylogeny were determined by whole genome sequencing (GenBank accession number KP339049), revealing it belongs to the Spounavirinae subfamily of the Myoviridae phages, which includes promising candidates for therapy against Gram-positive pathogens. This analysis also showed that the EFDG1 genome does not contain apparent harmful genes. EFDG1 antibacterial efficacy was evaluated in vitro against planktonic and biofilm cultures, showing effective lytic activity against various E. faecalis and E. faecium isolates, regardless of their antibiotic resistance profile. In addition, EFDG1 efficiently prevented ex vivo E. faecalis root canal infection. These findings suggest that phage therapy using EFDG1 might be efficacious to prevent E. faecalis infection after root canal treatment.

  6. Development of a Rapid Identification Method for the Differentiation of Enterococcus Species Using a Species-Specific Multiplex PCR Based on Comparative Genomics.

    PubMed

    Park, Jongbin; Jin, Gwi-Deuk; Pak, Jae In; Won, Jihyun; Kim, Eun Bae

    2017-04-01

    Enterococci are lactic acid bacteria that are commonly found in food and in animal gut. Since 16 S ribosomal RNA (rRNA) sequences, genetic markers for bacterial identification, are similar among several Enterococcus species, it is very difficult to determine the correct species based on only 16 S rRNA sequences. Therefore, we developed a rapid method for the identification of different Enterococcus species using comparative genomics. We compared 38 genomes of 13 Enterococcus species retrieved from the National Center of Biotechnology Information database and identified 25,623 orthologs. Among the orthologs, four genes were specific to four Enterococcus species (Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, and Enterococcus durans). We designed species-specific primer sets targeting the genes and developed a multiplex PCR using primer sets that could distinguish the four Enterococcus species among the nine strains of Enterococcus species that were available locally. The multiplex PCR method also distinguished the four species isolated from various environments, such as feces of chicken and cow, meat of chicken, cow, and pigs, and fermented soybeans (Cheonggukjang and Doenjang). These results indicated that our novel multiplex PCR using species-specific primers could identify the four Enterococcus species in a rapid and easy way. This method will be useful to distinguish Enterococcus species in food, feed, and clinical settings.

  7. [Comparison of microdilution method and Phoenix automated system for testing antimicrobial susceptibilities of Enterococcus strains].

    PubMed

    Gülmez, Dolunay; Hasçelik, Gülşen

    2011-01-01

    Enterococcus spp. are important pathogens which are intrinsically resistant to most of the commonly used antimicrobial agents such as aminoglycosides and cephalosporins. Accurate determination of resistance is important to ensure appropriate antimicrobial therapy. This study was undertaken to compare the susceptibility results obtained by Phoenix system (Becton Dickinson, USA) with reference microdilution method. We included 1248 Enterococcus spp. (903 Enterococcus faecalis, 345 Enterococcus faecium) strains isolated from clinical samples between 2005-2007 in routine microbiology laboratory of Hacettepe University Hospital. The strains were identified and the antimicrobial susceptibilities were determined by the Phoenix system. Antimicrobial susceptibilities to ampicillin, teicoplanin, vancomycin, gentamicin and streptomycin were also studied by microdilution method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Evaluation revealed excellent agreement for all of the antibiotics with category agreement rates of > 97%. Among 1248 strains, 76 revealed discordant results. Very major error rates were 1.5% for ampicillin, 1.3% for gentamicin, and 0.9% for streptomycin. Major error rates were 1.4% for streptomycin, 0.6% for ampicillin and vancomycin and 0.3% for gentamicin. Minor error rates were found as 0.2% for vancomycin, and 0.1% for teicoplanin. Resistance rates obtained by microdilution were as follows; high level streptomycin 44%, high level gentamicin 29.7%, ampicillin 25.6%, vancomycin 2.2% and teicoplanin 2.2%. Resistance rates were higher in E.faecium than E.faecalis and 96.4% of the vancomycin resistant enterococcus isolates were identified as E.faecium. In conclusion, based on the data obtained, Phoenix system is reliable for testing susceptibilities of Enterococcus spp. to these antimicrobials. Since isolation of vancomycin resistant enterococci has an important impact in terms of hospital infection control, vancomycin

  8. Identification and Antimicrobial Resistance of Enterococcus Spp. Isolated from the River and Coastal Waters in Northern Iran

    PubMed Central

    Hajiesmaili, Reza; Talebjannat, Maryam; Yahyapour, Yousef

    2014-01-01

    As fecal streptococci commonly inhabit the intestinal tract of humans and warm blooded animals, and daily detection of all pathogenic bacteria in coastal water is not practical, thus these bacteria are used to detect the fecal contamination of water. The present study examined the presence and the antibiotic resistance patterns of Enterococcus spp. isolated from the Babolrud River in Babol and coastal waters in Babolsar. Seventy samples of water were collected in various regions of the Babolrud and coastal waters. Isolated bacteria were identified to the species level using standard biochemical tests and PCR technique. In total, 70 Enterococcus spp. were isolated from the Babolrud River and coastal waters of Babolsar. Enterococcus faecalis (68.6%) and Enterococcus faecium (20%) were the most prevalent species. Resistance to chloramphenicol, ciprofloxacin, and tetracyclin was prevalent. The presence of resistant Enterococcus spp. in coastal waters may transmit resistant genes to other bacteria; therefore, swimming in such environments is not suitable. PMID:25525617

  9. Identification and antimicrobial resistance of Enterococcus spp. isolated from the river and coastal waters in northern Iran.

    PubMed

    Alipour, Majid; Hajiesmaili, Reza; Talebjannat, Maryam; Yahyapour, Yousef

    2014-01-01

    As fecal streptococci commonly inhabit the intestinal tract of humans and warm blooded animals, and daily detection of all pathogenic bacteria in coastal water is not practical, thus these bacteria are used to detect the fecal contamination of water. The present study examined the presence and the antibiotic resistance patterns of Enterococcus spp. isolated from the Babolrud River in Babol and coastal waters in Babolsar. Seventy samples of water were collected in various regions of the Babolrud and coastal waters. Isolated bacteria were identified to the species level using standard biochemical tests and PCR technique. In total, 70 Enterococcus spp. were isolated from the Babolrud River and coastal waters of Babolsar. Enterococcus faecalis (68.6%) and Enterococcus faecium (20%) were the most prevalent species. Resistance to chloramphenicol, ciprofloxacin, and tetracyclin was prevalent. The presence of resistant Enterococcus spp. in coastal waters may transmit resistant genes to other bacteria; therefore, swimming in such environments is not suitable.

  10. Description of Enterococcus canis sp. nov. from dogs and reclassification of Enterococcus porcinus Teixeira et al. 2001 as a junior synonym of Enterococcus villorum Vancanneyt et al 2001.

    PubMed

    De Graef, E M; Devriese, L A; Vancanneyt, M; Baele, M; Collins, M D; Lefebvre, K; Swings, J; Haesebrouck, F

    2003-07-01

    Strains from anal swabs and chronic otitis externa in dogs were shown to be phylogenetically related to the Enterococcus faecium species group. They shared a number of phenotypic characteristics with these species, but they could be easily differentiated by biochemical reactions. In addition, the canine strains were unusual in their nearly complete failure to grow on sodium azide-containing enterococci-selective media and in their Voges-Proskauer reactions (usually negative). By using 16S rRNA sequencing and DNA-DNA hybridization of representative strains, as well as tDNA interspacer gene PCR and SDS-PAGE of whole-cell proteins, the group of canine strains was shown to constitute a novel enterococcal species. The name Enterococcus canis sp. nov. is proposed for this species, with LMG 12316T (= CCUG 46666T) as the type strain. Concurrently, the taxonomic situation and nomenclatural position of Enterococcus porcinus were investigated. As no phenotypic or genotypic differences were found between this species and Enterococcus villorum, the name E. porcinus is considered to be a junior synonym of E. villorum.

  11. First case of vanA-positive Enterococcus mundtii in human urinary tract infection in Iran

    PubMed Central

    Sharifi-Rad, M.; Shadanpour, S.; van Belkum, A.; Soltani, A.; Sharifi-Rad, J.

    2016-01-01

    We cultured enterococci from urinary tract infections in Iranian hospitals. Seven different Enterococcus species (E. raffinosus, E. durans, E. hirae, E. avium, E. mundtii, E. faecium and E. faecalis) were found. Seven strains were vancomycin resistant, leading to an overall vancomycin resistance rate of 3.9%. The enterococcal infection rate was high and vancomycin-resistant enterococci incidence low. We report the first vanA-positive E. mundtii urinary tract infections. PMID:27081495

  12. Characterization of different food-isolated Enterococcus strains by MALDI-TOF mass fingerprinting.

    PubMed

    Quintela-Baluja, Marcos; Böhme, Karola; Fernández-No, Inmaculada C; Morandi, Stefano; Alnakip, Mohammed E; Caamaño-Antelo, Sonia; Barros-Velázquez, Jorge; Calo-Mata, Pilar

    2013-08-01

    Enterococcus is a controversial genus due to its great variability; this genus includes pathogenic strains, spoilage strains, and apparently safe strains including some probiotic strains. Previous studies focused on the characterization of strains of Enterococcus spp. involved in nosocomial infections. However, little research has been conducted on Enterococcus strains in foodstuffs. In the present work, 36 strains of different species of Enterococcus have been characterized by means of MALDI-TOF MS, resulting in highly specific mass spectral fingerprints. Characteristic peak masses common to certain bacterial species of Enterococcus have been identified. Thus, a peak at m/z 4426 ± 1 was assigned as a genus-specific biomarker. In addition, phyloproteomic relationships based on the mass spectral data were compared to the results of a phylogenetic analysis based on the 16S rRNA gene sequence. A better grouping at the species level was observed in the phyloproteomic tree, especially for the Enterococcus faecium group. Presumably, the assortment of some strains or ecotypes could be related to their ecological niche specialization. The approach described in this study leads the way toward the rapid and specific identification of different strains and species of Enterococcus in food based on molecular protein markers, aiming at the early detection of pathogenic strains and strains implicated in food poisoning or food spoilage.

  13. Enterococcal meningitis caused by Enterococcus casseliflavus. First case report

    PubMed Central

    Iaria, Chiara; Stassi, Giovanna; Costa, Gaetano Bruno; Di Leo, Rita; Toscano, Antonio; Cascio, Antonio

    2005-01-01

    Background Enterococcal meningitis is an uncommon disease usually caused by Enterococcus faecalis and Enterococcus faecium and is associated with a high mortality rate. Enterococcus casseliflavus has been implicated in a wide variety of infections in humans, but never in meningitis. Case presentation A 77-year-old Italian female presented for evaluation of fever, stupor, diarrhea and vomiting of 3 days duration. There was no history of head injury nor of previous surgical procedures. She had been suffering from rheumatoid arthritis for 30 years, for which she was being treated with steroids and methotrexate. On admission, she was febrile, alert but not oriented to time and place. Her neck was stiff, and she had a positive Kernig's sign. The patient's cerebrospinal fluid was opalescent with a glucose concentration of 14 mg/dl, a protein level of 472 mg/dl, and a white cell count of 200/μL with 95% polymorphonuclear leukocytes and 5% lymphocytes. Gram staining of CSF revealed no organisms, culture yielded E. casseliflavus. The patient was successfully treated with meropenem and ampicillin-sulbactam. Conclusions E. casseliflavus can be inserted among the etiologic agents of meningitis. Awareness of infection of central nervous system with Enterococcus species that possess an intrinsic vancomycin resistance should be increased. PMID:15649336

  14. Prevalence and antibiotic resistance of Enterococcus strains isolated from poultry.

    PubMed

    Stępień-Pyśniak, Dagmara; Marek, Agnieszka; Banach, Tomasz; Adaszek, Łukasz; Pyzik, Ewelina; Wilczyński, Jarosław; Winiarczyk, Stanisław

    2016-06-01

    The aim of this study was to evaluate the frequency of occurrence of bacteria of the genus Enterococcus in poultry, to identify them by means of matrixassisted laser desorption/ionisation time-of-flight mass spectrometry (MALDITOF MS), and to analyse the antimicrobial susceptibility of the isolated strains to the drugs most frequently used in poultry. The material for the bacteriological tests was obtained mainly from the heart (97%) of the birds investigated. Of a total of 2,970 samples tested, 911 (30.7%) tested positive for Enterococcus spp. Enterococci were detected in broilers (88.1%), laying hens (5.3%), turkeys (3.9%), breeding hens (2.2%), and geese (0.4%). The most commonly identified species were Enterococcus (E.) faecalis (74.7%), E. faecium (10.1%), E. gallinarum (5.5%), E. hirae (4.6%), and E. cecorum (4.1%). The most frequent resistance properties were resistance to sulphamethoxazole/trimethoprim (88%), tylosin (71.4%), enrofloxacin (69.4%), doxycycline (67.3%), and lincomycin/spectinomycin (56.1%). Only one vancomycin-resistant Enterococcus, E. cecorum from a broiler, was found.

  15. Microevolutionary Events Involving Narrow Host Plasmids Influences Local Fixation of Vancomycin-Resistance in Enterococcus Populations

    PubMed Central

    Freitas, Ana R.; Novais, Carla; Tedim, Ana P.; Francia, María Victoria; Baquero, Fernando; Peixe, Luísa; Coque, Teresa M.

    2013-01-01

    Vancomycin-resistance in enterococci (VRE) is associated with isolates within ST18, ST17, ST78 Enterococcus faecium (Efm) and ST6 Enterococcus faecalis (Efs) human adapted lineages. Despite of its global spread, vancomycin resistance rates in enterococcal populations greatly vary temporally and geographically. Portugal is one of the European countries where Tn1546 (vanA) is consistently found in a variety of environments. A comprehensive multi-hierarchical analysis of VRE isolates (75 Efm and 29 Efs) from Portuguese hospitals and aquatic surroundings (1996–2008) was performed to clarify the local dynamics of VRE. Clonal relatedness was established by PFGE and MLST while plasmid characterization comprised the analysis of known relaxases, rep initiator proteins and toxin-antitoxin systems (TA) by PCR-based typing schemes, RFLP comparison, hybridization and sequencing. Tn1546 variants were characterized by PCR overlapping/sequencing. Intra- and inter-hospital dissemination of Efm ST18, ST132 and ST280 and Efs ST6 clones, carrying rolling-circle (pEFNP1/pRI1) and theta-replicating (pCIZ2-like, Inc18, pHTβ-like, two pRUM-variants, pLG1-like, and pheromone-responsive) plasmids was documented. Tn1546 variants, mostly containing ISEf1 or IS1216, were located on plasmids (30–150 kb) with a high degree of mosaicism and heterogeneous RFLP patterns that seem to have resulted from the interplay between broad host Inc18 plasmids (pIP501, pRE25, pEF1), and narrow host RepA_N plasmids (pRUM, pAD1-like). TAs of Inc18 (ω-ε-ζ) and pRUM (Axe-Txe) plasmids were infrequently detected. Some plasmid chimeras were persistently recovered over years from different clonal lineages. This work represents the first multi-hierarchical analysis of VRE, revealing a frequent recombinatorial diversification of a limited number of interacting clonal backgrounds, plasmids and transposons at local scale. These interactions provide a continuous process of parapatric clonalization driving a full

  16. Enterococcus populations in artisanal Manchego cheese: biodiversity, technological and safety aspects.

    PubMed

    Nieto-Arribas, Pedro; Seseña, Susana; Poveda, Justa M; Chicón, Rosa; Cabezas, Lourdes; Palop, Llanos

    2011-08-01

    Enterococci represent a considerable proportion of the microbiota in Manchego cheeses. In this study, a total of 132 enterococci isolated from good quality Manchego cheeses from two dairies at different ripening times were genotypically characterized and identified using molecular techniques. Representative isolates from the clusters obtained after genotyping were assayed for some enzymatic activities considered to have a potential role in cheese ripening, and for 2,3-butanedione and acetoin production, evaluation of odor intensity and appearance in milk and safety evaluation. Enterococcus faecalis was the predominant specie, accounting for 81.8% of the total isolates, while Enterococcus faecium, Enterococcus hirae and Enterococcus avium were present in low proportions. The number of genotypes involved at each ripening time varied both between dairies and with the ripening times; genotype E. faecalis Q1 being present in almost all the samples from both dairies. Eight isolates showed a higher proteolytic activity and 3 isolates produced high quantities of acetoin-diacetyl, for which reason they are interesting from a technological standpoint. A low antibiotic resistance was found and almost all the strains were susceptible to clinically important antibiotics. On the contrary, only four isolates (E. faecalis C4W1 and N0W5, and E. faecium N32W1 and C16W2) did not harbor some of the virulence genes assayed.

  17. Environmental waters as a source of antibiotic-resistant Enterococcus species in Belgrade, Serbia.

    PubMed

    Veljović, Katarina; Popović, Nikola; Vidojević, Amarela Terzić; Tolinački, Maja; Mihajlović, Sanja; Jovčić, Branko; Kojić, Milan

    2015-09-01

    Despite the number of studies on antibiotic-resistant enterococci from Serbian clinical settings, there are no data about environmental contamination with these bacteria. Thus, this study investigated the prevalence of antibiotic-resistant enterococci in Belgrade, Serbia. Enterococcus species collected from ten surface water sites, including a lake, two major river systems, and springs, were tested. Among enterococci, we found single (21.7 %), double (17.4 %), and multiple antibiotic resistance patterns (56.3 %). Vancomycin-resistant strains were not found, indicating that their abundance in Belgrade is tightly linked to clinical settings. The multiple drug-resistant strains Enterococcus faecalis, Enterococcus faecium, and Enterococcus mundtii were frequently detected in the lake during the swimming season and in the rivers near industrial zones. We confirmed the presence of ermB, ermC, ant(6)-Ia, tetM, and tetL and mutations in gyrA genes. The phylogenetic analysis of 16S rRNA gene of E. faecium isolates that harbor esp gene classified them into two groups based on high-bootstraps scores in the tree analysis. Pulsed-field gel electrophoresis analysis of antibiotic-resistant enterococci revealed genomic similarity ranging from 75 to 100 %. This study indicates the importance of anthropogenic impact to the spread of antibiotic-resistant enterococci in environmental waters of Belgrade, Serbia.

  18. Enterococcus species diversity in fecal samples of wild marine species as determined by real-time PCR.

    PubMed

    Medeiros, Aline Weber; Blaese Amorim, Derek; Tavares, Maurício; de Moura, Tiane Martin; Franco, Ana Claudia; d'Azevedo, Pedro Alves; Frazzon, Jeverson; Frazzon, Ana Paula Guedes

    2017-02-01

    Analyses using culture-independent molecular techniques have improved our understanding of microbial composition. The aim of this work was to identify and quantify enterococci in fecal samples of wild marine species using real-time quantitative PCR. Seven Enterococcus species were examined in fecal DNA of South American fur seals (Arctocephalus australis), Subantarctic fur seals (Arctocephalus tropicalis), green turtles (Chelonia mydas), Magellanic penguins (Spheniscus magellanicus), snowy-crowned tern (Sterna trudeaui), white-backed stilt (Himantopus melanurus), white-chinned petrels (Procellaria aequinoctialis), red knot (Calidris canutus), and black-browed albatross (Thalassarche melanophris). All Enterococcus species evaluated were detected in all fecal samples of wild marine species, with a concentration ranging between 10(6) and 10(12) copies/ng of total DNA. Differences in the enterococci distribution were observed. Enterococcus faecalis and Enterococcus mundtii were most abundant in marine mammals. Enterococcus faecalis was frequent in green turtle, Magellanic penguin, snowy-crowned tern, red knot, and black-browed albatross. Enterococcus hirae and Enterococcus gallinarum showed elevated occurrence in white-backed stilt, and Enterococcus faecium in white-chinned petrel. This study showed highest diversity of enterococci in feces of wild marine species than currently available data, and reinforced the use of culture-independent analysis to help us to enhance our understanding of enterococci in gastrointestinal tracts of wild marine species.

  19. Characterization of Enterococcus spp. from human and animal feces using 16S rRNA sequences, the esp gene, and PFGE for microbial source tracking in Korea.

    PubMed

    Kim, Sei-Yoon; Lee, Jung Eun; Lee, Sunghee; Lee, Hee Tae; Hur, Ho-Gil; Ko, Gwangpyo

    2010-05-01

    Contamination from human and animal fecal waste is a primary cause of water pollution. Microbial source tracking (MST) may be a useful tool for high-quality environmental management and for assessing human health risks associated with water pollution. The goal of this study was to evaluate Enterococcus spp. as a target organism for MST. Thirty-four fecal samples were collected from five different sources (human, chicken, pig, cow, and goose) in South Korea. In total, 237 Enterococcus spp. were isolated from feces using membrane- Enterococcus indoxyl-beta-d-glucoside agar. The 16S rRNA gene and the whole genome were analyzed using nucleic acid sequencing and pulsed-field gel electrophoresis (PFGE), respectively. Both phylogenetic analysis and principal coordinate analysis using UniFrac were performed on the nucleic acid sequences of the 16S rRNA gene. According to P-tests from UniFrac, significant differences existed between Enterococcus spp. isolated from human feces and those from animal feces. In addition, we evaluated whether the esp gene of Enterococcus faecium could be a specific target for Enterococcus spp. isolated from human feces. Of 58 E. faecium isolates tested, only three were esp-positive. The specificity of the esp gene of E. faecium isolated from human feces was 100%, but the sensitivity was <10%. These results suggest that Enterococcus spp. have different molecular characteristics according to their fecal source and that these characteristics can be further identified by analyzing the esp gene and 16S rRNA sequences, whereas PFGE provides limited information on the fecal sources of Enterococcus spp.

  20. Clinical epidemiology of vancomycin-resistant Enterococcus gallinarum and Enterococcus casseliflavus bloodstream infections.

    PubMed

    Britt, Nicholas S; Potter, Emily M

    2016-06-01

    This study aimed to evaluate the clinical outcomes of vancomycin-resistant enterococcal bloodstream infections (VRE BSI) caused by Enterococcus gallinarum or Enterococcus casseliflavus. Variables associated with treatment failure were determined and treatment options were compared. This was a national retrospective study of hospitalised Veterans Affairs patients with non-faecium, non-faecalis VRE BSI. The primary outcome was treatment failure, defined as a composite of: (i) 30-day all-cause mortality; (ii) microbiological failure; and (iii) 30-day VRE BSI recurrence. Stepwise Poisson regression was conducted to determine variables associated with treatment failure. In total, 48 patients were included, with 29 cases (60.4%) caused by E. gallinarum and 19 cases (39.6%) caused by E. casseliflavus. Among these cases, 20 (41.7%) were treated with an anti-VRE agent (linezolid or daptomycin) and 28 (58.3%) were treated with an anti-enterococcal β-lactam. Overall, 30-day mortality was 10.4% (5/48) and composite treatment failure was 39.6% (19/48). In multivariate analysis, treatment with an anti-enterococcal β-lactam was associated with increased treatment failure in comparison with anti-VRE therapy (adjusted risk ratio = 1.73, 95% confidence interval 1.06-4.97; P = 0.031). Overall, treatment with linezolid or daptomycin for vancomycin-resistant E. gallinarum or E. casseliflavus BSI resulted in improved clinical outcomes in comparison with anti-enterococcal β-lactam treatment.

  1. Diversity of Antibiotic Resistance Genes in Enterococcus Strains Isolated from Ready-to-Eat Meat Products.

    PubMed

    Chajęcka-Wierzchowska, Wioleta; Zadernowska, Anna; Łaniewska-Trokenheim, Łucja

    2016-10-25

    The objective of the study was to answer the question of whether the ready-to-eat meat products can pose indirect hazard for consumer health serving as reservoir of Enterococcus strains harboring tetracyclines, aminoglycosides, and macrolides resistance genes. A total of 390 samples of ready-to-eat meat products were investigated. Enterococcus strains were found in 74.1% of the samples. A total of 302 strains were classified as: Enterococcus faecalis (48.7%), Enterococcus faecium (39.7%), Enterococcus casseliflavus (4.3%), Enterococcus durans (3.0%), Enterococcus hirae (2.6%), and other Enterococcus spp. (1.7%). A high percentage of isolates were resistant to streptomycin high level (45%) followed by erythromycin (42.7%), fosfomycin (27.2%), rifampicin (19.2%), tetracycline (36.4%), tigecycline (19.9%). The ant(6')-Ia gene was the most frequently found gene (79.6%). Among the other genes that encode aminoglycosides-modifying enzymes, the highest portion of the strains had the aac(6')-Ie-aph(2'')-Ia (18.5%) and aph(3'')-IIIa (16.6%), but resistance of isolates from food is also an effect of the presence of aph(2'')-Ib, aph(2'')-Ic, aph(2'')-Id genes. Resistance to tetracyclines was associated with the presence of tetM (43.7%), tetL (32.1%), tetK (14.6%), tetW (0.7%), and tetO (0.3%) genes. The ermB and ermA genes were found in 33.8% and 18.9% of isolates, respectively. Nearly half of the isolates contained a conjugative transposon of the Tn916/Tn1545 family. Enterococci are widely present in retail ready-to-eat meat products. Many isolated strains (including such species as E. casseliflavus, E. durans, E. hirae, and Enterococcus gallinarum) are antibiotic resistant and carry transferable resistance genes.

  2. Antimicrobial resistance in Enterococcus strains isolated from healthy domestic dogs.

    PubMed

    Bertelloni, Fabrizio; Salvadori, Claudia; Lotti, Giulia; Cerri, Domenico; Ebani, Valentina Virginia

    2016-12-15

    Enterococci are opportunistic bacteria that cause severe infections in animals and humans, capable to acquire, express, and transfer antimicrobial resistance. Susceptibility to 21 antimicrobial agents was tested by the disk diffusion method in 222 Enterococcus spp. strains isolated from the fecal samples of 287 healthy domestic dogs. Vancomycin and ampicillin minimum inhibitory concentrations (MICs) and high-level aminoglycoside resistance (HLAR) tests were also performed. Isolates showed resistance mainly to streptomycin (88.7%), neomycin (80.6%), and tetracycline (69.4%). Forty-two (18.9%) isolates showed an HLAR to streptomycin and 15 (6.7%) to gentamicin. Vancomycin and ampicillin MIC values showed 1 and 18 resistant strains, respectively. One hundred and thirty-six (61.2%) strains were classified as multidrug resistant and six (2.7%) strains as possibly extensively drug-resistant bacteria. Enterococcus faecium and Enterococcus faecalis were the most prevalent antimicrobial resistant species. Companion animals, which often live in close contact with their owners and share the same environment, represent a serious source of enterococci resistant to several antibiotics; for this reason, they may be a hazard for public health by providing a conduit for the entrance of resistance genes into the community.

  3. Characterization of veterinary hospital-associated isolates of Enterococcus species in Korea.

    PubMed

    Chung, Yeon Soo; Kwon, Ka Hee; Shin, Sook; Kim, Jae Hong; Park, Yong Ho; Yoon, Jang Won

    2014-03-28

    Possible cross-transmission of hospital-associated enterococci between human patients, medical staff, and hospital environments has been extensively studied. However, limited information is available for veterinary hospital-associated Enterococcus isolates. This study investigated the possibility of cross-transmission of antibiotic-resistant enterococci between dog patients, their owners, veterinary staff, and hospital environments. Swab samples (n =46 5) were obtained from five veterinary hospitals in Seoul, Korea, during 2011. Forty-three Enterococcus strains were isolated, representing seven enterococcal species. E. faecalis and E. faecium were the most dominant species (16 isolates each, 37.2%). Although slight differences in the antibiotic resistance profiles were observed between the phenotypic and the genotypic data, our antibiogram analysis demonstrated high prevalence of the multiple drug-resistant (MDR) isolates of E. faecalis (10/16 isolates, 62.5%) and E. faecium (12/16 isolates, 75.0%). Pulsed-field gel electrophoretic comparison of the MDR isolates revealed three different clonal sets of E. faecalis and a single set of E. faecium, which were isolated from different sample groups or dog patients at the same or two separate veterinary hospitals. These results imply a strong possibility of cross-transmission of the antibiotic-resistant enterococcal species between animal patients, owners, veterinary staff, and hospital environments.

  4. The life and times of the Enterococcus.

    PubMed Central

    Murray, B E

    1990-01-01

    Enterococci are important human pathogens that are increasingly resistant to antimicrobial agents. These organisms were previously considered part of the genus Streptococcus but have recently been reclassified into their own genus, called Enterococcus. To date, 12 species pathogenic for humans have been described, including the most common human isolates, Enterococcus faecalis and E. faecium. Enterococci cause between 5 and 15% of cases of endocarditis, which is best treated by the combination of a cell wall-active agent (such as penicillin or vancomycin, neither of which alone is usually bactericidal) and an aminoglycoside to which the organism is not highly resistant; this characteristically results in a synergistic bactericidal effect. High-level resistance (MIC, greater than or equal to 2,000 micrograms/ml) to the aminoglycoside eliminates the expected bactericidal effect, and such resistance has now been described for all aminoglycosides. Enterococci can also cause urinary tract infections; intraabdominal, pelvic, and wound infections; superinfections (particularly in patients receiving expanded-spectrum cephalosporins); and bacteremias (often together with other organisms). They are now the third most common organism seen in nosocomial infections. For most of these infections, single-drug therapy, most often with penicillin, ampicillin, or vancomycin, is adequate. Enterococci have a large number of both inherent and acquired resistance traits, including resistance to cephalosporins, clindamycin, tetracycline, and penicillinase-resistant penicillins such as oxacillin, among others. The most recent resistance traits reported are penicillinase resistance (apparently acquired from staphylococci) and vancomycin resistance, both of which can be transferred to other enterococci. It appears likely that we will soon be faced with increasing numbers of enterococci for which there is no adequate therapy. PMID:2404568

  5. MALDI-TOF mass spectrometry as a useful tool for identification of Enterococcus spp. from wild birds and differentiation of closely related species.

    PubMed

    Stępień-Pyśniak, Dagmara; Hauschild, Tomasz; Różański, Paweł; Marek, Agnieszka

    2017-03-13

    The aim of this study was to explore the accuracy and feasibility of Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) in identifying bacteria from environmental sources, as compared to rpoA gene sequencing, and to evaluate the occurrence of bacteria of the genus Enterococcus in wild birds. In addition, a phyloproteomic analysis of certain Enterococcus species with spectral relationships was performed. The enterococci were isolated from 25 species of wild birds in central Europe (Poland). Proteomic (MALDI-TOF MS) and genomic (rpoA gene sequencing) methods were used to identify isolates. Using MALDI-TOF MS, all 54 (100%) isolates were identified as Enterococcus spp. Among these, 51 (94.4%) isolates were identified to the species level - log(score) > or =2.0, and three isolates (5.6%) were identified at a level of probable genus identification - log(score) 1.88-1.927. Phylogenetic analysis based on rpoA sequences confirmed that all enterococci had been correctly identified. Enterococcus faecalis was the most prevalent enterococcal species (50%) and Enterococcus faecium (33.3%) the second most frequent species, followed by Enterococcus hirae (9.3%), Enterococcus durans (3.7%) and Enterococcus casseliflavus (3.7%). The phyloproteomic analysis of the spectral profiles of the isolates showed that MALDI-TOF MS is able to differentiate among similar species of the genus Enterococcus.

  6. [Investigation of the efficacy of some disinfectants against nosocomial Staphylococcus aureus and Enterococcus spp. isolates].

    PubMed

    Eryılmaz, Müjde; Akın, Ahmet; Arıkan Akan, Ozay

    2011-07-01

    Nosocomial infections which exhibit an increasing trend worldwide, are important contributors to morbidity and mortality. Most bacteria that cause nosocomial infections can retain their viability even after exposure to disinfectants in routine practice. This study was conducted to determine the susceptibilities of nosocomial Staphylococcus aureus and Enterococcus spp. isolates to various disinfectants. A total of 30 S.aureus [16 were methicillin-resistant (MRSA), 14 were methicillin-susceptible (MSSA)] and 21 Enterococcus spp. (13 E.faecalis, 7 E.faecium, 1 non-typable Enterococcus spp.) strains isolated from clinical samples of hospitalized patients as nosocomial infection agents in the Central Microbiology Laboratory of Ibn-i Sina Hospital, Ankara University, Faculty of Medicine, were included in the study. Glutaraldehyde (2% wt/vol), chlorhexidine gluconate (4% wt/vol), 2-propanol (70% vol/vol), povidone iodine (7.5% wt/vol), povidone iodine (10% wt/vol) and hydrogen peroxide (3% wt/vol) susceptibilities of the isolates were investigated by quantitative suspension test at contact times of 3, 5, and 10 minutes. All of the isolates were found susceptible to glutaraldehyde (2%), chlorhexidine gluconate (4%), povidone iodine (7.5%), povidone iodine (10%) and 2-propanol (70%) at all tested contact times. However, 12 S.aureus (5 MSSA, 7 MRSA) and 3 enterococci (2 E.faecium, 1 E.faecalis) isolates were found susceptible to hydrogen peroxide (3%) at 3 minutes contact time; 11 S.aureus (4 MSSA, 7 MRSA) and 7 E.faecalis isolates were found susceptible at 5 minutes contact time, and 6 S.aureus (4 MSSA, 2 MRSA) and 3 enterococci (1 E.faecium, 2 E.faecalis) isolates were found susceptible at 10 minutes contact time. One MSSA and 8 enterococci (4 E.faecium, 3 E.faecalis, 1 Enterococcus spp.) isolates were found resistant to hydrogen peroxide (3%) at 10 minutes contact time. In conclusion, glutaraldehyde (2%), chlorhexidine gluconate (4%), povidone iodine (7.5%), povidone

  7. Macrolide, glycopeptide resistance and virulence genes in Enterococcus species isolates from dairy cattle.

    PubMed

    Iweriebor, Benson C; Obi, Larry C; Okoh, Anthony I

    2016-07-01

    The genus Enterococcus is known to possess the capacity to acquire and disseminate antimicrobial resistant determinants alongside the ability to produce various virulence genes that enables it to establish infections. We assessed the prevalence and antibiogram profiles of Enterococcus spp. in faecal samples of dairy cattle. Faecal swab samples were collected from 400 dairy cattle from two commercial cattle farms in two rural communities in the Eastern Cape, South Africa. Confirmation of enterococci isolates was carried out by PCR targeting of the tuf gene. Species delineation was by species-specific primers targeting the superoxide dismutase (sod A) gene in a multiplex PCR assay. Isolates were screened for the presence of the following virulence genes (ace, gel E, esp, efa A, cyl A and hyl E) and antimicrobial resistance determinants to erythromycin, vancomycin and streptomycin were evaluated molecularly. A total of 340 isolates were confirmed as belonging to the genus Enterococcus . Species distribution among the isolates consisted of Enterococcus faecium (52.94 %) and Enterococcus durans (23.53 %) in preponderance compared to the three other species, namely Enterococcus faecalis (8.8 %), Enterococcus hirae (8.6 %) and Enterococcus casseliflavus (5.9 %). All were resistant to vancomycin, while 99 % showed resistance to aminoglycoside and 94 % to macrolide. Three virulence genes (ace, gel E and esp) were detected in almost all the confirmed isolates. The resistance determinants van B (19.7 %), van C1 (25 %), van C2/3 (26.3 %) erm B (40.29 %) and str A (50.88 %) were detected among the isolates. A high prevalence of multidrug-resistant enterococci isolates was detected in this study and the genetic repertoire to survive in the presence of antimicrobial agents was present in these organisms.

  8. Characterization of aminoglycoside resistance and virulence genes among Enterococcus spp. isolated from a hospital in China.

    PubMed

    Li, Wanxiang; Li, Jing; Wei, Quhao; Hu, Qingfeng; Lin, Xiaowei; Chen, Mengquan; Ye, Renji; Lv, Huoyang

    2015-03-11

    This study investigated the aminoglycoside resistance phenotypes and genotypes, as well as the prevalence of virulence genes, in Enterococcus species isolated from clinical patients in China. A total of 160 enterococcal isolates from various clinical samples collected from September 2013 to July 2014 were identified to the species level using the VITEK-2 COMPACT system. The antimicrobial susceptibilities of the identified Enterococcus strains were determined by the Kirby-Bauer (K-B) disc diffusion method. PCR-based assays were used to detect the aminoglycoside resistance and virulence genes in all enterococcal isolates. Of 160 Enterococcus isolates, 105 were identified as E. faecium, 35 as E. faecalis, and 20 isolates were classified as "other" Enterococcus species. High-level aminoglycoside resistance (HLAR) for gentamicin, streptomycin, and both antibiotics was identified in 58.8, 50, and 34.4% of strains, respectively. The most common virulence gene (50.6% of isolates) was efaA, followed by asa1 (28.8%). The most prevalent aminoglycoside resistance genes were aac(6')-Ie-aph(2''), aph(2')-Id, aph(3')-IIIa, and ant(6')-Ia, present in 49.4%, 1.3%, 48.8% and 31.3% of strains, respectively. Overall, E. faecium and E. faecalis were most frequently associated with hospital-acquired enterococcal infections in Zhejiang Province. All aminoglycoside resistance genes, except aph(2'')-Id, were significantly more prevalent in HLAR strains than amongst high level aminoglycoside susceptible (HLAS) strains, while there was no significant difference between HLAR and HLAS strains in regard to the prevalence of virulence genes, apart from esp, therefore, measures should be taken to manage infections caused by multi-drug resistant Enterococcus species.

  9. Detection of vanA-Containing Enterococcus Species in Faecal Microbiota of Gilthead Seabream (Sparus aurata)

    PubMed Central

    Barros, Joana; Andrade, Margarida; Radhouani, Hajer; López, Maria; Igrejas, Gilberto; Poeta, Patricia; Torres, Carmen

    2012-01-01

    Vancomycin-resistant Enterococcus faecalis, E. faecium and E. durans isolates with the genotype vanA were detected in 7 of 118 faecal samples (5.9%) of natural gilthead seabream recovered off the coast of Portugal, and one vancomycin-resistant isolate/sample was further characterized. The genes erm(B), tet(L), tet(M), aac(6′)-aph(2″), aph(3′)-IIIa and/or ant(6)-Ia were identified in most of the 7 vancomycin-resistant enterococci. Sequence types ST273, ST313 and ST76 were detected in three E. faecium isolates and ST6 in two E. faecalis isolates. VanA-containing enterococci are suggested to be disseminated in fish in marine ecosystems close to areas of human activity. PMID:22641152

  10. Prevalence and antibiotic resistance of Enterococcus spp. isolated from retail cheese, ready-to-eat salads, ham, and raw meat.

    PubMed

    Pesavento, G; Calonico, C; Ducci, B; Magnanini, A; Lo Nostro, A

    2014-08-01

    Food specimens were analyzed in order to research Enterococcus spp.: 636 samples of raw meat (227 beef, 238 poultry, and 171 pork), 278 samples of cheese (110 fresh soft cheese and 168 mozzarella cheese), 214 samples of ready-to-eat salads, and 187 samples of ham. 312 strains of Enterococcus spp samples were isolated, then identified and submitted to susceptibility tests against 11 antimicrobial agents. The predominant species were Enterococcus faecalis in raw meat and Enterococcus faecium in retail products. Low percentages of microorganisms were resistant to vancomycin (3.53%), teicoplanin (2.24%), linezolid (0.32%), and amoxicillin in combination with clavulanic acid (0.32%). A high percentage of resistance was noted in E. faecalis at high level gentamicin (21.9%) and tetracycline (60.6%). In general, strains of E. faecalis were more resistant than E. faecium. Enterococci should be considered not only potential pathogens, but also a reservoir of genes encoding antibiotic resistance which can be transferred to other microorganisms. Continuous monitoring of their incidence and emerging resistance is important in order to identify foods which potentially represent a real risk to the population, and to ensure effective treatment of human enterococcal infections.

  11. Diversity, distribution and antibiotic resistance of Enterococcus spp. recovered from tomatoes, leaves, water and soil on U.S. Mid-Atlantic farms.

    PubMed

    Micallef, Shirley A; Goldstein, Rachel E Rosenberg; George, Ashish; Ewing, Laura; Tall, Ben D; Boyer, Marc S; Joseph, Sam W; Sapkota, Amy R

    2013-12-01

    Antibiotic-resistant enterococci are important opportunistic pathogens and have been recovered from retail tomatoes. However, it is unclear where and how tomatoes are contaminated along the farm-to-fork continuum. Specifically, the degree of pre-harvest contamination with enterococci is unknown. We evaluated the prevalence, diversity and antimicrobial susceptibilities of enterococci collected from tomato farms in the Mid-Atlantic United States. Tomatoes, leaves, groundwater, pond water, irrigation ditch water, and soil were sampled and tested for enterococci using standard methods. Antimicrobial susceptibility testing was performed using the Sensititre microbroth dilution system. Enterococcus faecalis isolates were characterized using amplified fragment length polymorphism to assess dispersal potential. Enterococci (n = 307) occurred in all habitats and colonization of tomatoes was common. Seven species were identified: Enterococcus casseliflavus, E. faecalis, Enterococcus gallinarum, Enterococcus faecium, Enterococcus avis, Enterococcus hirae and Enterococcus raffinosus. E. casseliflavus predominated in soil and on tomatoes and leaves, and E. faecalis predominated in pond water. On plants, distance from the ground influenced presence of enterococci. E. faecalis from samples within a farm were more closely related than those from samples between farms. Resistance to rifampicin, quinupristin/dalfopristin, ciprofloxacin and levofloxacin was prevalent. Consumption of raw tomatoes as a potential exposure risk for antibiotic-resistant Enterococcus spp. deserves further attention.

  12. A CRITICAL EVALUATION OF A FLOW CYTOMETER USED FOR DETECTING ENTEROCOCCUS FAECIUM AND ENTEROCOCCUS FAECALIS IN RECREATIONAL WATERS

    EPA Science Inventory

    The current U. S. Environmental Protection Agency-approved method for Enterococci (Method 1600) in recreational water is a membrane filter (MF) method that takes 24 hours to obtain results. If the recreational water is not in compliance with the standard, the risk of exposure to...

  13. Evaluation of species-specific PCR, Bruker MS, VITEK MS and the VITEK 2 system for the identification of clinical Enterococcus isolates.

    PubMed

    Fang, H; Ohlsson, A-K; Ullberg, M; Ozenci, V

    2012-11-01

    The purpose of this investigation was to compare the performance of species-specific polymerase chain reaction (PCR), matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and phenotypic identification systems for the identification of Enterococcus species. A total of 132 clinical isolates were investigated by the following: (1) a multiplex real-time PCR assay targeting ddl Enterococcus faecium, ddl Enterococcus faecalis, vanC1 and vanC2/C3 genes, and a high-resolution melting (HRM) analysis of the groESL gene for the differentiation of Enterococcus casseliflavus and Enterococcus gallinarum; (2) Bruker MS; (3) VITEK MS; and (4) the VITEK 2 system. 16S rRNA gene sequencing was used as a reference method in the study. The 132 isolates were identified as 32 E. faecalis, 63 E. faecium, 16 E. casseliflavus and 21 E. gallinarum. The multiplex PCR, Bruker MS and VITEK MS were able to identify all the isolates correctly at the species level. The VITEK 2 system could identify 131/132 (99.2 %) and 121/132 (91.7 %) of the isolates at the genus and species levels, respectively. The HRM-groESL assay identified all (21/21) E. gallinarum isolates and 81.3 % (13/16) of the E. casseliflavus isolates. The PCR methods described in the present study are effective in identifying the enterococcal species. MALDI-TOF MS is a rapid, reliable and cost-effective identification technique for enterococci. The VITEK 2 system is less efficient at detecting non-faecalis and non-faecium Enterococcus species.

  14. Enterococcus phages as potential tool for identifying sewage inputs in the Great Lakes region

    USGS Publications Warehouse

    ,; K.Vijayavel,; Byappanahalli, Muruleedhara N.; J. Ebdon,; ,; H. Taylor,; ,; Whitman, Richard L.; ,; D.R. Kashian,

    2014-01-01

    Bacteriophages are viruses living in bacteria that can be used as a tool to detect fecal contamination in surface waters around the world. However, the lack of a universal host strain makes them unsuitable for tracking fecal sources. We evaluated the suitability of two newly isolated Enterococcus host strains (ENT-49 and ENT-55) capable for identifying sewage contamination in impacted waters by targeting phages specific to these hosts. Both host strains were isolated from wastewater samples and identified as E. faecium by 16S rRNA gene sequencing. Occurrence of Enterococcus phages was evaluated in sewage samples (n = 15) from five wastewater treatment plants and in fecal samples from twenty-two species of wild and domesticated animals (individual samples; n = 22). Levels of Enterococcus phages, F + coliphages, Escherichia coli and enterococci were examined from four rivers, four beaches, and three harbors. Enterococcus phages enumeration was at similar levels (Mean = 6.72 Log PFU/100 mL) to F + coliphages in all wastewater samples, but were absent from all non-human fecal sources tested. The phages infecting Enterococcus spp. and F + coliphages were not detected in the river samples (detection threshold < 10 PFU/100 mL), but were present in the beach and harbor samples (range = 1.83 to 2.86 Log PFU/100 mL). Slightly higher concentrations (range = 3.22 to 3.69 Log MPN/100 mL) of E. coli and enterococci when compared to F + coliphages and Enterococcus phages, were observed in the river, beach and harbor samples. Our findings suggest that the bacteriophages associated with these particular Enterococcus host strains offer potentially sensitive and human-source specific indicators of enteric pathogen risk.

  15. Antibacterial efficacy of nisin, pediocin 34 and enterocin FH99 against L. monocytogenes, E. faecium and E. faecalis and bacteriocin cross resistance and antibiotic susceptibility of their bacteriocin resistant variants.

    PubMed

    Kaur, Gurpreet; Singh, Tejinder Pal; Malik, Ravinder Kumar; Bhardwaj, Arun; De, Sachinandan

    2014-02-01

    The bacteriocin susceptibility of Listeria monocytogenes MTCC 657, Enterococcus faecium DSMZ 20477, E. faecium VRE, and E. faecalis ATCC 29212 and their corresponding bacteriocin resistant variants was assessed. The single and combined effect of nisin and pediocin 34 and enterocin FH99 bacteriocins produced by Pediococcus pentosaceus 34, and E. faecium FH99, respectively, was determined. Pediocin34 proved to be more effective in inhibiting L. monocytogenes MTCC 657. A greater antibacterial effect was observed against E. faecium DSMZ 20477 and E. faecium (VRE) when the a combination of nisin, pediocin 34 and enterocin FH99 were used whereas in case of L. monocytogenes MTCC 657 a combination of pediocin 34 and enterocin FH99 was more effective in reducing the survival of pathogen. Bacteriocin cross-resistance and the antibiotic susceptibility of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class and also the acquired resistance to bacteriocins can modify the antibiotic susceptibility/resistance profile of the bacterial species used in the study. According to the hydrophobicity nisin resistant variant of L. monocytogenes was more hydrophobic (p < 0.001), whereas the pediocin 34 and enterocin FH99 resistant variants were less hydrophobic than the wild type strain. Nisin, pediocin 34 and enterocin FH99 resistant variants of E. faecium DSMZ 20477 and E. faecium VRE were less hydrophobic than their wild type counterparts. Nisin resistant E. faecalis ATCC 29212 was less hydrophobic than its wild type counterpart.

  16. A novel method for simultaneous Enterococcus species identification/typing and van genotyping by high resolution melt analysis.

    PubMed

    Gurtler, Volker; Grando, Danilla; Mayall, Barrie C; Wang, Jenny; Ghaly-Derias, Shahbano

    2012-09-01

    In order to develop a typing and identification method for van gene containing Enterococcus faecium, two multiplex PCR reactions were developed for use in HRM-PCR (High Resolution Melt-PCR): (i) vanA, vanB, vanC, vanC23 to detect van genes from different Enterococcus species; (ii) ISR (intergenic spacer region between the 16S and 23S rRNA genes) to detect all Enterococcus species and obtain species and isolate specific HRM curves. To test and validate the method three groups of isolates were tested: (i) 1672 Enterococcus species isolates from January 2009 to December 2009; (ii) 71 isolates previously identified and typed by PFGE (pulsed-field gel electrophoresis) and MLST (multi-locus sequence typing); and (iii) 18 of the isolates from (i) for which ISR sequencing was done. As well as successfully identifying 2 common genotypes by HRM from the Austin Hospital clinical isolates, this study analysed the sequences of all the vanB genes deposited in GenBank and developed a numerical classification scheme for the standardised naming of these vanB genotypes. The identification of Enterococcus faecalis from E. faecium was reliable and stable using ISR PCR. The typing of E. faecium by ISR PCR: (i) detected two variable peaks corresponding to different copy numbers of insertion sequences I and II corresponding to peak I and II respectively; (ii) produced 7 melt profiles for E. faecium with variable copy numbers of sequences I and II; (iii) demonstrated stability and instability of peak heights with equal frequency within the patient sample (36.4±4.5 days and 38.6±5.8 days respectively for 192 patients); (iv) detected ISR-HRM types with as much discrimination as PFGE and more than MLST; and (v) detected ISR-HRM types that differentiated some isolates that were identical by PFGE and MLST. In conjunction with the rapid and accurate van genotyping method described here, this ISR-HRM typing and identification method can be used as a stable identification and typing method with

  17. Performance of Vitek 2 for antimicrobial susceptibility testing of Staphylococcus spp. and Enterococcus spp.

    PubMed

    Bobenchik, April M; Hindler, Janet A; Giltner, Carmen L; Saeki, Sandra; Humphries, Romney M

    2014-02-01

    Vitek 2 (bioMérieux, Inc., Durham, NC) is a widely used commercial antimicrobial susceptibility testing system. We compared MIC results obtained by Vitek 2 to those obtained by the Clinical and Laboratory Standards Institute (CLSI) broth microdilution (BMD) reference method for 134 staphylococcal and 84 enterococcal clinical isolates. Nineteen agents were evaluated, including all those available on Vitek 2 for testing staphylococci and enterococci. The resistance phenotypes tested included methicillin-resistant Staphylococcus aureus (MRSA) (n = 58), S. aureus with inducible clindamycin resistance (ICR) (n = 30), trimethoprim-sulfamethoxazole-resistant MRSA (n = 10), vancomycin-resistant Enterococcus (n = 37), high-level gentamicin-resistant Enterococcus (n = 15), linezolid-resistant Enterococcus (n = 5), and daptomycin-nonsusceptible Enterococcus faecalis (n = 6). For the staphylococci, there was 98.9% categorical agreement (CA). There was one very major error (VME) for gentamicin in a Staphylococcus hominis isolate, six VMEs for inducible clindamycin in S. aureus isolates, and two major errors (ME) for daptomycin in an S. aureus and a Staphylococcus epidermidis isolate. For enterococci, there was 97.3% CA. Two VMEs were observed for daptomycin in isolates of E. faecalis and 2 ME, 1 for high-level gentamicin resistance and 1 for nitrofurantoin, in E. faecium isolates. Overall, there was 98.3% CA and 99% essential agreement for the testing of staphylococci and enterococci by the Vitek 2. With the exception of detecting ICR in S. aureus, Vitek 2 performed reliably for antimicrobial susceptibility testing of staphylococci and enterococci.

  18. Biotechnological and safety characterization of Enterococcus lactis, a recently described species of dairy origin.

    PubMed

    Morandi, Stefano; Silvetti, Tiziana; Brasca, Milena

    2013-01-01

    The biotechnological and safety properties of a recently described enterococcal species, Enterococcus lactis, were investigated. With regard to the technological properties, in milk all the strains tested had weak acidifying and proteolytic activities, generally medium reduction activity over 24 h (-102 mV < Eh < -2 mV) and low lipolytic activity on tributyrin agar. The isolates were tested for resistance against 14 antibiotics and none of the studied strains were classified as resistant to clinically important antibiotics such as ampicillin, erythromycin, penicillin G, tetracycline and vancomycin. Furthermore, PCR-based detection did not identify any of the common genetic determinants for vancomycin, tetracycline and erythromycin resistance. The E. lactis strains showed good survival in simulated in vitro digestion and were able to inhibit the growth of Enterococcus durans, Enterococcus faecalis, Enterococcus faecium, Clostridium sporogenes, Clostridium tyrobutyricum and Pseudomonas syringae. Screening for enterocin structural genes showed that all isolates harboured the entP gene. The presence of nine virulence factor genes (cylA, asa1, gelE, hyl, esp, ace, efaA, hdc and tdc) was investigated by PCR and no virulence determinants were detected. This study highlights that the recently described E. lactis may be a potential source of novel strains with interesting features that could be used for fermented dairy foods.

  19. Bacteriocin from Enterococcus faecium NRRL B-30746 (E 50-52) kills Campylobacter jejuni in broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effectiveness of antibiotics in resolving bacterial infections has been compromised by the increased prevalence and magnitude of antibiotic resistance. In our efforts to identify new effective antimicrobials, bacteria isolated from poultry intestinal content were screened for bacteriocin synthe...

  20. Antimicrobial resistance and virulence traits in Enterococcus strains isolated from dogs and cats.

    PubMed

    Iseppi, Ramona; Messi, Patrizia; Anacarso, Imacolata; Bondi, Moreno; Sabia, Carla; Condò, Carla; de Niederhausern, Simona

    2015-07-01

    We investigated presence and prevalence of antibiotic-resistances and other biological characters in enterococci isolated from faeces of healthy dogs and cats because these microorganisms represent important human and veterinary pathogens/opportunists, and a significant burden for healthcare systems. In all samples (n=115) we detected enterococci, with a predominance of Enterococcus faecium (42; 36.5%) and Enterococcus faecalis (36; 31.3%) species, endowed with virulence traits and multidrug-resistance. The two predominant resistance patterns (erythromycin, tetracycline) were examined by polymerase chain reaction for tet and erm genes. Only tetM for tetracycline, and ermA and ermB for erythromycin were detected. PCR for gelatinase gene (gelE) was positive in 62.6% of isolates, but only 26.1% produce gelatinase suggesting the existence of silent genes. efaAfs and efaAfm genes were found in E. faecalis and E. faecium respectively. 89.6% of isolates produced bacteriocin-like substances with a prevailing action against Listeria genus and, among these, 33.9% were positive for the bacteriocin structural genes entA, entL50 or entP. According to our study, pet animals can be considered a reservoir of potentially pathogenic enterococci and we cannot exclude that those microorganisms may be responsible for opportunistic infections in high-risk pet owners.

  1. Multiple-Antibiotic Resistance of Enterococcus spp. Isolated from Commercial Poultry Production Environments

    PubMed Central

    Hayes, Joshua R.; English, Linda L.; Carr, Lewis E.; Wagner, David D.; Joseph, Sam W.

    2004-01-01

    The potential impact of food animals in the production environment on the bacterial population as a result of antimicrobial drug use for growth enhancement continues to be a cause for concern. Enterococci from 82 farms within a poultry production region on the eastern seaboard were isolated to establish a baseline of susceptibility profiles for a number of antimicrobials used in production as well as clinical environments. Of the 541 isolates recovered, Enterococcus faecalis (53%) and E. faecium (31%) were the predominant species, while multiresistant antimicrobial phenotypes were observed among all species. The prevalence of resistance among isolates of E. faecalis was comparatively higher among lincosamide, macrolide, and tetracycline antimicrobials, while isolates of E. faecium were observed to be more frequently resistant to fluoroquinolones and penicillins. Notably, 63% of the E. faecium isolates were resistant to the streptogramin quinupristin-dalfopristin, while high-level gentamicin resistance was observed only among the E. faecalis population, of which 7% of the isolates were resistant. The primary observations are that enterococci can be frequently isolated from the poultry production environment and can be multiresistant to antimicrobials used in human medicine. The high frequency with which resistant enterococci are isolated from this environment suggests that these organisms might be useful as sentinels to monitor the development of resistance resulting from the usage of antimicrobial agents in animal production. PMID:15466544

  2. Culture methods impact recovery of antibiotic-resistant Enterococci including Enterococcus cecorum from pre- and postharvest chicken.

    PubMed

    Suyemoto, M M; Barnes, H J; Borst, L B

    2017-03-01

    Pathogenic strains of Enterococcus cecorum (EC) expressing multidrug resistance have emerged. In National Antimicrobial Resistance Monitoring System (NARMS) data, EC is rarely recovered from chickens. Two NARMS methodologies (FDA and USDA) were compared with standard culture (SC) techniques for recovery of EC. NARMS methods failed to detect EC in 58 caecal samples, 20 chicken breast or six whole broiler samples. EC was recovered from 1 of 38 (2·6%) and 2 of 38 (5·2%) preharvest spinal lesions (USDA and FDA method, respectively). In contrast, using the SC method, EC was recovered from 44 of 53 (83%) caecal samples, all 38 (100%) spinal lesions, 14 of 20 (70%) chicken breast samples, and all three spinal lesions identified in whole carcasses. Compared with other Enterococcus spp., EC isolates had a higher prevalence of resistance to macrolides. The NARMS methods significantly affected recovery of enterococcal species other than EC. When the postharvest FDA method was applied to preharvest caecal samples, isolates of Enterococcus faecium were preferentially recovered. All 11 E. faecium isolates were multidrug resistant, including resistance to penicillin, daptomycin and linezolid. These findings confirm that current methodologies may not accurately identify the amount and range of antimicrobial resistance of enterococci from chicken sources.

  3. Comparison between automated system and PCR-based method for identification and antimicrobial susceptibility profile of clinical Enterococcus spp.

    PubMed

    Furlaneto-Maia, Luciana; Rocha, Kátia Real; Siqueira, Vera Lúcia Dias; Furlaneto, Márcia Cristina

    2014-01-01

    Enterococci are increasingly responsible for nosocomial infections worldwide. This study was undertaken to compare the identification and susceptibility profile using an automated MicrosScan system, PCR-based assay and disk diffusion assay of Enterococcus spp. We evaluated 30 clinical isolates of Enterococcus spp. Isolates were identified by MicrosScan system and PCR-based assay. The detection of antibiotic resistance genes (vancomycin, gentamicin, tetracycline and erythromycin) was also determined by PCR. Antimicrobial susceptibilities to vancomycin (30 µg), gentamicin (120 µg), tetracycline (30 µg) and erythromycin (15 µg) were tested by the automated system and disk diffusion method, and were interpreted according to the criteria recommended in CLSI guidelines. Concerning Enterococcus identification the general agreement between data obtained by the PCR method and by the automatic system was 90.0% (27/30). For all isolates of E. faecium and E. faecalis we observed 100% agreement. Resistance frequencies were higher in E. faecium than E. faecalis. The resistance rates obtained were higher for erythromycin (86.7%), vancomycin (80.0%), tetracycline (43.35) and gentamicin (33.3%). The correlation between disk diffusion and automation revealed an agreement for the majority of the antibiotics with category agreement rates of > 80%. The PCR-based assay, the van(A) gene was detected in 100% of vancomycin resistant enterococci. This assay is simple to conduct and reliable in the identification of clinically relevant enterococci. The data obtained reinforced the need for an improvement of the automated system to identify some enterococci.

  4. Detection of the esp gene in high-level gentamicin resistant Enterococcus faecalis strains from pet animals in Japan.

    PubMed

    Harada, Tetsuya; Tsuji, Noboru; Otsuki, Koichi; Murase, Toshiyuki

    2005-03-20

    We investigated the prevalence of the esp gene and the susceptibility to gentamicin in Enterococcus faecalis and E. faecium strains obtained from pet animals. Nine of 30 E. faecalis and 2 of 38 E. faecium strains from the pet animals had the esp gene. Three esp-positive E. faecalis strains, which were isolated from two dogs and a cat, showed gentamicin MICs of > or =256 microg/ml and harbored the high-level gentamicin resistance (HLGR) gene, aac(6')-Ie-aph(2'')-Ia. Of the nine esp-positive E. faecalis strains, five, including the three strains with the HLGR gene, were closely related by numerical analysis of PFGE patterns. Longitudinal investigation needs to elucidate whether the HLGR gene was incorporated into a subpopulation of the esp-positive E. faecalis.

  5. Native Microbial Colonization of Drosophila melanogaster and Its Use as a Model of Enterococcus faecalis Pathogenesis▿ †

    PubMed Central

    Cox, Christopher R.; Gilmore, Michael S.

    2007-01-01

    Enterococci are commensal organisms of the gastrointestinal (GI) tracts of a broad range of mammalian and insect hosts, but they are also leading causes of nosocomial infection. Little is known about the ecological role of enterococci in the GI tract consortia. To develop a tractable model for studying the roles of these organisms as commensals and pathogens, we characterized the Drosophila melanogaster microflora and examined the occurrence of enterococci in the gastrointestinal consortium of Drosophila. In a survey of laboratory-reared Drosophila and wild-captured flies, we found that Drosophila was naturally colonized by representatives of five bacterial phyla. Among these organisms were several species of enterococci, including Enterococcus faecalis, Enterococcus faecium, Enterococcus gallinaraum, and Enterococcus durans, as well as a previously detected but uncultured Enterococcus species. Drosophila could be cured of enterococcal carriage by antibiotic treatment and could be reassociated with laboratory strains. High-level colonization by a well-characterized strain expressing the enterococcal cytolysin was found to be detrimental to Drosophila compared to the effect of an isogenic, noncytolytic control. The anatomical distribution of enterococci in the Drosophila GI tract was determined by immunohistochemical staining of thin sections of naturally colonized and reassociated flies. PMID:17220307

  6. Bacteriocin Production in Vancomycin-Resistant and Vancomycin-Susceptible Enterococcus Isolates of Different Origins

    PubMed Central

    Del Campo, Rosa; Tenorio, Carmen; Jiménez-Díaz, Rufino; Rubio, Carmen; Gómez-Lus, Rafael; Baquero, Fernando; Torres, Carmen

    2001-01-01

    Bacteriocin production was determined for 218 Enterococcus isolates (Enterococcus faecalis [93] and E. faecium [125]) obtained from different origins (human clinical samples [87], human fecal samples [78], sewage [28], and chicken samples [25]) and showing different vancomycin susceptibility patterns (vancomycin resistant, all of them vanA positive [56], and vancomycin susceptible [162]). All enterococcal isolates were randomly selected except for the vancomycin-resistant ones. A total of 33 isolates of eight different bacterial genera were used as indicators for bacteriocin production. Forty-seven percent of the analyzed enterococcal isolates were bacteriocin producers (80.6% of E. faecalis and 21.6% of E. faecium isolates). The percentage of bacteriocin producers was higher among human clinical isolates (63.2%, 81.8% of vancomycin-resistant isolates and 60.5% of vancomycin-susceptible ones) than among isolates from the other origins (28 to 39.3%). Only one out of the 15 vancomycin-resistant isolates from human fecal samples was a bacteriocin producer, while 44.4% of fecal vancomycin-susceptible isolates were. The bacteriocin produced by the vanA-containing E. faecium strain RC714, named bacteriocin RC714, was further characterized. This bacteriocin activity was cotransferred together with the vanA genetic determinant to E. faecalis strain JH2-2. Bacteriocin RC714 was purified to homogeneity and its primary structure was determined by amino acid sequencing, showing an identity of 88% and a similarity of 92% with the previously described bacteriocin 31 from E. faecalis YI717. The presence of five different amino acids in bacteriocin RC714 suggest that this could be a new bacteriocin. The results obtained suggest that the epidemiology of vancomycin resistance may be influenced by different factors, including bacteriocin production. PMID:11181378

  7. Enterococcus and Streptococcus spp. associated with chronic and self-medicated urinary tract infections in Vietnam

    PubMed Central

    2012-01-01

    Background Urinary tract infections (UTI) are one of the most common infections among women worldwide. E. coli often causes more than 75% of acute uncomplicated UTI, however, little is known about how recurrent UTIs and indiscriminate use of antimicrobials affect the aetiology of UTIs. This study aimed to establish the aetiology of UTI in a population of recurrent and self-medicated patients referred from pharmacies to a hospital in Hanoi, Vietnam and to describe genotypes and antimicrobial susceptibility of the associated bacterial pathogens. The aetiology of bacterial pathogens associated with UTI (defined as ≥ 104 CFU/ml urine) was established by phenotypic and molecular methods. Enterococcus faecalis isolates were typed by Multi Locus Sequence Typing (MLST), Pulsed-Field Gel Electrophoresis (PFGE) and antimicrobial susceptibility testing. Methods Urine samples from 276 patients suffering symptoms of urinary tract infection were collected and cultured on Flexicult agar® allowing for detection of the most common urine pathogens. Patients were interviewed about underlying diseases, duration of symptoms, earlier episodes of UTI, number of episodes diagnosed by doctors and treatment in relation to UTI. All tentative E. faecalis and E. faecium isolates were identified to species level by PCR, 16S rRNA and partial sequencing of the groEL gene. E. faecalis isolates were further characterized by Multi Locus Sequence Typing and antimicrobial susceptibility testing. Results Mean age of 49 patients was 48 yrs (range was 11–86 yrs) and included 94% women. On average, patients reported to have suffered from UTI for 348 days (range 3 days-10 years, and experienced 2.7 UTIs during the previous year). Cephalosporins were reported the second drug of choice in treatment of UTI at the hospital. E. faecalis (55.1%), E. coli (12.2%) and Streptococcus gallolyticus subsp. pasteurianus (8.2%) were main bacterial pathogens. MIC testing of E. faecalis showed susceptibility to

  8. Use of synthetic genes for cloning, production and functional expression of the bacteriocins enterocin A and bacteriocin E 50-52 by Pichia pastoris and Kluyveromyces lactis.

    PubMed

    Jiménez, Juan J; Borrero, Juan; Gútiez, Loreto; Arbulu, Sara; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E

    2014-06-01

    The use of synthetic genes may constitute a successful approach for the heterologous production and functional expression of bacterial antimicrobial peptides (bacteriocins) by recombinant yeasts. In this work, synthetic genes with adapted codon usage designed from the mature amino acid sequence of the bacteriocin enterocin A (EntA), produced by Enterococcus faecium T136, and the mature bacteriocin E 50-52 (BacE50-52), produced by E. faecium NRRL B-32746, were synthesized. The synthetic entA and bacE50-52 were cloned into the protein expression vectors pPICZαA and pKLAC2 for transformation of derived vectors into Pichia pastoris X-33 and Kluyveromyces lactis GG799, respectively. The recombinant vectors were linearized and transformed into competent cells selecting for P. pastoris X-33EAS (entA), P. pastoris X-33BE50-52S (bacE50-52), K. lactis GG799EAS (entA), and K. lactis GG799BE50-52S (bacE50-52). P. pastoris X-33EAS and K. lactis GG799EAS, but not P. pastoris X-33BE50-52S and K. lactis GG799BE50-52S, showed antimicrobial activity in their supernatants. However, purification of the supernatants of the producer yeasts permitted recovery of the bacteriocins EntA and BacE50-52. Both purified bacteriocins were active against Gram-positive bacteria such as Listeria monocytogenes but not against Gram-negative bacteria, including Campylobacter jejuni.

  9. Retrospective analysis of Salmonella, Campylobacter, Escherichia coli, and Enterococcus in animal feed ingredients.

    PubMed

    Ge, Beilei; LaFon, Patricia C; Carter, Peggy J; McDermott, Shawn D; Abbott, Jason; Glenn, Althea; Ayers, Sherry L; Friedman, Sharon L; Paige, Joseph C; Wagner, David D; Zhao, Shaohua; McDermott, Patrick F; Rasmussen, Mark A

    2013-08-01

    The presence and antimicrobial susceptibility of foodborne pathogens and indicator organisms in animal feed are not well understood. In this study, a total of 201 feed ingredient samples (animal byproducts, n=122; plant byproducts, n=79) were collected in 2002 and 2003 from representative rendering plants and the oilseed (or cereal grain) industry across the United States. The occurrence and antimicrobial susceptibility of four bacterial genera (Salmonella, Campylobacter, Escherichia coli, and Enterococcus) were determined. Salmonella isolates were further characterized by serotyping and pulsed-field gel electrophoresis (PFGE). None of the samples yielded Campylobacter or E. coli O157:H7, whereas Salmonella, generic E. coli, and Enterococcus were present in 22.9%, 39.3%, and 86.6% of samples, respectively. A large percentage (47.8%) of Salmonella-positive samples harbored two serovars, and the vast majority (88.4%) of Enterococcus isolates were E. faecium. Animal byproducts had a significantly higher Salmonella contamination rate (34.4%) than plant byproducts (5.1%) (p<0.05). Among 74 Salmonella isolates recovered, 27 serovars and 55 PFGE patterns were identified; all were pan-susceptible to 17 antimicrobials tested. E. coli isolates (n=131) demonstrated similar susceptibility to these antimicrobials except for tetracycline (15.3% resistance), sulfamethoxazole (7.6%), streptomycin (4.6%), ampicillin (3.8%), and nalidixic acid (1.5%). Enterococcus isolates (n=362) were also resistant to five of 17 antimicrobials tested, ranging from 1.1% to penicillin to 14.6% to tetracycline. Resistance rates were generally higher among isolates recovered from animal byproducts. Taken together, our findings suggest that diverse populations of Salmonella, E. coli, and Enterococcus are commonly present in animal feed ingredients, but antimicrobial resistance is not common. Future large-scale studies to monitor these pathogenic and indicator organisms in feed commodities is warranted.

  10. Association between Enterococcus bacteraemia and death in neutropenic patients with haematological malignancies.

    PubMed

    Todeschini, Giuseppe; Tecchio, Cristina; Borghero, Carlo; D'Emilio, Anna; Pegoraro, Enrico; de Lalla, Fausto; Benedetti, Paolo; Spolaore, Paolo; Pellizzer, Giampietro

    2006-10-01

    Fatality rates and prognostic factors for mortality due to Enterococcus spp. bacteraemia have not yet been fully defined in the setting of neutropenic patients affected with haematological malignancies. We have performed a retrospective, multi-centre cohort study on 98 episodes of Enterococcus bacteraemia occurring in patients hospitalised from January 1984 to December 2001 at the oncohaematology units in two tertiary-care hospitals (Verona Hospital and Vicenza Hospital, in north-east Italy). E. faecalis was isolated in 52 cases (53%), E. faecium in 39 (39.8%), E. avium in four, E. durans in one, and untyped Enterococcus spp. in two other cases; vancomycin resistance was detected in 15 (15.3%) isolates. A global mortality rate of 41.8% (41/98 cases) was revealed; Enterococcus spp. bacteraemia was associated with a fatal outcome in 29/98 cases (29.5%). The following variables were independently associated with an increased risk of death by multivariate analysis of survival: age > or =50 years (OR 3.74; 95% CI 1.35-10.32), pneumonia (OR 4.70; 95% CI 1.67-13.20), and shock (OR 13.7; 95% CI 1.23-152.43), while the initial phase of haematological disease (responsive to chemotherapy) appeared to be protective (OR 0.23; 95% CI 0.008-0.64, P level 0.005); however, pneumonia alone (OR 7.2, 95% CI 2.52-20.88) was independently associated with fatal outcome by multivariate analysis for death related to enterococcal bacteraemia. In our experience, the poor outcome proper to enterococcal bacteraemia appears to be directly related to underlying disease, patient's age, presence of pneumonia and shock; in contrast, severe neutropaenia, antibiotic resistance, and species of Enterococcus do not appear to affect the fatality rate significantly.

  11. Identification, antimicrobial resistance and genotypic characterization of Enterococcus spp. isolated in Porto Alegre, Brazil

    PubMed Central

    Bender, Eduardo André; de Freitas, Ana Lúcia Peixoto; Reiter, Keli Cristine; Lutz, Larissa; Barth, Afonso Luís

    2009-01-01

    In the past two decades the members of the genus Enterococcus have emerged as important nosocomial pathogens worldwide. In the present study, we evaluated the antimicrobial resistance and genotypic characteristics of 203 Enterococcus spp. recovered from different clinical sources from two hospitals in Porto Alegre, Rio Grande do Sul, Brazil. The species were identified by conventional biochemical tests and by an automated system. The genetic diversity of E. faecalis presenting high-level aminoglycoside resistance (HLAR) was assessed by pulsed-field gel electrophoresis of chromosomal DNA after SmaI digestion. The E. faecalis was the most frequent specie (93.6%), followed by E. faecium (4.4%). The antimicrobial resistance profile was: 2.5% to ampicillin, 0.5% to vancomycin, 0.5% teicoplanin, 33% to chloramphenicol, 2% to nitrofurantoin, 66.1% to erythromycin, 66.5% to tetracycline, 24.6% to rifampicin, 30% to ciprofloxacin and 87.2% to quinupristin-dalfopristin. A total of 10.3% of the isolates proved to be HLAR to both gentamicin and streptomycin (HLR-ST/GE), with 23.6% resistant only to gentamicin (HLR-GE) and 37.4% only to streptomycin (HLR-ST). One predominant clonal group was found among E. faecalis HLR-GE/ST. The prevalence of resistance among beta-lactam antibiotics and glycopeptides was very low. However, in this study there was an increased number of HLR Enterococcus which may be spreading intra and inter-hospital. PMID:24031416

  12. Genotypic and phenotypic heterogeneity in Enterococcus isolates from Batzos, a raw goat milk cheese.

    PubMed

    Psoni, L; Kotzamanides, C; Andrighetto, C; Lombardi, A; Tzanetakis, N; Litopoulou-Tzanetaki, E

    2006-05-25

    This study investigated the genotypic and phenotypic diversity in 34 isolates of enterococci obtained during ripening of Batzos cheese from raw goat milk and characterized phenotypically as Enterococcus durans. RAPD-PCR, plasmid profiling and PFGE were used to study the genetic variability and distinguish closely related isolates. Species recognition by means of RAPD-PCR was in agreement with the phenotypic identification for 29 strains. One strain was characterized as Lactococcus lactis subsp. lactis by RAPD-PCR and four strains were grouped with the Enterococcus faecium reference strain. All strains were vancomycin sensitive, while 10 strains showed beta-haemolytic reaction on human blood and the majority of them (88.9%) showed decarboxylase activity on tyramine. All strains exhibited antagonistic activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli and Listeria monocytogenes and the majority inhibited Enterococcus faecalis. Isolates displayed weak acidifying ability and low proteolytic activities when grown in milk for 24h. However, their caseinolytic activity after growth in milk for seven days was significant with preference for alphas-casein degradation.

  13. Identification, antimicrobial susceptibility, and virulence factors of Enterococcus spp. strains isolated from Camels in Canary Islands, Spain.

    PubMed

    Tejedor Junco, María Teresa; Gonzalez-Martin, Margarita; Rodriguez Gonzalez, Noe Francisco; Gutierrez, Carlos

    2015-01-01

    This study investigated the presence of Enterococcus spp. strains in camel faeces, their virulence factors, and resistance to the antibiotics commonly used as therapy of enterococcal infections. One hundred and seventy three Enterococcus strains were isolated and identified to species level using polymerase chain reaction (PCR). Susceptibility to 11 antimicrobials was determined by disk diffusion method. Minimal Inhibitory Concentrations (MIC) of penicillin, ampicillin, vancomycin, teicoplanin, gentamicin, and streptomycin were all determined. Genes encoding resistance to vancomycin, tetracycline, and erythromycin as well as genes encoding some virulence factors were identified by PCR. Enterococcus hirae (54.3%) and Enterococcus faecium (25.4%) were the species most frequently isolated. None of the strains were resistant to vancomycin, teicoplanin, ampicillin or showed high level aminoglycoside resistance (HLAR). Strains resistant to rifampicin (42.42%) were those most commonly found followed those resistant to trimethoprim - sulfamethoxazole (33.33%). The genes tetM, tetL, vanC1, and vanC2-C3 were detected in some strains. Virulence genes were not detected. Monitoring the presence of resistant strains of faecal enterococci in animal used with recreational purposes is important to prevent transmission of those strains to humans and to detect resistance or virulence genes that could be transferred to other clinically important bacteria.

  14. Diurnal variation in Enterococcus species composition in polluted ocean water and a potential role for the enterococcal carotenoid in protection against photoinactivation.

    PubMed

    Maraccini, Peter A; Ferguson, Donna M; Boehm, Alexandria B

    2012-01-01

    Enterococcus species composition was determined each hour for 72 h at a polluted marine beach in Avalon, Santa Catalina Island, CA. Species composition during the day was significantly different from that at night, based on an analysis of similarity. Enterococcus faecium and E. faecalis were more prevalent at night than during the day, while E. hirae and other Enterococcus species were more prevalent during the day than the night. Enterococcus spp. containing a yellow pigment were more common during the day than the night, suggesting that the pigmented phenotype may offer a competitive advantage under sunlit conditions. A laboratory microcosm experiment established that the pigmented E. casseliflavus isolate and a pigmented E. faecalis isolate recovered from the field site decay slower than a nonpigmented E. faecalis isolate in a solar simulator in simulated, clear seawater. This further supports the idea that the yellow carotenoid pigment in Enterococcus provides protection under sunlit conditions. The findings are in accordance with previous work with other carotenoid-containing nonphotosynthetic and photosynthetic bacteria that suggests that the carotenoid is able to quench reactive oxygen species capable of causing photoinactivation and photostress. The results suggest that using enterococcal species composition as a microbial source tracking tool may be hindered by the differential environmental persistence of pigmented and nonpigmented enterococci.

  15. Dissemination of antibiotic resistant Enterococcus spp. and Escherichia coli from wild birds of Azores Archipelago.

    PubMed

    Santos, Tiago; Silva, Nuno; Igrejas, Gilberto; Rodrigues, Pedro; Micael, Joana; Rodrigues, Tiago; Resendes, Roberto; Gonçalves, Alexandre; Marinho, Catarina; Gonçalves, David; Cunha, Regina; Poeta, Patrícia

    2013-12-01

    Antibiotic-resistant is profoundly important to human and animal health, but the environmental reservoirs of resistance determinants are poorly understood, in particular in wild environments in remote Archipelagos. Moreover, the prevalence of antibiotic-resistant bacteria in wild bird populations is rather unknown. In the present study, we used the Azores Islands as a model study for antimicrobial resistance in a remote Archipelago, and examined the antibiotic resistance profile in enterococci and Escherichia coli recovered from faecal samples of wild birds collected in this Archipelago. A total of 138 enterococci and 115 E. coli isolates were analyzed for resistance to antimicrobial agents. Of the enterococcal isolates, Enterococcus faecalis was the most prevalent detected species (59 isolates), followed by Enterococcus faecium (40 isolates), Enterococcus durans (27 isolates) and Enterococcus hirae (12 isolates). The enterococci strains showed high percentages of resistance to tetracycline (32.6%), to ciprofloxacin (19.6%) and to erythromycin (11.6%). Lower level of resistance (<10%) was detected for ampicillin, chloramphenicol and teicoplanin. One vancomycin-resistant E. faecalis isolate was detected and harbored the vanA resistant gene. Resistance genes detected included tet(M) and/or tet(L), ermB in all tetracycline and erythromycin-resistant isolates. Resistance in E. coli isolates was detected for ampicillin, tetracycline, sulfamethoxazole/trimethoprim, streptomycin, and tobramycin. The blaTEM, aadA, aadA5, strA, strB, tet(A) and/or tet(B), and the intI genes were found in all ampicillin, streptomycin, tetracycline, and sulfamethoxazole/trimethoprim-resistant isolates respectively. The data shown in this study are essential to improve knowledge about the dissemination of resistant strains through wild birds from remote archipelagos such as the Azores Archipelago and the possible implications involved in transferring these resistances either to other animals

  16. Vancomycin resistant Enterococcus spp. from crows and their environment in metropolitan Washington State, USA: Is there a correlation between VRE positive crows and the environment?

    PubMed

    Roberts, Marilyn C; No, David B; Marzluff, John M; Delap, Jack H; Turner, Robert

    2016-10-15

    Vancomycin-resistant enterococci [VRE] have been isolated from municipal, hospital and agricultural wastewater, recreational beaches, wild animals, birds and food animals around the world. In this study, American crows (Corvus brachyrhynchos) from sewage treatment plants (WWTP), dairy farms, and a large roost in a restored wetland with corresponding environmental samples were cultured for VRE. A total of 245 samples [156 crows, 89 environmental] were collected and screened for acquired vanA, vanB and/or intrinsic vanC1 genes. Samples were enriched overnight in BHI supplemented with 20μg/mL aztreonam, 4μg/mL vancomycin and plated on m-Enterococcus agar media supplemented with 6μg/mL vancomycin. Selected colonies were grown on BHI media supplemented with 18μg/mL vancomycin. Of these, 24.5% of the crow and 55% the environmental/cow samples were VRE positive as defined by Enterococcus spp. able to grow on media supplemented with 18μg/mL vancomycin. A total of 122 VRE isolates, 43 crow and 79 environmental isolates were screened, identified to species level using 16S sequencing and further characterized. Four vanA E. faecium and multiple vanC1 E. gallinarum were identified from crows isolated from three sites. E. faecium vanA and E. gallinarum vanC1 along with other Enterococcus spp. carrying vanA, vanB, vanC1 were isolated from three environments. All enterococci were multidrug resistant. Crows were more likely to carry vanA E. faecium than either the cow feces or wetland waters/soils. Comparing E. gallinarum vanC1 from crows and their environment would be useful in determining whether crows share VRE strains with their environment.

  17. Development of quantitative PCR assays targeting the 16S rRNA genes of Enterococcus spp. and their application to the identification of enterococcus species in environmental samples.

    PubMed

    Ryu, Hodon; Henson, Michael; Elk, Michael; Toledo-Hernandez, Carlos; Griffith, John; Blackwood, Denene; Noble, Rachel; Gourmelon, Michèle; Glassmeyer, Susan; Santo Domingo, Jorge W

    2013-01-01

    The detection of environmental enterococci has been determined primarily by using culture-based techniques that might exclude some enterococcal species as well as those that are nonculturable. To address this, the relative abundances of enterococci were examined by challenging fecal and water samples against a currently available genus-specific assay (Entero1). To determine the diversity of enterococcal species, 16S rRNA gene-based group-specific quantitative PCR (qPCR) assays were developed and evaluated against eight of the most common environmental enterococcal species. Partial 16S rRNA gene sequences of 439 presumptive environmental enterococcal strains were analyzed to study further the diversity of enterococci and to confirm the specificities of group-specific assays. The group-specific qPCR assays showed relatively high amplification rates with targeted species (>98%), although some assays cross-amplified with nontargeted species (1.3 to 6.5%). The results with the group-specific assays also showed that different enterococcal species co-occurred in most fecal samples. The most abundant enterococci in water and fecal samples were Enterococcus faecalis and Enterococcus faecium, although we identified more water isolates as Enterococcus casseliflavus than as any of the other species. The prevalence of the Entero1 marker was in agreement with the combined number of positive signals determined by the group-specific assays in most fecal samples, except in gull feces. On the other hand, the number of group-specific assay signals was lower in all water samples tested, suggesting that other enterococcal species are present in these samples. While the results highlight the value of genus- and group-specific assays for detecting the major enterococcal groups in environmental water samples, additional studies are needed to determine further the diversity, distributions, and relative abundances of all enterococcal species found in water.

  18. Superbugs in the coming new decade; multidrug resistance and prospects for treatment of Staphylococcus aureus, Enterococcus spp. and Pseudomonas aeruginosa in 2010.

    PubMed

    Nordmann, Patrice; Naas, Thierry; Fortineau, Nicolas; Poirel, Laurent

    2007-10-01

    New resistance problems have emerged recently among hospital and community-acquired pathogens such as in Staphylococcus aureus, Enterococcus faecium and Pseudomonas aeruginosa. Hospital-acquired and now community-acquired methicillin-resistant S. aureus are emerging worldwide whereas vancomycin-resistant S. aureus remain extremely rare. Hospital-acquired outbreaks of vancomycin-resistant enterococci and multidrug resistant Pseudomonas aeruginosa infections are increasingly reported worldwide. Whereas novel molecules are being developed for treating Gram-positive infections, difficult to non possible-to-treat pandrug-resistant P. aeruginosa infections may become a therapeutic challenge soon.

  19. Genetic characterization of antibiotic resistance and virulence factors in Enterococcus spp. from Japanese retail ready-to-eat raw fish.

    PubMed

    Hammad, Ahmed M; Shimamoto, Toshi; Shimamoto, Tadashi

    2014-04-01

    Little information is available on the diversity and distribution of resistance and virulence factors in enterococci isolated from retail fish. In this study, 200 samples of retail ready-to-eat raw fish (sashimi) collected from the Japanese prefecture of Hiroshima were analyzed for incidence of Enterococcus spp. We recovered 96 enterococcal isolates from 90 (45%, 90/200) samples. Fifty-six strains were identified at the species level: E. faecalis (n = 31), E. faecium (n = 7), E. casseliflavus (n = 7), E. gallinarum (n = 3), E. phoeniculicola (n = 4), E. raffinosus (n = 2), E. saccharolyticus (n = 1), and E. gilvus (n = 1). Twenty-five (26%, 25/96) strains carried antibiotic resistance genes. These included the tet(M), tet(L), tet(K), erm(B), msr(A/B), aph(3'), and blaZ genes, which were detected in 12.5%, 9.3%, 2%, 14.5%, 1%, 1%, and 2% of isolates, respectively. The virulence genes gelE and asa1 were detected in 31 and 24 E. faecalis strains, respectively. Both genes were detected in one E. faecium strain. In conclusion, this is the first study to underscore the importance of sashimi as not only a reservoir of Enterococcus spp. carrying resistance and virulence genes, but also a reservoir for unusual Enterococcus spp.

  20. Complete Genome Sequences of Enterococcus rotai LMG 26678T and Enterococcus silesiacus LMG 23085T

    PubMed Central

    Lauer, Ana C.; Humrighouse, Ben W.; Loparev, Vladimir; Shewmaker, Patricia L.; McQuiston, John R.; McLaughlin, Richard W.

    2016-01-01

    The inclusion of molecular methods in the characterization of the novel species Enterococcus horridus necessitated the sequencing and assembly of the genomes of the closely related Enterococcus rotai and Enterococcus silesiacus. Sequencing using Illumina technology in combination with optical mapping led to the generation of closed genomes for both isolates. PMID:27979941

  1. High Frequency of Vancomycin-Resistant Enterococcus Faecalis in an Iranian Referral Children Medical Hospital

    PubMed Central

    POURAKBARI, Babak; AGHDAM, Mojtaba Kamali; MAHMOUDI, Shima; ASHTIANI, Mohammad Taghi Haghi; SABOUNI, Farah; MOVAHEDI, Zahra; ALYARI, Amir Esmael; SADEGHI, Reihane Hosseinpour; MAMISHI, Setareh

    2012-01-01

    ABSTRACT Background: Enterococci have emerged in recent years as important nosocomial pathogens. Although most enterococcal human infections are caused by Enterococcus faecalis, studies on vancomycin resistance are usually limited to Enterococcus faecium isolates and a little is known about E. faecalis. Therefore we undertook this study to obtain information about the prevalence of vancomycin -resistant E. faecalis (VREF) and genes responsible for resistance. Material and methods: Ninety-one E. faecalis isolates of different patients admitted at Children's Medical Center from August 2009 to June 2010 were included in this cross-sectional study. Antimicrobial testing was performed by Kirby-Bauer disk diffusion method according to Clinical Laboratories Standards Institute (CLSI). Results: Among all isolates, 15 (16%) were identified as VR E. faecalis. PCR analysis revealed that all VREF isolates were positive for the vanA gene. Conclusion: The present study reports the highest range of VREF in Iran. The increased frequency of VREF, as seen with rapid rise in the number of VanA isolates should be considered in infection control practices. PMID:23400108

  2. 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.

  3. Are Enterococcus populations present during malolactic fermentation of red wine safe?

    PubMed

    Pérez-Martín, Fátima; Seseña, Susana; Izquierdo, Pedro Miguel; Palop, María Llanos

    2014-09-01

    The aim of this study was the genetic characterisation and safety evaluation of 129 Enterococcus isolates obtained from wine undergoing malolactic fermentation. Genetic characterisation by randomly amplified polymorphic DNA-PCR displayed 23 genotypes. 25 isolates representative of all genotypes were identified as Enterococcus faecium by species-specific PCR and assayed for antibiotic resistance, presence of virulence genes and aminobiogenic capacity, both in decarboxylase medium and wine. The aminobiogenic capacity in wine was analysed in presence (assay 1) and absence (assay 2) of Oenococcus oeni CECT 7621. Resistance to tetracycline, cotrimoxazol, vancomycin and teicoplanin was exhibited by 96% of the strains, but none of them harboured the assayed virulence genes. All of the strains harboured the tyrosine decarboxylase (tdc) gene, while 44% were positive for tyramine in decarboxylase medium. Only five out of 25 strains survived in wine after seven days of incubation, and when concentrations of biogenic amines in wines were determined by HPLC, only those wines in which the five surviving strains occurred contained biogenic amines. Histamine, putrescine and cadaverine were detected in wines from both assays, although concentrations were higher in assay 2. Tyramine and phenylethylamine were detected only in absence of O. oeni. This research contributes for the knowledge of safety aspects of enterococci related to winemaking.

  4. Comparative analysis on antibiotic resistance characteristics of Listeria spp. and Enterococcus spp. isolated from laying hens and eggs in conventional and organic keeping systems in Bavaria, Germany.

    PubMed

    Schwaiger, K; Schmied, E-M V; Bauer, J

    2010-05-01

    By investigating the prevalence and antimicrobial resistance characteristics of Gram-positive bacteria from organic and conventional keeping systems of laying hens, it was to be determined to what extent these properties are influenced by the different systems. For this purpose, a total of 799 cloacal swabs and 800 egg samples were examined. Prevalences for all selected bacteria from cloacal swabs were much the same for both organic and caged birds: Listeria spp.1.3%[org] versus 1.6%[con]; Enterococcus spp. 95.5%[org] versus 97.5%[con]. Egg contents and eggshells were generally contaminated to a lesser extent, primarily with Enterococcus spp. Listeria isolates were susceptible to almost all tested antibiotics, only three Listeria innocua from conventional keepings were resistant to clindamycin; one isolate additionally to imipenem. High percentages of Enterococcus faecalis were resistant to doxycycline and macrolides. Enterococcus faecium proved to have high resistance rates to clindamycin, fosfomycin and erythromycin; 9.1% were even resistant to the reserve antibiotic synercid. Further, Enterococcus spp. showed higher resistance rates to doxycycline, erythromycin, fosfomycin and rifampicin. No glycopeptide resistant enterococci were detected. A correlation between keeping system and resistance/susceptibility rates could be demonstrated. In detail, E. faecalis from organic laying hen husbandries showed significant lower resistance prevalences to tylosin, streptomycin and doxycycline; susceptibility rates were higher for enrofloxacin and ciprofloxacin. Rifampicin and imipenem were more effective in isolates from conventional keepings (P < 0.05). The amounts of resistant isolates of the Enterococcus raffinosus from organic farms were significantly lower, the amounts of sensitive isolates were significantly higher than from conventional farms concerning eight antibiotics (P < 0.05). When comparing the susceptibility/resistance rates, as well as the mean minimum

  5. Diversity and Evolution of the Tn5801-tet(M)-Like Integrative and Conjugative Elements among Enterococcus, Streptococcus, and Staphylococcus.

    PubMed

    León-Sampedro, Ricardo; Novais, Carla; Peixe, Luísa; Baquero, Fernando; Coque, Teresa M

    2016-01-04

    This work describes the diversity and evolution of Tn5801 among enterococci, staphylococci, and streptococci based on analysis of the 5,073 genomes of these bacterial groups available in gene databases. We also examined 610 isolates of Enterococcus (from 10 countries, 1987 to 2010) for the presence of this and other known CTn-tet(M) elements due to the scarcity of data about Tn5801 among enterococci. Genome location (by ICeu-I-pulsed-field gel electrophoresis [PFGE] hybridization/integration site identification), conjugation and fitness (by standard methods), Tn5801 characterization (by long-PCR mapping/sequencing), and clonality (by PFGE/multilocus sequence typing [MLST]) were studied. Twenty-three Tn5801 variants (17 unpublished) clustered in two groups, designated "A" (25 kb; n = 14; predominant in Staphylococcus aureus) and "B" (20 kb; n = 9; predominant in Streptococcus agalactiae). The percent GC content of the common backbone suggests a streptococcal origin of Tn5801 group B, with further acquisition of a 5-kb fragment that resulted in group A. Deep sequence analysis allowed identification of variants associated with clonal lineages of S. aureus (clonal complex 8 [CC8], sequence type 239 [ST239]), S. agalactiae (CC17), Enterococcus faecium (ST17/ST18), or Enterococcus faecalis (ST8), local variants, or variants located in different species and geographical areas. All Tn5801 elements were chromosomally located upstream of the guaA gene, which serves as an integration hot spot. Transferability was demonstrated only for Tn5801 type B among E. faecalis clonal backgrounds, which eventually harbored another Tn5801 copy. The study documents early acquisition of Tn5801 by Enterococcus, Staphylococcus, and Streptococcus. Clonal waves of these pathogens seem to have contributed to the geographical spread and local evolution of the transposon. Horizontal transfer, also demonstrated, could explain the variability observed, with the isolates often containing sequences of

  6. Diversity and Evolution of the Tn5801-tet(M)-Like Integrative and Conjugative Elements among Enterococcus, Streptococcus, and Staphylococcus

    PubMed Central

    León-Sampedro, Ricardo; Novais, Carla; Peixe, Luísa; Baquero, Fernando

    2016-01-01

    This work describes the diversity and evolution of Tn5801 among enterococci, staphylococci, and streptococci based on analysis of the 5,073 genomes of these bacterial groups available in gene databases. We also examined 610 isolates of Enterococcus (from 10 countries, 1987 to 2010) for the presence of this and other known CTn-tet(M) elements due to the scarcity of data about Tn5801 among enterococci. Genome location (by ICeu-I–pulsed-field gel electrophoresis [PFGE] hybridization/integration site identification), conjugation and fitness (by standard methods), Tn5801 characterization (by long-PCR mapping/sequencing), and clonality (by PFGE/multilocus sequence typing [MLST]) were studied. Twenty-three Tn5801 variants (17 unpublished) clustered in two groups, designated “A” (25 kb; n = 14; predominant in Staphylococcus aureus) and “B” (20 kb; n = 9; predominant in Streptococcus agalactiae). The percent GC content of the common backbone suggests a streptococcal origin of Tn5801 group B, with further acquisition of a 5-kb fragment that resulted in group A. Deep sequence analysis allowed identification of variants associated with clonal lineages of S. aureus (clonal complex 8 [CC8], sequence type 239 [ST239]), S. agalactiae (CC17), Enterococcus faecium (ST17/ST18), or Enterococcus faecalis (ST8), local variants, or variants located in different species and geographical areas. All Tn5801 elements were chromosomally located upstream of the guaA gene, which serves as an integration hot spot. Transferability was demonstrated only for Tn5801 type B among E. faecalis clonal backgrounds, which eventually harbored another Tn5801 copy. The study documents early acquisition of Tn5801 by Enterococcus, Staphylococcus, and Streptococcus. Clonal waves of these pathogens seem to have contributed to the geographical spread and local evolution of the transposon. Horizontal transfer, also demonstrated, could explain the variability observed, with the isolates often containing

  7. Why Clone?

    MedlinePlus

    ... for tens of millions of years to clone dinosaurs. They run into trouble, however, when they realize ... and fiercer than expected. Could we really clone dinosaurs? In theory? Yes. You would need: A well- ...

  8. Effect of oil and dry roasting of peanuts at various temperatures and times on survival of Salmonella and Enterococcus faecium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A number of outbreaks of salmonellosis since 2006 associated with the consumption of Salmonella-contaminated peanut butter have increased concerns about this food and the associated processing methods. Laboratory studies were conducted to determine the level of Salmonella reduction associated with o...

  9. BACTERIOCIN E1073 PRODUCED BY ENTEROCOCCUS FAECIUM LWP1073 IS EFFECTIVE FOR TREATING COMMENSAL CLOSTRIDIUM PERFRINGENS INFECTION IN BROILERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enterotoxin-producing Clostridium perfringens type A bacteria occupy a significant place in the etiological structure of food-borne infections in humans. One potential approach to minimize infections associated with food-borne pathogens is to control the carriage of C. perfringens in broilers. For ...

  10. Increasing Prevalence of Aminoglycoside-Resistant Enterococcus faecalis Isolates Due to the aac(6’)-aph(2”) Gene: A Therapeutic Problem in Kermanshah, Iran

    PubMed Central

    Khani, Mitra; Fatollahzade, Mahdie; Pajavand, Hamid; Bakhtiari, Somaye; Abiri, Ramin

    2016-01-01

    Background: Enterococci are important pathogens in nosocomial infections. Various types of antibiotics, such as aminoglycosides, are used for treatment of these infections. Enterococci can acquire resistant traits, which can lead to therapeutic problems with aminoglycosides. Objectives: This study was designed to identify the prevalence of, and to compare, the aac(6’)-aph(2”) and aph(3)-IIIa genes and their antimicrobial resistance patterns among Enterococcus faecalis and E. faecium isolates from patients at Imam Reza hospital in Kermanshah in 2011 - 2012. Patients and Methods: One hundred thirty-eight clinical specimens collected from different wards of Imam Reza hospital were identified to the species level by biochemical tests. Antimicrobial susceptibility tests against kanamycin, teicoplanin, streptomycin, imipenem, ciprofloxacin, and ampicillin were performed by the disk diffusion method. The minimum inhibitory concentrations of gentamicin, streptomycin, kanamycin, and amikacin were evaluated with the microbroth dilution method. The aminoglycoside resistance genes aac(6’)-aph(2”) and aph(3”)-IIIa were analyzed with multiplex PCR. Results: The prevalence of isolates was 33 (24.1%) for E. faecium and 63 (46%) for E. faecalis. Eighty-nine percent of the isolates were high-level gentamicin resistant (HLGR), and 32.8% of E. faecium isolates and 67.2% of E. faecalis isolates carried aac(6’)-aph(2”). The prevalence of aph(3”)-IIIa among the E. faecalis and E. faecium isolates was 22.7% and 77.3%, respectively. Conclusions: Remarkably increased incidence of aac(6’)-aph(2”) among HLGR isolates explains the relationship between this gene and the high level of resistance to aminoglycosides. As the resistant gene among enterococci can be transferred, the use of new-generation antibiotics is necessary. PMID:27217920

  11. [Cloning - controversies].

    PubMed

    Twardowski, T; Michalska, A

    2001-01-01

    Cloning of the human being is not only highly controversial; in the opinion of the authors it is impossible - we are not able to reproduce human behaviour and character traits. Reproduction through cloning is limited to personal genome resources. The more important is protection of genomic characteristics as private property and taking advantage of cloning for production of the human organs directly or through xenotransplants. In this paper we present the legislation related to cloning in Poland, in the European Union and other countries. We also indicate who and why is interested in cloning.

  12. Chromosome and cell wall segregation in Streptococcus faecium ATCC 9790

    SciTech Connect

    Higgins, M.L.; Glaser, D.; Dicker, D.T.; Zito, E.T.

    1989-01-01

    Segregation was studied by measuring the positions of autoradiographic grain clusters in chains formed from single cells containing on average less than one radiolabeled chromosome strand. The degree to which chromosomal and cell wall material cosegregated was quantified by using the methods of S. Cooper and M. Weinberger, dividing the number of chains labeled at the middle. This analysis indicated that in contrast to chromosomal segregation in Escherichia coli and, in some studies, to that in gram-positive rods, chromosomal segregation in Streptococcus faecium was slightly nonrandom and did not vary with growth rate. Results were not significantly affected by strand exchange. In contrast, labeled cell wall segregated predominantly nonrandomly.

  13. Enterococcus casseliflavus and Enterococcus gallinarum as causative agents of spontaneous bacterial peritonitis.

    PubMed

    Narciso-Schiavon, Janaína Luz; Borgonovo, Ariane; Marques, Paula Couto; Tonon, Débora; Bansho, Emilia Tiemi Oshiro; Maggi, Dariana Carla; Dantas-Corrêa, Esther Buzaglo; de Lucca Schiavon, Leonardo

    2015-01-01

    Infection by multidrug resistant bacteria is arousing as a relevant issue among hospitalized subjects and is of particular interest in patients with cirrhosis given the frequent use of broad spectrum antibiotics and their altered immune response. We report the first case report of spontaneous bacterial peritonitis (SBP) caused by Enterococcus casseliflavus and the sixth case of SBP caused by Enterococcus gallinarum.

  14. Genetic Diversity among Enterococcus faecalis

    PubMed Central

    McBride, Shonna M.; Fischetti, Vincent A.; LeBlanc, Donald J.; Moellering, Robert C.; Gilmore, Michael S.

    2007-01-01

    Enterococcus faecalis, a ubiquitous member of mammalian gastrointestinal flora, is a leading cause of nosocomial infections and a growing public health concern. The enterococci responsible for these infections are often resistant to multiple antibiotics and have become notorious for their ability to acquire and disseminate antibiotic resistances. In the current study, we examined genetic relationships among 106 strains of E. faecalis isolated over the past 100 years, including strains identified for their diversity and used historically for serotyping, strains that have been adapted for laboratory use, and isolates from previously described E. faecalis infection outbreaks. This collection also includes isolates first characterized as having novel plasmids, virulence traits, antibiotic resistances, and pathogenicity island (PAI) components. We evaluated variation in factors contributing to pathogenicity, including toxin production, antibiotic resistance, polymorphism in the capsule (cps) operon, pathogenicity island (PAI) gene content, and other accessory factors. This information was correlated with multi-locus sequence typing (MLST) data, which was used to define genetic lineages. Our findings show that virulence and antibiotic resistance traits can be found within many diverse lineages of E. faecalis. However, lineages have emerged that have caused infection outbreaks globally, in which several new antibiotic resistances have entered the species, and in which virulence traits have converged. Comparing genomic hybridization profiles, using a microarray, of strains identified by MLST as spanning the diversity of the species, allowed us to identify the core E. faecalis genome as consisting of an estimated 2057 unique genes. PMID:17611618

  15. Enterococcus saccharominimus sp. nov., from dairy products.

    PubMed

    Vancanneyt, M; Zamfir, M; Devriese, L A; Lefebvre, K; Engelbeen, K; Vandemeulebroecke, K; Amar, M; De Vuyst, L; Haesebrouck, F; Swings, J

    2004-11-01

    Four isolates, which were obtained from Belgian, Moroccan and Romanian dairy products, constituted a homogeneous but unidentified taxon after screening with whole-cell protein fingerprinting. Complete 16S rRNA gene sequence analysis classified representative strains in the genus Enterococcus. Highest sequence similarities of 98.6 and 98.0 % were obtained with the species Enterococcus sulfureus and Enterococcus saccharolyticus, respectively. Growth characteristics, biochemical features, tRNA intergenic length polymorphism analysis, DNA-DNA hybridization and DNA G+C contents of selected strains demonstrated that they represent a single, novel Enterococcus species. It differs phenotypically from other enterococci in characteristics commonly considered as typical of this genus: no growth in 6.5 % NaCl or 0.4 % sodium azide, and no acid production from a wide range of carbohydrates. The name Enterococcus saccharominimus sp. nov. is proposed for this novel species; the type strain (LMG 21727(T)=CCM 7220(T)) was isolated from contaminated pasteurized cow's milk.

  16. Proficiency of Clinical Laboratories in Spain in Detecting Vancomycin-Resistant Enterococcus spp.

    PubMed Central

    Alonso-Echanove, Juan; Robles, Belen; Jarvis, William R.

    1999-01-01

    Studies in a variety of U.S. clinical laboratories have demonstrated difficulty in detecting intermediate and low-level vancomycin-resistant enterococci (VRE). The misclassification of “at least intermediate resistant isolates” as vancomycin susceptible may have both clinical implications and a negative impact on measures to control the spread of VRE. No published study has assessed the ability of clinical laboratories in Europe to detect VRE. So, the apparent low prevalence of VRE in European hospitals may be, in part, secondary to the inability of these laboratories to detect all VRE. In an effort to assess European laboratories’ proficiency in detecting VRE, we identified 22 laboratories in Spain and asked them to test four VRE strains and one susceptible enterococcal strain from the Centers for Disease Control and Prevention collection. Each organism was tested by the routine antimicrobial susceptibility testing method used by each laboratory. Overall, VRE were correctly identified in 61 of 88 (69.1%) instances. The accuracy of VRE detection varied with the level of resistance and the antimicrobial susceptibility method. The high-level-resistant strain (Enterococcus faecium; MIC, 512 μg/ml) was accurately detected in 20 of 22 (91.3%) instances, whereas the intermediate-resistant isolate (Enterococcus gallinarum; MIC, 8 μg/ml) was accurately detected in only 11 of 22 (50%) instances. Classification errors occurred in 27 of 88 (30.9%) instances. Misclassification as vancomycin susceptible was the most common error (16 of 27 [59.3%] instances). Our study shows that the participating Spanish laboratories had an overall acceptable proficiency in detecting VRE but that a substantial proportion of VRE isolates with low or intermediate levels of resistance were not detected. We recommend that studies be conducted to validate laboratory proficiency testing as an important step in the prevention and control of the spread of antimicrobial resistance. PMID:10364577

  17. Academic Cloning.

    ERIC Educational Resources Information Center

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  18. TLR-7 activation enhances IL-22–mediated colonization resistance against vancomycin-resistant enterococcus

    PubMed Central

    Abt, Michael C.; Buffie, Charlie G.; Sušac, Bože; Becattini, Simone; Carter, Rebecca A.; Leiner, Ingrid; Keith, James W.; Artis, David; Osborne, Lisa C.; Pamer, Eric G.

    2016-01-01

    Antibiotic administration can disrupt the intestinal microbiota and down-regulate innate immune defenses, compromising colonization resistance against orally acquired bacterial pathogens. Vancomycin-resistant Enterococcus faecium (VRE), a major cause of antibiotic-resistant infections in hospitalized patients, thrives in the intestine when colonization resistance is compromised, achieving extremely high densities that can lead to bloodstream invasion and sepsis. Viral infections, by mechanisms that remain incompletely defined, can stimulate resistance against invading bacterial pathogens. We report that murine norovirus infection reduces the density of VRE in the intestinal tract of mice with antibiotic-induced loss of colonization resistance. Resiquimod (R848), a synthetic ligand for Toll-like receptor 7 (TLR-7) that stimulates antiviral innate immune defenses, restores expression of the antimicrobial peptide Reg3γ and reestablishes colonization resistance against VRE in antibiotic-treated mice. Orally administered R848 triggers TLR-7 on CD11c+ dendritic cells, inducing interleukin-23 (IL-23) expression followed by a burst of IL-22 secretion by innate lymphoid cells, leading to Reg3γ expression and restoration of colonization resistance against VRE. Our findings reveal that an orally bioavailable TLR-7 ligand that stimulates innate antiviral immune defenses in the intestine restores colonization resistance against a highly antibiotic-resistant bacterial pathogen. PMID:26912904

  19. Antimicrobial and antioxidant activities of Enterococcus species isolated from meat and dairy products.

    PubMed

    Pieniz, S; Andreazza, R; Okeke, B C; Camargo, F A O; Brandelli, A

    2015-11-01

    Lactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faecium species. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.

  20. Antimicrobial resistance in Enterococcus spp. isolated from environmental samples in an area of intensive poultry production.

    PubMed

    Furtula, Vesna; Jackson, Charlene R; Farrell, Erin Gwenn; Barrett, John B; Hiott, Lari M; Chambers, Patricia A

    2013-03-12

    Enterococcus spp. from two poultry farms and proximate surface and ground water sites in an area of intensive poultry production were tested for resistance to 16 clinical antibiotics. Resistance patterns were compared to assess trends and possible correlations for specific antimicrobials and levels of resistance. Enterococci were detected at all 12 surface water sites and three of 28 ground water sites. Resistance to lincomycin, tetracycline, penicillin and ciprofloxacin in poultry litter isolates was high (80.3%, 65.3%, 61.1% and 49.6%, respectively). Resistance in the surface water to the same antibiotics was 87.1%, 24.1%, 7.6% and 12.9%, respectively. Overall, 86% of litter isolates, 58% of surface water isolates and 100% of ground water isolates were resistant to more than one antibiotic. Fifty-four different resistance patterns were recognised in isolates obtained from litter and environmental samples and several E. faecium and E. faecalis isolates from litter and environment samples shared the same resistance pattern. Multiple antibiotic resistant (MAR) indices calculated to assess health risks due to the presence of resistant enterococci suggested an increased presence of antibiotics in surface water, likely from poultry sources as no other wastewater contributions in the area were documented.

  1. TLR-7 activation enhances IL-22-mediated colonization resistance against vancomycin-resistant enterococcus.

    PubMed

    Abt, Michael C; Buffie, Charlie G; Sušac, Bože; Becattini, Simone; Carter, Rebecca A; Leiner, Ingrid; Keith, James W; Artis, David; Osborne, Lisa C; Pamer, Eric G

    2016-02-24

    Antibiotic administration can disrupt the intestinal microbiota and down-regulate innate immune defenses, compromising colonization resistance against orally acquired bacterial pathogens. Vancomycin-resistant Enterococcus faecium (VRE), a major cause of antibiotic-resistant infections in hospitalized patients, thrives in the intestine when colonization resistance is compromised, achieving extremely high densities that can lead to bloodstream invasion and sepsis. Viral infections, by mechanisms that remain incompletely defined, can stimulate resistance against invading bacterial pathogens. We report that murine norovirus infection correlates with reduced density of VRE in the intestinal tract of mice with antibiotic-induced loss of colonization resistance. Resiquimod (R848), a synthetic ligand for Toll-like receptor 7 (TLR-7) that stimulates antiviral innate immune defenses, restores expression of the antimicrobial peptide Reg3γ and reestablishes colonization resistance against VRE in antibiotic-treated mice. Orally administered R848 triggers TLR-7 on CD11c(+) dendritic cells, inducing interleukin-23 (IL-23) expression followed by a burst of IL-22 secretion by innate lymphoid cells, leading to Reg3γ expression and restoration of colonization resistance against VRE. Our findings reveal that an orally bioavailable TLR-7 ligand that stimulates innate antiviral immune pathways in the intestine restores colonization resistance against a highly antibiotic-resistant bacterial pathogen.

  2. 9230 FECAL ENTEROCOCCUS/STREPTOCOCCUS GROUPS

    EPA Science Inventory

    In 1903 the genus name Enterococcus was proposed for gram-positive, catalase-negative, coccoid-shaped bacterial of intestinal origin. Several years later, it was suggested that the genus name be changed to Streptococcus because of the organisms' ability to form chains of coccoid...

  3. Enterococcus plantarum sp. nov., isolated from plants.

    PubMed

    Svec, Pavel; Vandamme, Peter; Bryndová, Hana; Holochová, Pavla; Kosina, Marcel; Maslanová, Ivana; Sedlácek, Ivo

    2012-07-01

    Eight Gram-positive, catalase-negative bacterial strains were isolated during screening of enterococcal populations on plants. rep-PCR fingerprinting using the (GTG)(5) primer showed that the isolates constituted a single cluster that was separate from all known enterococcal species. 16S rRNA gene sequence phylogenetic analysis of three representative strains showed that the isolates belonged to the genus Enterococcus and that they clustered with the Enterococcus faecalis species group. Sequencing of the genes for the phenylalanyl-tRNA synthase alpha subunit (pheS) and the RNA polymerase alpha subunit (rpoA) also revealed the isolates' separate taxonomic position. Application of whole-cell protein fingerprinting, automated ribotyping and extensive phenotyping demonstrated the genetic and phenotypic homogeneity of the isolates and confirmed their separate position within the E. faecalis species group. The isolates represent a novel species of the genus Enterococcus, for which the name Enterococcus plantarum sp. nov. is proposed; the type strain is CCM 7889(T) (=LMG 26214(T)=C27(T)).

  4. Antimicrobial resistant Escherichia coli and Enterococcus spp. isolated from Miranda Donkey (Equus asinus): an old problem from a new source with a different approach.

    PubMed

    Carvalho, Isabel; Del Campo, Rosa; Sousa, Margarida; Silva, Nuno; Carrola, João; Marinho, Catarina; Santos, Tiago; Carvalho, Silvia; Nóvoa, Miguel; Quaresma, Miguel; Pereira, José Eduardo; Cobo, Marta; Igrejas, Gilberto; Poeta, Patricia

    2017-01-05

    The Miranda Donkey (Equus asinus) is an endangered asinine from Miranda do Douro region, located in North East of Portugal. We study the antimicrobial resistance (AMR) and virulence genes in Escherichia coli and Enterococcus spp. isolates from these animals. In March 2014, a total of 66 faecal samples were recovered from independent animals. Antibiotic resistance was determined by the disk diffusion method. Carriage of genes codifying for antibiotic resistant and virulent factors was analyzed by polymerase chain reaction (PCR). A total of 66 E. coli and 41 enterococci isolates were detected, being the most prevalent species Enterococcus faecium (61%) and Enterococcus hirae (24%). For enterococcal isolates, high percentages of resistant rates to tetracycline (68.3%), quinupristin/dalfopristin (51.2%) and ciprofloxacin (48.8%) were observed. The erm(A) and/or erm(B), tet(M) and/or tet(L), vat(D) and/or vat(E) and aph(3')-IIIa genes were also found. The most frequent virulence gene detected was gel(E), followed by ace, cpd and hyl. E. coli isolates were highly resistant to streptomycin (78%), whereas 39% of them exhibited resistance to aminoglycosides and tetracycline. sul1 and/or sul2 genes were detected in 66.7% of trimethoprim-sulfamethoxazole resistant isolates. The virulence genes detected were fim(A) (46%) and cnf1 (27%). To the best of our knowledge, this is the first report showing antibiotic resistance among E. coli and Enterococcus spp. Isolates from Miranda Donkey in Portugal, pointed out as possible antibiotic-resistant bacteria reservoirs. Although the detection of these resistances they present low risk for other animals as well as for human being, in that rural area context.

  5. [Investigation of Enterococcus faecalis antimicrobial resistance].

    PubMed

    Casal, M M; Cause, M; Solís, F; Rodríz, F; Casal, M

    2009-09-01

    We performed an antibiotic resistance study on Enterococcus faecalis isolated from intrahospitalary and extrahospitalary samples between january 2004 and january 2008. Three different samples were studied; urine, blood and wound swabs, considering a strain per patient. We included in the study a global amount of 3,641 Enterococcus faecalis isolations from clinical samples received at Hospital Universitario Reina Sofía microbiology service in Córdoba (Spain). We employed semiautomatic system WIDER I (Soria Melguizo) for identification and sensibility testing. We considered sensibility and resistance criteria recommended by MENSURA group. We found a sensitivity rate of 98.04% to betalactamics.The highest resistance rates were obtained with aminoglycosides, between 33.82% and 48.01%. Linezolid and Vancomycin sensitivity was 100%. It seems that vancomycin resistance is not a worrying issue today, but it should be controlled.

  6. Determination of antimicrobial resistance of Enterococcus strains isolated from pigs and their genotypic characterization by method of amplification of DNA fragments surrounding rare restriction sites (the ADSRRS-fingerprinting).

    PubMed

    Nowakiewicz, Aneta; Ziółkowska, Grażyna; Trościańczyk, Aleksandra; Zięba, Przemysław; Gnat, Sebastian

    2016-11-28

    In this study, we analysed phenotypic resistance profiles and their reflection in the genomic profiles of Enterococcus spp. strains isolated from pigs raised on different farms. Samples were collected from five pig farms (n=90 animals) and tested for Enterococcus. Minimum inhibitory concentrations of 12 antimicrobials were determined using the broth microdilution method, and epidemiological molecular analysis of strains belonging to selected species (E. faecalis, E. faecium and E. hirae) was performed using the ADSRRS-fingerprinting method with a few modifications. The highest percentage of strains were resistant to tetracycline (73.4%), erythromycin and tylosin (42.5%), and rifampicin (25.2%) as well as a large number exhibited high-level resistance to both kanamycin (25.2%) and streptomycin (27.6%). The strains of E. faecalis, E. faecium and E. hirae (n=184) revealed varied phenotypic resistance profiles, among which as many as seven met the criteria for multi-drug resistance (30,4% of strains tested). ADSRRS-fingerprinting analysis produced 17 genotypic profiles of individual strains which were correlated with their phenotypic resistance profiles. Only E. hirae strains susceptible to all of the chemotherapeutics tested had two different ADSRRS profiles. Moreover, eight animals were carriers of more than one genotype belonging to the same Enterococcus spp., mainly E. faecalis. Given the possibility of transmission to humans of the high resistance/multi-drug resistance enterococci and the significant role of pigs as food animals in this process, it is necessary to introduce a multi-level control strategy by carrying out research on the resistance and molecular characteristics of indicator bacterial strains isolated from animals on individual farms.

  7. Rapid detection of Enterococcus spp. direct from blood culture bottles using Enterococcus QuickFISH method: a multicenter investigation.

    PubMed

    Deck, Melissa K; Anderson, Erica S; Buckner, Rebecca J; Colasante, Georgia; Davis, Thomas E; Coull, James M; Crystal, Benjamin; Latta, Phyllis Della; Fuchs, Martin; Fuller, Deanna; Harris, Will; Hazen, Kevin; Klimas, Lisa L; Lindao, Daniel; Meltzer, Michelle C; Morgan, Margie; Shepard, Janeen; Stevens, Sharon; Wu, Fann; Fiandaca, Mark J

    2014-04-01

    The performance of a diagnostic method for detection and identification of Enterococcus spp. directly from positive blood culture was evaluated in a clinical study. The method, Enterococcus QuickFISH BC, is a second-generation peptide nucleic acid (PNA) fluorescence in situ hybridization (FISH) test, which uses a simplified, faster assay procedure. The test uses fluorescently labeled PNA probes targeting 16S rRNA to differentiate Enterococcus faecalis from other Enterococcus spp. by the color of the cellular fluorescence. Three hundred fifty-six routine blood culture samples were tested; only 2 discordant results were recorded. The sensitivities for detection of Enterococcus faecalis and non-faecalis Enterococcus were 100% (106/106) and 97.0% (65/67), respectively, and the combined specificity of the assay was 100%. The combined positive and negative predictive values of the assay were 100% (171/171) and 98.9% (185/187), respectively.

  8. Molecular cloning.

    PubMed

    Lessard, Juliane C

    2013-01-01

    This protocol describes the basic steps involved in conventional plasmid-based cloning. The goals are to insert a DNA fragment of interest into a receiving vector plasmid, transform the plasmid into E. coli, recover the plasmid DNA, and check for correct insertion events.

  9. Molecular typing, pathogenicity factor genes and antimicrobial susceptibility of vancomycin resistant enterococci in Belgrade, Serbia.

    PubMed

    Jovanović, Milica; Milošević, Branko; Tošić, Tanja; Stevanović, Goran; Mioljević, Vesna; Inđić, Nikola; Velebit, Branko; Zervos, Marcus

    2015-06-01

    In this study the distribution of species and antimicrobial resistance among vancomycin resistant enterococci (VRE) recovered from clinical specimens obtained from five hospitals in Belgrade was analyzed. Strains were further characterized by pulsed-field gel electrophoresis (PFGE). Polymerase chain reaction (PCR) was used to investigate the presence of vanA and vanB genes and pathogenicity factor genes. Identification of 194 VRE isolates revealed 154 Enterococcus faecium, 21 Enterococcus faecalis, 10 Enterococcus raffinosus and 9 Enterococcus gallinarum. This study revealed existence of 8 major clones of VRE. PCR determined vanA gene to be present in all of the VRE studied. Esp and hyl genes were present in 29.22% and 27.92% of E. faecium, respectively, and in 76.19% and 0 of E. faecalis, respectively. Esp and hyl genes were not found more frequently in members of predominant clones of E. faecium than in single isolates; nor was their presence connected to invasiveness.

  10. Pheromone-inducible conjugation in Enterococcus faecalis

    PubMed Central

    Kozlowicz, Briana K.; Dworkin, Martin; Dunny, Gary M.

    2009-01-01

    Pheromone-inducible transfer of the plasmid pCF10 in Enterococcus faecalis is regulated using a complicated network of proteins and RNAs. The plasmid itself has been assembled from parts garnered from a variety of sources, and many aspects of the system resemble a biological kluge. Recently several new functions of various pCF10 gene products that participate in regulation of plasmid transfer have been identified. The results indicate that selective pressures controlling the evolution of the plasmid have produced a highly complex regulatory network with multiple biological functions that may serve well as a model for the evolution of biological complexity. PMID:16503196

  11. Bacteriocin protein BacL1 of Enterococcus faecalis targets cell division loci and specifically recognizes L-Ala2-cross-bridged peptidoglycan.

    PubMed

    Kurushima, Jun; Nakane, Daisuke; Nishizaka, Takayuki; Tomita, Haruyoshi

    2015-01-01

    Bacteriocin 41 (Bac41) is produced from clinical isolates of Enterococcus faecalis and consists of two extracellular proteins, BacL1 and BacA. We previously reported that BacL1 protein (595 amino acids, 64.5 kDa) is a bacteriolytic peptidoglycan D-isoglutamyl-L-lysine endopeptidase that induces cell lysis of E. faecalis when an accessory factor, BacA, is copresent. However, the target of BacL1 remains unknown. In this study, we investigated the targeting specificity of BacL1. Fluorescence microscopy analysis using fluorescent dye-conjugated recombinant protein demonstrated that BacL1 specifically localized at the cell division-associated site, including the equatorial ring, division septum, and nascent cell wall, on the cell surface of target E. faecalis cells. This specific targeting was dependent on the triple repeat of the SH3 domain located in the region from amino acid 329 to 590 of BacL1. Repression of cell growth due to the stationary state of the growth phase or to treatment with bacteriostatic antibiotics rescued bacteria from the bacteriolytic activity of BacL1 and BacA. The static growth state also abolished the binding and targeting of BacL1 to the cell division-associated site. Furthermore, the targeting of BacL1 was detectable among Gram-positive bacteria with an L-Ala-L-Ala-cross-bridging peptidoglycan, including E. faecalis, Streptococcus pyogenes, or Streptococcus pneumoniae, but not among bacteria with alternate peptidoglycan structures, such as Enterococcus faecium, Enterococcus hirae, Staphylococcus aureus, or Listeria monocytogenes. These data suggest that BacL1 specifically targets the L-Ala-L-Ala-cross-bridged peptidoglycan and potentially lyses the E. faecalis cells during cell division.

  12. Modified 16S-23S rRNA intergenic region restriction endonuclease analysis for species identification of Enterococcus strains isolated from pigs, compared with identification using classical methods and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Nowakiewicz, Aneta; Ziółkowska, Grażyna; Zięba, Przemysław; Trościańczyk, Aleksandra; Banach, Tomasz; Kowalski, Cezary

    2015-03-01

    Fast and reliable identification of bacteria to at least the species level is currently the basis for correct diagnosis and appropriate treatment of infections. This is particularly important in the case of bacteria of the genus Enterococcus, whose resistance profile is often correlated with their species (e.g. resistance to vancomycin). In this study, we evaluated restriction endonuclease analysis of the 16S-23S rRNA gene intergenic transcribed spacer (ITS) region for species identification of Enterococcus. The utility of the method was compared with that of phenotypic methods [biochemical profile evaluation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)]. Identification was based on 21 Enterococcus reference strains, of the species E. faecalis, E. faecium, E. hirae, E. durans, E. casseliflavus, E. gallinarum, E. avium, E. cecorum and E. columbae, and 47 Enterococcus field strains isolated from pigs. Restriction endonuclease analysis of the ITS-PCR product using HinfI, RsaI and MboI, in the order specified, enabled species differentiation of the Enterococcus reference and field strains, and in the case of the latter, the results of species identification were identical (47/47) to those obtained by MALDI-TOF MS. Moreover, as a result of digestion with MboI, a unique restriction profile was also obtained for the strains (3/3) identified by MALDI-TOF MS as E. thailandicus. In our opinion, restriction endonuclease analysis of the 16S-23S rRNA gene ITS region of Enterococcus may be a simple and relatively fast (less than 4 h) alternative method for identifying the species occurring most frequently in humans and animals.

  13. Resistance of Enterococcus strains isolated from pigs to gastrointestinal tract and antagonistic effect against Escherichia coli K88.

    PubMed

    García-Galaz, Alfonso; Pérez-Morales, Rosalva; Díaz-Cinco, Martha; Acedo-Félix, Evelia

    2004-01-01

    The intestinal flora plays an important role in health and wellbeing of different organisms. Indigenous microflora can be innocuous or pathogenic. Consumption of food supplemented with beneficial microorganisms as probiotics provides a good health state and this can be maintained and recovered. Currently, probiotic strains of Bifidobacterium and Lactobacillus are widely used in humans as well as animals. Swine industry would benefit with the application of probiotics, mainly to overcome diarrheal diseases produced by different causes, as a pathogenic E. coli K88. The aim of this work was to isolate strains of Enterococcus from gastrointestinal tract of pigs to use them as probiotic. Two strains of E. faecalis, 2 of E. mundii and 7 of E. faecium were isolated with characteristics of resistance to acid pH, tolerance to biliary salts and a high antagonistic activity (>80%) against E. coli K88. Based on their characteristics and species affinity, we believe that these strains could be administered to pigs as a probiotic.

  14. Characterization of an Enterococcus gallinarum Isolate Carrying a Dual vanA and vanB Cassette

    PubMed Central

    Eshaghi, Alireza; Shahinas, Dea; Li, Aimin; Kariyawasam, Ruwandi; Banh, Philip; Desjardins, Marc; Melano, Roberto G.

    2015-01-01

    The ability of vancomycin resistance determinants to be horizontally transferred within enterococci species is a concern. Identification and characterization of vancomycin-resistant enterococci (VRE) in a clinical isolate have a significant impact on infection control practices. In this study, we describe a clinical isolate of Enterococcus gallinarum exhibiting high-level resistance to vancomycin and teicoplanin. The genetic characterization of this isolate showed the presence of vanA and vanB genes in addition to the naturally carried vanC gene. vanA was identified on pA6981, a 35,608-bp circular plasmid with significant homology to plasmid pS177. The vanB operon was integrated into the bacterial chromosome and showed a high level of homology to previously reported Tn1549 and Tn5382. To the best of our knowledge, this is the first report of E. gallinarum carrying both vanA and vanB operons, indicating the importance of identifying the vancomycin resistance mechanism in non-E. faecium and non-E. faecalis enterococcal species. PMID:25948610

  15. High Level Aminoglycoside Resistance and Distribution of Aminoglycoside Resistant Genes among Clinical Isolates of Enterococcus Species in Chennai, India

    PubMed Central

    Padmasini, Elango; Padmaraj, R.; Ramesh, S. Srivani

    2014-01-01

    Enterococci are nosocomial pathogen with multiple-drug resistance by intrinsic and extrinsic mechanisms. Aminoglycosides along with cell wall inhibitors are given clinically for treating enterococcal infections. 178 enterococcal isolates were analyzed in this study. E. faecalis is identified to be the predominant Enterococcus species, along with E. faecium, E. avium, E. hirae, E. durans, E. dispar and E. gallinarum. High level aminoglycoside resistance (HLAR) by MIC for gentamicin (GM), streptomycin (SM) and both (GM + SM) antibiotics was found to be 42.7%, 29.8%, and 21.9%, respectively. Detection of aminoglycoside modifying enzyme encoding genes (AME) in enterococci was identified by multiplex PCR for aac(6′)-Ie-aph(2′′)-Ia; aph(2′′)-Ib; aph(2′′)-Ic; aph(2′′)-Id and aph(3′)-IIIa genes. 38.2% isolates carried aac(6′)-Ie-aph(2′′)-Ia gene and 40.4% isolates carried aph(3′)-IIIa gene. aph(2′′)-Ib; aph(2′′)-Ic; aph(2′′)-Id were not detected among our study isolates. aac(6′)-Ie-aph(2′′)-Ia and aph(3′)-IIIa genes were also observed in HLAR E. durans, E. avium, E. hirae, and E. gallinarum isolates. This indicates that high level aminoglycoside resistance genes are widely disseminated among isolates of enterococci from Chennai. PMID:24672306

  16. Characterization of an Enterococcus gallinarum Isolate Carrying a Dual vanA and vanB Cassette.

    PubMed

    Eshaghi, Alireza; Shahinas, Dea; Li, Aimin; Kariyawasam, Ruwandi; Banh, Philip; Desjardins, Marc; Melano, Roberto G; Patel, Samir N

    2015-07-01

    The ability of vancomycin resistance determinants to be horizontally transferred within enterococci species is a concern. Identification and characterization of vancomycin-resistant enterococci (VRE) in a clinical isolate have a significant impact on infection control practices. In this study, we describe a clinical isolate of Enterococcus gallinarum exhibiting high-level resistance to vancomycin and teicoplanin. The genetic characterization of this isolate showed the presence of vanA and vanB genes in addition to the naturally carried vanC gene. vanA was identified on pA6981, a 35,608-bp circular plasmid with significant homology to plasmid pS177. The vanB operon was integrated into the bacterial chromosome and showed a high level of homology to previously reported Tn1549 and Tn5382. To the best of our knowledge, this is the first report of E. gallinarum carrying both vanA and vanB operons, indicating the importance of identifying the vancomycin resistance mechanism in non-E. faecium and non-E. faecalis enterococcal species.

  17. [Eugenics and human cloning].

    PubMed

    Boloz, W

    2001-01-01

    Because of legislative bans there are still no reports of human cloning. However eager public debate is currently running, concerning medical, legal, social and ethical aspects of human cloning. Arguments for and against human cloning are presented. An important argument against cloning is the danger of eugenic tendencies connected with cloning, which could lead to genetic discrimination.

  18. Antimicrobial resistance of Enterococcus species from meat and fermented meat products isolated by a PCR-based rapid screening method.

    PubMed

    Jahan, Musarrat; Krause, Denis O; Holley, Richard A

    2013-05-15

    Enterococci are predominantly found in the gastrointestinal tract of humans and animals, but species commonly resident on vegetation are known. Their presence in large numbers in foods may indicate a lapse in sanitation and their ability to serve as a genetic reservoir of transferable antibiotic resistance is of concern. Conventional culture methods for identification of enterococci are slow and sometimes give false results because of the biochemical diversity of the organisms in this genus. This work reports the development of a PCR-based assay to detect enterococci at the genus level by targeting a 16S rRNA sequence. Published 16S rRNA sequences were aligned and used to design genus specific primers (EntF and EntR). The primers were able to amplify a 678 bp target region from Enterococcus faecalis ATCC 7080 and 20 other strains of enterococci from 11 different species, but there was no amplification by 32 species from closely related genera (Pediococcus, Lactobacillus, Streptococcus and Listeria) or species of Escherichia coli and Salmonella. The PCR positive samples were plated, screened by a colony patch technique and their identities were confirmed by API 20 Strep panels and sequencing. When dry fermented sausage and ham as well as fresh meat batter for dry cured sausage manufacture were tested for enterococci by the method, 29 Enterococcus strains (15 E. faecalis, 13 E. faecium, and one E. gallinarum) were identified. When susceptibility of these enterococci to 12 antibiotics was tested, the highest incidence of resistance was to clindamycin (89.6%), followed by tetracycline hydrochloride (65.5%), tylosin (62%), erythromycin (45%), streptomycin and neomycin (17%), chloramphenicol (10.3%), penicillin (10.3%), ciprofloxacin (10.3%) and gentamicin (3.4%). None was resistant to the clinically important drugs vancomycin or ampicillin. Most strains (27/29) were resistant to more than one antibiotic while 17 of 29 strains were resistant to three to 8 antibiotics

  19. [Vancomycin and high-level aminoglycoside resistant Enterococcus carriage and the risk factors related to resistance in hospitalized patients].

    PubMed

    Yildirim, Mustafa; Sencan, Irfan; Ozdemir, Davut; Oksüz, Sükrü; Yilmaz, Zeynep; Sahin, Idris

    2007-04-01

    The aims of this study were to detect the prevalence of fecal vancomycin resistant Enterococcus (VRE) colonization with high-level resistance to aminoglycoside and other antibiotics and, the risk factors related to resistance in hospitalized patients in Düzce Medical Faculty Hospital, Turkey. A total of 105 patients (61 from internal medicine, 44 from surgery clinics; 54.3% female, mean age: 47.2 +/- 24.54 years) were included to the study and a single stool sample was collected from each of the patients. Specimens were cultivated in Enterococcus selective media (BioMerieux, France), and the isolates were identified by conventional microbiological methods together with the API 20 Strep test. Beta-lactamase activities of the isolates were tested with nitrocefin disk, and antibiotic susceptibilities were determined by the disk diffusion method. Enterococcus spp. were isolated from 81 (77%) of the patients' samples and 60.5% were identified as E. faecium, 13.6% as E. faecalis, 11.1% as E. gallinarum, 7.4% as E. durans, 2.5% as E. raffinosus, 2.5% as E. mundtii, 1.2% as E. casseliflavus, and 1.2% as E. avium. High-level streptomycin and gentamicin resistance rates were found in 19.8% and 9.9% of the isolates, respectively. The resistance rates for the other antibiotics were found as follows; 18.5% to ampicillin, 27.2% to penicilin, 34.6% to nitrofurantoin, 65.4% to norfloxacin, and 70.4% to both tetracycline and ciprofloxacin. No vancomycin resistance was detected, and none of the enterococci had beta-lactamase activity. Long hospitalization period, antibiotic usage and experience of intra-abdominal operation were found as the significant risk factors for colonization of the resistant bacteria. Our results demonstrated that there was no fecal VRE carriage in our hospital during the study period, however, it was concluded that the screening tests should be done periodically in order to detect resistant strains as soon as possible.

  20. Enterococcus hirae Bacteremia Associated with Acute Pancreatitis and Septic Shock

    PubMed Central

    Dicpinigaitis, Peter V.; De Aguirre, Manuel; Divito, Joseph

    2015-01-01

    Infection with Enterococcus hirae has rarely been reported in humans but is not uncommon in mammals and birds. We describe a case of Enterococcus hirae bacteremia associated with acute pancreatitis, acute cholecystitis, and septic shock responsive to antibiotic therapy and supportive critical care management. Unique aspects of this case of Enterococcus hirae bacteremia are its association with acute pancreatitis and its geographical origin. To our knowledge, this is the first report of Enterococcus hirae bacteremia occurring in a patient in the United States. Although human infection with this organism appears to be rare, all cases reported to date describe bacteremia associated with severe and life-threatening illness. Thus, physicians need to be cognizant of the clinical significance of this heretofore little recognized pathogen. PMID:26417465

  1. Complete genome sequence of Brachybacterium faecium type strain (Schefferle 6-10T)

    SciTech Connect

    Lapidus, Alla; Pukall, Rudiger; LaButti, Kurt; Copeland, Alex; Glavina Del Rio, Tijana; Nolan, Matt; Chen, Feng; Lucas, Susan; Tice, Hope; Cheng, Jan-Fang; Bruce, David; Goodwin, Lynne; Pitluck, Sam; Rohde, Manfred; Goker, Markus; Pati, Amrita; Ivanova, Natalia; Mavrommatis, Konstantinos; Chen, Amy; Palaniappan, Krishna; D'haeseleer, Patrik; Chain, Patrick; Bristow, Jim; Eisen, Johnathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C.; Klenk, Hans-Peter

    2009-05-20

    Brachybacterium faecium Collins et al. 1988 is the type species of the genus, and is of phylogenetic interest because of its location in the Dermabacteraceae, a rather isolated family within the actinobacterial suborder Micrococcineae. B. faecium is known for its rod-coccus growth cycle and the ability to degrade uric acid. It grows aerobically or weakly anaerobically. The strain described in this report is a free-living, nonmotile, Gram-positive bacterium, originally isolated from poultry deep litter. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of a member of the actinobacterial family Dermabacteraceae, and the 3,614,992 bp long single replicon genome with its 3129 protein-coding and 69 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  2. The Clone Factory

    ERIC Educational Resources Information Center

    Stoddard, Beryl

    2005-01-01

    Have humans been cloned? Is it possible? Immediate interest is sparked when students are asked these questions. In response to their curiosity, the clone factory activity was developed to help them understand the process of cloning. In this activity, students reenact the cloning process, in a very simplified simulation. After completing the…

  3. Antimicrobial susceptibility and distribution of antimicrobial-resistance genes among Enterococcus and coagulase-negative Staphylococcus isolates recovered from poultry litter.

    PubMed

    Simjee, Shabbir; McDermott, Patrick F; White, David G; Hofacre, Charles; Berghaus, Roy D; Carter, Peggy J; Stewart, Leigh; Liu, Tongrui; Maier, Marie; Maurer, John J

    2007-12-01

    Data on the prevalence of antimicrobial resistant enterococci and staphylococci from the poultry production environment are sparse in the United States. This information is needed for science-based risk assessments of antimicrobial use in animal husbandry and potential public-health consequences. In this study, we assessed the susceptibility of staphylococci and enterococci isolated from poultry litter, recovered from 24 farms across Georgia, to several antimicrobials of veterinary and human health importance. Among the 90 Enterococcus isolates recovered, E. hirae (46%) was the most frequently encountered species, followed by E. faecium (27%), E. gallinarum (12%), and E. faecalis (10%). Antimicrobial resistance was most often observed to tetracycline (96%), followed by clindamycin (90%), quinupristin-dalfopristin (62%), penicillin (53%), erythromycin (50%), nitrofurantoin (49%), and clarithromycin (48%). Among the 110 staphylococci isolates recovered, only coagulase-negative staphylococci (CNS) were identified with the predominant Staphylococcus species being S. sciuri (38%), S. lentus (21%), S. xylosus (14%) and S. simulans (12%). Resistance was less-frequently observed among the Staphylococcus isolates for the majority of antimicrobials tested, as compared with Enterococcus isolates, and was primarily limited to clarithromycin (71%), erythromycin (71%), clindamycin (48%), and tetracycline (38%). Multidrug resistance (MDR) phenotypes were prevalent in both Enterococcus and Staphylococcus; however, Enterococcus exhibited a statistically significant difference in the median number of antimicrobials to which resistance was observed (median = 5.0) compared with Staphylococcus species (median = 3.0). Because resistance to several of these antimicrobials in gram-positive bacteria may be attributed to the shuttling of common drug-resistance genes, we also determined which common antimicrobial-resistance genes were present in both enterococci and staphylococci. The

  4. Enterococcus durans EP1 a Promising Anti-inflammatory Probiotic Able to Stimulate sIgA and to Increase Faecalibacterium prausnitzii Abundance.

    PubMed

    Carasi, Paula; Racedo, Silvia María; Jacquot, Claudine; Elie, Anne Marie; Serradell, María de Los Ángeles; Urdaci, María C

    2017-01-01

    Enterococcus species, principally Enterococcus faecium are used as probiotics since a long time with preference in animal applications but safety considerations were updated and also new uses as probiotics can be envisaged. Fifteen Enterococcus strains isolated from different foods were identified and analyzed for virulence factors and antibiotic resistance. Three Enterococcus durans strains were selected to study their immunomodulatory properties on PBMC and Caco2 cells. Two strains presented a profile toward a mild inflammatory Th1 response considering TNF-α/IL-10 and IL-1β/IL-10 cytokines ratios. The third strain EP1, presented an anti-inflammatory potential and was selected for in vivo studies. In mice, the strain was well tolerated and did not cause any adverse effects. EP1 administration increased the amount of IgA+ cells in mesenteric lymph node (MLN) after 7 days of administration. In fecal samples, the IgA content increased gradually and significantly from day 7 to day 21 in treated group. Additionally, IL-17, IL-6, IL-1β, IFN-γ, and CXCL1 gene expression significantly decreased on day 21 in Peyer's patches and IL-17 decreased in MLN. Mice treated with the probiotic showed significant lower mRNA levels of pro-inflammatory cytokines and mucins in the ileum at day 7 while their expression was normalized at day 21. Colonic expression of il-1β, il6, and mucins remain diminished at day 21. Ileum and colon explants from treated mice stimulated in vitro with LPS showed a significant reduction in IL-6 and an increase in IL-10 secretion suggesting an in vivo protective effect of the probiotic treatment against a proinflammatory stimulus. Interestingly, analysis of feces microbiota demonstrated that EP1 administration increase the amount of Faecalibacterium prausnitzii, a butyrate-producing bacteria, which is known for its anti-inflammatory effects. In conclusion, we demonstrated that EP1 strain is a strong sIgA inducer and possess mucosal anti

  5. Enterococcus durans EP1 a Promising Anti-inflammatory Probiotic Able to Stimulate sIgA and to Increase Faecalibacterium prausnitzii Abundance

    PubMed Central

    Carasi, Paula; Racedo, Silvia María; Jacquot, Claudine; Elie, Anne Marie; Serradell, María de los Ángeles; Urdaci, María C.

    2017-01-01

    Enterococcus species, principally Enterococcus faecium are used as probiotics since a long time with preference in animal applications but safety considerations were updated and also new uses as probiotics can be envisaged. Fifteen Enterococcus strains isolated from different foods were identified and analyzed for virulence factors and antibiotic resistance. Three Enterococcus durans strains were selected to study their immunomodulatory properties on PBMC and Caco2 cells. Two strains presented a profile toward a mild inflammatory Th1 response considering TNF-α/IL-10 and IL-1β/IL-10 cytokines ratios. The third strain EP1, presented an anti-inflammatory potential and was selected for in vivo studies. In mice, the strain was well tolerated and did not cause any adverse effects. EP1 administration increased the amount of IgA+ cells in mesenteric lymph node (MLN) after 7 days of administration. In fecal samples, the IgA content increased gradually and significantly from day 7 to day 21 in treated group. Additionally, IL-17, IL-6, IL-1β, IFN-γ, and CXCL1 gene expression significantly decreased on day 21 in Peyer’s patches and IL-17 decreased in MLN. Mice treated with the probiotic showed significant lower mRNA levels of pro-inflammatory cytokines and mucins in the ileum at day 7 while their expression was normalized at day 21. Colonic expression of il-1β, il6, and mucins remain diminished at day 21. Ileum and colon explants from treated mice stimulated in vitro with LPS showed a significant reduction in IL-6 and an increase in IL-10 secretion suggesting an in vivo protective effect of the probiotic treatment against a proinflammatory stimulus. Interestingly, analysis of feces microbiota demonstrated that EP1 administration increase the amount of Faecalibacterium prausnitzii, a butyrate-producing bacteria, which is known for its anti-inflammatory effects. In conclusion, we demonstrated that EP1 strain is a strong sIgA inducer and possess mucosal anti

  6. Chemical improvement of chitosan-modified beads for the immobilization of Enterococcus faecium DBFIQ E36 L-arabinose isomerase through multipoint covalent attachment approach.

    PubMed

    Manzo, Ricardo M; de Sousa, Marylane; Fenoglio, Cecilia L; Gonçalves, Luciana Rocha Barro; Mammarella, Enrique J

    2015-10-01

    D-tagatose is produced from D-galactose by the enzyme L-arabinose isomerase (L-AI) in a commercially viable bioprocess. An active and stable biocatalyst was obtained by modifying chitosan gel structure through reaction with TNBS, D-fructose or DMF, among others. This led to a significant improvement in L-AI immobilization via multipoint covalent attachment approach. Synthetized derivatives were compared with commercial supports such as Eupergit(®) C250L and glyoxal-agarose. The best chitosan derivative for L-AI immobilization was achieved by reacting 4 % (w/v) D-fructose with 3 % (w/v) chitosan at 50 °C for 4 h. When compared to the free enzyme, the glutaraldehyde-activated chitosan biocatalyst showed an apparent activity of 88.4 U g (gel) (-1) with a 211-fold stabilization factor while the glyoxal-agarose biocatalyst gave an apparent activity of 161.8 U g (gel) (-1) with an 85-fold stabilization factor. Hence, chitosan derivatives were comparable to commercial resins, thus becoming a viable low-cost strategy to obtain high active L-AI insolubilized derivatives.

  7. Transcriptional response of Enterococcus faecalis to sunlight.

    PubMed

    Sassoubre, Lauren M; Ramsey, Matthew M; Gilmore, Michael S; Boehm, Alexandria B

    2014-01-05

    Microarrays were used to investigate the transcriptional response of Enterococcus faecalis to photostress. E. faecalis are Gram-positive bacteria used as indicators of water quality and have been shown to vary diurnally in response to sunlight. E. faecalis in filtered seawater microcosms were exposed to artificial sunlight for 12h and then placed in the dark for 12h. Transcript abundance was measured at 0, 2, 6, 12, and 24h in the sunlit microcosm and a dark control using microarrays. Culturable E. faecalis concentrations decreased 6-7 orders of magnitude within the first 6h of light exposure. After 12h in the dark, no evidence of dark-repair was observed. Expression data collected after 12h of sunlight exposure revealed a difference in transcript abundance in the light relative to dark microcosms for 35 unique ORFs, 33 ORFs showed increased transcript abundance and 2 ORFs showed reduced transcript abundance. A majority (51%) of the ORFs with increased transcript abundance in the sunlit relative to dark microcosms encoded hypothetical proteins; others were associated with protein synthesis, oxidative stress and DNA repair. Results suggest that E. faecalis exposed to sunlight actively transcribe RNA in response to photostress.

  8. Enterococcus cecorum infection in a racing pigeon.

    PubMed

    Jung, Arne; Teske, Lydia; Rautenschlein, Silke

    2014-12-01

    Until now, Enterococcus cecorum (EC) has been known as a pathogen for broilers, broiler breeders, and Pekin ducks. In the present report, we describe a fatal systemic EC infection in a young racing pigeon (Columba livia forma domestica). EC was isolated from the heart, liver, spleen, and intestine of the bird in pure culture. In the pathologic examination, the pigeon showed enteritis and an ulcerative gastritis, which may have been predisposing factors for the development of the generalized EC infection. An accumulation of gram-positive cocci in spleen tissue was found in the histopathologic examination and confirms the presence of a systemic EC infection in the pigeon. Additionally, EC was isolated from cloacal swabs of other pigeons in the same loft, but no additional pigeons were submitted for necropsy. All EC isolates tested were negative by PCR for the enterococcal virulence factors cytolysin, enterococcal surface protein, aggregation substance, hyaluronidase, and gelatinase. Therefore, the reason for the enhanced virulence of the EC isolate remains unknown. Our report confirms EC as a disease-causing agent in pigeons and presents the first data concerning the analysis of EC for virulence factors.

  9. Peptide pheromone signaling in Streptococcus and Enterococcus

    PubMed Central

    Cook, Laura C.; Federle, Michael J.

    2014-01-01

    Intercellular chemical signaling in bacteria, commonly referred to as quorum sensing (QS), relies on the production and detection of compounds known as pheromones to elicit coordinated responses among members of a community. Pheromones produced by Gram-positive bacteria are comprised of small peptides. Based on both peptide structure and sensory system architectures, Gram-positive bacterial signaling pathways may be classified into one of four groups with a defining hallmark: cyclical peptides of the Agr type, peptides that contain Gly-Gly processing motifs, sensory systems of the RNPP family, or the recently characterized Rgg-like regulatory family. The recent discovery that Rgg family members respond to peptide pheromones increases substantially the number of species in which QS is likely a key regulatory component. These pathways control a variety of fundamental behaviors including conjugation, natural competence for transformation, biofilm development, and virulence factor regulation. Overlapping QS pathways found in multiple species and pathways that utilize conserved peptide pheromones provide opportunities for interspecies communication. Here we review pheromone signaling identified in the genera Enterococcus and Streptococcus, providing examples of all four types of pathways. PMID:24118108

  10. Enterococcus ureilyticus sp. nov. and Enterococcus rotai sp. nov., two urease-producing enterococci from the environment.

    PubMed

    Sedláček, Ivo; Holochová, Pavla; Mašlaňová, Ivana; Kosina, Marcel; Spröer, Cathrin; Bryndová, Hana; Vandamme, Peter; Rudolf, Ivo; Hubálek, Zdenek; Švec, Pavel

    2013-02-01

    A set of 25 urease-producing, yellow-pigmented enterococci was isolated from environmental sources. Phenotypic classification divided the isolates into two phena. Both phena were characterized using 16S rRNA gene sequence analysis, DNA base composition, rep-PCR fingerprinting and automated ribotyping. The obtained data distinguished the isolates from all members of the genus Enterococcus with validly published names and placed them in the Enterococcus faecalis species group. DNA-DNA hybridization experiments, pheS and rpoA sequencing and whole-cell protein electrophoresis provided conclusive evidence for the classification of each phenon as a novel species of the genus Enterococcus, for which the names Enterococcus ureilyticus sp. nov. (type strain CCM 4629(T)  = LMG 26676(T)  = CCUG 48799(T)), inhabiting water and plants, and Enterococcus rotai sp. nov. (type strain CCM 4630(T)  = LMG 26678(T)  = CCUG 61593(T)), inhabiting water, insects (mosquitoes) and plants, are proposed.

  11. The N-terminal domain of enterococcal surface protein, Esp, is sufficient for Esp-mediated biofilm enhancement in Enterococcus faecalis.

    PubMed

    Tendolkar, Preeti M; Baghdayan, Arto S; Shankar, Nathan

    2005-09-01

    Enterococci have emerged as one of the leading causes of nosocomial bloodstream, surgical site, and urinary tract infections. More recently, enterococci have been associated with biofilms, which are bacterial communities attached to a surface and encased in an extracellular polymeric matrix. The enterococcal cell surface-associated protein, Esp, enhances biofilm formation by Enterococcus faecalis in a glucose-dependent manner. Mature Esp consists of a nonrepeat N-terminal domain and a central region made up of two types of tandem repeats followed by a C-terminal membrane-spanning and anchor domain. This study was undertaken to localize the specific domain(s) of Esp that plays a role in Esp-mediated biofilm enhancement. To achieve this objective, we constructed in-frame deletion mutants expressing truncated forms of Esp in an isogenic background. By comparing strains expressing the mutant forms of Esp to those expressing wild-type Esp, we found that the strain expressing Esp lacking the N-terminal domain formed biofilms that were quantitatively less in biovolume than the strain expressing wild-type Esp. Furthermore, an E. faecalis strain expressing only the N-terminal domain of Esp fused to a heterologous protein anchor formed biofilms that were quantitatively similar to those formed by a strain expressing full-length Esp. This suggested that the minimal region contributing to Esp-mediated biofilm enhancement in E. faecalis was confined to the nonrepeat N-terminal domain. Expression of full-length E. faecalis Esp in heterologous host systems of esp-deficient Lactococcus lactis and Enterococcus faecium did not enhance biofilm formation as was observed for E. faecalis. These results suggest that Esp may require interaction with an additional E. faecalis-specific factor(s) to result in biofilm enhancement.

  12. Characterization of monolaurin resistance in Enterococcus faecalis.

    PubMed

    Dufour, Muriel; Manson, Janet M; Bremer, Philip J; Dufour, Jean-Pierre; Cook, Gregory M; Simmonds, Robin S

    2007-09-01

    There is increasing concern regarding the presence of vancomycin-resistant enterococci in domestically farmed animals, which may act as reservoirs and vehicles of transmission for drug-resistant enterococci to humans, resulting in serious infections. In order to assess the potential for the use of monolaurin as a food preservative, it is important to understand both its target and potential mechanisms of resistance. A Tn917 mutant library of Enterococcus faecalis AR01/DGVS was screened for resistance (MIC, >100 microg/ml) to monolaurin. Three mutants were identified as resistant to monolaurin and were designated DGRM2, DGRM5, and DGRM12. The gene interrupted in all three mutants was identified as traB, which encodes an E. faecalis pheromone shutdown protein and whose complementation in trans restored monolaurin sensitivity in all three mutants. DGRM2 was selected for further characterization. E. faecalis DGRM2 showed increased resistance to gentamicin and chloramphenicol (inhibitors of protein synthesis), while no difference in the MIC was observed with the cell wall-active antibiotics penicillin and vancomycin. E. faecalis AR01/DGVS and DGRM2 were shown to have similar rates (30% cell lysis after 4 h) of cell autolytic activity when activated by monolaurin. Differences in cell surface hydrophobicity were observed between the wild type and the mutant, with the cell surface of the parent strain being significantly more hydrophobic. Analysis of the cell wall structure of DGRM2 by transmission electron microscopy revealed an increase in the apparent cell wall thickness and contraction of its cytoplasm. Taken together, these results suggest that the increased resistance of DGRM2 was due to a change in cell surface hydrophobicity, consequently limiting the diffusion of monolaurin to a potential target in the cytoplasmic membrane and/or cytoplasm of E. faecalis.

  13. Enterococcus Species in the Oral Cavity: Prevalence, Virulence Factors and Antimicrobial Susceptibility

    PubMed Central

    Komiyama, Edson Yukio; Samaranayake, Lakshman P.; Parahitiyawa, Nipuna B.; Balducci, Ivan

    2016-01-01

    Enterococci are considered as transient constituent components of the oral microbiome that may cause a variety of oral and systemic infections. As there is sparse data on the oral enterococcal prevalence, we evaluated the Enterococcus spp. and their virulence attributes including antimicrobial resistance in a healthy Brazilian cohort. A total of 240 individuals in different age groups were studied (children 4–11 yrs, adolescents 12–17 yrs, young adults 18–29 yrs, adults 30–59 yrs, elderly over 60 yrs). Oral rinses were collected and isolates were identified by API 20 Strep and confirmed by 16S rDNA sequencing. E. faecalis isolates, in particular, were evaluated for virulence attributes such as their biofilm formation potential, and susceptibility to antimicrobials and an antiseptic, chlorhexidine gluconate. A total of 40 individuals (16.6%) and 10% children, 4% adolescents, 14% young adults, 30% adults, and 25% elderly carried oral enterococci. The oral enterococcal burden in adolescents was significantly lower than in the adults (p = 0.000) and elderly (p = 0.004). The proportion of carriers was higher among females (p = 0.001). E. faecalis was the most frequent isolate in all the age groups (p = 0.000), followed by E. durans and E. faecium. Whilst all the clinical isolates were able to form biofilms, only a proportion of them were able to produce lipase (92%), hemolysin (38%), and gelatinase (39%). Of all the isolates 53.8% were resistant to tetracycline, 12.3% to amoxicillin, 16.0% to ampicillin, 20.8% to chloramphenicol and 43.4% to erythromycin. None of the isolates were resistant to vancomycin. Our data suggest that in this Brazilian cohort the oral cavity may act as a significant reservoir of rather virulent and antibiotic resistant enterococci, with an increasing degree of carriage in the adults and elderly. Hence clinicians should be cognizant of this silent reservoir of virulent enterococci that may pose a particular threat of nosocomial infection

  14. [Emergency of vancomycin-resistant Enterococcus infections in a teaching hospital in Chile].

    PubMed

    Fica, Alberto; Jemenao, María Irene; Bilbao, Paola; Ruiz, Gloria; Sakurada, Andrea; Pérez de Arce, Edith; Zúñiga, Isabel; Gompertz, Macarena

    2007-12-01

    An active surveillance of vancomycin-resistant enterococci (VRE) intestinal colonization in selected group of patients has been developed in Chile since year 2000. Nevertheless, no reports of clinical cases have been published. Aim. To describe main clinical and microbiological features of patients infected by VRE in a tertiary-level teaching Hospital. Patients and methods. Intestinal and clinical samples positive to VRE were provided by laboratory, and a retrospective analysis of potential risk factors, clinical features, treatment and outcomes was performed. Study encompassed years 2001 to 2006. Main results. 23 cases of infections were identified, all cases occurring during 2005 and 2006. Incidence rate was 0.07 and 0.09 cases per 1000 occupied bed-days, respectively. The mean age was 62.0 +/- 17 years. A significant proportion of patients had cancer (39.1%), recent surgical procedures (54.1%), were on dialysis (26.1%), or were using steroids (26.1%). Most patients had received 2 or more antimicrobial (87%), almost a third represented transfers from other hospitals and an additional 22% readmissions before 30 days of latest discharge. Patients were mainly hospitalized in the ICU (60.9%) but nearly 30% were associated exclusively to nephrological or onco-hematological wards. Clinical manifestations included bacteremia (30.4%), surgical site infections or abscesses (26.1%), urinary tract infections (26.1%) and others. . Three patients (13%) did not have symptoms. After identification was possible, all isolates were identified as E. faecium (82.6% of total), the rest as Enterococcus sp. Most strains showed intermediate susceptibility to vancomycin (66.7%). For 14 strains studied both with vancomycin and teicoplanin, , phenotype Van B was predominant (85.7%), followed by VanA (7.1%) and VanB/VanD type (7.1%). No molecular studies were performed. Fifteen patients (65.4%) received a surgical and/or medical treatment. A favorable response was observed in 80% of these

  15. Multipartite asymmetric quantum cloning

    SciTech Connect

    Iblisdir, S.; Gisin, N.; Acin, A.; Cerf, N.J.; Filip, R.; Fiurasek, J.

    2005-10-15

    We investigate the optimal distribution of quantum information over multipartite systems in asymmetric settings. We introduce cloning transformations that take N identical replicas of a pure state in any dimension as input and yield a collection of clones with nonidentical fidelities. As an example, if the clones are partitioned into a set of M{sub A} clones with fidelity F{sup A} and another set of M{sub B} clones with fidelity F{sup B}, the trade-off between these fidelities is analyzed, and particular cases of optimal N{yields}M{sub A}+M{sub B} cloning machines are exhibited. We also present an optimal 1{yields}1+1+1 cloning machine, which is an example of a tripartite fully asymmetric cloner. Finally, it is shown how these cloning machines can be optically realized.

  16. Aristotle and headless clones.

    PubMed

    Mosteller, Timothy

    2005-01-01

    Cloned organisms can be genetically altered so that they do not exhibit higher brain functioning. This form of therapeutic cloning allows for genetically identical organs and tissues to be harvested from the clone for the use of the organism that is cloned. "Spare parts" cloning promises many opportunities for future medical advances. What is the ontological and ethical status of spare parts, headless clones? This paper attempts to answer this question from the perspective of Aristotle's view of the soul. Aristotle's metaphysics as applied to his view of biological essences generates an ethic that can contribute to moral reasoning regarding the use of headless spare parts clones. The task of this paper is to show the implications that Aristotle's view of the soul, if it is true, would have on the ethics of headless, spare parts cloning.

  17. Genetic detection and multilocus sequence typing of vanA-containing Enterococcus strains from mullets fish (Liza ramada).

    PubMed

    Araújo, Carlos; Torres, Carmen; Gonçalves, Alexandre; Carneiro, Catarina; López, Maria; Radhouani, Hajer; Pardal, Miguel; Igrejas, Gilberto; Poeta, Patrícia

    2011-09-01

    Enterococci have emerged as important nosocomial and community-acquired pathogens in humans. The presence of vanA-enterococci was investigated in 103 fecal samples recovered from mullets fish (Liza ramada). All fecal samples were inoculated in Slanetz-Bartley agar plates supplemented with 4 mg/L of vancomycin for vancomycin-resistant enterococci (VRE) recovery and two isolates/sample were characterized. Antibiotic susceptibility was tested for 11 antibiotics by disk diffusion and agar dilution methods. VRE identification was performed by biochemical and molecular methods. Additionally, the mechanisms of resistance to glycopeptides (vanA, vanB, vanC1, vanC2, and vanD) and other antibiotics [erm(A), erm(B), tet(L), tet(M), aph(2'')-aac(6'), aph(3')-IIIa, ant(6'), vat(D), vat(E)] as well as the presence of enterococcal surface protein (esp) and hyl virulence factors were investigated. vanA-Enterococcus faecium isolates were recovered from 4 of 103 tested samples, and they showed glycopeptide and erythromycin resistances. Three of them were also ampicillin resistant, two showed resistance to tetracycline, ciprofloxacin, and kanamycin, and one showed resistance to gentamicin. The tet(M) and erm(B) genes were found in all tetracycline- and erythromycin-resistant strains, respectively. The aph(3')-III and aph(2'')-aac(6') genes were identified in the kanamycin- and gentamicin-resistant isolates, respectively. The IS1216 element was identified within vanX-vanY region of Tn1546 in two vanA isolates. The hyl and esp virulence genes were found in four and two isolates, respectively. vanA-strains were ascribed to sequence types ST280 (two isolates) and ST273 (two isolates), including both lineages into the clonal complex CC17. Mullets fish can excrete VRE in their feces and may be a reservoir for such resistant bacteria that can be transmitted to other animals including humans.

  18. Animal Cloning and Food Safety

    MedlinePlus

    ... milk from clones of cattle, swine (pigs), and goats, and the offspring of clones from any species ... composition of food products from cattle, swine, and goat clones, or the offspring of any animal clones, ...

  19. Impact of probiotic drugs, based on Enterobacter faecium autostrains, on human intestinal microflora in confined habitat

    NASA Astrophysics Data System (ADS)

    Viacheslav, Ilyin; Batov, Alexey; Usanova, Nonna

    The aim of research: Investigation of influence of probiotic drugs based on autostrains of Enter-obacter faecium, selected from the crew in long term isolation experiment in confined habitat. It is known that during long-term presence in confined habitat the risk of infectious diseases increases. One of the main infectious risk occurs during first 20 days of isolation as a result of exchange of strains and stress-mediated disbacterioses. Therefore it is necessary to evaluate activities of probiotics to avoid this risk. Furthermore, in case of super long term autonomous flight there should be possibilities of application of autochthonous microflora strains as pro-biotics to strengthen colonial resistance of crews. Materials and methods: In the experiment there were used probiotic drugs based on autostrains of E. faecium, selected from the crew before the experiment. Probiotic drugs were consumed during 30 days since the beginning of the experiment with the break of consumption between 10th to 19th day. Results: Comparing the state of intestinal microflora of the crew on the baseline and 14th day of experiment re-vealed remarkable changes of microflora: the increasing of concentration of bifidobacteria and E. faecium (approximately 10 times), elimination of hemolytic streptococcus, yeasts, reduction of the rate of S.aureus, hemolytic gramnegative non-fermenting rods, lactobacilli and normal E.coli. On the 45th day of isolation, 15 days after finishing of auto-strains administration, there fere signs of restoration of disbacteriosis: the quantitative decreasing lactobacilli, bifidobacteria and normal E.coli, increasing of the rate of S.aureus, hemolytic gramnegative nonfermentive rods. Conclusion: Thus we managed to avoid risk of pathogenicity potential growth in first 2 decades of isolation. Application of probiotic, based on the autostrains of E. faecium leads to insignificant changes of concentration of lactobacteries, bifidobacteries, normal E. coli and to

  20. Genome Sequence of Enterococcus faecalis Strain CG_E.

    PubMed

    Gabris, Christina; Poehlein, Anja; Bengelsdorf, Frank R; Daniel, Rolf; Dürre, Peter

    2017-01-12

    Enterococcus faecalis CG_E is a Gram-positive, lactic acid-producing coccus. The draft genome of E. faecalis strain CG_E comprises 2,969,881 bp and exhibits a G+C content of 37.34%. The genome encodes 2,848 predicted protein-encoding and 97 RNA genes.

  1. Bacteriocin from Honeybee Beebread Enterococcus avium, Active against Listeria monocytogenes

    PubMed Central

    Audisio, M. Carina; Terzolo, Horacio R.; Apella, María C.

    2005-01-01

    Enterococcus avium isolated from Apis mellifera beebread produces a thermoresistant bacteriocin with a strain-dependent inhibitory effect on Listeria and without effect on gram-negative bacteria. The bacteriocin appeared to be a polypeptide of about 6 kDa. Genetic analyses revealed no extrachromosomal material in E. avium. PMID:15933045

  2. Survival of Escherichia coli and Enterococcus in Stream Water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    E. coli and Enterococcus indicate fecal contamination and are used for monitoring of lakes, streams, and rivers. Transport of bacteria from manured or pastured lands can result in large bacterial loads from both small and large runoff events and the persistence of bacteria following these loadings i...

  3. Enterococcus saccharolyticus subsp. taiwanensis subsp. nov., isolated from broccoli.

    PubMed

    Chen, Yi-sheng; Lin, Yu-hsuan; Pan, Shwu-fen; Ji, Si-hua; Chang, Yu-chung; Yu, Chi-rong; Liou, Min-shiuan; Wu, Hui-chung; Otoguro, Misa; Yanagida, Fujitoshi; Liao, Chen-chung; Chiu, Chi-ming; Huang, Bi-qiang

    2013-12-01

    A coccal strain isolated from fresh broccoli was initially identified as Enterococcus saccharolyticus; however, molecular identification and phenotypic traits did not support this identification. DNA-DNA hybridization with the type strain of E. saccharolyticus (76.4 % relatedness), DNA G+C content (35.7 mol%), phylogenetic analysis based on 16S rRNA, pheS and rpoA gene sequences, rep-PCR fingerprinting and profiles of cellular fatty acids, whole-cell proteins and enzyme activities, together with carbohydrate metabolism characteristics, indicated that this strain is distinct and represents a novel subspecies, for which the name Enterococcus saccharolyticus subsp. taiwanensis subsp. nov. is proposed. The type strain is 812(T) ( = NBRC 109476(T) = BCRC 80575(T)). Furthermore, we present an emended description of Enterococcus saccharolyticus and proposal of Enterococcus saccharolyticus subsp. saccharolyticus subsp. nov. (type strain ATCC 43076(T) = CCUG 27643(T) = CCUG 33311(T) = CIP 103246(T) = DSM 20726(T) = JCM 8734(T) = LMG 11427(T) = NBRC 100493(T) = NCIMB 702594(T)).

  4. An antimicrobial peptidoglycan hydrolase for treating Enterococcus faecalis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enterococcus faecalis is an intestinal bacteria species that can become an opportunistic pathogen in humans and farm animals with antibiotic resistant strains becoming increasingly common. In farm animals, strong antimicrobials, such as Vancomycin, should not be used due to the risk of propagation ...

  5. Enterococcus alcedinis sp. nov., isolated from common kingfisher (Alcedo atthis).

    PubMed

    Frolková, Petra; Švec, Pavel; Sedláček, Ivo; Mašlaňová, Ivana; Černohlávková, Jitka; Ghosh, Anuradha; Zurek, Ludek; Radiměřský, Tomáš; Literák, Ivan

    2013-08-01

    Two Gram-positive, catalase-negative bacterial strains were isolated from the cloaca of common kingfishers (Alcedo atthis). Repetitive sequence-based PCR fingerprinting using the (GTG)5 primer grouped these isolates into a single cluster separated from all known enterococcal species. The two strains revealed identical 16S rRNA gene sequences placing them within the genus Enterococcus with Enterococcus aquimarinus LMG 16607(T) as the closest relative (97.14 % similarity). Further taxonomic investigation using sequencing of the genes for the superoxide dismutase (sodA), phenylalanyl-tRNA synthase alpha subunit (pheS) and the RNA polymerase alpha subunit (rpoA) as well as application of whole-cell protein fingerprinting, automated ribotyping and extensive phenotyping confirmed that both strains belong to the same species. Based on data from this polyphasic study, these strains represent a novel species of the genus Enterococcus, for which the name Enterococcus alcedinis sp. nov. is proposed. The type strain is L34(T) (= CCM 8433(T) = LMG 27164(T)).

  6. Genome Sequence of Enterococcus faecalis Strain CG_E

    PubMed Central

    Gabris, Christina; Daniel, Rolf

    2017-01-01

    ABSTRACT Enterococcus faecalis CG_E is a Gram-positive, lactic acid-producing coccus. The draft genome of E. faecalis strain CG_E comprises 2,969,881 bp and exhibits a G+C content of 37.34%. The genome encodes 2,848 predicted protein-encoding and 97 RNA genes. PMID:28082508

  7. Fingerprinting of poultry isolates of Enterococcus cecorum using three molecular typing methods.

    PubMed

    Wijetunge, Dona Saumya; Dunn, Patricia; Wallner-Pendleton, Eva; Lintner, Valerie; Lu, Huaguang; Kariyawasam, Subhashinie

    2012-11-01

    Enterococcus cecorum is an emerging challenge to the broiler industry. The organism has been implicated in septicemia, spondylitis, arthritis, and osteomyelitis in commercial broilers and broiler breeders, which lead to economic losses attributed to increased mortality and culling rates, decreased average processing weights, and increased feed conversion ratios. The current study evaluated the genetic variability of 30 clinical isolates of E. cecorum from outbreaks in Pennsylvania, using 3 molecular typing methods, namely, pulsed-field gel electrophoresis (PFGE), randomly amplified polymorphic DNA analysis, and enterobacterial repetitive intergenic consensus-PCR (polymerase chain reaction), in order to understand their genetic relatedness and to identify possible pathogenic clones. The study revealed the existence of genotypic polymorphism among E. cecorum associated with clinical disease. Of the 3 typing methods used, PFGE analysis demonstrated higher genetic variability of E. cecorum isolates compared to PCR-based methods. Also, each molecular typing method was evaluated in terms of typeability, discriminatory power, and reproducibility for application of these typing methods in fingerprinting of E. cecorum in future reference. Pulsed-field gel electrophoresis provided the most reliable results with greater discriminatory power and higher reproducibility compared to the 2 PCR-based methods.

  8. Molecular epidemiology of Enterococcus cecorum isolates recovered from enterococcal spondylitis outbreaks in the southeastern United States.

    PubMed

    Borst, Luke B; Suyemoto, M Mitsu; Robbins, Kabel M; Lyman, Roberta L; Martin, Michael P; Barnes, H John

    2012-10-01

    Enterococcus cecorum, a normal intestinal inhabitant, is increasingly responsible for outbreaks of arthritis and osteomyelitis in chickens worldwide. Enterococcal spondylitis (ES) is a specific manifestation of E. cecorum-associated disease in which increased flock morbidity and mortality result from chronic infection involving the free thoracic vertebra. In this study the genetic relatedness and antimicrobial resistance of isolates recovered from ES-affected flocks in the southeastern United States were determined. ES outbreaks from 2007 to 2011 were investigated in North Carolina (15 flocks, 13 farms, four integrators), South Carolina (one flock, one farm, one integrator) and Alabama (six flocks, six farms, one integrator). From these 22 epidemiologically distinct outbreaks, 326 isolates of E. cecorum were recovered. Isolates from spinal lesions and caeca of affected birds (cases) and caeca of unaffected birds (controls) were genotyped using pulsed-field gel electrophoresis; phenotyped using both GenIII MicroPlate™ (Biolog; Hayward, CA, USA) microbial identification plates and antimicrobial sensitivity testing; and compared with each other. Isolates from spinal lesions were incapable of mannitol metabolism and the majority of these isolates were genetically clonal. In contrast, caecal isolates from control birds varied in their ability to metabolize mannitol and were genetically diverse. Isolates from both case and control birds had high levels of antimicrobial resistance. These findings indicate that the increase in E. cecorum-associated disease in the southeast United States is due to the emergence of new clones with increased pathogenicity and multidrug resistance.

  9. vanE gene cluster of vancomycin-resistant Enterococcus faecalis BM4405.

    PubMed

    Abadía Patiño, Lorena; Courvalin, Patrice; Perichon, Bruno

    2002-12-01

    Acquired VanE-type resistance to low levels of vancomycin (MIC = 16 microg/ml) in Enterococcus faecalis BM4405 is due to the inducible synthesis of peptidoglyean precursors terminating in D-alanine-D-serine (Fines,M., B. Prichon, P. Reynolds, D. Sahm, and P. Courvalin, Antimicrob. Agents Chemother. 43:2161-2164, 1999). A chromosomal location was assigned to the vanE operon by pulsed-field gel electrophoresis and hybridization, and its sequence was determined. Three genes, encoding the VanE ligase, the VanXYE DD-peptidase, and the VanTE serine racemase, that displayed 43 to 53% identity with the corresponding genes in the vanC operon were found. In addition, two genes coding for a two-component regulatory system, VanRE-VanSE, exhibiting 60 and 44% identity with VanR,-VanS, were present downstream from vanTE. However, because of a stop codon at position 78, VanSE was probably not functional. The five genes, with the same orientation, were shown to be cotranscribed by Northern analysis and reverse transcription-PCR. The vanE, vanXYE, and vanTE genes conferred inducible low-level resistance to vancomycin after cloning in E. faecalis JH2-2, probably following cross talk with a two-component regulatory system of the host.

  10. Enterococcus xiangfangensis sp. nov., isolated from Chinese pickle.

    PubMed

    Li, Chun Yan; Tian, Fen; Zhao, Ya Dong; Gu, Chun Tao

    2014-03-01

    A Gram-stain-positive bacterial strain, 11097(T), was isolated from traditional pickle in Heilongjiang Province, China. The bacterium was characterized using a polyphasic approach, including 16S rRNA gene sequence analysis, phenylalanyl-tRNA synthase (pheS) gene sequence analysis, RNA polymerase α subunit (rpoA) gene sequence analysis, fatty acid methyl ester (FAME) analysis, determination of DNA G+C content, DNA-DNA hybridization and an analysis of phenotypic features. Strain 11097(T) was phylogenetically related to Enterococcus devriesei, E. pseudoavium, E. viikkiensis, E. avium, E. malodoratus, E. gilvus and E. raffinosus. Strain 11097(T) had 99.1-99.9% 16S rRNA gene sequence similarities, 78.2-83.2% pheS gene sequence similarities and 93.8-96.6% rpoA gene sequence similarities with type strains of phylogenetically related species. Based upon polyphasic characterization data obtained in the present study, a novel species of the genus Enterococcus, Enterococcus xiangfangensis sp. nov., is proposed with the type strain 11097(T) ( = LMG 27495(T) = NCIMB 14834(T)).

  11. Enterococcus rivorum sp. nov., from water of pristine brooks.

    PubMed

    Niemi, R Maarit; Ollinkangas, Tuula; Paulin, Lars; Svec, Pavel; Vandamme, Peter; Karkman, Antti; Kosina, Marcel; Lindström, Kristina

    2012-09-01

    A significant number of Enterococcus strains from pristine waters of two brooks in Finland formed a distinct cluster on the basis of whole-cell protein fingerprinting by one-dimensional SDS-PAGE. The strains shared the following characteristics. Cells were ovoid, Gram-positive-staining and non-spore-forming, appearing singly or in pairs or chains. They were facultatively anaerobic and catalase-negative. Growth in broth containing 6.5 % NaCl or at 45 °C was weak or absent. Production of D antigen was variable. The strains tolerated 60 °C for 30 min, 40 % bile and tellurite, hydrolysed aesculin strongly and gelatin weakly, produced no acid from hippurate and did not reduce it, grew weakly at 10 °C, showed a strong reaction for the Voges-Proskauer test and produced acid from methyl α-d-glucoside, mannitol, sorbitol and sucrose, with weak or no production of acid from methyl α-d-mannoside, l-arabinose, gluconate and l-xylose. Several of the strains were selected for identification on the basis of sequencing of almost the whole 16S rRNA gene and partial atpA and pheS genes and of (GTG)(5)-PCR fingerprints. Partial atpA and pheS gene sequencing was also performed for those type strains of Enterococcus species without available sequences in the database. The pristine brook isolates formed a novel species, for which the name Enterococcus rivorum sp. nov. (type strain S299(T) = HAMBI 3055(T) = LMG 25899(T) = CCM 7986(T)) is proposed. On the basis of 16S rRNA gene sequence similarity, E. rivorum sp. nov. is related to the Enterococcus faecalis genogoup. It is distinguished from described Enterococcus species on the basis of 16S rRNA, atpA and pheS gene sequences and whole-cell protein and (GTG)(5)-PCR fingerprints. It is most closely related to E. faecalis, but DNA-DNA hybridization confirms it to represent a novel species.

  12. Two novel species Enterococcus lemanii sp. nov. and Enterococcus eurekensis sp. nov., isolated from a swine-manure storage pit.

    PubMed

    Cotta, Michael A; Whitehead, Terence R; Falsen, Enevold; Moore, Edward; Lawson, Paul A

    2013-01-01

    A polyphasic taxonomic study using morphological, biochemical, chemotaxonomic and molecular genetic methods was performed on six strains of unknown Gram-positive, nonspore-forming, facultative anaerobic coccus-shaped bacteria isolated from a swine-manure storage pit. On the basis of the 16S rRNA, RNA polymerase α-subunit (rpoA) and 60 kDa chaperonin (cpn60) gene sequence analyses, it was shown that all the isolates were enterococci but formed two separate lines of descent. Pairwise 16S rRNA gene sequence comparisons demonstrated that the two novel organisms were most closely related to each other (97.9 %) and to Enterococcus aquimarinus (97.8 %). Both organisms contained major amounts of C(16:0), C(16:1) ω7c, C(16:1) ω7c, and C(18:1) ω7c/12t/9t as the major cellular fatty acids. Based on biochemical, chemotaxonomic and phylogenetic evidence, the names Enterococcus lemanii sp. nov. (type strain PC32(T) = CCUG 61260(T) = NRRL B-59661(T)) PPC27A = CCUG 61369; PPC38 = CCUG 61261 [corrected] and Enterococcus eurekensis sp. nov. (type strain PC4B(T) = CCUG 61259(T) = NRRL B-59662(T)) PPC15 = CCUG 61368; PPC107 = CCUG 61372 [corrected] are proposed for these hitherto undescribed species.

  13. [Human cloning or cannibalism].

    PubMed

    Sokolowski, L M

    2001-01-01

    In this article I develop the idea presented in my previous work that human cloning would be of little practical use since almost any aim that one would like to attain by multiple cloning of a concrete man or a group of people, are unattainable or it might be achieved by easier, cheaper and more efficient traditional methods. For this reason cloning of a man is unlikely to occur on a larger scale and only few people will decide to clone themselves. In this sense no social effects of human cloning will be disastrous for the human population. Yet investigations in human genetics are very important since they may provide medical applications far more important than human cloning. It is argued that the main trend of modern medicine: organ transplantation from an alien donor, will become socially dangerous in near future since the number of donors will be drastically smaller than the number of potential patients waiting for transplantations. This in turn may cause social conflicts and a form of medical cannibalism may arise. These problems and conflicts will be avoided if organ transplantation from an alien donor is replaced by organ cloning, i.e. by transplanting an organ developed from the patient.

  14. On cloning human beings.

    PubMed

    de Melo-Martin, Inmaculada

    2002-06-01

    The purpose of this paper is to show that arguments for and against cloning fail to make their case because of one or both of the following reasons: 1) they take for granted customary beliefs and assumptions that are far from being unquestionable; 2) they tend to ignore the context in which human cloning is developed. I will analyze some of the assumptions underlying the main arguments that have been offered for and against cloning. Once these assumptions are critically analyzed, arguments both rejecting and supporting human cloning seem to lose weight. I will first briefly present the main arguments that have been proposed against cloning and I will argue that they fail to establish their case. In the next section I will evaluate some of the positive arguments that have been offered supporting such technology. This analysis will show that the case for cloning also fails. Finally, I will maintain that because critics and especially supporters of this technology neglect the context in which human cloning is developed and might be implemented, their arguments are far from compelling.

  15. Statement on Human Cloning

    MedlinePlus

    ... form Search American Association for the Advancement of Science Statement on Human Cloning Tweet The American Association for the Advancement of Science (AAAS) recognizes the intense debates within our society ...

  16. Do Managers Clone Themselves?

    ERIC Educational Resources Information Center

    Baron, Alma S.

    1981-01-01

    A recent questionnaire survey provides statistics on male managers' views of female managers. The author recommends that male managers break out of their cloning behavior and that the goal ought to be a plurality in management. (Author/WD)

  17. Twins: A cloning experience.

    PubMed

    Prainsack, Barbara; Spector, Tim D

    2006-11-01

    Drawing upon qualitative interviews with monozygotic (identical) twins sharing 100% of their genes, and with dizygotic (fraternal) twins and singletons as control groups, this paper explores what it means to be genetically identical. (The twins interviewed were from the TwinsUK register in London.) In the context of the ongoing debate on human reproductive cloning, it examines questions such as: To what extent do identical twins perceive their emotional and physical bond to be a result of their genetic makeup? What would they think if they had been deliberately created genetically identical? How would they feel about being genetically identical to a person who was born a few years earlier or later? First, our respondents ascribed no great significance to the role of genes in their understanding of what it means to be identical twins. Second, the opinion that human reproductive cloning would "interfere with nature", or "contradict God's will", was expressed by our respondents exclusively on the abstract level. The more our respondents were able to relate a particular invented cloning scenario to their own life-worlds, the lower the prevalence of the argument. Third, for all three groups of respondents, the scenario of having been born in one of the other groups was perceived as strange. Fourth, the aspect that our respondents disliked about cloning scenarios was the potential motives of the cloners. Without equating monozygotic twins directly with "clones", these results from "naturally" genetically identical individuals add a new dimension to what a future cloning situation could entail: The cloned person might possibly (a) perceive a close physical and emotional connection to the progenitor as a blessing; (b) suffer from preconceptions of people who regard physical likeness as a sign of incomplete individuality; and (c) perceive the idea of not having been born a clone of a particular person as unpleasant.

  18. Genetic analysis of a novel plasmid encoded durancin locus in Enterococcus durans 41D

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enterococcus durans is commonly found in the intestinal tract in humans and animals and several strains are known to produce bacteriocins. Durancin GL, a novel bacteriocin of Enterococcus durans 41D with antilisterial activity was isolated from artisanal cheese samples and its genetic determinants ...

  19. Comparison of the effect of monolaurin on the growth and survival of Enterococcus and Salmonella

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of monolaurin, a glyceride ester derivative of lauric acid, on the growth of Enterococcus sp. and Salmonella sp. was determined. Salmonella is considered one of the main pathogens in poultry industry, and Enterococcus is an important indicator of fecal contamination and an important cause...

  20. Alloreactive T cell clones.

    PubMed

    Fitch, F W

    1984-01-01

    T cell clones are useful models for studying lymphocyte function both at the level of the individual cell and in interacting systems. Murine cytolytic and non- cytolyic T cell clones have been obtained with relative ease, and the particular procedure used to derive and maintain T cell clones may influence profoundly the characteristics of the resulting cells. The method of choice depends on the specific question to be asked. Although some clones have characteristics that would have been expected on the basis of results observed with bulk cell populations, other clones have rather unexpected properties. Although most T cell clones appear to be either cytolytic or non-cytolytic, this distinction is not always absolute. A high proportion of both cytolytic and non-cytolytic T cell clones have dual reactivity. This is true for cells which by other criteria appear to be true clones. The frequency of such cells is high enough to suggest that most if not all T cells may have reactivity for more than one antigenic determinant or that antigenic determinants recognized by T cells are shared widely and unexpectedly. It is not clear whether one or two different antigen receptors account for such dual reactivity. The nature of the T cell receptor for antigen remains obscure. T cell clones, because of their homogeneous nature, should make it easier to answer these important immunological questions. Although it remains to be determined how many distinct molecules account for the numerous biological activities found in the culture supernatants from antigen-stimulated T cell clones, it is clear that these factors influence several different types of cells that are involved directly and indirectly in immune responses. IL-2 stimulates both cytolytic and non-cytolytic T cells to proliferate. BCSF causes polyclonal activation of B cells, and there may be other factors which influence B cell responses to antigenic stimulation. IL-3 apparently stimulates maturation of immature T cells

  1. Evaluation of Enterococcus spp. from rainbow trout (Oncorhynchus mykiss, Walbaum), feed, and rearing environment against fish pathogens.

    PubMed

    Araújo, Carlos; Muñoz-Atienza, Estefanía; Hernández, Pablo E; Herranz, Carmen; Cintas, Luis M; Igrejas, Gilberto; Poeta, Patrícia

    2015-04-01

    The use of lactic acid bacteria of aquatic origin as probiotics constitutes an alternative strategy to the antibiotic treatment for disease control in aquaculture. Enterococci are currently used as probiotics in human and animal health. In this study, we evaluated the safety of 64 enterococci isolated from rainbow trout (Oncorhynchus mykiss, Walbaum), feed and rearing environment, and their antimicrobial activity against 9 fish pathogens. The 64 enterococcal isolates were identified to the species level by polymerase chain reaction (PCR), using specific primers for the different enterococcal species, and confirmed by superoxide dismutase gene sequencing. Enterococcus faecium and E. hirae were the most common species (42.2 and 35.9%, respectively). A total of 48 isolates (75%) showed phenotypic resistance to at least 1 antibiotic determined by a disk-diffusion method, and 25 isolates (39.1%) harbored at least 1 antibiotic resistance gene [erm(B), tet(M), tet(S), tet(K), tet(L), tet(T), vanC2, and aad(E)], detected by PCR. One (1.6%) isolate produced gelatinase and none produced hemolysin, using a plate assay. The virulence genes gelE (46.9%), efaAfs (17.2%), agg (1.6%), and hyl (1.6%) were detected by PCR. A total of 48 isolates (75%) exerted antimicrobial activity against 1 or more of the tested fish pathogens, using a stab-on-agar test. From these isolates, 21 (43.8%) harbored at least 1 bacteriocin-encoding gene (entP, entL50A and entL50B, hirJM79, entSE-K4, entQ and entA), detected by PCR. None of the enterococci showed bile deconjugation and mucin degradation abilities. A total of 17 enterococcal isolates (26.6%) that did not harbor any antibiotic resistance or virulence factor were considered safe for application as probiotics, including 6 isolates (35.3%) that showed antimicrobial activity against at least 1 fish pathogen and harbored at least 1 bacteriocin-encoding gene. Rainbow trout, feed, and rearing environment constitute an appropriate source for the

  2. Bioprosthetic Aortic Valve Endocarditis in Association with Enterococcus durans

    PubMed Central

    Di Gioacchino, Lorena; Balestrini, Fabrizio

    2016-01-01

    Enterococci are common organisms associated with endocarditis, but infection by Enterococcus durans is very rare. To our knowledge, only 3 cases have been reported in the medical literature, and all 3 have involved native valves. Here we publish the first reported case (to our knowledge) of E. durans endocarditis in association with a bioprosthetic aortic valve. After the organism and its antibiotic susceptibility were identified, the 74-year-old male patient was treated successfully with teicoplanin and gentamicin, over a course of 6 weeks. PMID:27127436

  3. Erythromycin- and copper-resistant Enterococcus hirae from marine sediment and co-transfer of erm(B) and tcrB to human Enterococcus faecalis.

    PubMed

    Pasquaroli, Sonia; Di Cesare, Andrea; Vignaroli, Carla; Conti, Giulia; Citterio, Barbara; Biavasco, Francesca

    2014-09-01

    An erythromycin-, copper- and cadmium-resistant isolate of Enterococcus hirae from marine sediment was shown to harbor the plasmid pRE25 and to co-transfer erm(B) and tcrB to Enterococcus faecalis JH2-2. These data highlight the scope for antibiotic resistance selection by the marine environment through heavy metals and its possible involvement in antibiotic-resistant enterococcal infections.

  4. Characterizing Vancomycin-Resistant Enterococcus Strains with Various Mechanisms of Daptomycin Resistance Developed in an In Vitro Pharmacokinetic/Pharmacodynamic Model▿

    PubMed Central

    Steed, Molly E.; Vidaillac, Celine; Rose, Warren E.; Winterfield, Patricia; Kaatz, Glenn W.; Rybak, Michael J.

    2011-01-01

    Two daptomycin (DAP) regimens were evaluated in a pharmacokinetic/pharmacodynamic (PK/PD) model, and the mutants recovered were examined for changes in phenotypic characteristics. Three Enterococcus faecium strains (vancomycin-resistant Enterococcus [VRE] ATCC 51559, VRE 12311, and VRE SF 12047) were utilized in a 7-day, 1-compartment in vitro PK/PD model. The simulated dosing regimens were DAP at 6 mg/kg/day (free Cmax [fCmax] = 7.9 μg/ml, half-life [t1/2] = 8 h) and DAP at 10 mg/kg/day (fCmax = 13.17 μg/ml, t1/2 = 8 h). Samples were plated daily on Mueller-Hinton agar containing DAP at 16 μg/ml and 50 mg/liter Ca2+ to assess the emergence of DAP resistance. For each strain, the mutant with the highest DAP MIC was then evaluated for changes in relative surface charge, cell wall thickness, and cytoplasmic membrane depolarization induced by DAP. The initial DAP MICs were 4 μg/ml for all 3 strains. A dose-dependent response and regrowth were observed for DAP 6 mg/kg/day and DAP 10 mg/kg/day against all 3 strains. Mutants of VRE ATCC 51559 (MIC = 128 and 64 μg/ml) and VRE 12311 (MIC = 256 and 32 μg/ml) were recovered from the DAP 6 mg and DAP 10 mg regimen, respectively. For VRE SF 12047, a mutant (MIC = 64 μg/ml) was recovered from the DAP 6 mg model. All mutants displayed an increase in relative surface charge compared to those of their respective parent strains. The DAP-resistant mutants displayed a 43 to 58% increase in cell wall thickness (P < 0.0001), while DAP membrane depolarization decreased by 53 to 65% compared to that of the susceptible strains. VRE with DAP resistance displayed increased surface charge, increased cell wall thickness, and decreased depolarization induced by DAP, consistent with previous observations in Staphylococcus aureus with reduced DAP susceptibility. Further characterization of DAP-resistant VRE is warranted. PMID:21788457

  5. Inhibition of Listeria monocytogenes by Enterococcus mundtii isolated from soil.

    PubMed

    Bigwood, T; Hudson, J A; Cooney, J; McIntyre, L; Billington, C; Heinemann, J A; Wall, F

    2012-12-01

    Two bacterial isolates with inhibitory activity against Listeria monocytogenes and Enterococcus faecalis were obtained from soil. Genotypic and phenotypic characterization identified them as Enterococcus mundtii, a species whose ability to compete with L. monocytogenes is relatively unexplored compared to other members of the genus. The thermal stability of the inhibitory factor and its sensitivity to proteolytic enzymes indicate that it is most likely a bacteriocin. Both isolates grew at comparable rates to L. monocytogenes at 5 °C and 10 °C in vitro. One isolate killed L. monocytogenes when it reached concentrations of 10(6)-10(8) CFU ml(-1). Minimum inocula of 10(6) and 10(5) CFU ml(-1) of E. mundtii were required to reduce and maintain L. monocytogenes concentrations beneath the level of detection at 5 °C and 10 °C, respectively. In situ experiments at 5 °C showed that E. mundtii inhibited the growth of L. monocytogenes on vacuum-packed cold smoked salmon during its four week shelf life. E. mundtii could, therefore, control the growth of L. monocytogenes at low temperatures, indicating a potential application in controlling this pathogen in chilled foods. To control growth of Listeria, the concentration of E. mundtii needs to be high, but it is possible that a purified bacteriocin could be used to achieve the same effect.

  6. Eradication of Enterococcus faecalis Biofilms on Human Dentin

    PubMed Central

    Rosen, Eyal; Tsesis, Igor; Elbahary, Shlomo; Storzi, Nimrod; Kolodkin-Gal, Ilana

    2016-01-01

    Objectives: This work assesses different methods to interfere with Enterococcus faecalis biofilms formed on human dentin slabs. Methods: First, methods are presented that select for small molecule inhibitors of biofilm targets using multi-well polystyrene biofilm plates. Next, we establish methodologies to study and interfere with biofilm formation on a medically relevant model, whereby biofilms are grown on human root dentin slabs. Results: Non-conventional D-amino acid (D-Leucine) can efficiently disperse biofilms formed on dentin slabs without disturbing planktonic growth. Cation chelators interfere with biofilm formation on dentin slabs and polystyrene surfaces, and modestly impact planktonic growth. Strikingly, sodium hypochlorite, the treatment conventionally used to decontaminate infected root canal systems, was extremely toxic to planktonic bacteria, but did not eradicate biofilm cells. Instead, it induced a viable but non-culturable state in biofilm cells when grown on dentin slabs. Conclusion: Sodium hypochlorite may contribute to bacterial persistence. A combination of the methods described here can greatly contribute to the development of biofilm inhibitors and therapies to treat Enterococcus faecalis infections formed in the root canal system. PMID:28082955

  7. Extremal quantum cloning machines

    SciTech Connect

    Chiribella, G.; D'Ariano, G. M.; Perinotti, P.; Cerf, N.J.

    2005-10-15

    We investigate the problem of cloning a set of states that is invariant under the action of an irreducible group representation. We then characterize the cloners that are extremal in the convex set of group covariant cloning machines, among which one can restrict the search for optimal cloners. For a set of states that is invariant under the discrete Weyl-Heisenberg group, we show that all extremal cloners can be unitarily realized using the so-called double-Bell states, whence providing a general proof of the popular ansatz used in the literature for finding optimal cloners in a variety of settings. Our result can also be generalized to continuous-variable optimal cloning in infinite dimensions, where the covariance group is the customary Weyl-Heisenberg group of displacement000.

  8. Characterization of two N-acetyl muramoylhydrolases of Streptococcus faecium ATCC 9790

    SciTech Connect

    Dolinger, D.L.

    1988-01-01

    Purified muramidase-1 of S. faecium has been shown to contain a covalently attached nucleotide. The nucleotide was isolated and identified as 5-mercaptouridine monophosphate, and to occur as multiple monomeric substitutions on the polypeptide chain, via a phosphodiester bond. Exhaustive proteolytic hydrolysis of purified muramidase-1 yielded a peptide fragment consisting of 5-mercaptouridine, tyrosine, alanine, glycine, and leucine. A second peptidoglycan hydrolase (muramidase-2) has been purified to apparent homogeneity. The enzymatic activity has been shown to be consistent with that of a 3-1,4-N-acetylmuramoylhydrolase and differs in substrate specificity and possibility mechanism of hydrolysis from muramidase-1. Purified enzyme appears as two protein staining bands of molecular masses 125 and 75 kDa after sodium dodecylsulfate polyacrylamide gel ectrophoresis. Elution and renaturation of the protein bands showed that both proteins contain muramidase-2 activity. In addition both proteins have also been shown to specifically bind ({sup 14}C)penicillin G and been tentatively identified as penicillin binding proteins 1 and 5, respectively.

  9. Lipids and lipoteichoic acid of autolysis-defective Streptococcus faecium strains.

    PubMed

    Shungu, D L; Cornett, J B; Shockman, G D

    1980-06-01

    Two of four previously isolated autolysis-defective mutants of Streptococcus faecium (Streptococcus faecalis ATCC 9790) incorporated substantially more [14C]glycerol into lipids and lipoteichoic acid than did the parent strain. Consistent with increased accumulation of lipids and lipoteichoic acid, significantly higher levels of phosphorus were found in the corresponding fractions of the two mutant strains than in the wild type. Although the autolysis-defective mutant strains contained the same assortment of lipids as the wild type, the relative amount of [14C]glycerol incorporated into diphosphatidylglycerol increased, accompanied by a decreased fraction of phosphatidylglycerol. These results suggested that increased cellular content of two types of substances, acylated lipoteichoic acid and lipids (notably diphosphatidylglycerol), which previously had been shown to be potent inhibitors of the N-acetylmuramoylhydrolase of this species, contributed to the autolysis-defective phenotype of these mutants. Consistent with this interpretation are observations that (i) cerulenin inhibition of fatty acid synthesis increased the rates of benzylpenicillin-induced cellular lysis and that (ii) Triton X-100 or Zwittergent 3-14 treatment could reveal the presence of otherwise cryptic but substantial levels of the active form of the autolysin in cells of three of four mutants and of the proteinase-activable latent form in all four mutants.

  10. To clone alone: the United Nations' Human Cloning Declaration.

    PubMed

    Isasi, Rosario M; Annas, George J

    2006-01-01

    The United Nations labored for almost four years to create a treaty governing human cloning. In 2005 that effort was abandoned, and instead the United Nations' General Assembly adopted a "Declaration on Human Cloning".

  11. Antibiotic resistance, efflux pump genes and virulence determinants in Enterococcus spp. from surface water systems.

    PubMed

    Molale, L G; Bezuidenhout, Cornelius Carlos

    2016-11-01

    The aim of this study was to report on antibiotic susceptibility patterns as well as highlight the presence of efflux pump genes and virulence genetic determinants in Enterococcus spp. isolated from South African surface water systems. One hundred and twenty-four Enterococcus isolates consisting of seven species were identified. Antimicrobial susceptibility testing revealed a high percentage of isolates was resistant to β-lactams and vancomycin. Many were also resistant to other antibiotic groups. These isolates were screened by PCR, for the presence of four efflux pump genes (mefA, tetK, tetL and msrC). Efflux genes mefA and tetK were not detected in any of the Enterococcus spp. However, tetL and msrC were detected in 17 % of the Enterococcus spp. The presence of virulence factors in the Enterococcus spp. harbouring efflux pump genes was determined. Virulence determinants were detected in 86 % of the Enterococcus spp. harbouring efflux pump genes. Four (asa1, cylA, gel and hyl) of the five virulence factors were detected. The findings of this study have demonstrated that Enterococcus from South African surface water systems are resistant to multiple antibiotics, some of which are frequently used for therapy. Furthermore, these isolates harbour efflux pump genes coding for resistance to antibiotics and virulence factors which enhance their pathogenic potential.

  12. Secure the Clones

    NASA Astrophysics Data System (ADS)

    Jensen, Thomas; Kirchner, Florent; Pichardie, David

    Exchanging mutable data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an internal mutable object. However, implementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a malicious sub-class. Currently no language-based mechanism supports secure object cloning. This paper proposes a type-based annotation system for defining modular copy policies for class-based object-oriented programs. A copy policy specifies the maximally allowed sharing between an object and its clone. We present a static enforcement mechanism that will guarantee that all classes fulfill their copy policy, even in the presence of overriding of copy methods, and establish the semantic correctness of the overall approach in Coq. The mechanism has been implemented and experimentally evaluated on clone methods from several Java libraries.

  13. Applications of quantum cloning

    NASA Astrophysics Data System (ADS)

    Pomarico, E.; Sanguinetti, B.; Sekatski, P.; Zbinden, H.; Gisin, N.

    2011-10-01

    Quantum Cloning Machines (QCMs) allow for the copying of information, within the limits imposed by quantum mechanics. These devices are particularly interesting in the high-gain regime, i.e., when one input qubit generates a state of many output qubits. In this regime, they allow for the study of certain aspects of the quantum to classical transition. The understanding of these aspects is the root of the two recent applications that we will review in this paper: the first one is the Quantum Cloning Radiometer, a device which is able to produce an absolute measure of spectral radiance. This device exploits the fact that in the quantum regime information can be copied with only finite fidelity, whereas when a state becomes macroscopic, this fidelity gradually increases to 1. Measuring the fidelity of the cloning operation then allows to precisely determine the absolute spectral radiance of the input optical source. We will then discuss whether a Quantum Cloning Machine could be used to produce a state visible by the naked human eye, and the possibility of a Bell Experiment with humans playing the role of detectors.

  14. The Cloning of America.

    ERIC Educational Resources Information Center

    Dobson, Judith E.; Dobson, Russell L.

    1981-01-01

    Proposes that the U.S. school system purports to prize human variability, but many educators are engaged in activities that seek to homogenize students. Describes these activities, including diagnosis, labeling, ability grouping, and positive reinforcement. Presents suggestions for counselors to combat sources of cloning and self-validation. (RC)

  15. Prevalence and phenotypic characterization of Enterococcus spp. isolated from food in Brazil

    PubMed Central

    Camargo, Carlos Henrique; Bruder-Nascimento, Ariane; Lee, Sarah Hwa In; Júnior, Ary Fernandes; Kaneno, Ramon; Rall, Vera Lúcia Mores

    2014-01-01

    We evaluated the frequency of enterococci from food and found 95.2% of positivity, being E. faecium and E. faecalis the most frequent species. High-level streptomycin resistance was observed, as well as gelatinase and hemolysis activity, showing the potential role of environmental strains as reservoir of virulence and resistance traits. PMID:24948921

  16. The First Human Cloned Embryo.

    ERIC Educational Resources Information Center

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  17. [Nuclear transfer and therapeutic cloning].

    PubMed

    Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

    2005-03-01

    Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

  18. Sequential cloning of chromosomes

    SciTech Connect

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  19. Water relations of populus clones

    SciTech Connect

    Pallardy, S.G.; Kozlowski, T.T.

    1981-02-01

    Stomatal aperture and water balance in the field of eight Populus clones varying in growth rate were closely related to environmental factors and clonal differences were clearly expressed. Leaf water potential (psi) was influenced by solar radiation, leaf conductance, evaporative demand, and soil moisture content. The effects of soil moisture on psi were greatly modified by atmospheric conditions and stomatal conductance. Several slow-growing clones exhibited extended periods of psi below that of rapidly growing clones, despite high evaporative demand and the much greater transpiring surfaces of the fast-growing clones. Stomata of all clones responded to changes in light intensity and vapor pressure gradient (VPG). Pronounced stomatal sensitivity to VPG of two rapidly growing clones of common parentage, and the resultant capacity of these clones to moderate water deficits under high evaporative demand, were associated with drought resistance in one of the parents. Seasonal maximum leaf conductance was positively related to growth in several clones, suggesting that rapidly growing clones possess the capacity to carry on higher rates of gas exchange under favorable conditions. Analysis of changes in psi with changes in transpirational flux density (TFD) showed that for four clones, psi change per unit change in TFD decreased as TFD increased, indicating plant adaptation for prevention of damaging psi even at high TFD. More rapidly growing clones exhibited a larger initial rate of decline in psi with TFD, but reduced the rate of decline more than slow-growing clones as TFD increased. (Refs. 41).

  20. Cloning Components of Human Telomerase.

    DTIC Science & Technology

    1998-07-01

    nuclear factor NF90 homolog. (5 clones). RNA binding protein. Poorly understood. 3. FRG1 . Poorly understood. 4. DEK. Weak homology to Tetrahymena p95...least some of the clones for poorly understood genes (e.g. Hax-1, FRG1 , NF90, NF45, KIAA0098, KIAA0026, BAC397c4). Aim II. Functional Cloning of the

  1. Enterococcus species diversity and molecular characterization of biomarker genes in Enterococcus faecalis in Port Blair Bay, Andaman and Nicobar Islands, India.

    PubMed

    Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Raghavan, Rangamaran Vijaya; Jha, Dilip Kumar; Venkateshwaran, Pitchiah; Das, Apurba Kumar; Dheenan, Palaiya Sukumaran; Vinithkumar, Nambali Valsalan; Dharani, Gopal; Kirubagaran, Ramalingam

    2015-05-15

    This study was performed to evaluate the abundance and diversity of Enterococcus sp. and the distribution of biomarker genes in Enterococcus faecalis in Port Blair Bay, Andaman and Nicobar Islands. The Enterococcus sp. densities at the seven sampling stations were highly influenced by tidal fluctuations and season. The distributions and diversities of species varied in the inner and outer regions of Port Blair Bay. Among the 1816 total isolates, the occurrence of fecal Enterococcus was high (1.78×10(4) CFU/100 mL) in Phoenix Bay. Moreover, 67.76% of the isolates were identified as Enterococcus, and the most frequently identified species were E. hirae, E. avium and E. faecalis. Assessments of antibiotic resistance and biomarker genes revealed the maximum occurrence in the Aberdeen Bay isolates. The most prevalent biomarker genes observed in the E. faecalis isolates were gelE and asa1, whereas cyl was not found among the isolates. In silico sequence analysis of biomarker genes of E. faecalis also revealed that they are evolutionarily well conserved with those of earlier reports. Further, multivariate analysis distinguished the JB, PB and OS stations from the other stations according to distinctive microbial densities and compositions. In addition, the Shannon-Wiener diversity indices and box-whisker plots further facilitated and supported the multivariate results.

  2. Emphysematous pyometra secondary to Enterococcus avium infection in a dog.

    PubMed

    Chang, An-Chi; Cheng, Ching-Chang; Wang, Hsien-Chi; Lee, Wei-Ming; Shyu, Ching-Lin; Lin, Cheng-Chung; Chen, Kuan-Sheng

    2016-06-16

    A 5-year-old female intact Mastiff dog was presented with a history of vaginal discharge for 1 day. Physical examination revealed a sanguineo-purulent vaginal discharge and systemic inflammatory response syndrome. Abdominal radiographs showed several dilated and gas- filled tubular loops. The differential diagnoses included emphysematous pyometra or small intestinal mechanical ileus. Surgical exploration of the abdomen demonstrated a severely dilated and gas-filled uterus, and emphysematous pyometra was confirmed. The patient's clinical signs resolved after ovariohysterectomy. Histopathology revealed mild endometrial cystic hyperplasia with infiltration of inflammatory cells in the superficial endometrial epithelia. Enterococcus avium, an α-hemolytic gram-positive coccus, was isolated from the uterus. This paper highlights the radiographic features of emphysematous pyometra and a pathogen that has never been reported to be associated with canine pyometra previously.

  3. In vitro susceptibility studies of vancomycin-resistant Enterococcus faecalis.

    PubMed Central

    Sahm, D F; Kissinger, J; Gilmore, M S; Murray, P R; Mulder, R; Solliday, J; Clarke, B

    1989-01-01

    Vancomycin resistance exhibited by Enterococcus faecalis isolates V583, V586, and V587 is described. The vancomycin MICs ranged from 32 to 64 micrograms/ml. Although resistant to vancomycin, the isolates were susceptible to teicoplanin (MIC, less than or equal to 0.5 micrograms/ml). Such a glycopeptide susceptibility profile has not been previously described for E. faecalis. Time kill studies showed that vancomycin resistance adversely affected the synergistic activity that vancomycin and aminoglycoside combinations usually demonstrate against enterococci. However, the ability to detect vancomycin resistance varied with the susceptibility testing method used. Whereas broth microdilution, broth macrodilution, and agar dilution methods detected resistance, disk-agar diffusion and the AutoMicrobic system Gram-Positive GPS-A susceptibility card (Vitek Systems Inc., Hazelwood, Mo.) did not. To detect vancomycin resistance reliably and establish the incidence of such E. faecalis isolates, adjustments in some susceptibility testing methods may be necessary. PMID:2554802

  4. Candida albicans and Enterococcus faecalis in the gut

    PubMed Central

    Garsin, Danielle A; Lorenz, Michael C

    2013-01-01

    The fungus Candida albicans and the gram-positive bacterium Enterococcus faecalis are both normal residents of the human gut microbiome and cause opportunistic disseminated infections in immunocompromised individuals. Using a nematode infection model, we recently showed that co-infection resulted in less pathology and less mortality than infection with either species alone and this was partly explained by an interkingdom signaling event in which a bacterial-derived product inhibits hyphal morphogenesis of C. albicans. In this addendum we discuss these findings in the contest of other described bacterial-fungal interactions and recent data suggesting a potentially synergistic relationship between these two species in the mouse gut as well. We suggest that E. faecalis and C. albicans promote a mutually beneficial association with the host, in effect choosing a commensal lifestyle over a pathogenic one. PMID:23941906

  5. In vitro activity of Amazon plant extracts against Enterococcus faecalis

    PubMed Central

    de Castilho, Adriana Lígia; da Silva, Juliana Paola Correa; Saraceni, Cintia Helena Coury; Díaz, Ingrit Elida Collantes; Paciencia, Mateus Luís Barradas; Varella, Antonio Drauzio; Suffredini, Ivana Barbosa

    2014-01-01

    Previous studies analyzing 2,200 plant extracts indicated anti-enterococcal activity in 25 extracts obtained from Brazilian forests’ plants. In the present study, these extracts were subjected to microdilution broth assay (MDBA) and disk diffusion assay (DDA) using planktonic Enterococcus faecalis ATCC® 29212™ and were submitted to phytochemical analysis in TLC and HPLC. Three extracts obtained from Ipomoea alba (MIC < 40 μg/mL), Diclinanona calycina (MIC ≤ 40 μg/mL) and Moronobea coccinea (40 < MIC < 80 μg/mL; MBC = 80 μg/mL) showed significant bactericidal activity in the MDBA and four extracts obtained from I. alba (14.04 ± 0.55 mm diameter) S. globulifera (14.43 ± 0.33 mm and 12.18 ± 0.28 mm diameter) and Connarus ruber var. ruber (13.13 ± 0.18 mm diameter) were active in DDA. Residues H2O obtained from Psidium densicomum (mean of 16.78 mm diameter) and from Stryphnodendron pulcherrimum (mean of 15.97 mm diameter) have shown an improved antibacterial activity after fractionation if compared to that obtained from the respective crude extracts. Antioxidant activity was observed in some residues of the active extracts. TLC analysis showed that phenolic compounds are likely to be found in active extracts. Three molecules were isolated from S. globulifera and were identified by 13C NMR lupeol, α-amyrin and 3β-hydroxyglutin-5-ene. The present chemical and biological findings suggest that these extracts are a potential source of new anti-Enterococcus compounds to be introduced in endodontic therapy. PMID:25477906

  6. Three concepts of cloning in human beings.

    PubMed

    Cui, Ke-Hui

    2005-07-01

    Human cloning, organ cloning and tissue cloning are various types of cloning that occur at different levels with different methodologies. According to three standards of terminology for an embryo (fertilization through germ cells, development in the uterus and having the potential to produce a human life), tissue cloning and type I organ cloning will not produce an embryo. In contrast, human cloning and type II organ cloning will produce an embryo. Thus, only non-germinal tissue cloning and type I organ cloning are beyond the ethical question and will not change human beings as a species. Using cloned tissues to make new tissues or organs is promising for the future of medicine.

  7. Antimicrobial resistance and virulence of Enterococcus faecalis isolated from retail food

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although enterococci are considered opportunistic nosocomial pathogens, their contribution to food-borne illnesses via dissemination through retail food remains undefined. In this study, prevalence and association of antimicrobial resistance and virulence factors of 80 Enterococcus faecalis isolate...

  8. Draft Genome Sequence of an Enterococcus faecalis ATCC 19433 Siphovirus Isolated from Raw Domestic Sewage

    PubMed Central

    Ly, Melissa; Pride, David T.; Toranzos, Gary A.

    2017-01-01

    ABSTRACT We previously isolated and characterized an Enterococcus faecalis ATCC 19433 siphovirus from raw domestic sewage as a viral indicator of human fecal pollution. Here, we report the draft genome sequence of this bacteriophage. PMID:28104647

  9. Draft Genome Sequence of an Enterococcus faecalis ATCC 19433 Siphovirus Isolated from Raw Domestic Sewage.

    PubMed

    Santiago-Rodriguez, Tasha M; Ly, Melissa; Pride, David T; Toranzos, Gary A

    2017-01-19

    We previously isolated and characterized an Enterococcus faecalis ATCC 19433 siphovirus from raw domestic sewage as a viral indicator of human fecal pollution. Here, we report the draft genome sequence of this bacteriophage.

  10. Purification and characterization of enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4.

    PubMed Central

    Joosten, H M; Nunez, M; Devreese, B; Van Beeumen, J; Marugg, J D

    1996-01-01

    A simple two-step procedure was developed to obtain pure enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4. Chemical and genetic characterization revealed that the primary structure of enterocin 4 is identical to that of peptide antibiotic AS-48 from Enterococcus faecalis S-48. In contrast to the reported inhibitory spectrum of AS-48, enterocin 4 displayed no activity against gram-negative bacteria. PMID:8900014

  11. Probabilistic cloning of equidistant states

    SciTech Connect

    Jimenez, O.; Roa, Luis; Delgado, A.

    2010-08-15

    We study the probabilistic cloning of equidistant states. These states are such that the inner product between them is a complex constant or its conjugate. Thereby, it is possible to study their cloning in a simple way. In particular, we are interested in the behavior of the cloning probability as a function of the phase of the overlap among the involved states. We show that for certain families of equidistant states Duan and Guo's cloning machine leads to cloning probabilities lower than the optimal unambiguous discrimination probability of equidistant states. We propose an alternative cloning machine whose cloning probability is higher than or equal to the optimal unambiguous discrimination probability for any family of equidistant states. Both machines achieve the same probability for equidistant states whose inner product is a positive real number.

  12. Sequential cloning of chromosomes

    DOEpatents

    Lacks, Sanford A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism's chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (class IIS) enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes.

  13. Sequential cloning of chromosomes

    DOEpatents

    Lacks, S.A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (cla