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

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Soheili S

2015-05-01

Full Text Available Sara Soheili,1 Sobhan Ghafourian,2 Zamberi Sekawi,1 Vasantha Kumari Neela,1 Nourkhoda Sadeghifard,2 Morovat Taherikalani,2 Afra Khosravi,2 Ramliza Ramli,3 Rukman Awang Hamat11Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health sciences, Universiti Putra Malaysia, Serdang, Malaysia; 2Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran; 3Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaakob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia Abstract: 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

Enterococcus faecium and Enterococcus durans isolated from cheese: Survival in the presence of medications under simulated gastrointestinal conditions and adhesion properties.

Science.gov (United States)

Amaral, Daniel M F; Silva, Luana F; Casarotti, Sabrina N; Nascimento, Liane Caroline Sousa; Penna, Ana Lúcia B

2017-02-01

In this study, we evaluated the survival of Enterococcus faecium and Enterococcus durans, isolated from cheese, in the presence of medications and under simulated in vitro gastrointestinal conditions. The presence of genes encoding virulence factors, the susceptibility to antimicrobial agents, and adhesion properties were also assessed. Enterococcus faecium and E. durans both exhibited resistance to most of the tested medications but showed a large sensitivity to analgesics and antihypertensives; they also showed wide susceptibility to antimicrobial agents. Enterococcus durans SJRP29 had greater resistance to the presence of medications in comparison with the probiotic Lactobacillus acidophilus La-5. The strains, except for E. durans SJRP05, did not harbor virulence genes. Enterococcus durans SJRP14, SJRP17, and SJRP26 were sensitive to all tested antimicrobial agents. Enterococcus faecium was more stable during the simulation of gastrointestinal tract and showed greater viability. At the end of the assay, except for E. durans SJRP17, all strains showed high viability (>7 log cfu/mL). Enterococcus durans SJRP29 stood out from the other strains and was selected for further evaluation; it tolerated up to 3.0% NaCl at 30 and 37°C, besides having good adhesion properties (high values of auto-aggregation, co-aggregation, and hydrophobicity). Additionally, the microorganism did not show bile salt hydrolase activity or mucin degradation. These results encourage carrying out additional tests to evaluate the probiotic features by using in vitro dynamic models and in vivo tests before applying these strains to a food system. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Lactobacillus rhamnosus GG Outcompetes Enterococcus faecium via Mucus-Binding Pili

NARCIS (Netherlands)

Tytgat, Hanne L.P.; Douillard, François P.; Reunanen, Justus; Rasinkangas, Pia; Hendrickx, Antoni P.A.; Laine, Pia K.; Paulin, Lars; Satokari, Reetta; Vos, de Willem M.

2016-01-01

Vancomycin-resistant enterococci (VRE) have become a major nosocomial threat. Enterococcus faecium is of special concern, as it can easily acquire new antibiotic resistances and is an excellent colonizer of the human intestinal tract. Several clinical studies have explored the potential use of

Success of linezolid therapy for postneurosurgical ventriculitis due to vancomycin-resistant Enterococcus faecium: case report and literature review

Institute of Scientific and Technical Information of China (English)

JiaJi Qiu; Jie Tang; DeLing Li

2016-01-01

Background:Vancomycin-resistant Enterococcus faecium ventriculitis is one of the most severe events in postneurosurgical intracranial infections.There are no guidelines recommending an appropriate treatment before.Case presentation:This case presents a successful linezolid treatment for post-neurosurgical vancomycin-resistant Enterococcus faecium ventriculitis of a 24-year-old man in the department of neurosurgery,Beijing Tiantan Hospital.Conclusions:Linezolid should be considered as one of the important methods for the treatment of postneurosurgical intracranial infections caused by vancomycin-resistant Enterococcus.

Enterocin P Selectively Dissipates the Membrane Potential of Enterococcus faecium T136

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Herranz, C.; Chen, Y.; Chung, H.-J.; Cintas, L. M.; Hernández, P. E.; Montville, T. J.; Chikindas, M. L.

2001-01-01

Enterocin P is a pediocin-like, broad-spectrum bacteriocin which displays a strong inhibitory activity against Listeria monocytogenes. The bacteriocin was purified from the culture supernatant of Enterococcus faecium P13, and its molecular mechanism of action against the sensitive strain E. faecium T136 was evaluated. Although enterocin P caused significant reduction of the membrane potential (ΔΨ) and the intracellular ATP pool of the indicator organism, the pH gradient (ΔpH) component of the proton motive force (Δp) was not dissipated. By contrast, enterocin P caused carboxyfluorescein efflux from E. faecium T136-derived liposomes. PMID:11282622

Enterocin P Causes Potassium Ion Efflux from Enterococcus faecium T136 Cells

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Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.; Moll, Gert N.; Driessen, Arnold J. M.

2001-01-01

Enterocin P is a bacteriocin produced by Enterococcus faecium P13. We studied the mechanism of its bactericidal action using enterocin-P-sensitive E. faecium T136 cells. The bacteriocin is incapable of dissipating the transmembrane pH gradient. On the other hand, depending on the buffer used, enterocin P dissipates the transmembrane potential. Enterocin P efficiently elicits efflux of potassium ions, but not of intracellularly accumulated anions like phosphate and glutamate. Taken together, t...

Glycopeptide resistance in Enterococcus faecium from broilers and pigs following discontinued use of avoparcin

DEFF Research Database (Denmark)

Bager, Flemming; Aarestrup, Frank Møller; Madsen, Mogens

1999-01-01

The use of the glycopeptide growth promoter avoparcin was discontinued in Denmark in 1995 following concerns that vancomycin-resistant Enterococcus faecium occurring as a result of its use could be transferred to humans via food. The present study is an analysis of results obtained by the continu......The use of the glycopeptide growth promoter avoparcin was discontinued in Denmark in 1995 following concerns that vancomycin-resistant Enterococcus faecium occurring as a result of its use could be transferred to humans via food. The present study is an analysis of results obtained...... by the continuous surveillance of an antimicrobial resistance in Denmark (DANMAP) with the aim of determining the effect of the ban on the occurrence of glycopeptide resistance among E, faecium isolated from broilers and pigs, Among isolates from broilers, the proportion that were resistant to glycopeptides has....... Alternatively, the results indicate that the different outcomes may result from different co-selection patterns in pigs and broilers. In pigs, the antimicrobials most commonly used favored co-selection of glycopeptide-resistant strains of E. faecium while in broilers the antimicrobials most widely used selected...

Distinct SagA from hospital-associated clade A1 Enterococcus faecium strains contributes to biofilm formation

NARCIS (Netherlands)

F.L. Paganelli; M. de Been; J.C. Braat (Johanna); T.A. Hoogenboezem (Thomas); C. Vink (Cornelis); J. Bayjanov; M.R.C. Rogers; J. Huebner; M.J.M. Bonten (Marc); R.J.L. Willems (Rob); H.L. Leavis

2015-01-01

textabstractEnterococcus 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

FACTORS AFFECTED DECARBOXYLATION ACTIVITY OF ENTEROCOCCUS FAECIUM ISOLATED FROM RABBIT

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František Buňka

2012-04-01

Full Text Available Normal 0 21 false false false SK JA X-NONE Biogenic amines (BA are basic nitrogenous compounds formed mainly by decarboxylation of amino acids. There are generated in course of microbial, vegetable and animal metabolisms. The aim of the study was to monitor factors affected production of biogenic amines by Enterococcus faecium, which is found in rabbit meat. Biogenic amines were analyzed by means of UPLC (ultrahigh performance liquid chromatography equipped with a UV/VIS DAD detector. Decarboxylation activity of E. faecium was mainly influenced by the cultivation temperature and the amount of NaCl in this study. E. faecium produced most of the monitored biogenic amines levels: tyramine ˂2500 mg.l-1; putrescine ˂30 mg.l-1; spermidine ˂10 mg.l-1 and cadaverine ˂5 mg.l-1.doi:10.5219/182

Effect of Enterococcus faecium M74 strain on egg yolk fat and cholesterol

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Mária Angelovičová

2013-05-01

Full Text Available Abstract The aim was to evaluate the functional efficiency of a probiotic strain Enterococcus faecium M74 in the feed on egg yolk weight, egg yolk fat and cholesterol contents of Shaver Starcross 288 hens.  Feed in the experimental group was enriched with a probiotic additive containing of 5*109 viable Enterococcus faecium per g. Egg samples a total 30 pcs per group were collected during the first egg-laying period at week 28 and 38 of hens´ age. Non-significantly lower of egg yolk weight was observed in the experimental group at all sampling times compared with their respective controls. Non-significantly lower of egg yolk weight was observed in the experimental group at all sampling times compared with their respective controls. Significantly lower concentrations of egg yolk cholesterol were found in the experimental group at week 28, and week 38 in compare with controls. In conclusion, the addition of probiotic strains Enterococcus faecium M74 to the feed of Shaver Starcross 288 hens reduced cholesterol in egg yolk at all sampling times. Even though the hypocholesterolemic mechanism of probiotics has not yet been fully understood, it is an established fact that cholesterol and bile salt metabolism are closely linked. However, the hypocholesterolemic mechanism of probiotics based on the bile salt hydrolase activity hypothesis has not yet been sufficiently elucidated.

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

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Tu Hoang Khue Nguyen

2015-01-01

Full Text Available 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.

Dogs are a reservoir of ampicillin-resistant Enterococcus faecium lineages associated with human infections

DEFF Research Database (Denmark)

Damborg, Peter Panduro; Top, Janetta; Hendrickx, Antoni P.A.

2009-01-01

Ampicillin resistance is a marker for hospital-associated Enterococcus faecium. Feces from 208 dogs were selectively screened for the occurrence of ampicillin-resistant E. faecium (AREF). AREF was detected in 42 (23%) of 183 dogs screened in a cross-sectional study in the United Kingdom and in 19...

Characterization of an anti-listerial enterocin from wheat silage based Enterococcus faecium.

Science.gov (United States)

Bal, Emel Banu Buyukunal; Isevi, Taner; Bal, Mehmet Ali

2012-10-01

Two Enterococcus faecium and one E. faecalis strains isolated and identified from wheat silage were characterized based on plasmid content, hemolytic activity, antibiotic resistance patterns, bacteriocin production potential, and presence of enterocin structural genes (entA, entB, entP, entL50B). Among the isolates, only the E. faecium U7 strain exhibited bacteriocin activity against Listeria monocytogenes ATCC 7644, and vancomycin resistant Enterococcus spp. (VRE). A combination of three structural genes (entA, entB, and entP) was detected in E. faecium U7. A relationship between the presence of enterocin structural genes, and bacteriocin activity was detected in E. faecium U7; therefore partially purified enterocin (PPE) was further investigated from the isolate. Several bands of different molecular weights were expressed from PPE extracts following tricine SDS-PAGE analysis. However, the only band showing bacteriocin activity was in an approximate 4-kDa region. PPE treatment with proteinase K, lysozyme, and α -amylase caused complete loss of bacteriocin activity. PPE heat treatment at various temperatures resulted in a notable reduction in bacteriocin expression. Enterocin U7 was relatively heat stable, and presumably exhibits a glucoprotein nature with distinct inhibitory properties. Specific bacterial inhibitory activity of enterocin U7, and the producer strain absence of β -hemolysis and vancomycin susceptibility features deserves further investigation to evaluate its potential application in silage inoculation and food preservation. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enterocin P Causes Potassium Ion Efflux from Enterococcus faecium T136 Cells

Science.gov (United States)

Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.; Moll, Gert N.; Driessen, Arnold J. M.

2001-01-01

Enterocin P is a bacteriocin produced by Enterococcus faecium P13. We studied the mechanism of its bactericidal action using enterocin-P-sensitive E. faecium T136 cells. The bacteriocin is incapable of dissipating the transmembrane pH gradient. On the other hand, depending on the buffer used, enterocin P dissipates the transmembrane potential. Enterocin P efficiently elicits efflux of potassium ions, but not of intracellularly accumulated anions like phosphate and glutamate. Taken together, these data demonstrate that enterocin P forms specific, potassium ion-conducting pores in the cytoplasmic membrane of target cells. PMID:11181377

Simple test of synergy between ampicillin and vancomycin for resistant strains of Enterococcus faecium.

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Green, M; Barbadora, K; Wadowsky, R M

1994-01-01

The combination of ampicillin and vancomycin kills some but not all strains of ampicillin- and vancomycin-resistant Enterococcus faecium. We compared a simple test for synergy utilizing a commercially available microdilution susceptibility system with time-kill studies and determined acceptable breakpoints for this test for 20 strains of ampicillin- and vancomycin-resistant E. faecium. The combination of ampicillin and vancomycin was tested for synergy by time-kill, broth macrodilution, and b...

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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. PMID:26005332

Incidence of high-level evernimicin resistance in Enterococcus faecium among food animals and humans

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; McNicholas, P. M.

2002-01-01

Six high-level evernimicin-resistant Enterococcus faecium isolates were identified among 304 avilarnycin-resistant E. faecium isolates from animals and 404 stool samples from humans with diarrhea. All four animal isolates, and one of the human isolates, were able to transfer resistance...... to a susceptible E. faecium strain. The resulting transconjugants all tested positive for the presence of emtA, a gene encoding a methyltransferase previously linked with high-level evernimicin resistance. The four transconjugants derived from animal isolates all carried the same plasmid, while a differently sized...... plasmid was found in the isolate from humans. This study demonstrated a low incidence of high-level evernimicin resistance mediated by the emtA gene in different E. faecium isolates of animal and human origin....

Isolation and characterization of large spectrum and multiple bacteriocin-producing Enterococcus faecium strain from raw bovine milk.

Science.gov (United States)

Gaaloul, N; ben Braiek, O; Hani, K; Volski, A; Chikindas, M L; Ghrairi, T

2015-02-01

To assess the antimicrobial properties of lactic acid bacteria from Tunisian raw bovine milk. A bacteriocin-producing Enterococcus faecium strain was isolated from raw cow milk with activity against Gram-positive and Gram-negative bacteria. Antimicrobial substances produced by this strain were sensitive to proteolytic enzymes and were thermostable and resistant to a broad range of pH (2-10). Mode of action of antimicrobial substances was determined as bactericidal. Maximum activity was reached at the end of the exponential growth phase when checked against Listeria ivanovii BUG 496 (2366.62 AU ml(-1)). However, maximum antimicrobial activity against Pseudomonas aeruginosa 28753 was recorded at the beginning of the exponential growth phase. Enterococcus faecium GGN7 was characterized as free from virulence factors and was susceptible to tested antibiotics. PCR analysis of the micro-organism's genome revealed the presence of genes coding for enterocins A and B. Mass spectrometry analysis of RP-HPLC active fractions showed molecular masses corresponding to enterocins A (4835.77 Da) and B (5471.56 Da), and a peptide with a molecular mass of 3215.5 Da active only against Gram-negative indicator strains. The latter was unique in the databases. Enterococcus faecium GGN7 produces three bacteriocins with different inhibitory spectra. Based on its antimicrobial properties and safety, Ent. faecium GGN7 is potentially useful for food biopreservation. The results suggest the bacteriocins from GGN7 strain could be useful for food biopreservation. © 2014 The Society for Applied Microbiology.

High-density fecal Enterococcus faecium colonization in hospitalized patients is associated with the presence of the polyclonal subcluster CC17

NARCIS (Netherlands)

Ruiz-Garbajosa, P.; de Regt, M.; Bonten, M.; Baquero, F.; Coque, T. M.; Canton, R.; Harmsen, H. J. M.; Willems, Rob J. L.

Enterococcus faecium belonging to the polyclonal subcluster CC17, with a typical ampicillin-resistant E. faecium (AREfm) phenotype, have become prevalent among nosocomial infections around the world. High-density intestinal AREfm colonization could be one of the factors contributing to the

Caracterización bioquímica y genética de enterocinas producidas por cepas de "Enterococcus faecium" de origen cárnico : optimización de la producción molecular de acción de la enterocina P de "Enterococcus faecium" P13

OpenAIRE

Herranz Sorribes, Carmen

2001-01-01

En primer lugar, se identificaron las bacteriocinas producidas por Enterococcus faecium AA13, E. faecium G16 y E. faecium P21, tres cepas aisladas de chorizos españoles artesanos. Tras purificar a homogeneidad las bacteriocinas, se determinó su secuencia aminoacídica mediante degradación de Edman y, seguidamente, la secuencia nucleotídica de sus determinantes genéticos mediante clonación, PCR y secuenciación nucleotídica. Los resultados obtenidos indicaron que E. faecium AA13 y E. faecium G16...

Frecuencia de aislamiento de Staphylococcus spp meticilina resistentes y Enterococcus spp vancomicina resistentes en hospitales de Cuba Frequency of methicilline-resistant Staphylococcus spp and vancomycin-resistant Enterococcus spp isolates in Cuban hospitals

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Leonora González Mesa

2005-12-01

Full Text Available La resistencia a meticilina en el género Staphylococcus spp es un problema creciente en el ámbito mundial. La producción de una PBP alterada (PBP2a con baja afinidad a betalactámicos, mediada por el gen mec A, es la responsable de esta resistencia. Mientras que los Staphylococcus spp todavía permanecen sensibles a vancomicina, algunos Enterococcus spp han adquirido la capacidad de neutralizar esta droga. En nuestro país no se conocen datos actualizados sobre la tasa de infección por S. aureus meticilina resistente (SAMR, ni sobre la circulación de este germen en la comunidad, tampoco existen reportes de Enterococcus spp vancomicina resistente (EVR. En este estudio fueron analizadas 774 cepas, colectadas en hospitales del país. Se determinó el mecanismo de resistencia utilizando métodos sugeridos por las guías NCCLS. El 9.3 % (23 de los S. aureus aislados en los hospitales y 4.0% (7 S. aureus aislados en la comunidad, fueron SAMR, portadores del gen mec A, el 69.9 % (72 de Staphylococcus coagulasa negativo, fueron resistentes a oxacilina. En la detección del Enterococcus spp vancomicina resistente (EVR, se encontró una cepa portadora de este fenotipo. Nuestros resultados revelan que en nuestro país los SAMR no son un problema en los hospitales, ni en el ambiente comunitario, a pesar de que se reporta por primera vez la circulación de estos en la comunidad y la circulación de EVR en el ambiente hospitalario, su frecuencia es muy baja lo que refleja los avances obtenidos en la aplicación de políticas encaminadas a racionalizar el uso y consumo de antibióticos.Resistance to methicilline in Staphylococcus spp genus is a growing problem worldwide. The production of an altered penicillin-fixing protein with low mecA gen-mediated affinity to beta-lactams is responsible for this resistance. Although Staphylococcus spp still remain susceptible to vancomycin, some Enterococcus spp have acquired the capacity of neutralizing this drug. In

Effect of Enterococcus faecium SF68 on growth performance and in vivo digestibility in buffalo calves

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V. Proto

2010-04-01

Full Text Available The effect of dietary supplementation with Enterococcus faecium strain SF68 on growth performance, faecal consistency and in vivo digestibility in buffalo (Bubalus bubalis calves was evaluated. Forty calves were randomly assigned at 10 d of age to one of four treatments: (A milk replacer with no additive, (B milk replacer supplemented with 0.17 g/l of viable (2 x l09 cfu/g E. faecium bacteria daily for 3 days with an interval of 7 days throughout 11 weeks, (C milk replacer supplemented with E. faecium daily for 4 weeks, (D milk replacer supplemented with E. faecium daily for 11 weeks. A total mixed ration was offered ad libitum from 5th week of the experimental period. Faecal score was significantly better in E. faecium-treated calves than control ones. The use of E. faecium had no effect on average daily gain at any stage, total body weight (BW gain, dry matter intake or total tract digestibility. Therefore, E. faecium supplementation may be able to act favourably on the health of the gastrointestinal tract.

Sensibilidad antimicrobiana in vitro en aislamientos de Enterococcus faecalis y Enterococcus faecium obtenidos de pacientes hospitalizados

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Manuel Medell

2014-04-01

Full Text Available Introducción. Actualmente se considera a Enterococcus spp. como uno de los agentes de infección hospitalaria más importantes, siendo su resistencia a los antibióticos un problema importante en los centros de salud. Objetivos. Caracterizar la resistencia antimicrobiana en 50 cepas de Enterococcus spp. aisladas de muestras clínicas de pacientes hospitalizados. Materiales y métodos. Se llevó a cabo un estudio de tipo descriptivo observacional de corte transversal en 50 aislamientos clínicos de estas especies microbianas. Se trabajó un aislamiento por paciente. La identificación y la sensibilidad a los antibióticos se realizaron por métodos automatizados y convencionales. El análisis fenotípico de los mecanismos de resistencia a glucopéptidos se hizo según las recomendaciones de la Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. Resultados. De 50 aislamientos, 30 (60,0 % y 20 (40,0 % pertenecían a las especies de Enterococcus faecalis y Enterococcus faecium, respectivamente. La resistencia global expresada por este género fue de 38/50 (76,0 % para ampicilina; 33/50 (66,0 % para gentamicina de alto nivel; 34/50 (68,0 % para estreptomicina de alto nivel; 26/50 (52,0 % para ciprofloxacina; 4/50 (8,0 % para linezolid; 17/50 (34,0 % para teicoplanina; 25/50 (50,0 % para vancomicina; 31/50 (62,0 % para minociclina; 34/50 (68,0 % para tetraciclina y 9/50 (18,0 % para nitrofurantoina. Frente a los glucopéptidos, 25/50 (50,0 % y 10/50 (20,0 % de los aislamientos presentaron los mecanismos Van A y Van B, respectivamente. Conclusiones. Podemos concluir que la mayoría de las veces, las cepas aisladas en el Hospital Hermanos Ameijeiras mostraron porcentajes de resistencia por encima de lo reportado en la literatura científica consultada. El alto porcentaje de cepas con resistencia a la vancomicina podría influir en la aparición de otros gérmenes Gram positivos con resistencia a este fármaco. Se reporta por

Rapid Emergence of Resistance to Linezolid during Linezolid Therapy of an Enterococcus faecium Infection▿

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Seedat, Jamela; Zick, Günther; Klare, Ingo; Konstabel, Carola; Weiler, Norbert; Sahly, Hany

2006-01-01

We report the emergence of linezolid resistance (MICs of 16 to 32 mg/liter) in clonally related vancomycin-susceptible and -resistant Enterococcus faecium isolates from an intensive care unit patient after 12 days of linezolid therapy. Only linezolid-susceptible isolates of the same clone were detected at 28 days after termination of linezolid therapy.

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

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Guzman 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 degrees C and 45 degrees C. E. faecium has recently emerged as a multi-drug resistant nosocomial pathogen. We hypothesized that genes involved in

[BIOLOGICAL ACTIVITY OF ANTIMICROBIAL PEPTIDES OF ENTEROCOCCUS FAECIUM].

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Vasilchenko, A S; Rogozhin, E A; Valyshev, A V

2015-01-01

Isolate bacteriocins from Enterococcus faecium metabolites and characterize their effect on cells of Gram positive (Listeria monocytogenes) and Gram negative (Escherichia coli) bacteria. Methods of solid-phase extraction, ion-exchange and reversed phase chromatography were applied for isolation of bacteriocins from cultural medium of bacteria MALDI time-of-flight mass-spectrometry was used for characterization of the obtained preparations. The mechanism of biological effect of peptides was evaluated using DNA-tropic dyes (SYTO 9 and PI) with subsequent registration of fluorescence spectra: Atomic-force microscopy (AFM) was used for characterization of morpho-functional reaction of target cells. Peptide fractions with mass of 1.0 - 3.0 kDa were isolated from enterococci metabolites, that inhibit the growth of indicator microorganisms. E. faecium strain exoproducts were shown to increase membrane permeability during interaction with L. monocytogenes, that results in subsequent detectable disturbance of normal cell morphology of listeria. Alterations of E. coli surface during the effect of purified peptide fraction was detected using AFM. The studies carried out have revealed the effect of bacteriocins of enterococci on microorganisms with various types of cell wall composition and have confirmed the importance of bacterial barrier structure permeability disturbance in the mechanism of antimicrobial effect of enterocins.

Investigating the mobilome in clinically important lineages of Enterococcus faecium and Enterococcus faecalis.

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Mikalsen, Theresa; Pedersen, Torunn; Willems, Rob; Coque, Teresa M; Werner, Guido; Sadowy, Ewa; van Schaik, Willem; Jensen, Lars Bogø; Sundsfjord, Arnfinn; Hegstad, Kristin

2015-04-10

The success of Enterococcus faecium and E. faecalis evolving as multi-resistant nosocomial pathogens is associated with their ability to acquire and share adaptive traits, including antimicrobial resistance genes encoded by mobile genetic elements (MGEs). Here, we investigate this mobilome in successful hospital associated genetic lineages, E. faecium sequence type (ST)17 (n=10) and ST78 (n=10), E. faecalis ST6 (n=10) and ST40 (n=10) by DNA microarray analyses. The hybridization patterns of 272 representative targets including plasmid backbones (n=85), transposable elements (n=85), resistance determinants (n=67), prophages (n=29) and clustered regularly interspaced short palindromic repeats (CRISPR)-cas sequences (n=6) separated the strains according to species, and for E. faecalis also according to STs. RCR-, Rep_3-, RepA_N- and Inc18-family plasmids were highly prevalent and with the exception of Rep_3, evenly distributed between the species. There was a considerable difference in the replicon profile, with rep 17/pRUM , rep 2/pRE25 , rep 14/EFNP1 and rep 20/pLG1 dominating in E. faecium and rep 9/pCF10 , rep 2/pRE25 and rep 7 in E. faecalis strains. We observed an overall high correlation between the presence and absence of genes coding for resistance towards antibiotics, metals, biocides and their corresponding MGEs as well as their phenotypic antimicrobial susceptibility pattern. Although most IS families were represented in both E. faecalis and E. faecium, specific IS elements within these families were distributed in only one species. The prevalence of IS256-, IS3-, ISL3-, IS200/IS605-, IS110-, IS982- and IS4-transposases was significantly higher in E. faecium than E. faecalis, and that of IS110-, IS982- and IS1182-transposases in E. faecalis ST6 compared to ST40. Notably, the transposases of IS981, ISEfm1 and IS1678 that have only been reported in few enterococcal isolates were well represented in the E. faecium strains. E. faecalis ST40 strains harboured

Production of enterocin A by Enterococcus faecium MMRA isolated from 'Rayeb', a traditional Tunisian dairy beverage.

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Rehaiem, A; Martínez, B; Manai, M; Rodríguez, A

2010-05-01

Characterization and purification of a bacteriocin produced by a wild Enterococcus faecium strain, isolated from a Tunisian traditional fermented milk. Enterococcus faecium MMRA was selected on the basis of its strong anti-Listeria activity. The antibacterial activity was sensitive to proteases, confirming its proteinaceous nature. It was extremely heat stable (15 min at 121 degrees C), remained active over a wide pH range (2-12), and also after treatment with lipase, amylase, organic solvents, detergents, lyophilisation and long-term storage at -20 degrees C. Production of the bacteriocin occurred throughout the logarithmic growth phase, it did not adhere to the surface of the producer cells and the mode of action was bactericidal. After partial purification of the active supernatants, a 4-kDa band with antibacterial activity was revealed by SDS-PAGE electrophoresis and bioassay. Tryptic digestion followed by MALDI-TOF mass spectrometry identified the peptide as enterocin A. The inhibitory activity of Ent. faecium MMRA, a wild strain isolated from the artisan dairy beverage 'Rayeb', is due to the synthesis of an enterocin A. Traditional fresh Tunisian fermented dairy products are generally manufactured with raw milk that can be used as a source of uncharacterized wild lactic acid bacteria strains. To our knowledge, this is the first report on the isolation of an enterocin A producing Ent. faecium from 'Rayeb'. This bacteriocin or the producing strain might have a promising potential in biopreservation to enhance the hygienic quality of this dairy product.

Genome Sequence of Enterococcus faecium Strain ICIS 96 Demonstrating Intermicrobial Antagonism Associated with Bacteriocin Production.

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Pashkova, Tatiana M; Vasilchenko, Alexey S; Khlopko, Yuriy A; Kochkina, Elena E; Kartashova, Olga L; Sycheva, Maria V

2018-03-08

We report here the complete genome sequence of Enterococcus faecium strain ICIS 96, which was isolated from the feces of a horse. Bacteriological characterization of strain ICIS 96 revealed the absence of pathogenicity factors, while its spectrum of antagonistic activity was found to be broad, having activities associated with both Gram-positive and Gram-negative bacteria. Analysis of the E. faecium ICIS 96 genome revealed five genes associated with antimicrobial activity (enterocin [ent] A, ent B, lactobin A/cerein 7b, and ent L50 A/B). No genes that correlate with human pathogenicity were identified. Copyright © 2018 Pashkova et al.

[Emergence of glycopeptide resistant Enterococcus faecium in Algeria: a case report].

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Hamidi, Moufida; Ammari, Houria; Ghaffor, Mohamed; Benamrouche, Nabila; Tali-Maamar, Hassiba; Tala-Khir, Farida; Younsi, Mokhtar; Rahal, Kheira

2013-01-01

A glycopeptide-resistant Enterococcus faecium (EFRG) was isolated from a wound in a patient hospitalized in a university hospital in Algiers. This strain was resistant to several antibiotics. This patient was carrying this strain in the digestive tract which may partly explain its origin. Genotypic comparison of the two strains by pulsed field gel electrophoresis showed that it was the same strain. Glycopeptide resistance was due to the presence of the vanA gene. Vigilance is required facing the emergence of strains of EFRG in our hospitals.

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

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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 Acm adherence with functional subsegment-specific antibodies raises the possibility of their use as therapeutic or prophylactic agents.

High Rate of Resistance to Quinupristin-Dalfopristin in Enterococcus faecium Clinical Isolates from Korea

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Oh, Won Sup; Ko, Kwan Soo; Song, Jae-Hoon; Lee, Mi Young; Park, Sulhee; Peck, Kyong Ran; Lee, Nam Yong; Kim, Choon-Kwan; Lee, Hyuck; Kim, Shin-Woo; Chang, Hyun-Ha; Kim, Yeon-Sook; Jung, Sook-In; Son, Jun Seong; Yeom, Joon-Sup; Ki, Hyun Kyun; Woo, Gun-Jo

2005-01-01

We tested the in vitro susceptibilities of 603 enterococcal isolates from eight tertiary-care hospitals in Korea. The quinupristin-dalfopristin resistance rate in Enterococcus faecium was very high (25 isolates, 10.0%). It was suggested that both clonal spread and the sporadic emergence of quinupristin-dalfopristin-resistant isolates may explain the high prevalence of quinupristin-dalfopristin resistance in Korea. PMID:16304198

Failure of daptomycin β-Lactam combination therapy to prevent resistance emergence in Enterococcus faecium.

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Menon, Vidthiya; Davis, Rebecca; Shackel, Nick; Espedido, Bjorn A; Beukers, Alicia G; Jensen, Slade O; van Hal, Sebastiaan J

2018-02-01

Daptomycin β-Lactam combination therapy offers "protection" against daptomycin non-susceptibility (DNS) development in Enterococcus faecium. We report failure of this strategy and the importance of source control. Mutations were detected in the LiaF and cls genes in DNS isolates. A single DNS isolate contained an unrecognized mutation, which requires confirmation. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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Mingyue Sun

2014-09-01

Full Text Available 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 vanC1and 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.

Antibiotics and heavy metals resistance patterns of Enterococcus faecalis and faecium bacteria isolated from the human and the livestock sources

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Yaser Sharifi

2015-12-01

Full Text Available Background: Enterococci have emerged as a major cause of nosocomial infections and within this group, Enterococcus faecalis and Enterococcus faecium cause the majority of human and livestock enterococcal infections. In this article, we tried to determine antibiotics and metals resistance patterns of E. faecalis and E. faecium strains. Methods: One hundred sixty different strains of E. faecalis and E. faecium were collected from livestock sewage and the human fecal waste during 15 months. Then bacterial antibiotics sensitivity tests were carried out using the Agar disc diffusion method. Results: Generally, 100% of E. faecalis strains separated from human and livestock sources (i.e. sheep showed penicillin (P/ kanamycin (K/ nitrofurantoin (N/ loracarbef (L/ Ciprofloxacin (Cc/ ampicillin (AN/ nalidixic acid (NA/ sulfamethoxazole (S antibiotics resistance patterns. In addition, 55% of isolated E. faecium showed P/S/AN/NA antibiotics resistance patterns. Each strain showed a resistance to at least two aminoglycoside antibiotics. However, E. faecalis strains from human and the livestock sources showed 94% and 100% of resistance to nitrofurantoin, respectively. The effects of different metal concentrations was evaluated in both strains. The agar dilution method was applied in this stage. Hg at 0.05 mmol/L of minimum inhibitory concentration (MIC showed toxicity to both the human and livestock Enterococcus strains. Cadmium at 1 mmol/L and 0.5 mmol/L concentrations had the most toxicity to E. faecalis and E. faecium strains, respectively. Obviously, toxicity to bacteria is less than other metals. As a result, Zn/Ni/Cu/Co resistance pattern is suggested for both strains. Finally, antibiotics and heavy metals resistance patterns were monitored simultaneously. Conclusion: Almost all E. faecalis strains isolated from humans and livestock showed antibiotics and heavy metals resistance patterns of P/K/L/Cc/S/AN/NA/Zn/Cu/Co simultaneously. Moreover, 55% of E

Resistance mechanisms of linezolid-nonsusceptible enterococci in Korea: low rate of 23S rRNA mutations in Enterococcus faecium.

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Lee, Sae-Mi; Huh, Hee Jae; Song, Dong Joon; Shim, Hyang Jin; Park, Kyung Sun; Kang, Cheol-In; Ki, Chang-Seok; Lee, Nam Yong

2017-12-01

To investigate linezolid-resistance mechanisms in linezolid-nonsusceptible enterococci (LNSE) isolated from a tertiary hospital in Korea. Enterococcal isolates exhibiting linezolid MICs ≥4 mg l -1 that were isolated between December 2011 and May 2016 were investigated by PCR and sequencing for mutations in 23S rRNA or ribosomal proteins (L3, L4 and L22) and for the presence of cfr, cfr(B) and optrA genes.Results/Key findings. Among 135 LNSE (87 Enterococcus faecium and 48 Enterococcus faecalis isolates), 39.1 % (34/87) of E. faecium and 18.8 % (9/48) of E. faecalis isolates were linezolid-resistant. The optrA carriage was the dominant mechanism in E. faecalis: 13 isolates, including 10 E. faecalis [70 % (7/10) linezolid-resistant and 30 % (3/10) linezolid-intermediate] and three E. faecium [33.3 % (1/3) linezolid-resistant and 66.7 % (2/3) linezolid-intermediate], contained the optrA gene. G2576T mutations in the 23S rRNA gene were detected only in E. faecium [14 isolates; 71.4 % (10/14) linezolid-resistant and 28.6 % (4/14) linezolid-intermediate]. One linezolid-intermediate E. faecium harboured a L22 protein alteration (Ser77Thr). No isolates contained cfr or cfr(B) genes and any L3 or L4 protein alterations. No genetic mechanism of resistance was identified for 67.6 % (23/34) of linezolid-resistant E. faecium. A low rate of 23S rRNA mutations and the absence of known linezolid-resistance mechanisms in the majority of E. faecium isolates suggest regional differences in the mechanisms of linezolid resistance and the possibility of additional mechanisms.

Atypical Genetic Locus Associated with Constitutive Production of Enterocin B by Enterococcus faecium BFE 900

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Franz, Charles M. A. P.; Worobo, Randy W.; Quadri, Luis E. N.; Schillinger, Ulrich; Holzapfel, Wilhelm H.; Vederas, John C.; Stiles, Michael E.

1999-01-01

A purified bacteriocin produced by Enterococcus faecium BFE 900 isolated from black olives was shown by Edman degradation and mass spectrometric analyses to be identical to enterocin B produced by E. faecium T136 from meat (P. Casaus, T. Nilsen, L. M. Cintas, I. F. Nes, P. E. Hernández, and H. Holo, Microbiology 143:2287–2294, 1997). The structural gene was located on a 2.2-kb HindIII fragment and a 12.0-kb EcoRI chromosomal fragment. The genetic characteristics and production of EntB by E. faecium BFE 900 differed from that described so far by the presence of a conserved sequence like a regulatory box upstream of the EntB gene, and its production was constitutive and not regulated. The 2.2-kb chromosomal fragment contained the hitherto undetected immunity gene for EntB in an atypical orientation that is the reverse of that of the structural gene. Typical transport and other genes associated with bacteriocin production were not detected on the 12.0-kb chromosomal fragment containing the EntB structural gene. This makes the EntB genetic system different from most other bacteriocin systems, where transport and possible regulatory genes are clustered. EntB was subcloned and expressed by the dedicated secretion machinery of Carnobacterium piscicola LV17A. The structural gene was amplified by PCR, fused to the divergicin A signal peptide, and expressed by the general secretory pathway in Enterococcus faecalis ATCC 19433. PMID:10224016

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

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Donna M. Ferguson

2016-01-01

Full Text Available 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.

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

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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 Acm the first factor shown to be important for E. 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.

Evaluation of Enterococcus faecium NRRL B-2354 as a Surrogate for Salmonella During Extrusion of Low-Moisture Food.

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Verma, Tushar; Wei, Xinyao; Lau, Soon Kiat; Bianchini, Andreia; Eskridge, Kent M; Subbiah, Jeyamkondan

2018-04-01

Salmonella in low-moisture foods is an emerging challenge due to numerous food product recalls and foodborne illness outbreaks. Identification of suitable surrogate is critical for process validation at industry level due to implementation of new Food Safety Modernization Act of 2011. The objective of this study was to evaluate Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella during the extrusion of low-moisture food. Oat flour, a low-moisture food, was adjusted to different moisture (14% to 26% wet basis) and fat (5% to 15% w/w) contents and was inoculated with E. faecium NRRL B-2354. Inoculated material was then extruded in a lab-scale single-screw extruder running at different screw speeds (75 to 225 rpm) and different temperatures (75, 85, and 95 °C). A split-plot central composite 2nd order response surface design was used, with the central point replicated six times. The data from the selective media (m-Enterococcus agar) was used to build the response surface model for inactivation of E. faecium NRRL B-2354. Results indicated that E. faecium NRRL B-2354 always had higher heat resistance compared to Salmonella at all conditions evaluated in this study. However, the patterns of contour plots showing the effect of various product and process parameters on inactivation of E. faecium NRRL B-2354 was different from that of Salmonella. Although E. faecium NRRL B-2354 may be an acceptable surrogate for extrusion of low-moisture products due to higher resistance than Salmonella, another surrogate with similar inactivation behavior may be preferred and needs to be identified. Food Safety Modernization Act requires the food industry to validate processing interventions. This study validated extrusion processing and demonstrated that E. faecium NRRL B-2354 is an acceptable surrogate for extrusion of low-moisture products. The developed response surface model allows the industry to identify process conditions to achieve a desired lethality for their

Análisis clínico-epidemiológico de la portación intestinal de enterococos resistentes a vancomicina en una unidad de terapia intensiva Clinical and epidemiologic analysis of intestinal tract colonization with vancomycin-resistant enterococci in an intensive care unit

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A.M. Togneri

2005-03-01

Full Text Available En un período de cinco meses y 25 días se investigó la portación intestinal de enterococos resistentes a vancomicina (EVR. Se estudiaron 124 pacientes (73% de 171 admitidos en la unidad de terapia intensiva (UTI, 35 de los cuales (28% resultaron ser portadores. Los aislamientos de EVR (n=35 fueron identificados como Enterococcus faecium (n=18, Enterococcus gallinarum (n=16 y Enterococcus raffinosus (n=1. Todos los aislamientos estudiados fueron resistentes a vancomicina (VAN (CIM90= 512 µg/ml y teicoplanina (CIM90= 32 µg/ml y portaban el gen vanA. Los estudios de tipificación molecular mostraron un alto grado de homología entre los aislamientos de E. faecium (un clon dominante y E. gallinarum (dos tipos clonales, sugiriendo su diseminación a modo de brote. No se encontraron diferencias significativas con la edad y el sexo de los pacientes no portadores (p>0,05, pero si con el tiempo de hospitalización y el uso de esquemas antibióticos de amplio espectro (pIntestinal tract colonization with vancomycin resistant enterococci (VRE was studied during five months and 25 days. Out of 171 patients hospitalized in the intensive care unit, 124 (73% were included in this study. Thirty five of them (28% were recognized as colonized with VRE. VRE isolates (n = 35 were identified as Enterococcus faecium (n=18, Enterococcus gallinarum (n=16, and Enterococcus raffinosus (n=1. All of them were resistant to vancomycin (MIC90= 512 µg/ml and to teicoplanin (MIC90= 32 µg/ml, having the vanA gene. By means of molecular methods a high homology was found among E. faecium and E. gallinarum isolates, respectively, suggesting their spread as a kind of outbreak. No significant differences in age or sex were found among colonized and non-colonized patients (p>0.05. On the other hand, the hospitalization time and the use of broad-spectrum antibiotics were associated with colonization. From this study we highlight the importance of enhancing all measures of

Co-diversification of Enterococcus faecium core genomes and PBP5: evidences of pbp5 horizontal transfer

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Carla Novais

2016-10-01

Full Text Available 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.

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

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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

Increasing Incidence of Linezolid-Intermediate or -Resistant, Vancomycin-Resistant Enterococcus faecium Strains Parallels Increasing Linezolid Consumption▿

OpenAIRE

Scheetz, Marc H.; Knechtel, Stephanie A.; Malczynski, Michael; Postelnick, Michael J.; Qi, Chao

2008-01-01

Clinical enterococcal resistance to linezolid is defined by the presence of the G2576T mutation. We evaluated the incidence of genetically proven linezolid resistance among vancomycin-resistant Enterococcus faecium strains and linezolid consumption for a possible association. A relationship was found (r2 = 0.73, P = 0.03) and predicts increasing resistance with current trends of linezolid use.

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

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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

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

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Ana María Sánchez-Díaz

Full Text Available 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.

Streptogramin resistance among Enterococcus faecium isolated from production animals in Denmark in 1997

DEFF Research Database (Denmark)

Jensen, Lars Bogø; Hammerum, Anette Marie; Bager, Flemming

2002-01-01

The genetic background for streptogramin resistance was examined in Enterococcus faecium isolated from pigs (n = 55) and broilers (n = 207) in 1997 in Denmark. Fifty-one percent and 67%, respectively, of the isolates were resistant to streptogramins. Among streptogramin-resistant E. faecium (SREF......), the genetic background for streptogramin A resistance could be determined in 96% of the isolates from broilers, compared with 14% among SREF from pigs. For broiler isolates 89% of SREF contained the vat(E) gene and 10% the vat(D) gene. Three of these isolates contained both resistance genes. Among SREF from...... pigs two isolates contained the vat(E) gene and two others the vat(D) gene. The genetic background for streptogramin B was most often identified as the erm(B) gene encoding macrolide, lincosamide, and streptogramin B (MLSB) resistance. Among SREF, 84% and 86% of isolates from broilers and pigs...

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

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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.

Bacteriocin-Producing Enterococcus faecium LCW 44: A High Potential Probiotic Candidate from Raw Camel Milk.

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Vimont, Allison; Fernandez, Benoît; Hammami, Riadh; Ababsa, Ahlem; Daba, Hocine; Fliss, Ismaïl

2017-01-01

Bacterial isolates from raw camel milk were screened for antibacterial activity using the agar diffusion assay. Ten isolates selected for their inhibition of Gram-positive bacteria were identified by 16S sequencing as Enterococcus faecium or durans . An isolate named E. faecium LCW 44 exhibited the broadest antibacterial spectrum with an inhibitory activity against several Gram-positive strains belonging to the genera Clostridium , Listeria , Staphylococcus , and Lactobacillus. E. faecium LCW 44 was shown to produce N-formylated enterocins L50A and L50B, as revealed by mass spectrometry and PCR analyses. This isolate did not harbor any of the virulence factors tested and was shown to be sensitive to all tested antibiotics. It showed high resistance to gastric and intestinal conditions (78 ± 4% survival). Its adhesion index was evaluated at 176 ± 86 and 24 ± 86 on Caco-2 cells and HT-29 cells, respectively, and it significantly reduced adhesion of Listeria monocytogenes by 65 and 49%, respectively. In Macfarlane broth (simulating the nutrient content of the colon), counts of L. monocytogenes were reduced by 2 log 10 cycles after 24 h in co-culture with E. faecium LCW 44, compared to the increase of 4 log 10 cycles when cultured alone. Comparison with a bacteriocin-non-producing mutant of E. faecium LCW 44 strongly suggests that inhibition of L. monocytogenes was due to bacteriocin production. Altogether, E. faecium LCW 44 thus has potential for use as a probiotic for humans and veterinary medicine.

Bacteriocin-Producing Enterococcus faecium LCW 44: A High Potential Probiotic Candidate from Raw Camel Milk

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Allison Vimont

2017-05-01

Full Text Available Bacterial isolates from raw camel milk were screened for antibacterial activity using the agar diffusion assay. Ten isolates selected for their inhibition of Gram-positive bacteria were identified by 16S sequencing as Enterococcus faecium or durans. An isolate named E. faecium LCW 44 exhibited the broadest antibacterial spectrum with an inhibitory activity against several Gram-positive strains belonging to the genera Clostridium, Listeria, Staphylococcus, and Lactobacillus. E. faecium LCW 44 was shown to produce N-formylated enterocins L50A and L50B, as revealed by mass spectrometry and PCR analyses. This isolate did not harbor any of the virulence factors tested and was shown to be sensitive to all tested antibiotics. It showed high resistance to gastric and intestinal conditions (78 ± 4% survival. Its adhesion index was evaluated at 176 ± 86 and 24 ± 86 on Caco-2 cells and HT-29 cells, respectively, and it significantly reduced adhesion of Listeria monocytogenes by 65 and 49%, respectively. In Macfarlane broth (simulating the nutrient content of the colon, counts of L. monocytogenes were reduced by 2 log10 cycles after 24 h in co-culture with E. faecium LCW 44, compared to the increase of 4 log10 cycles when cultured alone. Comparison with a bacteriocin-non-producing mutant of E. faecium LCW 44 strongly suggests that inhibition of L. monocytogenes was due to bacteriocin production. Altogether, E. faecium LCW 44 thus has potential for use as a probiotic for humans and veterinary medicine.

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

NARCIS (Netherlands)

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.

2016-01-01

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

Outbreak of vancomycin-resistant Enterococcus faecium in a haematology unit: risk factor assessment and successful control of the epidemic

NARCIS (Netherlands)

Timmers, Gert Jan; van der Zwet, Wil C.; Simoons-Smit, Ina M.; Savelkoul, Paul H. M.; Meester, Helena H. M.; Vandenbroucke-Grauls, Christina M. J. E.; Huijgens, Peter C.

2002-01-01

We describe an outbreak of vancomycin-resistant Enterococcus faecium (VRE) on the haematology ward of a Dutch university hospital. After the occurrence of three consecutive cases of bacteraemia with VRE, strains were genotyped and found to be identical. During the next 4 months an intensive

Enterococcus faecium NCIMB 10415 Modulates Epithelial Integrity, Heat Shock Protein, and Proinflammatory Cytokine Response in Intestinal Cells

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Shanti Klingspor

2015-01-01

Full Text Available Probiotics have shown positive effects on gastrointestinal diseases; they have barrier-modulating effects and change the inflammatory response towards pathogens in studies in vitro. The aim of this investigation has been to examine the response of intestinal epithelial cells to Enterococcus faecium NCIMB 10415 (E. faecium, a probiotic positively affecting diarrhea incidence in piglets, and two pathogenic Escherichia coli (E. coli strains, with specific focus on the probiotic modulation of the response to the pathogenic challenge. Porcine (IPEC-J2 and human (Caco-2 intestinal cells were incubated without bacteria (control, with E. faecium, with enteropathogenic (EPEC or enterotoxigenic E. coli (ETEC each alone or in combination with E. faecium. The ETEC strain decreased transepithelial resistance (TER and increased IL-8 mRNA and protein expression in both cell lines compared with control cells, an effect that could be prevented by pre- and coincubation with E. faecium. Similar effects were observed for the increased expression of heat shock protein 70 in Caco-2 cells. When the cells were challenged by the EPEC strain, no such pattern of changes could be observed. The reduced decrease in TER and the reduction of the proinflammatory and stress response of enterocytes following pathogenic challenge indicate the protective effect of the probiotic.

Simple test of synergy between ampicillin and vancomycin for resistant strains of Enterococcus faecium.

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Green, M; Barbadora, K; Wadowsky, R M

1994-11-01

The combination of ampicillin and vancomycin kills some but not all strains of ampicillin- and vancomycin-resistant Enterococcus faecium. We compared a simple test for synergy utilizing a commercially available microdilution susceptibility system with time-kill studies and determined acceptable breakpoints for this test for 20 strains of ampicillin- and vancomycin-resistant E. faecium. The combination of ampicillin and vancomycin was tested for synergy by time-kill, broth macrodilution, and broth microdilution procedures. Repeat testing of isolates by macro- and microdilution synergy methods yielded MICs that were within one twofold dilution of each other for both intra- and intertest comparisons. Synergy was always detected by time-kill studies when the MIC of ampicillin in the combination synergy screen was 16 micrograms/ml in the combination microdilution synergy screen. The determination of the synergy by the broth microdilution procedure appears to be simple, convenient, and accurate.

In vivo model experiment using laying hens treated with Enterococcus faecium EM41 from ostrich faeces and its enterocin EM41

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Andrea Lauková1,

2017-10-01

Full Text Available Enterococcus faecium EM41 is an isolate from ostrich faeces. It produces a thermo-stable proteinaceous substance, bacteriocin (enterocin EM41 with the highest inhibition activity in late logarithmic phase of growth (25 600 AU/ml. This strain and its enterocin have not been previously tested in animals. Lohmann Brown laying hens (aged 45 weeks were involved in this model/pilot experiment, divided into 3 groups 6 birds in each. E. faecium EM41 applied was a variant treated with rifampicin (109 cfu/ml, dose 400 μl/animal/day to differentiate it from the other enterococci. Partially-purified enterocin EM41 (Ent EM41, dose 40 μl/animal/day and its producer were applied to water for 21 days. The experiment lasted 35 days. Sampling was performed at days 0 - 1, 21 (3 weeks of additive application, 35 (2 weeks after cessation of additive application from every bird. E. faecium EM41 sufficiently colonized the intestinal tract of laying hens from the initial concentration 109 cfu/g, its count reached 4.30 log cfu/g at day 21. PCR genotypization confirmed the identity of the EM41 strain with the species Enterococcus faecium. E. faecium EM41 and its enterocin EM41 showed antimicrobial effects demonstrated by reduction of coagulase-positive and coagulase-negative staphylococci, coliforms, Pseudomonas spp., Aeromonas spp. and Campylobacter spp. The hens were Salmonella spp. free. After administration of both additives, phagocytic activity was stimulated with a significant increase. The additives did not negatively influence biochemical and haematological parameters or weight gains.

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

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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

Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

Science.gov (United States)

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.

Comparison of Enterococcus faecium and Enterococcus faecalis Strains isolated from water and clinical samples: antimicrobial susceptibility and genetic relationships.

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Gonzalo Castillo-Rojas

Full Text Available 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.

Purification and characterization of enterocin FH 99 produced by a faecal isolate Enterococcus faecium FH 99.

Science.gov (United States)

Gupta, H; Malik, R K; Bhardwaj, A; Kaur, G; De, S; Kaushik, J K

2010-06-01

Enterococcus faecium FH 99 was isolated from human faeces and selected because of its broad spectrum of inhibitory activity against several Gram-positive foodborne spoilage and pathogenic bacteria. Ent. faecium FH 99 accumulates enterocin in large number in early stationary phase of the growth. The enterocin FH 99 was stable over a wide pH range (2-10) and recovered activity even after treatment at high temperatures (10 min at 100°C). The enterocin was subjected to different purification techniques viz., gel filteration, cation exchange chromatography and reverse-phase high-performance liquid chromatography. The activity was eluted as one individual active fraction. SDSPAGE revealed a molecular weight of less than 6.5 kDa. Studies carried out to identify the genetic determinants for bacteriocin production showed that this trait may be plasmid encoded as loss in both of the plasmids (size>chromosomal DNA) led to loss in bacteriocin production by Ent. faecium FH 99. Ent. faecium strain FH 99 is a newly discovered high bacteriocin producer with Activity Units 1.8 × 10(5) AU ml(-1) and its characteristics indicate that it may have strong potential for application as a protective agent against pathogens and spoilage bacteria in foods.

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

Science.gov (United States)

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 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. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Single nucleotide polymorphism analysis of the enterocin P structural gene of Enterococcus faecium strains isolated from nonfermented animal foods.

Science.gov (United States)

Arlindo, Samuel; Calo, Pilar; Franco, Carlos; Prado, Marta; Cepeda, Alberto; Barros-Velázquez, Jorge

2006-12-01

The bacteriocins produced by two lactic acid bacteria isolated from nonfermented fresh meat and fish, respectively, and exhibiting a remarkable antilisterial activity, were characterized. Bacteriocinogenic strains were identified as Enterococcus faecium and the maximum bacteriocin production by both strains was detected in the stationary phase of growth. The activity against Listeria monocytogenes was maintained in pH range of 3-7 and was stable in both strains after heating at 100 or 121 degrees C. The genes coding for enterocin P were detected, isolated, and sequenced in both E. faecium strains. They exhibited DNA/DNA homology in the 87.1-97.2% range with respect to the other four enterocin P genes reported so far. Three single nucleotide polymorphism events, silent at the amino acid level, were detected at nucleotide positions 45 (G/A), 75 (A/G), and 90 (T/C) in E. faecium LHICA 28-4 and may explain the differences reported for those loci in other enterocin P-producing E. faecium strains. This work provides the first description of enterocin P-producing E. faecium strains in nonfermented foodstuffs and, in the case of E. faecium LHICA 51, the first report of an enterocin P-producing strain isolated from fish so far.

Aging Eye Microbiota in Dry Eye Syndrome in Patients Treated with Enterococcus faecium and Saccharomyces boulardii.

Science.gov (United States)

Chisari, Giuseppe; Chisari, Eleonora M; Borzi, Antonio M; Chisari, Clara G

2017-01-01

Aging and oxidative stress seem to play a key role in the onset and progression of ocular surface diseases. Dry Eye Syndrome (DES) is a multifactorial disease of the tears and ocular surface in which symptoms may interfere with the ability to work and carry out daily functions. This clinical trial was a pilot study to evaluate the effects of supplementation with mixture (Saccharomyces boulardii MUCL 53837 and Enterococcus faecium LMG S-28935) on the tear film. Following the run-in period subjects were randomized in two groups: group A (n.30 subjects) and group B (n.30 subjects). Group A (control) treated only with substitute tear and group B treated with substitute tear + mixture (probiotic). The data obtained in the two study groups A and B were, respectively the following: Schirmer I: 9.2±0.2 vs. 12.8±0.4 (pSaccharomyces boulardii MUCL 53837 and Enterococcus faecium LMG S-28935) activity integration with the action of tear substitutes, along with standardization of clinical parameters of the tear film and microbiological activity in restoring of the microbiota ocular surface subject with DES. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Photodynamic and antibiotic therapy impair the pathogenesis of Enterococcus faecium in a whole animal insect model.

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José Chibebe Junior

Full Text Available Enterococcus faecium has emerged as one of the most important pathogens in healthcare-associated infections worldwide due to its intrinsic and acquired resistance to many antibiotics, including vancomycin. Antimicrobial photodynamic therapy (aPDT is an alternative therapeutic platform that is currently under investigation for the control and treatment of infections. PDT is based on the use of photoactive dye molecules, widely known as photosensitizer (PS. PS, upon irradiation with visible light, produces reactive oxygen species that can destroy lipids and proteins causing cell death. We employed Galleria mellonella (the greater wax moth caterpillar fatally infected with E. faecium to develop an invertebrate host model system that can be used to study the antimicrobial PDT (alone or combined with antibiotics. In the establishment of infection by E. faecium in G. mellonella, we found that the G. mellonella death rate was dependent on the number of bacterial cells injected into the insect hemocoel and all E. faecium strains tested were capable of infecting and killing G. mellonella. Antibiotic treatment with ampicillin, gentamicin or the combination of ampicillin and gentamicin prolonged caterpillar survival infected by E. faecium (P = 0.0003, P = 0.0001 and P = 0.0001, respectively. In the study of antimicrobial PDT, we verified that methylene blue (MB injected into the insect followed by whole body illumination prolonged the caterpillar survival (P = 0.0192. Interestingly, combination therapy of larvae infected with vancomycin-resistant E. faecium, with antimicrobial PDT followed by vancomycin, significantly prolonged the survival of the caterpillars when compared to either antimicrobial PDT (P = 0.0095 or vancomycin treatment alone (P = 0.0025, suggesting that the aPDT made the vancomycin resistant E. faecium strain more susceptible to vancomycin action. In summary, G. mellonella provides an invertebrate model host to

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

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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

Enterocin HZ produced by a wild Enterococcus faecium strain isolated from a traditional, starter-free pickled cheese.

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Yildirim, Zeliha; Bilgin, Harun; Isleroglu, Hilal; Tokatli, Kader; Sahingil, Didem; Yildirim, Metin

2014-05-01

Bacteriogenic Enterococcus faecium HZ was identified by using biochemical (Strep-API 20, API-50 CHL, fatty acid profile) and 16S rRNA analysis (99·99 %). Ent. faecium HZ was sensitive to clinically important antibiotics such as vancomycin, and did not have gelatinase and haemolysis activities. Enterocin HZ, a bacteriocin from Ent. faecium HZ, was sensitive to papain and tyripsin, but resistant to pepsin, lipase, catalase, α-amylase, organic solvents, detergents, ß-mercaptoethanol, and heat treatment (90 °C/30 min). It was biologically active at pH 2·0-9·0 and synthesised at the highest level in MRS or M17 broth at 32 or 37 °C with an inoculum amount of 0·1-0·5 % and an initial pH of 6·0-7·0. Enterocin HZ production reached maximum level at middle and late logarithmic phase and its molecular weight was ∼4·5 kDa. It was active against some Gram-positive foodborne bacteria. Ent. faecium HZ or its bacteriocin enterocin HZ is a good candidate to be studied as a food biopreservative since enterocin HZ showed strong bactericidal activity against Listeria monocytogenes in UHT milk and also Ent. faecium HZ grew very well in milk and produced enterocin HZ at maximum level.

Enterocin X, a novel two-peptide bacteriocin from Enterococcus faecium KU-B5, has an antibacterial spectrum entirely different from those of its component peptides.

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Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji

2010-07-01

Enterocin X, composed of two antibacterial peptides (Xalpha and Xbeta), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xalpha and Xbeta display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known.

Enterocin X, a Novel Two-Peptide Bacteriocin from Enterococcus faecium KU-B5, Has an Antibacterial Spectrum Entirely Different from Those of Its Component Peptides▿

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Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji

2010-01-01

Enterocin X, composed of two antibacterial peptides (Xα and Xβ), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xα and Xβ display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known. PMID:20418437

Delayed-Onset Post-Keratoplasty Endophthalmitis Caused by Vancomycin-Resistant Enterococcus faecium

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Julio C. Hernandez-Camarena

2012-10-01

Full Text Available Background: Vancomycin-resistant Enterococcus (VRE endophthalmitis after penetrating keratoplasty (PKP is very rare, the management is a challenge due to both the pattern of antibiotic resistance and the aggressive nature of the infectious process. We report the first delayed-onset case of VRE endophthalmitis after PKP. Materials and Methods: Case report of a 51-year-old female with a 7-week history of PKP who arrived at the emergency room with signs and symptoms of endophthalmitis. Initial visual acuity was light perception, and a posterior pole exam was not possible due to the intense vitreous reaction. Mode B ultrasound was used to assess the posterior pole. The patient underwent pars plana vitrectomy and received intravitreous antibiotics. Results: Vitreous stains and cultures were positive for Enterococcus faecium resistant to vancomycin. Donor rim cultures and viral PCR were negative. Treatment was carried out by repeated intravitreal antibiotics and systemic linezolid. Clinical improvement was seen after the second dose of intravitreous antibiotics and systemic linezolid, but visual acuity remained at light perception consistent with the ischemic changes observed in the posterior pole. Conclusion: VRE endophthalmitis might be associated with positive donor rim cultures. Prompt use of systemic linezolid in addition to intravitreous antibiotics is recommendable, but even with prompt treatment, visual prognosis is guarded.

Transfer of antibiotic resistance from Enterococcus faecium of fermented meat origin to Listeria monocytogenes and Listeria innocua.

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Jahan, M; Holley, R A

2016-04-01

Listeria monocytogenes is an important foodborne pathogen that can cause infection in children, pregnant women, the immunocompromised and the elderly. Antibiotic resistance in this species would represent a significant public health problem since the organism has a high fatality/case ratio and resistance may contribute to failure of therapeutic treatment. This study was designed to explore whether the in vitro transferability of antibiotic resistance from enterococci to Listeria spp. could occur. It was found that 2/8 Listeria strains were able to acquire tetracycline resistance from Enterococcus faecium. Listeria monocytogenes GLM-2 acquired the resistance determinant tet(M) and additional streptomycin resistance through in vitro mating with Ent. faecium S27 isolated from commercial fermented dry sausage. Similarly, Listeria innocua became more resistant to tetracycline, but the genetic basis for this change was not confirmed. It has been suggested that enterococci may transfer antibiotic resistance genes via transposons to Listeria spp., and this may explain, in part, the origin of their antibiotic resistance. Thus, the presence of enterococci in food should not be ignored since they may actively contribute to enhanced antibiotic resistance of L. monocytogenes and other pathogens. Acquisition of antibiotic resistance by pathogenic bacteria in the absence of antibiotic pressure represents an unquantified threat to human health. In the present work resistance to tetracycline and streptomycin were transferred by nonplasmid-based conjugation from Enterococcus faecium isolated from fermented sausage to Listeria monocytogenes and Listeria innocua. Thus, natural transfer of antibiotic resistance to Listeria strains may occur in the future which reinforces the concern about the safety of enterococcal strains present in foods. © 2016 The Society for Applied Microbiology.

Antimicrobial resistance of Enterococcus faecium strains isolated from commercial probiotic products used in cattle and swine.

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Amachawadi, Raghavendra G; Giok, Felicia; Shi, Xiaorong; Soto, Jose; Narayanan, Sanjeev K; Tokach, Mike D; Apley, Mike D; Nagaraja, T G

2018-04-03

Probiotics, an antibiotic alternative, are widely used as feed additives for performance benefits in cattle and swine production systems. Among bacterial species contained in probiotics, Enterococcus faecium is common. Antimicrobial resistance (AMR), particularly multidrug resistance, is a common trait among enterococci because of their propensity to acquire resistance and horizontally transfer AMR genes. Also, E. faecium is an opportunistic pathogen, and in the United States, it is the second most common nosocomial pathogen. There has been no published study on AMR and virulence potential in E. faecium contained in probiotic products used in cattle and swine in the United States. Therefore, our objectives were to determine phenotypic susceptibilities or resistance to antimicrobials, virulence genes (asa1, gelE, cylA, esp, and hyl) and assess genetic diversity of E. faecium isolated from commercial products. Twenty-two commercially available E. faecium-based probiotic products used in cattle (n = 13) and swine (n = 9) were procured and E. faecium was isolated and species confirmed. Antimicrobial susceptibility testing to determine minimum inhibitory concentrations was done by micro-broth dilution method using National Antimicrobial Resistance Monitoring Systems Gram-positive Sensititre panel plate (CMV3AGPF), and categorization of strains as susceptible or resistant was as per Clinical Laboratory and Standards Institute's guidelines. E. faecium strains from 7 products (3 for swine and 4 for cattle) were pan-susceptible to the 16 antimicrobials tested. Strains from 15 products (6 for swine and 9 for cattle) exhibited resistance to at least one antimicrobial and a high proportion of strains was resistant to lincomycin (10/22), followed by tetracycline (4/22), daptomycin (4/22), ciprofloxacin (4/22), kanamycin (3/22), and penicillin (2/22). Four strains were multidrug resistant, with resistant phenotypes ranging from 3 to 6 antimicrobials or class. None of the E

Development of a fluorescent antibody method for the detection of Enterococcus faecium and its potential for coastal aquatic environment monitoring.

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Caruso, Gabriella; Monticelli, L S; Caruso, R; Bergamasco, A

2008-02-01

A direct, microscopic fluorescent antibody method was developed to detect the occurrence of Enterococcus faecium in coastal aquatic environments and was compared with the conventional membrane filtering method. The "in situ" application of the antibody-based protocol in the analysis of water samples collected from coastal polyhaline habitats demonstrated good sensitivity and ease of implementation. Data obtained with the microscopic technique were in agreement with those obtained from culture counts. The fluorescent antibody method proved to be a rapid and reliable technique for the detection of E. faecium. The advantages and limitations intrinsic to the method are discussed, highlighting the potential of this new technique for monitoring coastal aquatic environments.

Effect of Enterococcus faecium EF 55 on morphometry and proliferative activity of intestinal mucosa in broilers infected with Salmonella Enteritidis

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Ševčíková Zuzana

2016-09-01

Full Text Available Introduction: The present study aimed to investigate the effect of Enterococcus faecium EF55 on chickens, as well as its influence on proliferative activity of epithelial intestinal cells after infection with Salmonella enterica serovar Enteritidis phage type 4 (SE PT4. Moreover, the length and area of duodenal and jejunal villi of the birds were examined.

Relationship between copper, glycopeptide, and macrolide resistance among Enterococcus faecium strains isolated from pigs in Denmark between 1997 and 2003

DEFF Research Database (Denmark)

Hasman, Henrik; Aarestrup, Frank Møller

2005-01-01

A significant relationship between copper resistance (tcrB), glycopeptide resistance (Tn1546), and macrolide resistance [erm(B)] in Enterococcus faecium isolated from pigs was found. The tcrB gene was located closely upstream of the Tn1546 element. However, the continued use of copper sulfate has...... not been able to maintain high levels of macrolide and glycopeptide resistance....

High-resolution melting genotyping of Enterococcus faecium based on multilocus sequence typing derived single nucleotide polymorphisms.

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Steven Y C Tong

Full Text Available We have developed a single nucleotide polymorphism (SNP nucleated high-resolution melting (HRM technique to genotype Enterococcus faecium. Eight SNPs were derived from the E. faecium multilocus sequence typing (MLST database and amplified fragments containing these SNPs were interrogated by HRM. We tested the HRM genotyping scheme on 85 E. faecium bloodstream isolates and compared the results with MLST, pulsed-field gel electrophoresis (PFGE and an allele specific real-time PCR (AS kinetic PCR SNP typing method. In silico analysis based on predicted HRM curves according to the G+C content of each fragment for all 567 sequence types (STs in the MLST database together with empiric data from the 85 isolates demonstrated that HRM analysis resolves E. faecium into 231 "melting types" (MelTs and provides a Simpson's Index of Diversity (D of 0.991 with respect to MLST. This is a significant improvement on the AS kinetic PCR SNP typing scheme that resolves 61 SNP types with D of 0.95. The MelTs were concordant with the known ST of the isolates. For the 85 isolates, there were 13 PFGE patterns, 17 STs, 14 MelTs and eight SNP types. There was excellent concordance between PFGE, MLST and MelTs with Adjusted Rand Indices of PFGE to MelT 0.936 and ST to MelT 0.973. In conclusion, this HRM based method appears rapid and reproducible. The results are concordant with MLST and the MLST based population structure.

Colonización por cepas de Enterococcus spp. VanA en pacientes del hospital universitario Manuel Núñez Tovar, Maturín, Venezuela | Colonization by strains of Enterococcus spp. VanA in patients of the university hospital Manuel Núñez Tovar, Maturín, Venezuela

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Lorena Abadia-Patiño

2017-10-01

Full Text Available En el Hospital Universitario Manuel Núñez Tovar de Maturín (HUMNT, estado Monagas, se aislaron tres cepas de Enterococcus faecium VanA en la unidad de cuidados intensivos (UCI y una cepa de E. faecalis VanA en la unidad de hemodiálisis (HD. La prevalencia de colonización de Enterococcus vancomicino resistentes (EVR fenotipo VanA durante el período de estudio fue de 3% en los pacientes de HD y 9% en los de UCI. Los factores de riesgo para los pacientes fueron el uso indiscriminado de antibióticos como vancomicina y cefalosporinas de tercera generación y el tiempo de permanencia en UCI. Existe alto riesgo de infecciones endógenas por cepas EVR en el HUMNT.

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

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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.

High-level heterologous production and functional expression of the sec-dependent enterocin P from Enterococcus faecium P13 in Lactococcus lactis

NARCIS (Netherlands)

Gutierrez, Jorge; Larsen, Rasmus; Cintas, Luis M.; Kok, Jan; Hernandez, Pablo E.

Enterocin P (EntP), a sec-dependent bacteriocin from Enterococcus faecium P13, was produced by Lactococcus lactis. The EntP structural gene (entP) with or without the EntP immunity gene (entiP) was cloned in (1), plasmid pMG36c under control of the lactococcal constitutive promoter P-32, (2) in

Characterization of vancomycin-resistant and vancomycin-susceptible Enterococcus faecium isolates from humans, chickens and pigs by RiboPrinting and pulsed-field gel electrophoresis

DEFF Research Database (Denmark)

Hammerum, Anette Marie; Fussing, Vivian; Aarestrup, Frank Møller

2000-01-01

Forty-eight vancomycin-resistant and 35 vancomycin-sensitive Danish Enterococcus faecium isolates obtained from pigs, chickens and humans, as well as the human vanA reference isolate BM4147, were characterized by EcoRI RiboPrinting and Smal pulsed-field gel electrophoresis. RiboPrinting of the 84...

Pyrosequencing-based comparative genome analysis of the nosocomial pathogen Enterococcus faecium and identification of a large transferable pathogenicity island

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Bonten Marc JM

2010-04-01

Full Text Available Abstract Background The Gram-positive bacterium Enterococcus faecium is an important cause of nosocomial infections in immunocompromized patients. Results We present a pyrosequencing-based comparative genome analysis of seven E. faecium strains that were isolated from various sources. In the genomes of clinical isolates several antibiotic resistance genes were identified, including the vanA transposon that confers resistance to vancomycin in two strains. A functional comparison between E. faecium and the related opportunistic pathogen E. faecalis based on differences in the presence of protein families, revealed divergence in plant carbohydrate metabolic pathways and oxidative stress defense mechanisms. The E. faecium pan-genome was estimated to be essentially unlimited in size, indicating that E. faecium can efficiently acquire and incorporate exogenous DNA in its gene pool. One of the most prominent sources of genomic diversity consists of bacteriophages that have integrated in the genome. The CRISPR-Cas system, which contributes to immunity against bacteriophage infection in prokaryotes, is not present in the sequenced strains. Three sequenced isolates carry the esp gene, which is involved in urinary tract infections and biofilm formation. The esp gene is located on a large pathogenicity island (PAI, which is between 64 and 104 kb in size. Conjugation experiments showed that the entire esp PAI can be transferred horizontally and inserts in a site-specific manner. Conclusions Genes involved in environmental persistence, colonization and virulence can easily be aquired by E. faecium. This will make the development of successful treatment strategies targeted against this organism a challenge for years to come.

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

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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-organismsbiofilms under all tested conditions (counts of the all microorganisms biofilms under all the test conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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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.

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

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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 Acm detected by whole-cell enzyme-linked immunosorbent assay and flow cytometry. Thirty-seven of 41 sera from patients with E. faecium infections showed reactivity with recombinant Acm, while only 4 of 30 community and hospitalized patient control group sera reacted (P Acm were present in all 14 E. 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.

Identification of VanN-type vancomycin resistance in an Enterococcus faecium isolate from chicken meat in Japan.

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Nomura, Takahiro; Tanimoto, Koichi; Shibayama, Keigo; Arakawa, Yoshichika; Fujimoto, Shuhei; Ike, Yasuyoshi; Tomita, Haruyoshi

2012-12-01

Five VanN-type vancomycin-resistant Enterococcus faecium strains were isolated from a sample of domestic chicken meat in Japan. All isolates showed low-level resistance to vancomycin (MIC, 12 mg/liter) and had the same pulsed-field gel electrophoresis profile. The vancomycin resistance was encoded on a large plasmid (160 kbp) and was expressed constitutively. The VanN-type resistance operon was identical to the first resistance operon to be reported, with the exception of a 1-bp deletion in vanT(N) and a 1-bp substitution in vanS(N).

Development of a Chemically Defined Medium for Better Yield and Purification of Enterocin Y31 from Enterococcus faecium Y31

OpenAIRE

Liu, Wenli; Zhang, Lanwei; Yi, Huaxi

2017-01-01

The macro- and micronutrients in traditional medium, such as MRS, used for cultivating lactic acid bacteria, especially for bacteriocin production, have not been defined, preventing the quantitative monitoring of metabolic flux during bacteriocin biosynthesis. To enhance Enterocin Y31 production and simplify steps of separation and purification, we developed a simplified chemically defined medium (SDM) for the growth of Enterococcus faecium Y31 and production of its bacteriocin, Enterocin Y31...

Lactobacillus rhamnosus GG Outcompetes Enterococcus faecium via Mucus-Binding Pili: Evidence for a Novel and Heterospecific Probiotic Mechanism.

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Tytgat, Hanne L P; Douillard, François P; Reunanen, Justus; Rasinkangas, Pia; Hendrickx, Antoni P A; Laine, Pia K; Paulin, Lars; Satokari, Reetta; de Vos, Willem M

2016-10-01

Vancomycin-resistant enterococci (VRE) have become a major nosocomial threat. Enterococcus faecium is of special concern, as it can easily acquire new antibiotic resistances and is an excellent colonizer of the human intestinal tract. Several clinical studies have explored the potential use of beneficial bacteria to weed out opportunistic pathogens. Specifically, the widely studied Lactobacillus rhamnosus strain GG has been applied successfully in the context of VRE infections. Here, we provide new insight into the molecular mechanism underlying the effects of this model probiotic on VRE decolonization. Both clinical VRE isolates and L. rhamnosus GG express pili on their cell walls, which are the key modulators of their highly efficient colonization of the intestinal mucosa. We found that one of the VRE pilus clusters shares considerable sequence similarity with the SpaCBA-SrtC1 pilus cluster of L. rhamnosus GG. Remarkable immunological and functional similarities were discovered between the mucus-binding pili of L. rhamnosus GG and those of the clinical E. faecium strain E1165, which was characterized at the genome level. Moreover, E. faecium strain E1165 bound efficiently to mucus, which may be prevented by the presence of the mucus-binding SpaC protein or antibodies against L. rhamnosus GG or SpaC. These results present experimental support for a novel probiotic mechanism, in which the mucus-binding pili of L. rhamnosus GG prevent the binding of a potential pathogen to the host. Hence, we provide a molecular basis for the further exploitation of L. rhamnosus GG and its pilins for prophylaxis and treatment of VRE infections. Concern about vancomycin-resistant Enterococcus faecium causing nosocomial infections is rising globally. The arsenal of antibiotic strategies to treat these infections is nearly exhausted, and hence, new treatment strategies are urgently needed. Here, we provide molecular evidence to underpin reports of the successful clinical application of

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

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YOUSEF eNAMI

2015-07-01

Full Text Available AbstractScreening of lactic acid bacteria isolated from ewe colostrum led to the identification and isolation of Enterococcus faecium CM33 with interesting features, such as high-survival rates under acidic or bile salt conditions, high tolerance to the simulated gastrointestinal condition, and high adhesive potential to Caco-2 cells. According to the inhibition of pathogen adhesion test results, this strain could 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 the 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 the genes encoding enterocins A, 31, X, and Q were discovered. The findings of this study showed that the strain E. faecium CM33 could be considered a valuable nutraceutical, and it can be introduced as a new potential probiotic.

EL USO DE Enterococcus faecium MEJORA PARÁMETROS PRODUCTIVOS EN POLLOS DE ENGORDE

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L. A. Chavez

2016-01-01

Full Text Available El consumo de probióticos se ha asociado con mejoras en algunos parámetros productivos como la conversión alimenticia y la ganancia de peso vivo, lo que se ve reflejado en el desarrollo y salud de las aves. El objetivo de este trabajo fue evaluar la influencia de la inclusión de cepas probióticas en la alimentación de pollos de engorde sobre parámetros productivos de importancia económica. Se utilizaron 180 pollos machos (Cobb de un día de edad, alimentados con cinco dietas: dieta comercial con y sin la adición de antibióticos, y a esta última se le adicionó una de tres diferentes cepas probióticas (Lactobacillus casei, Lactobacillus acidophilus o Enterococcus faecium en el agua de bebida (108 UFC/ml durante 42 días. Se evaluaron parámetros zootécnicos: consumo de alimento, peso corporal, conversón alimenticia (CA y ganancia de peso (GDP; e indicadores productivos: supervivencia, factor de eficiencia americana (FEA, índice productivo (IP, eficiencia europea (EE y eficiencia alimenticia (EA. El diseño estadístico utilizado fue de bloques al azar. La inclusión de probióticos, específicamente E. faecium, mejoró parámetros productivos (P < 0,05 como peso (2.730 g, conversión (1,55, GDP (53,59 g/día, FEA (172, IP (393, EE (400 y EA (63,11%. Por todo lo anterior, la utilización de probióticos, especialmente E. faecium, puede ser considerada como factor promotor de crecimiento durante todo el ciclo de producción del ave debido a que demostró tener efectos positivos, tanto en el desempeño productivo, como en el rendimiento económico del lote.

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

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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.

Endocarditis due to vancomycin-resistant Enterococcus raffinosus successfully treated with linezolid: case report and review of literature Endocarditis por Enterococcus raffinosus resistente a vancomicina exitosamente tratada con linezolid: caso clínico y revisión de la literatura

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A. Jasovich

2008-12-01

Full Text Available Enterococcus raffinosus is scarcely found in clinical samples and even less frequently as etiologic agent of endocarditis. We are herein presenting one case of mitral prosthetic-valve endocarditis in a 77-y-o male due to a vancomycinresistant Enterococcus raffinosus isolate, successfully treated with 6 weeks of linezolid, and a two-year follow up.Enterococcus raffinosus es una especie poco frecuente en materiales clínicos y menos aún como agente etiológico de endocarditis. En este trabajo se presenta un caso de endocarditis de válvula mitral protésica en un paciente de 77 años debida a Enterococcus raffinosus resistente a vancomicina y que fue exitosamente tratada con linezolid durante 6 semanas, con un seguimiento de 2 años.

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.

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

2012-08-01

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.

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

DEFF Research Database (Denmark)

Freitas, Ana R.; Coque, Teresa M.; Novais, Carla

2011-01-01

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 (rep(pLG1)). E. faecium CC17 (ST132) isolates from pig manure and two clinical samples showed identical PFGE profiles and contained a 60-kb mosaic plasmid (rep(Inc18) plus rep...

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

Science.gov (United States)

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.

In Vitro Synergy of Telavancin and Rifampin Against Enterococcus faecium Resistant to Both Linezolid and Vancomycin.

Science.gov (United States)

Pankey, George A; Ashcraft, Deborah S

2013-01-01

An emerging pathogen is Enterococcus faecium resistant to both linezolid and vancomycin (LRVRE). Antimicrobial combinations may be required for therapy and need to be evaluated. The combination of daptomycin and rifampin has demonstrated good in vitro activity against gram-positive bacteria, including E faecium. Telavancin, a newer lipoglycopeptide, has shown in vitro activity against E faecium. We evaluated the combination of telavancin and rifampin and compared the results to the combination of daptomycin and rifampin used previously on the same isolates. Twenty-four genetically unique (by pulsed-field gel electrophoresis), clinical LRVRE isolates were collected in the United States from 2001-2004. Etest minimal inhibitory concentrations (MICs) (μg/mL) were 0.064-8 for telavancin, 1-4 for daptomycin, and 0.012 to >32 for rifampin. In vitro synergy testing was performed in triplicate by an Etest MIC:MIC ratio method, and summation fractional inhibitory concentration (ΣFIC) was calculated: synergy ≤0.5; indifference >0.5-4; and antagonism >4. The Etest method showed synergy (ΣFICs of 0.1-0.5) with telavancin + rifampin in 20/24 (83%) isolates and indifference (ΣFICs of 0.6-0.8) in 4/24 (17%) isolates. Similarly, the daptomycin + rifampin combination showed synergy (ΣFICs of 0.1-0.5) in 21/24 (88%) isolates and indifference (ΣFICs of 0.6-1.0) in 3/24 (12%) isolates by the Etest method. No antagonism was found. In vitro synergy with both combinations (rifampin + telavancin or daptomycin) was 83% and 88%, respectively, by Etest against these LRVRE isolates. Although both daptomycin and telavancin in combination with rifampin showed a high incidence of synergistic activity, further in vitro synergy testing with this combination should be performed against additional E faecium isolates. In vitro synergy may or may not translate into in vivo effectiveness.

Efficacy of Tigecycline Alone and in Combination with Gentamicin in the Treatment of Experimental Endocarditis Due to Linezolid-Resistant Enterococcus faecium

OpenAIRE

Pontikis, Konstantinos; Pefanis, Angelos; Tsaganos, Thomas; Tzepi, Ira-Maria; Carrer, Dionyssia-Pinelopi; Giamarellou, Helen

2013-01-01

We evaluated the efficacy of tigecycline in a rabbit model of experimental endocarditis caused by a linezolid-resistant clinical strain of Enterococcus faecium. Tigecycline-treated animals had a 2.8-log10-CFU/g reduction in microbial counts in excised vegetations compared with controls. Addition of gentamicin caused a further arithmetical reduction in colony counts. The therapeutic effect was sustained 5 days after completion of treatment, as shown by relapse studies performed in treatment gr...

Efficacy of tigecycline alone and in combination with gentamicin in the treatment of experimental endocarditis due to linezolid-resistant Enterococcus faecium.

Science.gov (United States)

Pontikis, Konstantinos; Pefanis, Angelos; Tsaganos, Thomas; Tzepi, Ira-Maria; Carrer, Dionyssia-Pinelopi; Giamarellou, Helen

2013-07-01

We evaluated the efficacy of tigecycline in a rabbit model of experimental endocarditis caused by a linezolid-resistant clinical strain of Enterococcus faecium. Tigecycline-treated animals had a 2.8-log10-CFU/g reduction in microbial counts in excised vegetations compared with controls. Addition of gentamicin caused a further arithmetical reduction in colony counts. The therapeutic effect was sustained 5 days after completion of treatment, as shown by relapse studies performed in treatment groups.

A Novel High-Molecular-Mass Bacteriocin Produced by Enterococcus faecium: Biochemical Features and Mode of Action.

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Vasilchenko, A S; Vasilchenko, A V; Valyshev, A V; Rogozhin, E A

2018-02-08

Discovery of a novel bacteriocin is always an event in sciences, since cultivation of most bacterial species is a general problem in microbiology. This statement is reflected by the fact that number of bacteriocins is smaller for tenfold comparing to known antimicrobial peptides. We cultivated Enterococcus faecium on simplified medium to reduce amount of purification steps. This approach allows to purify the novel heavy weight bacteriocin produced by E. faecium ICIS 7. The novelty of this bacteriocin, named enterocin-7, was confirmed by N-terminal sequencing and by comparing the structural-functional properties with available data. Purified enterocin-7 is characterized by a sequence of amino acid residues having no homology in UniProt/SwissProt/TrEMBL databases: NH2 - Asp - Ala - His - Leu - Ser - Glu - Val - Ala - Glu - Arg - Phe - Glu - Asp - Leu - Gly. Isolated thermostable protein has a molecular mass of 65 kDa, which allows it to be classified into class III in bacteriocin classification schemes. Enterocin-7 displayed a broad spectrum of activity against some Gram-positive and Gram-negative microorganisms. Fluorescent microscopy and spectroscopy showed the permeabilizing mechanism of the action of enterocin-7, which is realized within a few minutes.

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

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Honsa, Erin S; Cooper, Vaughn S; Mhaissen, Mohammed N; Frank, Matthew; Shaker, Jessica; Iverson, Amy; Rubnitz, Jeffrey; Hayden, Randall T; Lee, Richard E; Rock, Charles O; Tuomanen, Elaine I; Wolf, Joshua; Rosch, Jason W

2017-01-03

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. The increasing prevalence of antibiotic-resistant bacterial pathogens is a major challenge currently facing the medical community. Such pathogens are of particular importance in immunocompromised patients as these individuals may favor emergence of novel resistance determinants due to lack of innate immune defenses and intensive antibiotic exposure. During the course of chemotherapy, a patient developed prolonged bacteremia with vancomycin-resistant Enterococcus faecium that failed to clear

Optimization of conditions for probiotic curd formulation by Enterococcus faecium MTCC 5695 with probiotic properties using response surface methodology.

Science.gov (United States)

Ramakrishnan, Vrinda; Goveas, Louella Concepta; Prakash, Maya; Halami, Prakash M; Narayan, Bhaskar

2014-11-01

Enterococcus faecium MTCC 5695 possessing potential probiotic properties as well as enterocin producing ability was used as starter culture. Effect of time (12-24 h) and inoculum level (3-7 % v/v) on cell growth, bacteriocin production, antioxidant property, titrable acidity and pH of curd was studied by response surface methodology (RSM). The optimized conditions were 26.48 h and 2.17%v/v inoculum and the second order model validated. Co cultivation studies revealed that the formulated product had the ability to prevent growth of foodborne pathogens that affect keeping quality of the product during storage. The results indicated that application of E. faecium MTCC 5695 along with usage of optimized conditions attributed to the formation of highly consistent well set curd with bioactive and bioprotective properties. Formulated curd with potential probiotic attributes can be used as therapeutic agent for the treatment of foodborne diseases like Traveler's diarrhea and gastroenteritis which thereby help in improvement of bowel health.

Approaches for enhancing in situ detection of enterocin genes in thermized milk, and selective isolation of enterocin-producing Enterococcus faecium from Baird-Parker agar.

Science.gov (United States)

Vandera, Elpiniki; Tsirka, Georgia; Kakouri, Athanasia; Koukkou, Anna-Irini; Samelis, John

2018-05-21

Enterococci are naturally selected for growth in thermized ewes'/goats' milk mixtures used for traditional cooked hard cheese processing in Greece. A culture-independent PCR-based approach was applied to detect the presence of enterocin-encoding genes in naturally culture-enriched thermized milk (TM). Portions of TM (63 °C, 30 s) collected from a commercial cheese plant before addition of starters were fermented at 37 °C for 48 h to facilitate growth of indigenous enterococci. The multiple enterocin-producing (m-Ent+) Enterococcus faecium KE82 and the nisin A-producing Lactococcus lactis subsp. cremoris M104 served as bacteriocin-positive inocula in separate TM treatments. The PCR results revealed a constant presence of the enterocin A, B and P genes in TM fermented naturally at 37 °C. Eleven out of 42 (26.2%) lactic isolates from the enriched TM cultures without inoculation were Ent+ E. faecium assigned to three biotypes. Biotype I (4 isolates) included single entA possessors, whereas biotype II (5 isolates) and biotype III (2 isolates) were m-Ent+ variants profiling entA-entB-entP and entA-entB genes, respectively. Biotype II displayed the strongest antilisterial activity in vitro. Surprisingly, 85.7% (6/7) of the m-Ent+ E. faecium were selectively isolated from Baird-Parker agar, reflecting their natural resistance to 0.01% tellurite contained in the egg yolk supplement. No cytolysin-positive E. faecalis or other Ent+ Enterococcus spp. were isolated. In conclusion, commercially thermized Greek milk is a natural pool or 'reservoir' of antagonistic Ent+ or m-Ent+ E. faecium strains that can be easily detected and recovered by applying this PCR-based approach to naturally fermented milks or cheese products. Copyright © 2018 Elsevier B.V. All rights reserved.

Association between the use of avilamycin for growth promotion and the occurrence of resistance among Enterococcus faecium from broilers: Epidemiological study and changes over time

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Bager, Flemming; Andersen, J. S.

2000-01-01

This study describes the changes in the occurrence of resistance to avilamycin among Enterococcus faecium from broilers in Denmark and the epidemiological association between usage of avilamycin for growth promotion and the occurrence of avilamycin-resistant E, faecium on broiler farms....... The consumption of avilamycin for growth promotion increased from 10 kg in 1990 to 2,740 kg 1996 and decreased in the following years to only 7 kg in 1998, Most of this has been used for broilers. As part of the nationwide monitoring program for antimicrobial resistance, a total of 473 E, faecium isolates from...... broilers and 290 isolates from pigs have been tested for their susceptibility to avilamycin from 1995 to 1998, A very limited number of isolates from pigs were resistant to avilamycin, whereas the occurrence of resistance among isolates from broilers increased from 63.6% at the end of 1995 to a maximum...

Purification of a Novel Bacteriocin-Like Inhibitory Substance Produced by Enterococcus faecium ICIS 8 and Characterization of Its Mode of Action.

Science.gov (United States)

Vasilchenko, Alexey S; Rogozhin, Eugene A; Valyshev, Alexander V

2017-06-01

The aim of this work was to purify and characterize a bacteriocin-like antimicrobial substance produced by an antagonistic active strain of Enterococcus faecium. A novel bacteriocin-like inhibitory substance (BLIS) produced by the E. faecium ICIS 8 strain was purified and characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and N-terminal amino acid sequencing revealed the following partial sequence: NH 2 -APKEKCFPKYCV. The proteinaceous nature of purified BLIS was assessed by treatment with proteolytic enzyme. Studies of the action of BLIS using bacteriological and bioluminescence assays revealed a dose-dependent inhibition of Listeria monocytogenes 88BK and Escherichia coli K12 TG1 lac::lux viability. The interaction of the BLIS with the bacterial surface led to the compensation of a negative charge value, as shown by zeta-potential measurements. Assessments of membrane integrity using fluorescent probes and atomic force microscopy revealed the permeabilization of the cellular barrier structures in both L. monocytogenes and E. coli. The novel BLIS from E. faecium ICIS 8 was characterized by a unique primary peptide sequence and exerted bactericidal activity against L. monocytogenes and E. coli by disrupting membrane integrity.

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

Science.gov (United States)

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

Ampicillin-resistant Enterococcus faecium : ecology, transmission dynamics and intervention strategies

NARCIS (Netherlands)

de Regt, M.J.A.

2010-01-01

For years, E. faecium only sporadically caused opportunistic infections in humans and was considered a relatively harmless commensal. In the last two decades, however, a specific polyclonal E. faecium subpopulation has rapidly become a prominent cause of nosocomial infections, which are often

Enterococcus faecium as a Salmonella surrogate in the thermal processing of wheat flour: Influence of water activity at high temperatures.

Science.gov (United States)

Liu, Shuxiang; Rojas, Rossana V; Gray, Peter; Zhu, Mei-Jun; Tang, Juming

2018-09-01

This study investigated the influence of temperature-dependent water activity (a w ) on thermal resistances of Enterococcus faecium NRRL B-2354 (E. faecium) and Salmonella Enteritidis PT 30 (S. Enteritidis) in wheat flour. The a w for wheat flour samples at 20, 40, and 60 °C was determined by a vapor sorption analyzer and at 75, 80 and 85 °C using custom-built thermal cells with high temperature humidity sensors. Full-factorial isothermal inactivation studies of both strains in sealed aluminum-test-cells included three temperatures (75, 80, and 85 °C) and three a w,25°C levels (0.30, 0.45 and 0.60 within ±0.02 range, prior to the thermal treatments). Isotherm results of wheat flour demonstrate a significant increase (P processing of wheat flour for control of Salmonella over a moisture content of 10-14% and treatment temperatures between 75 and 85 °C. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

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Dalia Moemen

2015-09-01

Full Text Available 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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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

Bacteriocinogenic potential and virulence traits of Enterococcus faecium and E. faecalis isolated from human milk

Science.gov (United States)

Khalkhali, Soodabeh; Mojgani, Naheed

2017-01-01

Background and Objectives: Human milk is a continuous supply of Lactic Acid bacteria (LAB), including enterococci with probiotic potentials. The aim of this study was to analyze two Enterococcus species, isolated from human milk for their probiotic potential, bacteriocin producing ability and virulence traits. Materials and Methods: Enterococcus faecium TA0033 and E. faecalis TA102 were tested for acid and bile tolerance, survival in simulated gastric and intestinal conditions. The antibacterial spectrum of the isolates was tested by agar well diffusion assay. The antagonistic agent was characterized by physico-chemical methods. The enterocin structural genes, virulence determinants, vancomycin resistance and biogenic amine genes, such as hdc1, hdc2, tdc, ldc and odc were also determined. Results: The tested isolates survived acidic conditions, high bile salt (1%), simulated gastric and intestinal conditions. The culture supernatant fluids of the two isolates inhibited the growth of Escherichia coli, Listeria monocytogenes, Salmonella typhi, Staphylococcus aureus, Shigella dysenteriae and Streptococcus agalactiae. The antagonistic activity was lost in the presence of proteolytic enzymes but tolerated the action of catalase, lysozyme and lipase. In contrast to enterocin TA102, enterocin TA0033 possessed bactericidal mode of action. Bacteriocin structural genes, entA and entB were present in the genome of the two isolates, while E. faecalis TA102 additionally harboured entP and bac31 genes. The phenotypic and genotypic virulence assessment studies indicated hyaluronidase (hyl) production and vancomycin resistance in E. faecalis TA102 while, none of the isolates harboured the biogenic amine genes. Conclusion: The presence of virulence genes in E. faecalis TA102 calls for careful monitoring of Enterococcus isolates for their safety parameters. PMID:29238458

Identification of Structural and Immunity Genes of a Class IIb Bacteriocin Encoded in the Enterocin A Operon of Enterococcus faecium Strain MXVK29.

Science.gov (United States)

Escamilla-Martínez, E E; Cisneros, Y M Álvarez; Fernández, F J; Quirasco-Baruch, M; Ponce-Alquicira, E

2017-10-09

The Enterococcus faecium strain MXVK29, isolated from fermented sausages, produces a bacteriocin with a molecular mass of 3.5 kDa that belongs to the class of enterocins II.1, according to the terminal amino acid sequence, and has been identified as enterocin A. This bacteriocin is active against selected strains of Listeria, Staphylococcus, Pediococcus, and Enterococcus. In this study, we identified the genes adjacent to the structural gene for this bacteriocin, such as the immunity gene (entI) and the inducer gene (entF). Accessory genes for this bacteriocin, such as entK, entR, and entT, were identified as well, in addition to the orf2 and orf3, showing a high identity with class IIb peptides bacteriocins. The orf2 shows the consensus motif GxxxG, similar to those shown by bacteriocins such as PlnNC8α, EntCα, and Ent1071A, whereas orf3 shows a consensus motif SxxxS similar to that present in PlnNC8β (AxxxA). PlnNC8 is expressed only in bacterial cocultures, so there is the possibility that the expression of this two-peptide bacteriocin can be induced by a similar mechanism. So far, only the expression of enterocin A has been found in this strain; however, the presence of the genes ent29α and ent29β opens the possibility for further research on its induction, functionality, and origin. Although there are reports on this type of bacteriocin (EntX, EntC, and Ent1071) in other strains of E. faecium, no report exists yet on an Enterococcus strain producing two different classes of bacteriocin.

Enhanced Control of Listeria monocytogenes by Enterococcus faecium KE82, a Multiple Enterocin-Producing Strain, in Different Milk Environments.

Science.gov (United States)

Vandera, Elpiniki; Lianou, Alexandra; Kakouri, Athanasia; Feng, Jinbo; Koukkou, Anna-Irini; Samelis, John

2017-01-01

Enterococcus faecium KE82, isolated from traditional Greek Graviera cheese, was identified in pure broth cultures in vitro as a multiple enterocin-producing bacterial strain possessing the structural entA, entB, and entP enterocin genes. E. faecium KE82 was further assessed for in situ antilisterial activity in raw milk (RM) and commercially thermized milk (TM; 63°C for 30 s) in the presence of the indigenous microbiota and in sterile raw milk (SRM; 121°C for 5 min) with or without the addition of two commercial starter culture (CSC) strains Streptococcus thermophilus and Lactococcus lactis . Growth of Listeria monocytogenes was completely inhibited in RM incubated at 37°C for 6 h, whereas the pathogen was significantly inactivated in RM+KE82 samples during further incubation at 18°C for 66 h. In contrast, L. monocytogenes levels increased by approximately 2 log CFU/ml in TM, but in TM+KE82 samples, pathogen growth was retarded during the first 6 h at 37°C followed by growth cessation and partial inactivation at 18°C. After 48 to 72 h, growth of L. monocytogenes in SRM+CSC samples decreased by 4 to 5 log CFU/ml compared with the SRM control, whereas additional 10-fold decreases in the pathogen were observed in SRM+CSC+KE82 samples. Reverse transcription PCR analysis of SRM+KE82 and SRM+CSC+KE82 samples confirmed that the entA and entB genes were transcribed, but entP gene transcription was not detected. All RM and SRM samples inoculated with E. faecium KE82 displayed strong in situ inhibitory activity against L. monocytogenes in well diffusion bioassays, whereas activity was weaker to undetectable in comparable or additional TM+KE82 samples; no milk sample without E. faecium KE82 had activity against L. monocytogenes . The findings of this study indicate that E. faecium KE82 is an antilisterial agent that could be used in traditional dairy foods because it concomitantly produces enterocins A and B in situ in milk.

Características de α−acetolactato sintetasa y producción de diacetilo por Enterococcus faecium ETw7 y Enterococcus faecalis ETw23

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Marisol Vallejo

2013-03-01

Full Text Available El diacetilo es un compuesto aromático esencial en productos lácteos fermentados como el queso. En este trabajo se estudiaron características cinéticas y bioquímicas de la α-acetolactato sintetasa (α-ALS y su influencia en la producción de diacetilo en Enterococcus faecium ETw7 y Enteroccoccus faecalis ETw23. En ambos casos, los parámetros cinéticos revelaron una baja afinidad por el piruvato, como ha sido descrito en otras bacterias ácido lácticas. E. faecium ETw7 desarrolló la máxima actividad enzimática a pH 5,8—6,2 y 40 ºC, sin embargo bajo las condiciones de maduración de quesos (pH 5,0 y 15 oC la actividad remanente fue baja. La α-ALS de E. faecalis ETw23 mostró la máxima actividad al pH de maduración, la temperatura óptima fue determinada a 40 ºC y la actividad remanente a 15 ºC fue aproximadamente el 30% de la máxima. El crecimiento y la producción de diacetilo fue estudiada en el medio De Man-Rogosa-Sharpe (MRS y MRS suplementado con citrato (MRScit. La tasa de crecimiento de E. faecium ETw7 fue comparable en ambos medios, pero se observó un aumento de la biomasa en MRScit. En el caso de E. faecalis ETw23 se logró una mayor tasa de crecimiento entre las 6 y 10 h, y una mayor biomasa en MRScit. Después de 24 h de crecimiento E. faecium ETw7 alcanzó un nivel de 20,4 μM de diacetilo en MRS y 26,1 μM en MRScit, mientras que E. faecalis ETw23 logró niveles de 41,8 μM y 61,7 μM, respectivamente. Los resultados de este estudio sugieren que E. faecalis ETw23 puede contribuir en el desarrollo de aromas en quesos a través de su rol en la producción de diacetilo.

Microencapsulation increases survival of the probiotic Lactobacillus plantarum IS-10506, but not Enterococcus faecium IS-27526 in a dynamic, computer-controlled in vitro model of the upper gastrointestinal tract.

Science.gov (United States)

Surono, I; Verhoeven, J; Verbruggen, S; Venema, K

2018-02-23

To test the effect of microencapsulation on the survival of two probiotic strains isolated from Dadih, Indonesian fermented buffalo milk, in a dynamic, computer-controlled in vitro model of the upper gastrointestinal (GI) tract (TIM-1), simulating human adults. Free or microencapsulated probiotics, Lactobacillus plantarum IS-10506 or Enterococcus faecium IS-27526, resuspended in milk were studied for survival in the complete TIM-1 system (stomach + small intestine) or in the gastric compartment of TIM-1 only. Hourly samples collected after the ileal-caecal valve or after the pylorus were plated on MRS agar (for Lactobacillus) or S&B agar (for Enterococcus). Survival of the free cells after transit through the complete TIM-1 system was on average for the E. faecium and L. plantarum 15·0 and 18·5% respectively. Survival of the microencapsulated E. faecium and L. plantarum was 15·7 and 84·5% respectively. The free cells were further assessed in only the gastric compartment of TIM-1. E. faecium and L. plantarum showed an average survival of 39 and 32%, respectively, after gastric passage. There is similar sensitivity to gastric acid as well as survival after complete upper GI tract transit of free cells, but microencapsulation only protected L. plantarum. Survival of microencapsulated L. plantarum IS-10506 is increased compared to free cells in a validated in vitro model of the upper GI tract. It increases its use as an ingredient of functional foods. © 2018 The Society for Applied Microbiology.

Enterococcus faecium F58, a bacteriocinogenic strain naturally occurring in Jben, a soft, farmhouse goat's cheese made in Morocco.

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Achemchem, F; Martínez-Bueno, M; Abrini, J; Valdivia, E; Maqueda, M

2005-01-01

Characterization of Ent F-58 produced by Enterococcus faecium strain F58 isolated from Jben, a soft, farmhouse goat's cheese manufactured without starter cultures. E. faecium strain F58 was isolated because of its broad inhibitory spectrum, including activity against food-borne pathogenic and spoilage bacteria. The antimicrobial substance was produced during the growth phase, with maximum production after 16-20 h of incubation at 30 degrees C, and was stable over a wide pH range (4-8) and at high temperatures (5 min at 100 degrees C). The enterocin was purified to homogeneity using cation exchange and hydrophobic interaction on C-18 and reverse-phase high-performance liquid chromatography. The activity was eluted as two individual active fractions (F-58A and F-58B) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis showed masses of 5210.5 and 5234.3 Da respectively. Both peptides were partially sequenced by Edman degradation, and amino-acid sequencing revealed high similarity with enterocin L50 (I). PCR-amplified fragments containing the structural genes for F-58 A and B were located in a 22-kb plasmid harboured by this strain. We verified that it also holds the structural gene for P-like enterocin. E. faecium strain F58 from Jben cheese, a producer of enterocin L50, exerts an inhibitory effect against strains of genera such as Listeria, Staphylococcus, Clostridium, Brochothrix and Bacillus. Enterocin was characterized according to its functional and biological properties, purification to homogeneity and an analysis of its amino acid and genetic sequences. E. faecium strain F58 is a newly discovered producer of enterocin L50, the biotechnological characteristics of which indicate its potential for application as a protective agent against pathogens and spoilage bacteria in foods.

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

Science.gov (United States)

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

Screening of Lactic Acid Bacteria Isolated from Iranian sourdoughs for Antifungal Activity: Enterococcus faecium showed the Most Potent Antifungal Activity in Bread

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Alam Taghi-Zadeh

2017-09-01

Full Text Available Background and Objective: The use of antifungal lactic acid bacteria as starter for bread making could be a good alternative to improve the stability of bread shelf life.Material and Methods: In this study, a total of 57 lactic acid bacteria were isolated from spontaneously fermented wheat sourdoughs collected in Chahar-Mahalo Bakhryari province of Iran. The isolates were screened for in vitro antifungal activity (towards Aspergilus niger or Penicillium roqueforti; and the selected isolates (six isolates were applied in flat bread making. The freshly baked breads were nebulized with a suspension of either molds, containing 104 spores ml-1, and the fungal growth on breads was monitored over a 7-day storage period.Results and Conclusion: Bread produced with either isolates AN3 and MB1 (both were identified as Enterococcus faecium restrained the growth of Aspergillus niger for up to 5 days. Even though none of the isolates were strong enough to inhibit the growth of Penicillium roquforti on bread, the surface area of breads contaminated by this fungus was significantly lower than the control samples. To our knowledge, it was the first report indicating the anti-mold activity of Enterococcus faecium strains isolated from sourdough. These isolates seem to be promising for further analysis and their application in bread industry for prolonging the shelf life.Conflict of interest: The authors declare that there is no conflict of interest.

Bacteriocidal activity of sanitizers against Enterococcus faecium attached to stainless steel as determined by plate count and impedance methods.

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Andrade, N J; Bridgeman, T A; Zottola, E A

1998-07-01

Enterococcus faecium attached to stainless steel chips (100 mm2) was treated with the following sanitizers: sodium hypochlorite, peracetic acid (PA), peracetic acid plus an organic acid (PAS), quaternary ammonium, organic acid, and anionic acid. The effectiveness of sanitizer solutions on planktonic cells (not attached) was evaluated by the Association of Official Analytical Chemists (AOAC) suspension test. The number of attached cells was determined by impedance measurement and plate count method after vortexing. The decimal reduction (DR) in numbers of the E. faecium population was determined for the three methods and was analyzed by analysis of variance (P plate count method after vortexing, and impedance measurement, respectively. Plate count and impedance methods showed a difference (P measurement was the best method to measure adherent cells. Impedance measurement required the development of a quadratic regression. The equation developed from 82 samples is as follows: log CFU/chip = 0.2385T2-0.96T + 9.35, r2 = 0.92, P plate count method after vortexing. These data suggest that impedance measurement is the method of choice when evaluating the number of bacterial cells adhered to a surface.

Tedizolid susceptibility in linezolid- and vancomycin-resistant Enterococcus faecium isolates.

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Klupp, E-M; Both, A; Belmar Campos, C; Büttner, H; König, C; Christopeit, M; Christner, M; Aepfelbacher, M; Rohde, H

2016-12-01

Vancomycin-resistant enterococci (VRE) are of ever-increasing importance, most notably in high-risk patient populations. Therapy options are often limited for these isolates, and apart from tigecycline and daptomycin, oxazolidinone linezolid is frequently administered. The broad usage of linezolid, however, has driven the emergence of linezolid-resistant VRE strains (LR-VRE), further shortening therapeutic options. Second-generation oxazolidinone tedizolid has the advantage of being active against a specific subset of LR-VRE, i.e. isolates expressing the plasmid-encoded chloramphenicol-florfenicol resistance (cfr) gene. Here we tested tedizolid activity in a collection of 30 LR Enterococcus faecium VRE (MIC range 32-256 mg/l) isolated between 2012 and 2015 from clinical and screening specimens. By pulsed field gel electrophoresis (PFGE) isolates were assigned to 16 clonal lineages. In three cases, linezolid-susceptible progenitor isolates of LR-VRE were isolated, thus demonstrating the de-novo emergence of the linezolid-resistant phenotype. PCR did not detect cfr, cfr(B) or novel oxazolidinone resistance gene optrA in LR-VRE. All isolates, however, carried mutations within the 23S rDNA. Compared to linezolid, tedizolid MICs were lower in all isolates (MIC range 2-32 mg/l), but remained above the FDA tedizolid breakpoint for E. faecalis at 0.5 mg/l. Thus, related to the predominant resistance mechanism, tedizolid is of limited value for treatment of most LR-VRE and represents a therapeutic option only for a limited subset of isolates.

The current MLVA typing scheme for Enterococcus faecium is less discriminatory than MLST and PFGE for epidemic-virulent, hospital-adapted clonal types

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Klare Ingo

2007-04-01

Full Text Available Abstract Background MLVA (multiple-locus variable-number tandem repeat analysis is a reliable typing technique introduced recently to differentiate also isolates of Enterococcus faecium. We used the established VNTR (variable number of tandem repeats scheme to test its suitability to differentiate 58 E. faecium isolates representing mainly outbreaks and clusters of infections and colonizations among patients from 31 German hospitals. All isolates were vancomycin-resistant (vanA type. Typing results for MLVA are compared with results of macrorestriction analysis in PFGE (pulsed-field gel electrophoresis and MLST (multi-locus sequence typing. Results All 51 but one hospital isolates from 1996–2006 were assigned to the clonal complex (CC of epidemic-virulent, hospital-adapted lineages (MLST CC-17; MLVA CC-1 and differed from isolates of sporadic infections and colonizations (n = 7; 1991–1995 and other non-hospital origins (n = 27. Typing of all 58 hospital VRE revealed MLVA as the least discriminatory method (Simpson's diversity index 0.847 when compared to MLST (0.911 and PFGE (0.976. The two most common MLVA types MT-1 (n = 16 and MT-159 (n = 14 combined isolates of several MLST types including also major epidemic, hospital-adapted, clonal types (MT-1: ST-17, ST-18, ST-280, ST-282; MT-159: ST-78, ST-192, ST-203. These data clearly indicate that non-related E. faecium could possess an identical MLVA type being especially critical when MLVA is used to elucidate supposed outbreaks with E. faecium within a single or among different hospitals. Stability of a given MLVA profile MT-12 (ST-117 during an outbreak over a period of five years was also shown. Conclusion MLVA is a suitable method to assign isolates of E. faecium into distinct clonal complexes. To investigate outbreaks the current MLVA typing scheme for E. faecium does not discriminate enough and cannot be recommended as a standard superior to PFGE.

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.

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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

Physical, biochemical and genetic characterization of enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from Thai indigenous chicken intestinal tract

OpenAIRE

Kraiyot Saelim; Sireewan Kaewsuwan; Akio Tani; Suppasil Maneerat

2015-01-01

Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decr...

Purification and characterization of multiple bacteriocins and an inducing peptide produced by Enterococcus faecium NKR-5-3 from Thai fermented fish.

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Ishibashi, Naoki; Himeno, Kohei; Fujita, Koji; Masuda, Yoshimitsu; Perez, Rodney Honrada; Zendo, Takeshi; Wilaipun, Pongtep; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji

2012-01-01

Enterocins NKR-5-3A, B, C, and D were purified from the culture supernatant of Enterococcus faecium NKR-5-3 and characterized. Among the four purified peptides, enterocin NKR-5-3A (5242.3 Da) was identical to brochocin A, produced by Brochothrix campestris ATCC 43754, in mature peptides, and its putative synergistic peptide, enterocin NKR-5-3Z, was found to be encoded in ent53Z downstream of ent53A, encoding enterocin NKR-5-3A. Enterocin NKR-5-3B (6316.4 Da) showed a broad antimicrobial spectrum, and enterocin NKR-5-3C (4512.8 Da) showed high activity against Listeria. Enterocin NKR-5-3D (2843.5 Da), showing high homology to an inducing peptide produced by Lactobacillus sakei 5, induced the production of the enterocins. The enterocins showed different antimicrobial spectra and intensities. E. faecium NKR-5-3 concomitantly produced enterocins NKR-5-3A, B, C, and D which probably belong to different classes of bacteriocins. Furthermore, NKR-5-3 production was induced by enterocin NKR-5-3D.

Shape-dependent antibacterial activity of silver nanoparticles on Escherichia coli and Enterococcus faecium bacterium

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Alshareef, A.; Laird, K.; Cross, R. B. M.

2017-12-01

Silver nanoparticles (AgNPs) have been shown to exhibit strong antibacterial activity against both Gram-positive bacteria and Gram-negative bacteria including antibiotic resistant strains. This study aims to compare the bactericidal effect of different shaped AgNPs (spherical and truncated octahedral) against Escherichia coli and Enterococcus faecium. The antimicrobial activity of a range of concentrations (50, 100, 1000 μg/ml) was determined over 24 h using both optical density and viable counts. Truncated octahedral AgNPs (AgNOct) were found to be more active when compared with spherical AgNPs (AgNS). The difference in shape resulted in differences in efficacy which may be due to the higher surface area of AgNOct compared to AgNS, and differences in active facets and surface energies, with AgNPs having a bacteriostatic effect and AgNOct being bactericidal after 4 h. The results suggest that AgNPs can be used as effective growth inhibitors in different microorganisms, rendering them applicable to various medical devices and antimicrobial control systems.

Engineering the l-Arabinose Isomerase from Enterococcus Faecium for d-Tagatose Synthesis.

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de Sousa, Marylane; Manzo, Ricardo M; García, José L; Mammarella, Enrique J; Gonçalves, Luciana R B; Pessela, Benevides C

2017-12-06

l-Arabinose isomerase (EC 5.3.1.4) (l-AI) from Enterococcus faecium DBFIQ E36 was overproduced in Escherichia coli by designing a codon-optimized synthetic araA gene. Using this optimized gene, two N- and C-terminal His-tagged-l-AI proteins were produced. The cloning of the two chimeric genes into regulated expression vectors resulted in the production of high amounts of recombinant N -His-l-AI and C -His-l-AI in soluble and active forms. Both His-tagged enzymes were purified in a single step through metal-affinity chromatography and showed different kinetic and structural characteristics. Analytical ultracentrifugation revealed that C -His-l-AI was preferentially hexameric in solution, whereas N -His-l-AI was mainly monomeric. The specific activity of the N -His-l-AI at acidic pH was higher than that of C -His-l-AI and showed a maximum bioconversion yield of 26% at 50 °C for d-tagatose biosynthesis, with Km and Vmax parameters of 252 mM and 0.092 U mg -1 , respectively. However, C -His-l-AI was more active and stable at alkaline pH than N -His-l-AI. N -His-l-AI follows a Michaelis-Menten kinetic, whereas C -His-l-AI fitted to a sigmoidal saturation curve.

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.

Science.gov (United States)

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, Zn(high); 50 ppm, Zn(low)). 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 Zn(high) and E. faecium groups gained weight after infection while those in the control group (Zn(low)) 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 Zn(high)+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 Zn(high) and E. faecium groups at single time points after infection compared to the Zn(low) 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.

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.

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Zhenya Wang

Full Text Available 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, Zn(high; 50 ppm, Zn(low. 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 Zn(high and E. faecium groups gained weight after infection while those in the control group (Zn(low 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 Zn(high+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 Zn(high and E. faecium groups at single time points after infection compared to the Zn(low 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.

Associations between the use of antimicrobial agents for growth promotion and the occurrence of resistance among Enterococcus faecium from broilers and pigs in Denmark, Finland, and Norway

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Kruse, H.; Tast, E.

2000-01-01

This study compares the susceptibility of Enterococcus faecium isolated from pigs and poultry in Denmark, Finland, and Norway to antimicrobial agents used for growth promotion. E. faecium was isolated from 211 broilers and 55 pigs in Denmark in 1997, from Norwegian 55 poultry farms (turkey and br......%) of the virginiamycin-resistant isolates from pigs in Denmark. This study indicates that the use of antimicrobial agents for growth promotion in Denmark, Finland, and Norway have selected for resistance to most of these drugs among E. faecium in food animals....... as resistant to monensin or salinomycin. In general, an association between the usage of antimicrobial agents in the respective countries and the occurrence of associated resistance was observed. Resistance to avilamycin was frequently observed among isolates from broilers in Denmark, where avilamycin has been...... used, whereas all isolates from Finland and Norway, where these drugs have not been used, were susceptible. The same phenomenon could be observed for avoparcin, bacitracin, tylosin, and virginiamycin; resistance was frequently observed among isolates from where these antimicrobials have been widely...

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

DEFF Research Database (Denmark)

Wegener, Henrik Caspar; Aarestrup, Frank Møller; Jensen, Lars Bogø

1999-01-01

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......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...

Molecular Occurrence of Enterocin A Gene among Enterococcus faecium Strains Isolated from Gastro-Intestinal Tract and Antimicrobial Effect of this Bacteriocin Against Clinical Pathogens

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Mitra Salehi

2014-06-01

Materials and Methods: In this study occurrence of class II enterocin structural gene (enterocin A in a target of 42 Enterococcus faecium strains, isolated from gastrointestinal tract of animal have been surveyed. E. faecium identification and occurrence of enterocin A gene was performed by PCR method. Cell-free neutralized supernatant of gene positive strains was used to test bacteriocin production and antimicrobial spectrum of supernatant was assayed by wall diffusion method on the gram-positive and negative indicators bacteriaResults: Based on our results, 73.8% of isolated strains had enterocin A gene that they inhibited growth of indicator bacteria such as clinical strain of Pseudomonas aeruginosa, Salmonella enteric PTCC1709, Listeria monocytogenes, Bacillus cereus and Bacillus subtilis.Conclusions: Studied enterocins have growth inhibitory spectrum on Gram-positive and Gram-negative bacteria especially against pathogenic bacteria in the gastrointestinal tract. Therefore, these strains have the potential to explore and use as, alternative antimicrobial compound and bio-preservatives in food or feed or as probiotics.

Solution Structure of Enterocin HF, an Antilisterial Bacteriocin Produced by Enterococcus faecium M3K31.

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Arbulu, Sara; Lohans, Christopher T; van Belkum, Marco J; Cintas, Luis M; Herranz, Carmen; Vederas, John C; Hernández, Pablo E

2015-12-16

The solution structure of enterocin HF (EntHF), a class IIa bacteriocin of 43 amino acids produced by Enterococcus faecium M3K31, was evaluated by CD and NMR spectroscopy. Purified EntHF was unstructured in water, but CD analysis supports that EntHF adopts an α-helical conformation when exposed to increasing concentrations of trifluoroethanol. Furthermore, NMR spectroscopy indicates that this bacteriocin adopts an antiparallel β-sheet structure in the N-terminal region (residues 1-17), followed by a well-defined central α-helix (residues 19-30) and a more disordered C-terminal end (residues 31-43). EntHF could be structurally organized into three flexible regions that might act in a coordinated manner. This is in agreement with the absence of long-range nuclear Overhauser effect signals between the β-sheet domain and the C-terminal end of the bacteriocin. The 3D structure recorded for EntHF fits emerging facts regarding target recognition and mode of action of class IIa bacteriocins.

Partial purification and characterization of a bacteriocin produced by Enterococcus faecium 130 isolated from mozzarella cheese

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Fabrício Luiz Tulini

2011-03-01

Full Text Available Lactic acid bacteria are important in foods as potential probiotics and also due to the ability to produce antimicrobial compounds that can contribute for biopreservation. In this work, the bacteriocin produced by the food isolate Enterococcus faecium 130 was partially purified and characterized. The compound was active against Gram-positive bacteria, including Listeria monocytogenes. It was produced after 4 days of storage at a broad temperature range (4 to 37 °C; it was stable at pH ranging from 2 to 10 with no loss of activity after heating at 100 °C for 15 minutes. Bacteriocin was partially purified by the adsorption-desorption technique, and the analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE showed a molecular mass of 3.5 to 6.5 kDa. These data encourage studies on application of this bacteriocin in food systems as an additional hurdle to microbial growth.

Infecção ou colonização por micro-organismos resistentes: identificação de preditores Infection or colonization with resistant microorganisms: identification of predictors

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Graciana Maria de Moraes

2013-01-01

Full Text Available OBJETIVO: Identificar os fatores preditores de infecção ou colonização por micro-organismos resistentes. MÉTODOS: Foi realizado estudo quantitativo de coorte prospectivo. Foram realizadas a análise descritiva, para conhecimento da população do estudo, e a análise discriminante, para identificação dos fatores preditores. RESULTADOS: Foram incluídos 85 pacientes com infecções por micro-organismos resistentes: Pseudomonas aeruginosas resistente aos carbapenêmicos (24,7%, Acinetobacter resistente aos carbapenêmicos (21,2%, Staphylococcus aureus resistente à meticilina (25,9%, Enterococcus spp. resistente à vancomicina (17,6% e Klebsiella pneumoniae resistente aos carbapenêmicos (10,6%. A análise discriminante identificou transferências de outros hospitais e internação na Unidade de Terapia Intensiva como fatores preditores para ocorrência de infecção pelos grupos S. aureus resistente à meticilina, Acinetobacter resistente aos carbapenêmicos e K. pneumoniae resistente aos carbapenêmicos. Nenhuma das variáveis estudadas foi discriminante para Enterococcus spp. resistente à vancomicina e P. aeruginosas resistente aos carbapenêmico. CONCLUSÃO: Os fatores preditores encontrados foram: internação na UTI e a transferências de outros hospitais.OBJECTIVE: Identifying predictors of infection or colonization with resistant microorganisms. METHODS: A quantitative study of prospective cohort was carried out. A descriptive analysis was performed in order to know the population of the study and a discriminant analysis was performed to identify the predictors. RESULTS: In this study were included 85 patients with infections caused by resistant microorganisms: carbapenem-resistant Pseudomonas aeruginosas (24.7%; carbapenem-resistant Acinetobacter (21.2%; methicillin-resistant Staphylococcus aureus (25.9%, vancomycin-resistant Enterococcus spp (17.6% and carbapenem-resistant Klebsiella pneumonia (10.6%. The discriminant analysis

Evaluación in vitro de las cepas de Enterococcus faecalis y Enterococcus faecium, como potenciales probióticos

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Diana Alejandra Pico Veslin

2016-06-01

Full Text Available Introducción: Los probióticos son conocidos como microrganismos vivos, que favorecen el equilibrio microbiano en el tracto gastrointestinal, sus metabolitos (ácidos orgánicos, ácido láctico, entre otros inhiben el crecimiento de patógenos, a nivel de sistema inmune activan la respuesta humoral (IL 2 y activan la fagocitosis. Diferentes estudios han demostrado que la utilización de probióticos en el sector avícola como suplemento, relegaría el uso de antibióticos, puesto que la utilización de los mismos, ha generado casos de resistencia bacteriana, afectando al consumidor final y  convirtiéndose en un problema de salud pública. El uso de probióticos según la FAO, encaminaría en estrategias de mejoramiento global del rendimiento y bienestar animal en  países en desarrollo. Objetivo: Identificar fenotípicamente el comportamiento de las cepas Enterorococcus faecium, Enterococcus faecalis aisladas del intestino de pollo de engorde y gallina comercial (Gallus gallus frente a  antibacterianos. Metodología: estudio descriptivo de corte transversal. Se tomaron muestras del mucus intestinal de las aves (íleon, yeyuno y duodeno  aisladas en medio MRS el cual permite evidenciar el crecimiento de bacterias ácido lácticas, se  realizaron pruebas microbiológicas y bioquímicas utilizando el sistema  semiautomatizado Crystal para Gram positivos  (BBLTM CrystalTM Gram-PositiveID Kit  posteriormente estas cepas fueron evaluadas en algunas características como potenciales probióticos: resistencia a pH bajo, concentraciones biliares de 0.1% a 0.3%, producción de hemolisinas, prueba de antagonismo;  posteriormente se evaluó un factor de virulencia,  la presencia de genes de resistencia a ciertos antibióticos; se realizó la caracterización fenotípica mediante difusión en disco Kirby Bauer , para evaluar la resistencia y/o sensibilidad, se  seleccionaron  los  antibióticos de las  familias Glicopetidos (Vancomicina, Inh

Characterization and susceptibility patterns of clinically important Enterococcus species in eastern Nepal.

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Acharya, A; Khanal, A; Kanungo, R; Mohapatra, T

2007-12-01

Life threatening infections caused by enterococcus species with multidrug resistance has emerged as a threat to medical care in the present era. This study was conducted to characterize enterococcus species isolated from different clinical samples and to detect the pattern of susceptibility to some of the commonly used antibiotics in B.P Koirala Institute of Health Sciences (BPKIHS), a tertiary care hospital in eastern Nepal. Clinical samples submitted to the microbiology unit of Central Laboratory Service (CLS) for culture and sensitivity during March 2002 - February 2003 was analyzed. Enterococcus species were identified by colony characteristics, gram staining and relevant biochemical tests. Antibiotic susceptibility test was done by the Kirby Bauer disc diffusion technique. Of 50 Enterococcus species isolated, E. faecalis was the predominant isolate (48.0%) followed by E. faecium (32.0%) and E. avium (20.0%). Eighty-eight percent of E. faecalis showed sensitivity to cephotaxime and 87.0% to vancomycin. Multiple drug resistance was observed most commonly in E. faecium. Seventeen percent of E. faecium were resistant to vancomycin and 63.0% to ciprofloxacin and 44.0% to ampicillin. On the contrary E. avium rarely showed resistance to the antimicrobials tested including vancomycin. Enterococcal infections are common nowadays specially in hospitalized patients. Inappropriate use of antibiotics in clinical practice and poultry should be discouraged to prevent the emergence of multidrug resistant species.

Engineering the l-Arabinose Isomerase from Enterococcus Faecium for d-Tagatose Synthesis

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Marylane de Sousa

2017-12-01

Full Text Available l-Arabinose isomerase (EC 5.3.1.4 (l-AI from Enterococcus faecium DBFIQ E36 was overproduced in Escherichia coli by designing a codon-optimized synthetic araA gene. Using this optimized gene, two N- and C-terminal His-tagged-l-AI proteins were produced. The cloning of the two chimeric genes into regulated expression vectors resulted in the production of high amounts of recombinant N-His-l-AI and C-His-l-AI in soluble and active forms. Both His-tagged enzymes were purified in a single step through metal-affinity chromatography and showed different kinetic and structural characteristics. Analytical ultracentrifugation revealed that C-His-l-AI was preferentially hexameric in solution, whereas N-His-l-AI was mainly monomeric. The specific activity of the N-His-l-AI at acidic pH was higher than that of C-His-l-AI and showed a maximum bioconversion yield of 26% at 50 °C for d-tagatose biosynthesis, with Km and Vmax parameters of 252 mM and 0.092 U mg−1, respectively. However, C-His-l-AI was more active and stable at alkaline pH than N-His-l-AI. N-His-l-AI follows a Michaelis-Menten kinetic, whereas C-His-l-AI fitted to a sigmoidal saturation curve.

Analysis of the world epidemiological situation among vancomycin-resistant Enterococcus faecium infections and the current situation in Poland

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Talaga-Ćwiertnia, Katarzyna; Bulanda, Małgorzata

2018-01-01

Vancomycin-resistant Enterococcus faecium (VREfm) strains have become an important hospital pathogen due to their rapid spread, high mortality rate associated with infections and limited therapeutic options. Vancomycin resistance is predominantly mediated by VanA or VanB phenotypes, which differ as regards maintaining sensitivity to teicoplanin in the VanB phenotype. The majority of VREfm cases in the United States, Europe, Korea, South America and Africa are currently caused by the VanA phenotype. However, the epidemics in Australia and Singapore are chiefly brought about by the VanB phenotype. The rate of VREfm isolate spread varies greatly. The greatest percentage of VREfm is now recorded in the USA, Ireland and Australia. Supervision of VRE is implemented to varying degrees. Therefore, the epidemiological situation in some countries is difficult to assess due to limited data or lack thereof.

Effect of calcium and magnesium on the antimicrobial action of enterocin LR/6 produced by Enterococcus faecium LR/6.

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Kumar, Manoj; Srivastava, Sheela

2011-06-01

Enterococci are well-known producers of antimicrobial peptides (enterocins) that possess potential as biopreservatives in food. In this study, divalent cations and release of intracellular potassium were used to assess the mechanism of interaction and killing of enterocin LR/6 produced by Enterococcus faecium LR/6 on three target Gram-positive and Gram-negative bacteria, namely Micrococcus luteus, Enterococcus sp. strain LR/3 and Escherichia coli K-12. Whilst treatment with enterocin LR/6 in all cases led to a significant loss of viability, suggesting a bactericidal mode of action, E. coli K-12 showed better tolerance than the other two strains. Bacteriocins have generally been reported to create pores in the membrane of sensitive cells and this function is diminished by divalent cations. In this study it was shown that Ca(2+) and Mg(2+) markedly improved the viability of enterocin LR/6-treated cells in a concentration-dependent manner. K(+) release as a sign of membrane leakiness was higher in M. luteus compared with the other two test strains. In agreement with the viability response, pre-exposure to Ca(2+) and Mg(2+) substantially reduced the amount of K(+) leakage by M. luteus and Enterococcus sp.; in the case of E. coli K-12, no leakage of K(+) was recorded. These results suggest that enterocin LR/6, which possesses good antibacterial potential, may not be very effective as a preservative in foods containing high concentrations of calcium and magnesium. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

The fosfomycin resistance gene fosB3 is located on a transferable, extrachromosomal circular intermediate in clinical Enterococcus faecium isolates.

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Xiaogang Xu

Full Text Available Some VanM-type vancomycin-resistant Enterococcus faecium isolates from China are also resistant to fosfomycin. To investigate the mechanism of fosfomycin resistance in these clinical isolates, antimicrobial susceptibility testing, filter-mating, Illumina/Solexa sequencing, inverse PCR and fosfomycin resistance gene cloning were performed. Three E. faecium clinical isolates were highly resistant to fosfomycin and vancomycin with minimal inhibitory concentrations (MICs >1024 µg/ml and >256 µg/ml, respectively. The fosfomycin and vancomycin resistance of these strains could be co-transferred by conjugation. They carried a fosfomycin resistance gene fosB encoding a protein differing by one or two amino acids from FosB, which is encoded on staphylococcal plasmids. Accordingly, the gene was designated fosB3. The fosB3 gene was cloned into pMD19-T, and transformed into E. coli DH5α. The fosfomycin MIC for transformants with fosB3 was 750-fold higher than transformants without fosB3. The fosB3 gene could be transferred by an extrachromosomal circular intermediate. The results indicate that the fosB3 gene is transferable, can mediate high level fosfomycin resistance in both Gram-positive and Gram-negative bacteria, and can be located on a circular intermediate.

Identification, Characterization, and Three-Dimensional Structure of the Novel Circular Bacteriocin, Enterocin NKR-5-3B, from Enterococcus faecium.

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Himeno, Kohei; Rosengren, K Johan; Inoue, Tomoko; Perez, Rodney H; Colgrave, Michelle L; Lee, Han Siean; Chan, Lai Y; Henriques, Sónia Troeira; Fujita, Koji; Ishibashi, Naoki; Zendo, Takeshi; Wilaipun, Pongtep; Nakayama, Jiro; Leelawatcharamas, Vichien; Jikuya, Hiroyuki; Craik, David J; Sonomoto, Kenji

2015-08-11

Enterocin NKR-5-3B, one of the multiple bacteriocins produced by Enterococcus faecium NKR-5-3, is a 64-amino acid novel circular bacteriocin that displays broad-spectrum antimicrobial activity. Here we report the identification, characterization, and three-dimensional nuclear magnetic resonance solution structure determination of enterocin NKR-5-3B. Enterocin NKR-5-3B is characterized by four helical segments that enclose a compact hydrophobic core, which together with its circular backbone impart high stability and structural integrity. We also report the corresponding structural gene, enkB, that encodes an 87-amino acid precursor peptide that undergoes a yet to be described enzymatic processing that involves adjacent cleavage and ligation of Leu(24) and Trp(87) to yield the mature (circular) enterocin NKR-5-3B.

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.

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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.

Molecular Analysis of VanA Outbreak of Enterococcus faecium in Two Warsaw Hospitals: The Importance of Mobile Genetic Elements

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Ewa Wardal

2014-01-01

Full Text Available Vancomycin-resistant Enterococcus faecium represents a growing threat in hospital-acquired infections. Two outbreaks of this pathogen from neighboring Warsaw hospitals have been analyzed in this study. Pulsed-field gel electrophoresis (PFGE of SmaI-digested DNA, multilocus VNTR analysis (MLVA, and multilocus sequence typing (MLST revealed a clonal variability of isolates which belonged to three main lineages (17, 18, and 78 of nosocomial E. faecium. All isolates were multidrug resistant and carried several resistance, virulence, and plasmid-specific genes. Almost all isolates shared the same variant of Tn1546 transposon, characterized by the presence of insertion sequence ISEf1 and a point mutation in the vanA gene. In the majority of cases, this transposon was located on 50 kb or 100 kb pRUM-related plasmids, which lacked, however, the axe-txe toxin-antitoxin genes. 100 kb plasmid was easily transferred by conjugation and was found in various clonal backgrounds in both institutions, while 50 kb plasmid was not transferable and occurred solely in MT159/ST78 strains that disseminated clonally in one institution. Although molecular data indicated the spread of VRE between two institutions or a potential common source of this alert pathogen, epidemiological investigations did not reveal the possible route by which outbreak strains disseminated.

Molecular Analysis of VanA Outbreak of Enterococcus faecium in Two Warsaw Hospitals: The Importance of Mobile Genetic Elements

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Wardal, Ewa; Markowska, Katarzyna; Żabicka, Dorota; Wróblewska, Marta; Giemza, Małgorzata; Mik, Ewa; Połowniak-Pracka, Hanna; Woźniak, Agnieszka; Hryniewicz, Waleria; Sadowy, Ewa

2014-01-01

Vancomycin-resistant Enterococcus faecium represents a growing threat in hospital-acquired infections. Two outbreaks of this pathogen from neighboring Warsaw hospitals have been analyzed in this study. Pulsed-field gel electrophoresis (PFGE) of SmaI-digested DNA, multilocus VNTR analysis (MLVA), and multilocus sequence typing (MLST) revealed a clonal variability of isolates which belonged to three main lineages (17, 18, and 78) of nosocomial E. faecium. All isolates were multidrug resistant and carried several resistance, virulence, and plasmid-specific genes. Almost all isolates shared the same variant of Tn1546 transposon, characterized by the presence of insertion sequence ISEf1 and a point mutation in the vanA gene. In the majority of cases, this transposon was located on 50 kb or 100 kb pRUM-related plasmids, which lacked, however, the axe-txe toxin-antitoxin genes. 100 kb plasmid was easily transferred by conjugation and was found in various clonal backgrounds in both institutions, while 50 kb plasmid was not transferable and occurred solely in MT159/ST78 strains that disseminated clonally in one institution. Although molecular data indicated the spread of VRE between two institutions or a potential common source of this alert pathogen, epidemiological investigations did not reveal the possible route by which outbreak strains disseminated. PMID:25003118

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.

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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

Relentless spread and adaptation of non-typeable vanA vancomycin-resistant Enterococcus faecium: a genome-wide investigation.

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van Hal, Sebastiaan J; Beukers, Alicia G; Timms, Verlaine J; Ellem, Justin A; Taylor, Peter; Maley, Michael W; Newton, Peter J; Ferguson, John K; Lee, Andie; Chen, Sharon C-A; Sintchenko, Vitali

2018-03-16

VRE are prevalent among patients in ICUs. Non-typeable vanA VRE, due to loss of one of the genes used for MLST (pstS), have increased in Australia, suggestive of a new, hospital-acquired lineage. To understand the significance of this lineage and its transmission using WGS of strains isolated from patients in ICUs across New South Wales, Australia. A total of 240 Enterococcus faecium isolates collected between February and May 2016, and identified by conventional PCR as vanA positive, were sequenced. Isolates originated from 12 ICUs in New South Wales, grouped according to six local health districts, and represented both rectal screening swab (n = 229) and clinical (n = 11) isolates. ST analysis revealed the absence of the pstS gene in 84.2% (202 of 240) of vanA isolates. Two different non-typeable STs were present based on different allelic backbone patterns. Loss of the pstS gene appeared to be the result of multiple recombination events across this region. Evidence for pstS-negative lineage spread across all six local health districts was observed suggestive of inter-hospital transmission. In addition, multiple outbreaks were detected, some of which were protracted and lasted for the duration of the study. These findings confirmed the evolution, emergence and dissemination of non-typeable vanA E. faecium. This study has highlighted the utility of WGS when attempting to describe accurately the hospital-based pathogen epidemiology, which in turn will continue to inform optimal infection control measures necessary to halt the spread of this important nosocomial organism.

Growth of Enterococcus durans E204 producing bacteriocin-like ...

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El Ouardy

2012-01-10

Jan 10, 2012 ... inhibition of Enterococcus faecium 410 CECT in 6 h of incubation. The highest ... as natural food additives for the elimination of spoilage and pathogeinic ..... autohydrolysed fish viscera for nisin and pediocin production. J.

Isolation and characterization of a new bacteriocin, termed enterocin M, produced by environmental isolate Enterococcus faecium AL41.

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Mareková, Mária; Lauková, Andrea; Skaugen, Morten; Nes, Ingolf

2007-08-01

The new bacteriocin, termed enterocin M, produced by Enterococcus faecium AL 41 showed a wide spectrum of inhibitory activity against the indicator organisms from different sources. It was purified by (NH4)2SO4 precipitation, cation-exchange chromatography and reverse phase chromatography (FPLC). The purified peptide was sequenced by N-terminal amino acid Edman degradation and a mass spectrometry analysis was performed. By combining the data obtained from amino acid sequence (39 N-terminal amino acid residues was determined) and the molecular weight (determined to be 4628 Da) it was concluded that the purified enterocin M is a new bacteriocin, which is very similar to enterocin P. However, its molecular weight is different from enterocin P (4701.25). Of the first 39 N-terminal residues of enterocin M, valine was found in position 20 and a lysine in position 35, while enterocin P has tryptophane residues in these positions.

Genetic identification of the bacteriocins produced by Enterococcus faecium IT62 and evidence that bacteriocin 32 is identical to enterocin IT.

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Izquierdo, Esther; Cai, Yimin; Marchioni, Eric; Ennahar, Saïd

2009-05-01

Enterococcus faecium IT62, a strain isolated from ryegrass in Japan, produces three bacteriocins (enterocins L50A, L50B, and IT) that have been previously purified and the primary structures of which have been determined by amino acid sequencing (E. Izquierdo, A. Bednarczyk, C. Schaeffer, Y. Cai, E. Marchioni, A. Van Dorsselaer, and S. Ennahar, Antimicrob. Agents Chemother., 52:1917-1923, 2008). Genetic analysis showed that the bacteriocins of E. faecium IT62 are plasmid encoded, but with the structural genes specifying enterocin L50A and enterocin L50B being carried by a plasmid (pTAB1) that is separate from the one (pTIT1) carrying the structural gene of enterocin IT. Sequencing analysis of a 1,475-bp region from pTAB1 identified two consecutive open reading frames corresponding, with the exception of 2 bp, to the genes entL50A and entL50B, encoding EntL50A and EntL50B, respectively. Both bacteriocins are synthesized without N-terminal leader sequences. Genetic analysis of a sequenced 1,380-bp pTIT1 fragment showed that the genes entIT and entIM, encoding enterocin IT and its immunity protein, respectively, were both found in E. faecium VRE200 for bacteriocin 32. Enterocin IT, a 6,390-Da peptide made up of 54 amino acids, has been previously shown to be identical to the C-terminal part of bacteriocin 32, a 7,998-Da bacteriocin produced by E. faecium VRE200 whose structure was deduced from its structural gene (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). By combining the biochemical and genetic data on enterocin IT, it was concluded that bacteriocin 32 is in fact identical to enterocin IT, both being encoded by the same plasmid-borne gene, and that the N-terminal leader peptide for this bacteriocin is 35 amino acids long and not 19 amino acids long as previously reported.

PCR-based plasmid typing in Enterococcus faecium strains reveals widely distributed pRE25-, pRUM-, pIP501-and pHT beta-related replicons associated with glycopeptide resistance and stabilizing toxin-antitoxin systems

DEFF Research Database (Denmark)

Rosvoll, T.C.S.; Pedersen, T.; Sletvold, H.

2010-01-01

A PCR-based typing scheme was applied to identify plasmids in an epidemiologically and geographically diverse strain collection of Enterococcus faecium (n=93). Replicon types of pRE25 (n=56), pRUM (n=41), pIP501 (n=17) and pHT beta (n=14) were observed in 83% of the strains, while pS86, pCF10, pA...

Isolation of vancomycin-resistant Enterococcus from apparently healthy human animal attendants, cattle and cattle wastes in Tanzania

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Madoshi, B. P.; Mtambo, M. M.A.; Muhairwa, A. P.

2018-01-01

faecalis was the most prevalent species from all sources of isolation (43·5%), followed by Enterococcus faecium (38·4%). Isolates of E. faecium showed a higher number of phenotypic antimicrobial resistance than isolates of E. faecalis. Fifty-eight isolates, which showed resistance or intermediate...

Efficacy of Daptomycin Monotherapy and In Combination with β-lactams for Daptomycin-Susceptible Enterococcus faecium Harboring LiaSR Substitutions: Influence of The Inoculum Effect.

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Kebriaei, Razieh; Rice, Seth A; Singh, Kavindra V; Stamper, Kyle C; Dinh, An Q; Rios, Rafael; Diaz, Lorena; Murray, Barbara E; Munita, Jose M; Tran, Truc T; Arias, Cesar A; Rybak, Michael J

2018-05-14

Enterococcus faecium that harbor LiaFSR substitutions but are phenotypically susceptible to daptomycin (DAP) by current breakpoints are problematic since predisposition to resistance may lead to therapeutic failure. Using a simulated endocardial vegetation (SEV) PK/PD model, we investigated DAP regimens (6, 8 and 10 mg/kg/day) as monotherapy and in combination with ampicillin (AMP), ceftaroline (CPT) or ertapenem (ERT) against E. faecium HOU503, a DAP-susceptible strain that harbors common LiaS and LiaR substitutions found in clinical isolates (T120S and W73C, respectively). Of interest, the efficacy of DAP monotherapy, at any dose regimen, was dependent on the size of the inoculum. At an inoculum of ∼10 9 CFU/g, DAP doses of 6-8 mg/kg/d were not effective and led to significant regrowth with emergence of resistant derivatives. In contrast, at an inoculum of ∼10 7 , marked reductions in bacterial counts were observed with DAP 6 mg/kg/d with no resistance. The inoculum effect was confirmed in a rat model using humanized DAP exposures. Combinations of DAP with AMP, CPT or ERT demonstrated enhanced eradication and reduced potential for resistance allowing for de-escalation of the DAP dose. Persistence of the LiaRS substitutions were identified in DAP-resistant isolates recovered from the SEV model and in DAP-resistant derivatives of an initially DAP-susceptible clinical isolate of E. faecium (HOU668) harboring LiaSR substitutions and recovered from a patient with a recurrent bloodstream infection. Our results provide novel data for the use of DAP monotherapy and combinations for recalcitrant E. faecium infections and paves the way for testing these approaches in humans. Copyright © 2018 American Society for Microbiology.

Control of Listeria monocytogenes in goat's milk and goat's jben by the bacteriocinogenic Enterococcus faecium F58 strain.

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Achemchem, Fouad; Abrini, Jamal; Martínez-Bueno, Manuel; Valdivia, Eva; Maqueda, Mercedes

2006-10-01

The bacteriocinogenic Enterococcus faecium F58 strain, a natural goat's jben cheese isolate, lacks decarboxylase activity involved in most biogenic amine formation. It was also sensitive to 13 antibiotics assayed and free of virulence and vancomycin resistance genes. The F58 strain reached the stationary phase after 12 h of growth in sterile goat's milk, and the production of enterocin F-58 (Ent L50) was first detected after 48 h (400 AU/ml), thereafter remaining stable up to 5 days. The effectiveness of the F58 strain in controlling Listeria monocytogenes serovar 4b in reduced fat and whole goat's milk, and in goat's jben has been examined. Coculture experiments of F58-L. monocytogenes in both types of milk demonstrated that listeriae were not eliminated, although reductions by 1 to 4 log units were found. Nevertheless, when the F58 strain was previously inoculated in whole milk and left to grow for 12 h before contamination, the pathogen was completely eliminated after 130 h of coculture. Production of jben cheese contaminated with L. monocytogenes prior to packaging, using preparations of F58-producer strain, caused a significant decrease in the number of viable listeriae, which were undetectable after 1 week of cheese storage at 22 degrees C. Altogether, results from this study suggest that E. faecium F58 strain may be used as an adjunct culture in cheese to control contamination and growth of L. monocytogenes by in situ enterocin production, thus providing an additional hurdle to enhance control of this pathogen.

Fermented sausage production using E. faecium as starter culture: Physicochemical and microbiological profile, sensorial acceptance and cellular viability

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Catharina Calochi Pires de Carvalho

2017-09-01

Full Text Available Fermented sausages are defined as a mixture of lean meat and fat, curing salts, sucrose and spices, stuffed in a natural or artificial casing and submitted to fermentation and air-drying process. Starter culture and ripening process may affect the quality and acceptability of the final product. Current research evaluates the use of Enterococcus faecium as starter culture in fermented sausage production and its physicochemical and microbiological profile during maturation process, coupled to sausage sensory acceptance after ripening. Enterococcus faecium showed 10.9 log CFU g-1 and remained viable after the ripening period with 8.32 log CFU g-1. Fermented sausage was monitored during the ripening period by physicochemical (pH control, water activity and weight loss and microbiological (analysis of coagulase-positive Staphylococcus, coliforms and Salmonella spp. analyses. All tests complied with standards established by Brazilian legislation and did not interfere in final product quality. Results showed that E. faecium was resistant to curing salt and sodium chloride, maintaining its viability during ripening and conferring beneficial effects on fermented sausage technological characteristics. E. faecium also proved to be in vitro resistant to simulate passage through the human digestive tract. Fermented sausage containing E. faecium had better sensory acceptance than commercial sausage evaluated.

Enterococcus infection biology: lessons from invertebrate host models.

Science.gov (United States)

Yuen, Grace J; Ausubel, Frederick M

2014-03-01

The enterococci are commensals of the gastrointestinal tract of many metazoans, from insects to humans. While they normally do not cause disease in the intestine, they can become pathogenic when they infect sites outside of the gut. Recently, the enterococci have become important nosocomial pathogens, with the majority of human enterococcal infections caused by two species, Enterococcus faecalis and Enterococcus faecium. Studies using invertebrate infection models have revealed insights into the biology of enterococcal infections, as well as general principles underlying host innate immune defense. This review highlights recent findings on Enterococcus infection biology from two invertebrate infection models, the greater wax moth Galleria mellonella and the free-living bacteriovorous nematode Caenorhabditis elegans.

Physical, biochemical and genetic characterization of enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from Thai indigenous chicken intestinal tract

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Kraiyot Saelim

2015-06-01

Full Text Available Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decreased the population of Ent. faecalis VanB from 6.03 to 4.03 log CFU/ml. The lethal mode of action of enterocin CE5-1 appeared to be pore and filament formation in the cell wall. PCR sequencing analysis revealed the presence of two open reading frames (ORFs, containing enterocin CE5-1 (entCE5-1 and enterocin immunity (entI gene. Therefore, enterocin CE5-1 from Ent. faecium CE5-1 could possibly be used as an antimicrobial agent to control foodborne pathogen, spoilage bacteria and antibiotic-resistant enterococci in foods, feeds and the environments.

Comparison of antimicrobial resistance phenotypes and resistance genes in Enterococcus faecalis and Enterococcus faecium from humans in the community, broilers and pigs in Denmark

DEFF Research Database (Denmark)

Aarestrup, Frank Møller; Agersø, Yvonne; Gerner-Smidt, P.

2000-01-01

. faecium isolates of human and animal origin, examined. tet(K) was not observed, whereas tet(L) was detected in 17% of tetracycline resistant E. faecalis isolates and in 16% of the E. faecium isolates. tet(O) was not detected in any of the isolates from pigs, but was observed in 38% of E. faecalis isolates...... from broilers, in two E. faecalis isolates from humans and in three E. faecium isolates from broilers. tet(S) was not detected among isolates from animals, but was observed in 31% of E. faecalis and one E. faecium isolate from humans. This study showed a frequent occurrence of antimicrobial resistance...

Phenotypic and genotypic characterization of vancomycin-resistant Enterococcus faecium clinical isolates from two hospitals in Mexico: First detection of VanB phenotype-vanA genotype.

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Bocanegra-Ibarias, Paola; Flores-Treviño, Samantha; Camacho-Ortiz, Adrián; Morfin-Otero, Rayo; Villarreal-Treviño, Licet; Llaca-Díaz, Jorge; Martínez-Landeros, Erik Alan; Rodríguez-Noriega, Eduardo; Calzada-Güereca, Andrés; Maldonado-Garza, Héctor Jesús; Garza-González, Elvira

2016-01-01

Enterococcus faecium has emerged as a multidrug-resistant nosocomial pathogen involved in outbreaks worldwide. Our aim was to determine the antimicrobial susceptibility, biofilm production, and clonal relatedness of vancomycin-resistant E. faecium (VREF) clinical isolates from two hospitals in Mexico. Consecutive clinical isolates (n=56) were collected in two tertiary care hospitals in Mexico from 2011 to 2014. VREF isolates were characterized by phenotypic and molecular methods including pulsed-field gel electrophoresis (PFGE). VREF isolates were highly resistant to vancomycin, erythromycin, norfloxacin, high-level streptomycin, and teicoplanin, and showed lower resistance to tetracycline, nitrofurantoin and quinupristin-dalfopristin. None of the isolates were resistant to linezolid. The vanA gene was detected in all isolates. Two VanB phenotype-vanA genotype isolates, highly resistant to vancomycin and susceptible to teicoplanin, were detected. Furthermore, 17.9% of the isolates were classified as biofilm producers, and the espfm gene was found in 98.2% of the isolates. A total of 37 distinct PFGE patterns and 6 clones (25% of the isolates as clone A, 5.4% as clone B, and 3.6% each as clone C, D, E, and F) were detected. Clone A was detected in 5 different wards of the same hospital during 14 months of surveillance. The high resistance to most antimicrobial agents and the moderate cross-transmission of VREF detected accentuates the need for continuous surveillance of E. faecium in the hospital setting. This is also the first reported incidence of the E. faecium VanB phenotype-vanA genotype in the Americas. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

THE PROBIOTIC Enterococcus faecium MODIFIES THE INTESTINAL MORPHOMETRIC PARAMETERS IN WEANING PIGLETS

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Johana Andrea Ciro Galeano

2016-01-01

Full Text Available Global trends for animal production have seen a decrease in the use of antimicrobial compounds in feed, generating the need to implement new nutritional strategies that stimulate growth and promote intestinal health. This study aimed to determine whether the addition of E. faecium in drinking water improves intestinal morphometric parameters in post- weaning pigs compared with the probiotics strains L. acidophilus and L. casei on days 1 (21 days of age, 15 and 30 postweaning. The small intestine was completely removed to evaluate the morphometric parameters (length and width of villi and crypts in the different intestinal segments (duodenum, jejunum, and ileum. They were fed for 30 days with two diets: commercial diet with or without antibiotics. The different probiotics, L. acidophillus, L. casei and E. faecium, were administered in the drinking water of the animals that consumed the commercial diet without antibiotics. A randomized block design in split-plot arrangement was used. There was a significant increase (P<0.01 in the width and length of villi, and a decrease (P<0.01 in the values obtained for the width and depth of crypts in the animals that consumed E .faecium, as compared to those that consumed the diet with addition of antibiotics. The use of probiotics, especially E. faecium, is a nutritional treatment strategy when antimicrobial compound are used, improving the intestinal morphometric parameters and, at the same time, the digestive and productive parameters of the animals. Work is in progress to investigate the effects of probiotic supplementation on the mofication of gut microbiota of post-weaning piglets

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

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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.

Prevalence and Antimicrobial Resistance of Enterococcus Species: A Hospital-Based Study in China

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Wei Jia

2014-03-01

Full Text Available Objective: to investigate the prevalence and antimicrobial resistance of Enterococcus species isolated from a university hospital, and explore the mechanisms underlying the antimicrobial resistance, so as to provide clinical evidence for the inappropriate clinical use of antimicrobial agents and the control and prevention of enterococcal infections. Methods: a total of 1,157 enterococcal strains isolated from various clinical specimens from January 2010 to December 2012 in the General Hospital of Ningxia Medical University were identified to species level with a VITEK-2 COMPACT fully automated microbiological system, and the antimicrobial susceptibility of Enterococcus species was determined using the Kirby-Bauer disc diffusion method. The multiple-drug resistant enterococcal isolates were screened from the clinical isolates of Enterococcus species from the burns department. The minimal inhibitory concentration (MIC of Enterococcus species to the three fluoroquinolones, including ciprofloxacin, gatifloxacin and levofloxacin was determined with the agar dilution method, and the changes in the MIC of Enterococcus species to the three fluoroquinolones following reserpine treatment were evaluated. The β-lactam, aminoglycoside, tetracycline, macrolide, glycopeptide resistance genes and the efflux pump emeA genes were detected in the enterococcal isolates using a polymerase chain reaction (PCR assay. Results: the 1,157 clinical isolates of Enterococcus species included 679 E. faecium isolates (58.7%, 382 E. faecalis isolates (33%, 26 E. casseliflavus isolates (2.2%, 24 E. avium isolates (2.1%, and 46 isolates of other Enterococcus species (4%. The prevalence of antimicrobial resistance varied significantly between E. faecium and E. faecalis, and ≤1.1% of these two Enterococcus species were found to be resistant to vancomycin, teicoplanin or linezolid. In addition, the Enterococcus species isolated from different departments of the hospital

Modulation of virulence and antibiotic susceptibility of enteropathogenic Escherichia coli strains by Enterococcus faecium probiotic strain culture fractions.

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Ditu, Lia-Mara; Chifiriuc, Mariana Carmen; Bezirtzoglou, Eugenia; Voltsi, Chrysa; Bleotu, Coralia; Pelinescu, Diana; Mihaescu, Grigore; Lazar, Veronica

2011-12-01

The increasing rate of antimicrobial resistance drastically reduced the efficiency of conventional antibiotics and led to the reconsideration of the interspecies interactions in influencing bacterial virulence and response to therapy. The aim of the study was the investigation of the influence of the soluble and cellular fractions of Enterococcus (E.) faecium CMGB16 probiotic culture on the virulence and antibiotic resistance markers expression in clinical enteropathogenic Escherichia (E.) coli strains. The 7 clinical enteropathogenic E. coli strains, one standard E. coli ATCC 25,922 and one Bacillus (B.) cereus strains were cultivated in nutrient broth, aerobically at 37 °C, for 24 h. The E. faecium CMGB16 probiotic strain was cultivated in anaerobic conditions, at 37 °C in MRS (Man Rogosa Sharpe) broth, and co-cultivated with two pathogenic strains (B. cereus and E. coli O28) culture fractions (supernatant, washed sediment and heat-inactivated culture) for 6 h, at 37 °C. After co-cultivation, the soluble and cellular fractions of the probiotic strain cultivated in the presence of two pathogenic strains were separated by centrifugation (6000 rpm, 10 min), heat-inactivated (15 min, 100 °C) and co-cultivated with the clinical enteropathogenic E. coli strains in McConkey broth, for 24 h, at 37 °C, in order to investigate the influence of the probiotic fractions on the adherence capacity and antibiotic susceptibility. All tested probiotic combinations influenced the adherence pattern of E. coli tested strains. The enteropathogenic E. coli strains susceptibility to aminoglycosides, beta-lactams and quinolones was increased by all probiotic combinations and decreased for amoxicillin-clavulanic acid. This study demonstrates that the plurifactorial anti-infective action of probiotics is also due to the modulation of virulence factors and antibiotic susceptibility expression in E. coli pathogenic strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characterization of veterinary hospital-associated isolates of Enterococcus species in Korea.

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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.

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

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François Lebreton

Full Text Available 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

Utilization of tannery fleshings: Optimization of conditions for fermenting delimed tannery fleshings using Enterococcus faecium HAB01 by response surface methodology.

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Kumar Rai, Amit; General, Thiyam; Bhaskar, N; Suresh, P V; Sakhare, P Z; Halami, P M; Gowda, Lalitha R; Mahendrakar, N S

2010-03-01

Conditions for fermentation of delimed tannery fleshings--to obtain higher degree of protein hydrolysis and reasonably better antioxidant activity--using Enterococcus faecium HAB01 (GenBank #FJ418568) were optimized. Three independent variables--viz., inoculum level (X1), glucose level (X2) and fermentation time (X3)--were optimized using response surface method considering degree of hydrolysis (DH; %) and total titrable acidity (TTA) as response variables. The optimized conditions were found to be 12.5% (v/w) inoculum, 17.5% (w/w) glucose and 96h of fermentation at 37+/-1 degrees C to obtain a maximum DH%. The usefulness of the predicted model was further validated by considering random combinations of the independent factors. The chemical score of the hydrolysate revealed an excess amount of essential amino acids, viz., arginine and leucine compared to reference protein. The liquor portion had relatively high antioxidant activities, indicating its potential for use as a high value feed ingredient. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Intestinal Structure and Function of Broiler Chickens on Diets Supplemented with a Synbiotic Containing Enterococcus faecium and Oligosaccharides

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Wageha Awad

2008-11-01

Full Text Available A feeding trial was conducted on broiler chickens to study the effects of the synbiotic BIOMIN IMBO [a combination of Enterococcus faecium, a prebiotic (derived from chicory and immune modulating substances (derived from sea algae], with a dose of 1 kg/ton of the starter diets and 0.5 kg/ton of the grower diets on the intestinal morphometry and nutrient absorption. The general performance was improved (P < 0.05 by the dietary inclusion of synbiotic compared with the controls. Furthermore, the addition of synbiotic increased (P < 0.001 the villus height/crypt depth ratio and villus height in ileum. However, the ileal crypt depth was decreased by dietary supplementation of synbiotic compared with control. The addition of glucose in Ussing chamber produced a significant increase (P ≤ 0.001 in short-circuit current (Isc in jejunum and colon relative to the basal values in both synbiotic and control groups. However, in jejunum the percentage of Isc increase after glucose addition was higher for synbiotic group (333 % than control group (45 %. In conclusion, dietary inclusion of synbiotic BIOMIN IMBO increased the growth performance and improved intestinal morphology and nutrient absorption.

Estudio de actinomicetos marinos aislados de la costa central del Perú y su actividad antibacteriana frente a Staphylococcus aureus Meticilina Resistentes y Enterococcus faecalis Vancomicina Resistentes Study of marine actinomycetes isolated from the central coast of Peru and their antibacterial activity against Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococcus faecalis

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Jorge León

2011-06-01

Full Text Available Objetivos. Determinar el potencial antimicrobiano de actinomicetos marinos frente a cepas S. aureus meticilino-resistentes (MRSA y E. faecalis vancomicina-resistentes (VRE. Materiales y métodos. En dos medios de cultivo se sembraron 29 cepas de actinomicetos aislados de sedimento marino. Se evaluó la capacidad inhibitoria mediante pruebas de antagonismo in vitro para MRSA y VRE. Se procesó los extractos orgánicos de tres actinomicetos seleccionados para determinar la Concentración Mínima Inhibitoria (CMI del compuesto activo. Resultados. La mayoría de los actinomicetos aislados correspondieron a un grupo homogéneo de blanco-grisáceos (62% con buen nivel de crecimiento en agar marino. Los porcentajes inhibitorios fueron superiores a 85% para ambos patógenos con halos de inhibición mayores a 69 y 78 mm de diámetro para MRSA y VRE respectivamente. Los extractos diclorometánicos de tres de los actinomicetos aislados (I-400A, B1-T61, M10-77 mostraron gran potencial inhibitorio de ambos patógenos, siendo M10-77 la cepa de actinomiceto de mayor actividad antibiótica frente a S. aureus ATCC 43300 resistente a meticilina y E. faecalis ATCC 51299 resistente a vancomicina con una Concentración Mínima Inhibitoria (CMI de 7,9 y 31,7 μg/ mL respectivamente. El análisis filogenético de la cepa M10- 77 presenta un 99% de similaridad con la especie marina Streptomyces erythrogriseus. Conclusiones. El sedimento marino de la costa central del Perú es fuente promisorio de cepas de actinomicetos con gran capacidad de producir compuestos bioactivos capaces de inhibir patógenos tipificados como multidrogo-resistentes tales como S. aureus meticilino resistentes y E. faecalis vancomicina resistentes.Objectives. To determine the antimicrobial potential of marine actinomycetes against drug-resistant pathogens represented by strains of methicillin-resistant Staphylococcus aureus (MRSA and vancomycin-resistant Enterococcus faecalis (VRE. Materials and

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

DEFF Research Database (Denmark)

Emborg, Hanne-Dorthe; Andersen, J. S.; Seyfarth, Anne Mette

2003-01-01

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...

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

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Charlene Desbonnet

2016-04-01

Full Text Available 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.

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

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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. Copyright 2000 The Hospital Infection Society.

Comparison of two methods for purification of enterocin B, a bacteriocin produced by Enterococcus faecium W3.

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Dündar, Halil; Atakay, Mehmet; Çelikbıçak, Ömür; Salih, Bekir; Bozoğlu, Faruk

2015-01-01

This study aimed to compare two different approaches for the purification of enterocin B from Enterococcus faecium strain W3 based on the observation that the bacteriocin was found both in cell associated form and in culture supernatant. The first approach employed ammonium sulfate precipitation, cation-exchange chromatography, and sequential reverse-phase high-performance liquid chromatography. The latter approach exploited a pH-mediated cell adsorption-desorption method to extract cell-bound bacteriocin, and one run of reverse-phase chromatography. The first method resulted in purification of enterocin B with a recovery of 4% of the initial bacteriocin activity found in culture supernatant. MALDI-TOF MS analysis and de novo peptide sequencing of the purified bacteriocin confirmed that the active peptide was enterocin B. The second method achieved the purification of enterocin B with a higher recovery (16%) and enabled us to achieve pure bacteriocin within a shorter period of time by avoiding time consuming purification protocols. The purity and identity of the active peptide were confirmed again by matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF) mass spectrometry (MS) analysis. Although both approaches were satisfactory to obtain a sufficient amount of enterocin B for use in MS and amino acid sequence analysis, the latter was proved to be applicable in large-scale and rapid purification of enterocin B.

Atividade antimicrobiana in vitro de quinupristina/dalfopristina para cocos gram-positivos isolados de cinco centros brasileiros: resultado do estudo de vigilância L-SMART Antimicrobial in vitro activity of quinupristin/dalfopristin against gram-positive cocci isolated from 5 Brazilian centers: results from the local smart (L-SMART surveillance study

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Caio Mendes

2002-07-01

Full Text Available Há alguns anos tem-se verificado um aumento progressivo da resistência de alguns cocos gram-positivos a determinados antimicrobianos. Este aumento da resistência tem sido observado principalmente no ambiente hospitalar, e as bactérias mais comumente envolvidas são os Staphylococcus spp. e os Enterococcus spp. Devido a este fato, novos antimicrobianos são avaliados para o tratamento de infecções causadas por estas cepas multirresistentes. A associação quinupristina/dalfopristina (Q/D, também conhecida como Synercid®, é um antibacteriano da classe das estreptograminas, de uso endovenoso, composto por dois derivados semi-sintéticos da pristinamicina. A combinação das estreptograminas B e A na razão de 30:70 tem atividade antimicrobiana voltada para cocos gram--positivos, como Staphylococcus spp., Streptococcus spp., incluindo S. pneumoniae e Enterococcus faecium, sendo o E. faecalis habitualmente resistente. Neste estudo foi avaliada a atividade in vitro de Q/D e outros oito antimicrobianos frente a 631 amostras de cocos gram-positivos isoladas de cinco centros brasileiros, complementadas com outras 20 cepas de E. faecium resistentes à vancomicina, provenientes dos Estados Unidos. Para a avaliação da sensibilidade aos antimicrobianos foi determinada a concentração inibitória mínima (MIC pelo método do Etest (AB Biodisk, Solna, Suécia e as cepas testadas foram: Staphylococcus aureus (n = 267, Staphylococcus coagulase negativo (n = 131, Streptococcus pneumoniae (n = 130, Streptococcus beta-hemolíticos (n = 28, Enterococcus faecalis (n = 44 e E. faecium (n = 51. A Q/D demonstrou excelente atividade contra Staphylococcus spp., independente de serem sensíveis ou resistentes à oxacilina. Para S. pneumoniae, a Q/D apresentou igualmente uma ótima atividade, inclusive para as cepas com resistência intermediária ou total para penicilina. Entre as cepas de E. faecium sensíveis à vancomicina, o MIC90 de Q/D obtido foi de 3µg

[Influence of staphylococcin T on Enterococcus sp. growth].

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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.

Avaliação da suscetibilidade antimicrobiana de bactérias anaeróbias facultativas isoladas de canais radiculares de dentes com insucesso endodôntico frente aos antibióticos de uso sistêmico

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Bárbara Trindade Di Santi

Full Text Available ResumoIntroduçãoBactérias associadas ao insucesso do tratamento endodôntico são capazes de adquirir e expressar resistência aos agentes antimicrobianos comumente empregados para tratar infecções, o que torna necessário, em determinadas situações, a realização de testes laboratoriais para detectar a resistência ou a suscetibilidade antimicrobiana desses micro-organismos.Objetivoavaliar a suscetibilidade antimicrobiana das cepas de Enterococcus faecalis, Enterococcus faecium, Actinomyces viscosus e Staphylococcus aureus isoladas de canais radiculares de dentes com insucesso endodôntico.Material e métodoCepas clínicas de Enterococcus faecalis (n=3, Enterococcus faecium (n=3, Actinomyces viscosus (n=3 e Staphylococcus aureus (n=3, coletadas in vivo de canais radiculares com insucesso endodôntico, foram testadas quanto à suscetibilidade antimicrobiana por meio do método E-test em duplicata, utilizando os antibióticos: Amoxicilina (AC, Rifampicina (RI, Moxifloxacina (MX, Vancomicina (VA, Tetraciclina (TC, Ciprofloxacina (CI, Cloranfenicol (CL, Benzilpenicilina (PG, Amoxicilina + ácido clavulânico (XL, Doxiciclina (DC, Eritromicina (EM e Azitromicina (AZ.ResultadoTodas as cepas clínicas testadas foram suscetíveis aos antibióticos AC, XL, PG, DC, MX, TC e VA. Todos os isolados das espécies de S. aureus foram suscetíveis aos 12 antibióticos testados. As cepas de E. faecalis, E. faecium e A. viscosus mostraram padrão de suscetibilidade intermediário contra EM. Algumas cepas de E. faecalis e E. faecium foram resistentes a AZ e RI.ConclusãoAs cepas clínicas isoladas dos canais radiculares de dentes com insucesso endodôntico mostraram perfis diferentes de suscetibilidade antimicrobiana e nenhum isolado de E. faecalis e E. faeciumapresentou-se suscetível a AZ e EM.

Safety Evaluation of Enterocin Producer Enterococcus sp. Strains Isolated from Traditional Turkish Cheeses.

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Avcı, Mine; Özden Tuncer, Banu

2017-07-06

The purpose of this study was to determine the antimicrobial activity and occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate some of their virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. Structural genes entA, entB, entP and entX were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated anyβ-haemolytic activity and only one strain had gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was detected only in this strain.

Reduced susceptibility of Enterococcus spp. isolates from Cairo University Hospital to tigecycline: Highlight on the influence of proton pump inhibitors.

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Hassan, Reem Mostafa; Ghaith, Doaa Mohammad; Ismail, Dalia Kadry; Zafer, Mai Mahmoud

2018-03-01

The incidence of reduced susceptibility to tigecycline (TIG) is increasing. This study aimed to analyse the in vitro activity of TIG against Enterococcus spp. isolates recovered from hospitalised patients and to evaluate the effect of omeprazole on the in vitro antimicrobial activity of TIG against several enterococcal species. A total of 67 Enterococcus clinical isolates were identified by MALDI-TOF/MS and multiplex PCR. Minimum inhibitory concentrations (MICs) of TIG alone and in combination with omeprazole (10, 30 and 60mg/L) were determined by broth microdilution. Antibiotic susceptibility to other antibiotics was determined by disk diffusion. The presence of van, tet(X) and tet(X1) genes was tested by multiplex PCR. Of the 67 Enterococcus isolates, 2 (3.0%) were resistant to TIG and 13 (19.4%) were intermediate-resistant according to EUCAST. The frequencies of resistance to norfloxacin (80.6%), doxycycline (80.6%), levofloxacin (74.6%) and ciprofloxacin (71.6%) were highest, whilst that of vancomycin (25.4%) was lowest. The vanA gene was detected in 11 Enterococcus isolates (8 Enterococcus faecalis, 3 Enterococcus faecium), vanB in 3 Enterococcus isolates (2 E. faecium, 1 E. faecalis) and vanC-2/3 in 3 Enterococcus casseliflavus. Nine isolates (13.4%) were positive for tet(X1). TIG resistance occurred both in patients receiving or not TIG and/or omeprazole. Omeprazole increased TIG MICs by 4-128-fold. The possibility of selection of TIG-non-susceptible Enterococcus in the gut may occur with long-term use of omeprazole. Omeprazole influenced TIG activity in a concentration-dependent manner. To our knowledge; this is the first report of TIG-non-susceptible Enterococcus spp. in Egypt. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Effect of a probiotic beverage consumption (Enterococcus faecium CRL 183 and Bifidobacterium longum ATCC 15707 in rats with chemically induced colitis.

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Larissa Sbaglia Celiberto

Full Text Available Some probiotic strains have the potential to assist in relieving the symptoms of inflammatory bowel disease. The impact of daily ingestion of a soy-based product fermented by Enterococcus faecium CRL 183 and Lactobacillus helveticus 416 with the addition of Bifidobacterium longum ATCC 15707 on chemically induced colitis has been investigated thereof within a period of 30 days.Colitis was induced by dextran sulfate sodium. The animals were randomly assigned into five groups: Group C: negative control; Group CL: positive control; Group CLF: DSS with the fermented product; Group CLP: DSS with the non-fermented product (placebo; Group CLS: DSS with sulfasalazine. The following parameters were monitored: disease activity index, fecal microbial analyses, gastrointestinal survival of probiotic microorganisms and short-chain fatty acids concentration in the feces. At the end of the protocol the animals' colons were removed so as to conduct a macroscopical and histopathological analysis, cytokines and nitrite quantification.Animals belonging to the CLF group showed fewer symptoms of colitis during the induction period and a lower degree of inflammation and ulceration in their colon compared to the CL, CLS and CLP groups (p<0.05. The colon of the animals in groups CL and CLS presented severe crypt damage, which was absent in CLF and CLP groups. A significant increase in the population of Lactobacillus spp. and Bifidobacterium spp. at the end of the protocol was verified only in the CLF animals (p<0.05. This group also showed an increase in short-chain fatty acids (propionate and acetate. Furthermore, the intestinal survival of E. faecium CRL 183 and B. longum ATCC 15707 in the CLF group has been confirmed by biochemical and molecular analyzes.The obtained results suggest that a regular intake of the probiotic product, and placebo to a lesser extent, can reduce the severity of DSS-induced colitis on rats.

Production of Enterocins L50A, L50B, and IT, a New Enterocin, by Enterococcus faecium IT62, a Strain Isolated from Italian Ryegrass in Japan▿

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Izquierdo, Esther; Bednarczyk, Audrey; Schaeffer, Christine; Cai, Yimin; Marchioni, Eric; Van Dorsselaer, Alain; Ennahar, Saïd

2008-01-01

Enterococcus faecium IT62, isolated from ryegrass in Japan, was shown to produce three different bacteriocins, two of which had molecular masses and amino acid sequences that corresponded to those of enterocin L50A and enterocin L50B. These peptides existed, however, as chemically modified forms that were either N formylated or N formylated and oxidized at Met24. The third bacteriocin, named enterocin IT, had a molecular mass of 6,390 Da, was made up of 54 amino acids, and did not correspond to any known bacteriocin. However, enterocin IT was identical to the C-terminal part of the 16-amino-acid-longer bacteriocin 32 (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). For the first time, the antimicrobial activity spectra for enterocins L50A and L50B were determined separately and included a wide range of gram-positive bacteria but also a few gram-negative strains that were weakly sensitive. Slight differences in the activities of enterocins L50A and L50B were observed, as gram-positive bacteria showed an overall higher level of sensitivity to L50A than to L50B, as opposed to gram-negative ones. Conversely, enterocin IT showed a very narrow antimicrobial spectrum that was limited to E. faecium strains, one strain of Bacillus subtilis, and one strain of Lactococcus lactis. This study showed that E. faecium IT62, a grass-borne strain, produces bacteriocins with very different activity features and structures that may be found in strains associated with food or those of clinical origin, which demonstrates that a particular enterocin structure may be widespread and not related to the producer's origin. PMID:18391036

Production of enterocins L50A, L50B, and IT, a new enterocin, by Enterococcus faecium IT62, a strain isolated from Italian ryegrass in Japan.

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Izquierdo, Esther; Bednarczyk, Audrey; Schaeffer, Christine; Cai, Yimin; Marchioni, Eric; Van Dorsselaer, Alain; Ennahar, Saïd

2008-06-01

Enterococcus faecium IT62, isolated from ryegrass in Japan, was shown to produce three different bacteriocins, two of which had molecular masses and amino acid sequences that corresponded to those of enterocin L50A and enterocin L50B. These peptides existed, however, as chemically modified forms that were either N formylated or N formylated and oxidized at Met(24). The third bacteriocin, named enterocin IT, had a molecular mass of 6,390 Da, was made up of 54 amino acids, and did not correspond to any known bacteriocin. However, enterocin IT was identical to the C-terminal part of the 16-amino-acid-longer bacteriocin 32 (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). For the first time, the antimicrobial activity spectra for enterocins L50A and L50B were determined separately and included a wide range of gram-positive bacteria but also a few gram-negative strains that were weakly sensitive. Slight differences in the activities of enterocins L50A and L50B were observed, as gram-positive bacteria showed an overall higher level of sensitivity to L50A than to L50B, as opposed to gram-negative ones. Conversely, enterocin IT showed a very narrow antimicrobial spectrum that was limited to E. faecium strains, one strain of Bacillus subtilis, and one strain of Lactococcus lactis. This study showed that E. faecium IT62, a grass-borne strain, produces bacteriocins with very different activity features and structures that may be found in strains associated with food or those of clinical origin, which demonstrates that a particular enterocin structure may be widespread and not related to the producer's origin.

Prevalence and antibiotic resistance of Enterococcus spp. isolated from retail cheese, ready-to-eat salads, ham, and raw meat.

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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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Combined effect of enterocin and lipase from Enterococcus faecium NCIM5363 against food borne pathogens: mode of action studies.

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Ramakrishnan, Vrinda; Narayan, Bhaskar; Halami, Prakash M

2012-08-01

Food borne diseases have a major impact on public health whose epidemiology is rapidly changing. The whole cells of pathogens involved or their toxins/metabolites affect the human health apart from spoiling sensory properties of the food products finally affecting the food industry as well as consumer health. With pathogens developing mechanisms of antibiotic resistance, there has been an increased need to replace antibiotics as well as chemical additives with naturally occurring bacteriocins. Bacteriocins are known to act mainly against Gram-positive pathogens and with little or no effect towards Gram-negative enteric bacteria. In the present study, combination effect of lipase and bacteriocin produced by Enterococcus faecium NCIM5363, a highly lipolytic lactic acid bacterium against various food pathogens was assessed. The lipase in combination with enterocin exhibited a lethal effect against Gram-negative pathogens. Scanning electron microscopy studies carried out to ascertain the constitutive mode of action of lipase and enterocin revealed that the lipase degrades the cell wall of Gram-negative bacteria and creates a pore through which enterocin enters thereby resulting in cell death. The novelty of this work is the fact that this is the first report revealing the synergistic effect of lipase with enterocin against Gram-negative bacteria.

Prevalence and antibiotic resistance of Enterococcus strains isolated from poultry.

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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.

Rapid disc diffusion antibiotic susceptibility testing for Pseudomonas aeruginosa, Acinetobacter baumannii and Enterococcus spp.

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Hombach, Michael; Jetter, Marion; Blöchliger, Nicolas; Kolesnik-Goldmann, Natalia; Keller, Peter M; Böttger, Erik C

2018-01-01

Abstract Background We investigated the feasibility of rapid disc diffusion antibiotic susceptibility testing (rAST) with reading of inhibition zones after 6 and/or 8 h of incubation for Enterococcus faecalis, Enterococcus faecium, Pseudomonas aeruginosa and Acinetobacter baumannii. In addition, we evaluated discrimination of resistant populations from the WT populations at early timepoints and the requirement for clinical breakpoint adaptations for proper interpretation of rAST data. Methods In total, 815 clinical strains [E. faecalis (n = 135), E. faecium (n = 227), P. aeruginosa (n = 295) and A. baumannii (n = 158)] were included in this study. Disc diffusion plates were streaked, incubated and imaged using the WASPLabTM automation system. WT populations and non-WT populations were defined using epidemiological cut-offs. Results and conclusions rAST at 6 and 8 h was possible for A. baumannii and enterococci with readability of inhibition zones >90%. Overall categorical agreement of rAST at 6 h with AST at 18 h was 97.2%, 97.4% and 95.3% for E. faecalis, E. faecium and A. baumannii, respectively. With few exceptions, major categorization error rates were <1% for A. baumannii, and vancomycin-resistant E. faecium were clearly separated from the WT at 6 h. For P. aeruginosa the average readability of inhibition zones was 68.9% at 8 h and we found an overall categorical agreement of 94.8%. Adaptations of clinical breakpoints and/or introduction of technical buffer zones, preferably based on aggregated population data from various epidemiological settings, are required for proper interpretation of rAST. PMID:29186434

Patrones de resistencia a antibióticos de enterococos aislados de aguas estuarinas Antibiotic resistance patterns of enterococci isolated from estuarine waters

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M. Baldini

2008-03-01

Full Text Available La llegada al ambiente de bacterias antibiótico-resistentes compromete su calidad higiénico sanitaria. Se analizó la prevalencia de diferentes especies de Enterococcus en aguas del estuario de Bahía Blanca y sus patrones de resistencia a los antibióticos. Se identificaron bioquímicamente 103 aislamientos . Para evaluar la resistencia a antibióticos se implementó la técnica de difusión en agar utilizando discos de vancomicina (Van 30 µg, gentamicina (GenH 120 µg, estreptomicina (StrH 300 µg, teicoplanina (T 30 µg, ampicilina (Am 10 µg y ciprofloxacina (CIP 5 µg, según normas del Clinical and Laboratory Standards Institute. Se identificaron siete especies de Enterococcus; Enterococcus faecium y Enterococcus faecalis resultaron ser las más frecuentes. El 1,9% de los enterococos presentó resistencia de alto nivel a los aminoglucósidos y no hubo aislamientos con resistencia simultánea a StrH y GenH. El 12,6% de los aislamientos resultó resistente a CIP. No se detectaron resistencias a los glucopéptidos, ni a la Am. El 34% de los aislamientos fue sensible a todos los antibióticos probados. Tradicionalmente, la vigilancia de la dispersión de resistencias bacterianas se realiza con microorganismos de muestras clínicas. Los hallazgos de este trabajo constituyen un dato relevante para el control de cepas resistentes, las que se creían circunscriptas al ámbito hospitalario y que, sin embargo, se encuentran circulando en el ambiente.The introduction of antibioticresistant bacteria to the environment, affects its hygienic-sanitary quality. The objective of this work is to study the prevalence and the antibiotic resistance patterns of enterococci species isolated from Bahía Blanca estuarine waters. One hundred and three isolates were biochemically identified as Enterococcus spp. The diffusion technique was implemented, by using disks of: vancomycin (Van 30 µg, gentamicin (GenH 120 µg, streptomycin (StrH 300 µg, teicoplanin (T

Identification and tracing of Enterococcus spp. by RAPD-PCR in traditional fermented sausages and meat environment.

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Martín, B; Corominas, L; Garriga, M; Aymerich, T

2009-01-01

Four local small-scale factories were studied to determine the sources of enterococci in traditional fermented sausages. Different points during the production of a traditional fermented sausage type (fuet) were evaluated. Randomly amplified polymorphic DNA (RAPD)-PCR was used to type 596 Enterococcus isolates from the final products, the initial meat batter, the casing, the workers' hands and the equipment. Species-specific PCR-multiplex and the partial sequencing of atpA gene and 16S rRNA gene sequencing allowed the identification of the isolates: Enterococcus faecalis (31.4%), Enterococcus faecium (30.7%), Enterococcus sanguinicola (14.9%), Enterococcus devriesei (9.7%), Enterococcus malodoratus (7.2%), Enterococcus gilvus (1.0%), Enterococcus gallinarum (1.3%), Enterococcus casseliflavus (3.4%), Enterococcus hermanniensis (0.2%), and Enterococcus durans (0.2%). A total of 92 different RAPD-PCR profiles were distributed among the different factories and samples evaluated. Most of the genotypes found in fuet samples were traced back to their source. The major sources of enterococci in the traditional fermented sausages studied were mainly the equipment followed by the raw ingredients, although a low proportion was traced back to human origin. This work contributes to determine the source of enterococcal contamination in fermented sausages and also to the knowledge of the meat environment.

Purification and characterization of enterocin 62-6, a two-peptide bacteriocin produced by a vaginal strain of Enterococcus faecium: Potential significance in bacterial vaginosis

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Dezwaan, Diane C.; Mequio, Michael J.; Littell, Julia S.; Allen, Jonathan P.; Rossbach, Silvia; Pybus, Vivien

2009-01-01

A bacteriocin produced by a vaginal isolate of Enterococcus faecium strain 62-6, designated enterocin 62-6, was characterized following purification and DNA sequence analysis and compared to previously described bacteriocins. Enterocin 62-6 was isolated from brain heart infusion (BHI) culture supernatants using ammonium sulfate precipitation followed by elution from a Sepharose cation exchange column using a continuous salt gradient (0.1–0.7 M NaCl). SDS-PAGE of an active column fraction resulted in an electrophoretically pure protein, which corresponded to the growth inhibition of the sensitive Lactobacillus indicator strain in the gel overlay assay. Purified enterocin 62-6 was shown to be heat- and pH-stable, and sensitive to the proteolytic enzymes α-chymotrypsin and pepsin. Results from mass spectrometry suggested that it comprised two peptides of 5206 and 5219±1 Da, which was confirmed by DNA sequence analysis. The characteristics of enterocin 62-6 as a small, heat- and pH-stable, cationic, hydrophobic, two-peptide, plasmid-borne bacteriocin, with an inhibitory spectrum against a broad range of Gram-positive but not Gram-negative bacteria, were consistent with its classification as a class IIc bacteriocin. Furthermore, its wide spectrum of growth inhibitory activity against Gram-positive bacteria of vaginal origin including lactobacilli, and stability under the acidic conditions of the vagina, are consistent with our hypothesis that it could have potential significance in disrupting the ecology of the vaginal tract and pave the way for the establishment of the abnormal microbiota associated with the vaginal syndrome bacterial vaginosis. This is the first class IIc bacteriocin produced by a strain of E. faecium of vaginal origin to be characterized. PMID:19578555

Avaliação do simbiótico fermentado com Enterococcus faecium CRL 183 e Lactobacillus helveticus ssp jugurti 416, à base de extratos aquosos de soja e de yacon (Smallanthus sonchifolius) no controle do desenvolvimento do Diabetes Mellitus

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Roselino, Mariana Nougalli [UNESP

2012-01-01

O presente trabalho avaliou os efeitos do simbiótico fermentado com Enterococcus faecium CRL 183 e Lactobacillus helveticus ssp jugurti 416, à base de extratos de soja e de yacon produzidos em ratos com Diabetes mellitus, cuja indução foi feita quimicamente pela administração intraperitoneal de estreptozotocina (50mg/kg de peso corporal). Os animais foram divididos em quatro grupos experimentais (n=10): I - animais não diabéticos que receberam somente ração (controle negativo); II - animais d...

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

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Patrick Eberechi Akpaka

Full Text Available 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.

Antimicrobial resistance of Enterococcus isolates in Turkey: A meta-analysis of current studies.

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Kilbas, Imdat; Ciftci, Ihsan Hakki

2018-03-01

In this study, a meta-analysis of Enterococcus isolates collected in 2000-2015 in Turkey and their susceptibility/resistance to antibiotics, clinical indications for initial drug treatment, and identification of alternative treatments was conducted. The meta-analysis examined antibiotic susceptibility/resistance in Enterococcus spp. isolates. The study was planned and conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Statements on antimicrobial resistance were grouped according to the antimicrobial stewardship programme (ASP). The mean resistance rates of Enterococcus faecalis to vancomycin (VAN) and linezolid (LNZ) were 1.0±2.2% and 1.9±2.6%, respectively, whereas the mean resistance rates of Enterococcus faecium to VAN and LNZ were 10.3±11.3% and 2.4±0%, respectively. This study is the first meta-analysis of the resistance of clinical Enterococcus isolates in Turkey to antimicrobial agents, which is a major problem stemming from the excessive usage of antibiotics. The development of antibiotic resistance in Turkey has changed over time. To support the practice of evidence-based medicine, more notifications about Enterococcus resistance status are needed, especially notifications following ASP rules. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

Multidrug resistance in Enterococcus species of faecal origin from commercial dairy lactating cattle: Public health concern

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Godfred Ngu Tanih

2017-11-01

Full Text Available Objective: To evaluate the prevalence of Enterococcus species in cattle faeces, their corresponding drug resistant patterns as well as the genes coding for resistance in the isolates. Methods: Two hundred and ninety rectal swabs were cultured for the isolation of Enterococcus. Presumptive isolates were confirmed by PCR, targeting the tuf gene, and confirmed isolates were identified to species level, using species-specific primers aimed at targeting six different species. Additionally, antibiogram was performed by disc diffusion and genes implicated in resistance were evaluated using molecular methods. Results: All presumptive isolates were confirmed as Enterococcus and speciated as: Enterococcus hirae (82%, Enterococcus faecium (5%, Enterococcus durans (5%, Enterococcus faecalis (2% and 6% of unidentified species. Resistance to various antimicrobials ranged from 16.4% for penicillin to 69.6% for erythromycin. Among the tetracycline and erythromycin-resistant isolates, tet M (100% and erm B (29% were the only amplified genes known to mediate resistance respectively. Other detected genes included van B (25%, van C1 (21% and bla Z (11%. Conclusions: A high prevalence of multidrug resistant Enterococcus species was observed in this study, accentuating the need to improve on animal farming practices to prevent the dissemination of this microorganism to the environment.

Development of a Chemically Defined Medium for Better Yield and Purification of Enterocin Y31 from Enterococcus faecium Y31

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Wenli Liu

2017-01-01

Full Text Available The macro- and micronutrients in traditional medium, such as MRS, used for cultivating lactic acid bacteria, especially for bacteriocin production, have not been defined, preventing the quantitative monitoring of metabolic flux during bacteriocin biosynthesis. To enhance Enterocin Y31 production and simplify steps of separation and purification, we developed a simplified chemically defined medium (SDM for the growth of Enterococcus faecium Y31 and production of its bacteriocin, Enterocin Y31. We found that the bacterial growth was unrelated to Enterocin Y31 production in MRS; therefore, both the growth rate and the Enterocin Y31 production were set as the index for investigation. Single omission experiments revealed that 5 g/L NaCl, five vitamins, two nucleic acid bases, MgSO4·7H2O, MnSO4·4H2O, KH2PO4, K2HPO4, CH3COONa, fourteen amino acids, and glucose were essential for the strain’s growth and Enterocin Y31 production. Thus, a novel simplified and defined medium (SDM was formulated with 30 components in total. Consequently, Enterocin Y31 production yield was higher in SDM as compared to either MRS or CDM. SDM improved the Enterocin Y31 production and simplified the steps of purification (only two steps, which has broad potential applications.

Characterization and Heterologous Expression of the Genes Encoding Enterocin A Production, Immunity, and Regulation in Enterococcus faecium DPC1146

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O’Keeffe, Triona; Hill, Colin; Ross, R. Paul

1999-01-01

Enterocin A is a small, heat-stable, antilisterial bacteriocin produced by Enterococcus faecium DPC1146. The sequence of a 10,879-bp chromosomal region containing at least 12 open reading frames (ORFs), 7 of which are predicted to play a role in enterocin biosynthesis, is presented. The genes entA, entI, and entF encode the enterocin A prepeptide, the putative immunity protein, and the induction factor prepeptide, respectively. The deduced proteins EntK and EntR resemble the histidine kinase and response regulator proteins of two-component signal transducing systems of the AgrC-AgrA type. The predicted proteins EntT and EntD are homologous to ABC (ATP-binding cassette) transporters and accessory factors, respectively, of several other bacteriocin systems and to proteins implicated in the signal-sequence-independent export of Escherichia coli hemolysin A. Immediately downstream of the entT and entD genes are two ORFs, the product of one of which, ORF4, is very similar to the product of the yteI gene of Bacillus subtilis and to E. coli protease IV, a signal peptide peptidase known to be involved in outer membrane lipoprotein export. Another potential bacteriocin is encoded in the opposite direction to the other genes in the enterocin cluster. This putative bacteriocin-like peptide is similar to LafX, one of the components of the lactacin F complex. A deletion which included one of two direct repeats upstream of the entA gene abolished enterocin A activity, immunity, and ability to induce bacteriocin production. Transposon insertion upstream of the entF gene also had the same effect, but this mutant could be complemented by exogenously supplied induction factor. The putative EntI peptide was shown to be involved in the immunity to enterocin A. Cloning of a 10.5-kb amplicon comprising all predicted ORFs and regulatory regions resulted in heterologous production of enterocin A and induction factor in Enterococcus faecalis, while a four-gene construct (entAITD) under the

Proteomic characterization of vanA-containing Enterococcus recovered from Seagulls at the Berlengas Natural Reserve, W Portugal.

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Radhouani, Hajer; Poeta, Patrícia; Pinto, Luís; Miranda, Júlio; Coelho, Céline; Carvalho, Carlos; Rodrigues, Jorge; López, María; Torres, Carmen; Vitorino, Rui; Domingues, Pedro; Igrejas, Gilberto

2010-09-21

Enterococci have emerged as the third most common cause of nosocomial infections, requiring bactericidal antimicrobial therapy. Although vancomycin resistance is a major problem in clinics and has emerged in an important extend in farm animals, few studies have examined it in wild animals. To determine the prevalence of vanA-containing Enterococcus strains among faecal samples of Seagulls (Larus cachinnans) of Berlengas Natural Reserve of Portugal, we developed a proteomic approach integrated with genomic data. The purpose was to detect the maximum number of proteins that vary in different enterococci species which are thought to be connected in some, as yet unknown, way to antibiotic resistance. From the 57 seagull samples, 54 faecal samples showed the presence of Enterococcus isolates (94.7%). For the enterococci, E. faecium was the most prevalent species in seagulls (50%), followed by E. faecalis and E. durans (10.4%), and E. hirae (6.3%). VanA-containing enterococcal strains were detected in 10.5% of the 57 seagull faecal samples studied. Four of the vanA-containing enterococci were identified as E. faecium and two as E. durans. The tet(M) gene was found in all five tetracycline-resistant vanA strains. The erm(B) gene was demonstrated in all six erythromycin-resistant vanA strains. The hyl virulence gene was detected in all four vanA-containing E. faecium isolates in this study, and two of them harboured the purK1 allele. In addition these strains also showed ampicillin and ciprofoxacin resistance. The whole-cell proteomic profile of vanA-containing Enterococcus strains was applied to evaluate the discriminatory power of this technique for their identification. The major differences among species-specific profiles were found in the positions corresponding to 97-45 kDa. Sixty individualized protein spots for each vanA isolate was identified and suitable for peptide mass fingerprinting measures by spectrometry measuring (MALDI/TOF MS) and their identification

Proteomic characterization of vanA-containing Enterococcus recovered from Seagulls at the Berlengas Natural Reserve, W Portugal

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Coelho Céline

2010-09-01

Full Text Available Abstract Background Enterococci have emerged as the third most common cause of nosocomial infections, requiring bactericidal antimicrobial therapy. Although vancomycin resistance is a major problem in clinics and has emerged in an important extend in farm animals, few studies have examined it in wild animals. To determine the prevalence of vanA-containing Enterococcus strains among faecal samples of Seagulls (Larus cachinnans of Berlengas Natural Reserve of Portugal, we developed a proteomic approach integrated with genomic data. The purpose was to detect the maximum number of proteins that vary in different enterococci species which are thought to be connected in some, as yet unknown, way to antibiotic resistance. Results From the 57 seagull samples, 54 faecal samples showed the presence of Enterococcus isolates (94.7%. For the enterococci, E. faecium was the most prevalent species in seagulls (50%, followed by E. faecalis and E. durans (10.4%, and E. hirae (6.3%. VanA-containing enterococcal strains were detected in 10.5% of the 57 seagull faecal samples studied. Four of the vanA-containing enterococci were identified as E. faecium and two as E. durans. The tet(M gene was found in all five tetracycline-resistant vanA strains. The erm(B gene was demonstrated in all six erythromycin-resistant vanA strains. The hyl virulence gene was detected in all four vanA-containing E. faecium isolates in this study, and two of them harboured the purK1 allele. In addition these strains also showed ampicillin and ciprofoxacin resistance. The whole-cell proteomic profile of vanA-containing Enterococcus strains was applied to evaluate the discriminatory power of this technique for their identification. The major differences among species-specific profiles were found in the positions corresponding to 97-45 kDa. Sixty individualized protein spots for each vanA isolate was identified and suitable for peptide mass fingerprinting measures by spectrometry measuring

Purification and Genetic Characterization of Enterocin I from Enterococcus faecium 6T1a, a Novel Antilisterial Plasmid-Encoded Bacteriocin Which Does Not Belong to the Pediocin Family of Bacteriocins

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Floriano, Belén; Ruiz-Barba, José L.; Jiménez-Díaz, Rufino

1998-01-01

Enterocin I (ENTI) is a novel bacteriocin produced by Enterococcus faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation. The bacteriocin is active against many olive spoilage and food-borne gram-positive pathogenic bacteria, including clostridia, propionibacteria, and Listeria monocytogenes. ENTI was purified to homogeneity by ammonium sulfate precipitation, binding to an SP-Sepharose fast-flow column, and phenyl-Sepharose CL-4B and C2/C18 reverse-phase chromatography. The purification procedure resulted in a final yield of 954% and a 170,000-fold increase in specific activity. The primary structure of ENTI was determined by amino acid and nucleotide sequencing. ENTI consists of 44 amino acids and does not show significant sequence similarity with any other previously described bacteriocin. Sequencing of the entI structural gene, which is located on the 23-kb plasmid pEF1 of E. faecium 6T1a, revealed the absence of a leader peptide at the N-terminal region of the gene product. A second open reading frame, ORF2, located downstream of entI, encodes a putative protein that is 72.7% identical to ENTI. entI and ORF2 appear to be cotranscribed, yielding an mRNA of ca. 0.35 kb. A gene encoding immunity to ENTI was not identified. However, curing experiments demonstrated that both enterocin production and immunity are conferred by pEF1. PMID:9835578

Identification of Multiple Bacteriocins in Enterococcus spp. Using an Enterococcus-Specific Bacteriocin PCR Array

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Chris Henning

2015-02-01

Full Text Available Twenty-two bacteriocin-producing Enterococcus isolates obtained from food and animal sources, and demonstrating activity against Listeria monocytogenes, were screened for bacteriocin-related genes using a bacteriocin PCR array based on known enterococcal bacteriocin gene sequences in the NCBI GenBank database. The 22 bacteriocin-positive (Bac+ enterococci included En. durans (1, En. faecalis (4, En. faecium (12, En. hirae (3, and En. thailandicus (2. Enterocin A (entA, enterocins mr10A and mr10B (mr10AB, and bacteriocin T8 (bacA were the most commonly found structural genes in order of decreasing prevalence. Forty-five bacteriocin genes were identified within the 22 Bac+ isolates, each containing at least one of the screened structural genes. Of the 22 Bac+ isolates, 15 possessed two bacteriocin genes, seven isolates contained three different bacteriocins, and three isolates contained as many as four different bacteriocin genes. These results may explain the high degree of bactericidal activity observed with various Bac+ Enterococcus spp. Antimicrobial activity against wild-type L. monocytogenes and a bacteriocin-resistant variant demonstrated bacteriocins having different modes-of-action. Mixtures of bacteriocins, especially those with different modes-of-action and having activity against foodborne pathogens, such as L. monocytogenes, may play a promising role in the preservation of food.

Biochemical and genetic characterization of enterocin A from Enterococcus faecium, a new antilisterial bacteriocin in the pediocin family of bacteriocins.

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Aymerich, T; Holo, H; Håvarstein, L S; Hugas, M; Garriga, M; Nes, I F

1996-01-01

A new bacteriocin has been isolated from an Enterococcus faecium strain. The bacteriocin, termed enterocin A, was purified to homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and mass spectrometry analysis. By combining the data obtained from amino acid and DNA sequencing, the primary structure of enterocin A was determined. It consists of 47 amino acid residues, and the molecular weight was calculated to be 4,829, assuming that the four cysteine residues form intramolecular disulfide bridges. This molecular weight was confirmed by mass spectrometry analysis. The amino acid sequence of enterocin A shared significant homology with a group of bacteriocins (now termed pediocin-like bacteriocins) isolated from a variety of lactic acid-producing bacteria, which include members of the genera Lactobacillus, Pediococcus, Leuconostoc, and Carnobacterium. Sequencing of the structural gene of enterocin A, which is located on the bacterial chromosome, revealed an N-terminal leader sequence of 18 amino acid residues, which was removed during the maturation process. The enterocin A leader belongs to the double-glycine leaders which are found among most other small nonlantibiotic bacteriocins, some lantibiotics, and colicin V. Downstream of the enterocin A gene was located a second open reading frame, encoding a putative protein of 103 amino acid residues. This gene may encode the immunity factor of enterocin A, and it shares 40% identity with a similar open reading frame in the operon of leucocin AUL 187, another pediocin-like bacteriocin. PMID:8633865

Characterization of Hospital-Associated Lineages of Ampicillin-Resistant Enterococcus faecium from Clinical Cases in Dogs and Humans

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Cindy-Love eTremblay

2013-08-01

Full Text Available Ampicillin-resistant Enterococcus faecium (ARE has rapidly emerged worldwide and is one of the most important nosocomial pathogens. However, very few reports are available on ARE isolates from canine clinical cases. The objective of this study was to characterize ARE strains of canine clinical origin from a veterinary teaching hospital in Canada and to compare them with human strains. Ten ARE strains from dogs and humans were characterized by multilocus sequence typing (MLST, pulsed field gel electrophoresis (PFGE, antibiotic susceptibility and biofilm activities, presence of rep-families, CRISPR-cas and putative virulence genes. All ARE strains (n = 10 were resistant to ciprofloxacin and lincomycin. Resistances to tetracycline (n = 6, macrolides (n = 6, and to high concentrations of gentamicin, kanamycin and streptomycin (n = 5 were also observed. Canine ARE isolates were found to be susceptible to vancomycin whereas resistance to this antibiotic was observed in human strains. Ampicillin resistance was linked to PBP5 showing mutations at 25 amino acid positions. Fluoroquinolone resistance was attributable to ParC, GyrA, and GyrB mutations. Data demonstrated that all canine ARE were acm (collagen binding protein-positive and that most harbored the efaAfm gene, encoding for a cell wall adhesin. Biofilm formation was observed in two human strains but not in canine strains. Two to five rep-families were observed per strain but no CRISPR sequences were found. A total of six STs (1, 18, 65, 202, 205, and 803 were found with one belonging to a new ST (ST803. These STs were identical or closely related to human hospital-associated lineages. This report describes for the first time the characterization of canine ARE hospital-associated strains in Canada and also supports the importance of prudent antibiotic use in veterinary medicine to avoid zoonotic spread of canine ARE.

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

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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. Copyright © 2016 Elsevier B.V. All rights reserved.

Enterococcus genus identification isolated from gastrointestinal tract of chickens after bees products application using MALDI TOF MS Biotyper

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Miroslava Kačániová

2013-10-01

Full Text Available The general objective of this study was to examine the effect of bee product on the Enterococci colonization of chickens. Bee products were administered to both feed mixtures in various amounts in addition to the control group. First experimental group was with propolis in feed mixture with the addition of 200 mg propolis per 1 kg of compound and second group was with pollen with the addition of 250 mg pollen per 1 kg of compound. In this experiment, quantitative counts of Enterococci in ceca of 49-day-old chicken (Ross 308 using classical and MALDI TOF MS Biotyper method were investigated. Counts of Enterococci on Slanetz-Bartley agar were monitored. Enterococcus cells, isolated from gastrointestinal tract, were detected using MALDI TOF MS Biotyper. Counts of CFU of Enterococci were compared in experimental and control treatments, respectively. The lowest count was detected in the control experimental group. The highest count was detected in the first experimental group where was 200 mg of propolis added to 1 kg of feed mixture. Using MALDI TOF MS Biotyper, we identified the species range of the genera Enterococcus in the intestinal tract of broiler. Detected species from the genus Enterococcus were:      E. avium, E. casseliflavus, E cecorum, E. faecalis, E. faecium, E. gallinarum, E. hirae and E. malodoratus. In the experimental groups (caecal samples were most frequent species of E. avium E. faecium and E. gallinarum.

SENSORY AND CHEMICAL ASPECTS OF FROZEN SOY YOGURT FERMENTED WITH Enterococcus faecium AND Lactobacillus jugurti

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D. P. MIGUEL

2008-09-01

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As recent studies have demonstrated the beneficial effects to health of soy yogurt fermented with E. faecium and L. jugurti, aim to offer new options of consumption or this product, the goal of this work was to present the processing of frozen soy yogurt and the evaluation of its sensory characteristics. Then compare it with the other ice creams regularly processed with cow and soymilk fermented with a mixed culture of L. delbrueckii ssp. bulgaricus and S. thermophilus and also with the non-fermented ice creams acidified with the addition of lactic acid. The effect of the lactic acid bacteria in the oxidation of the product was also evaluated. The results demonstrated that it is possible to have a frozen soy yogurt fermented with E. faecium and L. jugurti with good sensory characteristics up to a period of 180 days. The lactic bacteria were not able to stop the development of the oxidation process for a long period of storage but it did not alter the sensory characteristics of the product.

Superfícies do ambiente hospitalar como possíveis reservatórios de bactérias resistentes: uma revisão Superficies inanimadas del ambiente hospitalario como posibles reservorios de bacterias resistentes: una revisión Surfaces of the hospital environment as possible deposits of resistant bacteria: a review

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Adriana Cristina de Oliveira

2010-12-01

Full Text Available O principal objetivo deste estudo é identificar, na literatura, artigos sobre a ocorrência de contaminação das superfícies inanimadas e uma possível disseminação de bactérias resistentes no ambiente hospitalar. Realizou-se um levantamento bibliográfico de artigos publicados nas bases de dados LILACS, MEDLINE, Science Direct, SCOPUS e ISI Web of Knowledge, entre 2000 e 2008. Foram selecionados e analisados vinte e um artigos. Nos estudos analisados, realçou-se a presença de bactérias em monitores, grades de cama, mesas, torneiras, telefones, teclados de computador e outros objetos. Houve predominância de Staphylococcus aureus resistente à meticilina, Clostridium difficile, Acine-to-bacter baumannii e Enterococcus resistentes à vancomicina, sendo fator preditivo a ocupação prévia por pacientes colonizados por tais microrganismos. Verificou-se semelhança entre as cepas isoladas de pacientes colonizados e/ou infectados e as cepas do ambiente por tipificação molecular. Essas evidências reforçam a necessidade de conhecimento e controle de fontes de patógenos no ambiente hospitalar.Se objetivó identificar en la literatura artículos sobre la ocurrencia de contaminación de superficies inanimadas y la posible diseminación de bacterias resistentes en el ambiente hospitalario. Se realizó una investigación bibliográfica en las bases de datos LLILACS, MEDLINE, Science Direct, SCOPUS e ISI Web of Knowledge acerca de artículos publicados entre 2000 y 2008. Fueron seleccionados veintiún artículos. En los estudios analizados, se puso de manifiesto la presencia de bacterias en monitores, barandas de camas, mesas, canillas, teléfonos, teclados de computadora y otras. Existió predominancia de Staphylococcus aureus resistente a la meticilina, Clostridium difficile, Acinetobacter baumannii y Enterococcus resistentes a la vancomicina, resultando como factor predictivo el uso previo por parte de pacientes colonizados por tales

Biochemical and Genetic Evidence that Enterococcus faecium L50 Produces Enterocins L50A and L50B, the sec-Dependent Enterocin P, and a Novel Bacteriocin Secreted without an N-Terminal Extension Termed Enterocin Q

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Cintas, Luis M.; Casaus, Pilar; Herranz, Carmen; Håvarstein, Leiv Sigve; Holo, Helge; Hernández, Pablo E.; Nes, Ingolf F.

2000-01-01

Enterococcus faecium L50 grown at 16 to 32°C produces enterocin L50 (EntL50), consisting of EntL50A and EntL50B, two unmodified non-pediocin-like peptides synthesized without an N-terminal leader sequence or signal peptide. However, the bacteriocin activity found in the cell-free culture supernatants following growth at higher temperatures (37 to 47°C) is not due to EntL50. A purification procedure including cation-exchange, hydrophobic interaction, and reverse-phase liquid chromatography has shown that the antimicrobial activity is due to two different bacteriocins. Amino acid sequences obtained by Edman degradation and DNA sequencing analyses revealed that one is identical to the sec-dependent pediocin-like enterocin P produced by E. faecium P13 (L. M. Cintas, P. Casaus, L. S. Håvarstein, P. E. Hernández, and I. F. Nes, Appl. Environ. Microbiol. 63:4321–4330, 1997) and the other is a novel unmodified non-pediocin-like bacteriocin termed enterocin Q (EntQ), with a molecular mass of 3,980. DNA sequencing analysis of a 963-bp region of E. faecium L50 containing the enterocin P structural gene (entP) and the putative immunity protein gene (entiP) reveals a genetic organization identical to that previously found in E. faecium P13. DNA sequencing analysis of a 1,448-bp region identified two consecutive but diverging open reading frames (ORFs) of which one, termed entQ, encodes a 34-amino-acid protein whose deduced amino acid sequence was identical to that obtained for EntQ by amino acid sequencing, showing that EntQ, similarly to EntL50A and EntL50B, is synthesized without an N-terminal leader sequence or signal peptide. The second ORF, termed orf2, was located immediately upstream of and in opposite orientation to entQ and encodes a putative immunity protein composed of 221 amino acids. Bacteriocin production by E. faecium L50 showed that EntP and EntQ are produced in the temperature range from 16 to 47°C and maximally detected at 47 and 37 to 47�

Dietary Supplementation with a Combination of Lactoferrin, Fish Oil, and Enterococcus faecium WB2000 for Treating Dry Eye: A Rat Model and Human Clinical Study.

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Kawashima, Motoko; Nakamura, Shigeru; Izuta, Yusuke; Inoue, Sachiko; Tsubota, Kazuo

2016-04-01

To examine the effect of a combined dietary supplement containing fish oil, lactoferrin, zinc, vitamin C, lutein, vitamin E, γ-aminobutanoic acid, and Enterococcus faecium WB2000 on dry eye. A preliminary study in a rat model and a prospective, randomized, double-blind, placebo-controlled study in humans were conducted. Forty Japanese volunteers aged 22 to 59 years were randomized into combined dietary supplement (2 capsules/day; 20 participants) and placebo (vehicle; 19 participants) groups and treated once daily for 8 weeks. Rats received the combined dietary supplement components (10 or 50 mg/kg orally) or vehicle (2% DMSO), and dry eye was mechanically induced for 2 days. Tear production was measured in rats after dry eye was induced. Humans were assessed at baseline and weeks 4 and 8 post-supplementation based on keratoconjunctival epithelial damage; fluorescein tear film breakup time; tear production; biochemical data; information regarding subjective dry eye symptoms by answering a questionnaire; and information regarding adverse events via medical interviews. Supplementation dose-dependently mitigated the decrease in tear production in rats. Among subjects with confirmed dry eye, clinical symptoms improved at weeks 4 and 8 more significantly in the supplementation group than in the placebo group (Peye symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative Characterization Of Endemic Lactic Acid Bacteria Of Enterococcus Genus

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Kristina Karapetyan

2017-07-01

Full Text Available The diversity of multidrug-resistance MDR of pathogenic strains to antibiotics most widely used for treatment of human diseases in the Republics of Armenia and Nagorno Karabakh were examined. It was shown that difference of resistance of pathogens to antibiotics depends on their isolation sources. It was shown that bacteriocin containing partially purified preparations obtained from different strains of Enterococcus faecium and durans species isolated from various samples of matsun salted cheese and other acid milk products from milk of different domestic animals from rural households inhibited the growth of multidrug-resistant bacteria belonging to different taxonomic groups with different efficiency.

Effect of the probiotic Enterococcus faecium SF68 on presence of diarrhea in cats and dogs housed in an animal shelter.

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Bybee, S N; Scorza, A V; Lappin, M R

2011-01-01

Beneficial effects of probiotics have never been analyzed in an animal shelter. Dogs and cats housed in an animal shelter and administered a probiotic are less likely to have diarrhea of ≥2 days duration than untreated controls. Two hundred and seventeen cats and 182 dogs. Double blinded and placebo controlled. Shelter dogs and cats were housed in 2 separate rooms for each species. For 4 weeks, animals in 1 room for each species was fed Enterococcus faecium SF68 while animals in the other room were fed a placebo. After a 1-week washout period, the treatments by room were switched and the study continued an additional 4 weeks. A standardized fecal score system was applied to feces from each animal every day by a blinded individual. Feces of animals with and without diarrhea were evaluated for enteric parasites. Data were analyzed by a generalized linear mixed model using a binomial distribution with treatment being a fixed effect and the room being a random effect. The percentage of cats with diarrhea ≥2 days was significantly lower (P = .0297) in the probiotic group (7.4%) when compared with the placebo group (20.7%). Statistical differences between groups of dogs were not detected but diarrhea was uncommon in both groups of dogs during the study. Cats fed SF68 had fewer episodes of diarrhea of ≥2 days when compared with controls suggests the probiotic may have beneficial effects on the gastrointestinal tract. Copyright © 2011 by the American College of Veterinary Internal Medicine.

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?

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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. Copyright © 2016 Elsevier B.V. All rights reserved.

La estructura resistente

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Manterola, J.

1968-09-01

Full Text Available A structure, as a whole, consists of an organised set of material parts, whose structural significance depends both on their topological nature and on the external forces acting on them. This duality, that is typical of a structure, is related on the one hand to the structural forms that man can construct, and on the other to progressive adaptation of the structural topology to the external forces acting on it. The integrated study of the constructive process and of the theory of structures does not exhaust the problem of structures. The characteristics of the materials are still to be considered. The effect of these three factors on the cost depends on the dynamic evolution of these factors themselves: their importance being greater or smaller according to the evolutionary stage that is considered and the purpose of the structure. Furthermore, the structural significance of an object is influenced by the changes in the surrounding structural elements. Thus, a form, whose development might be determined strictly by structural motives at a given period, at another stage may no longer depend on structural factors. Hence structure is only a relative concept.En la estructura resistente, tomada como un todo, subyace una organización de elementos materiales, cuyo valor de posición viene condicionado tanto por las condiciones mecánicas de trabajo resistente que se establece entre ellas como por la posibilidad de manejar y colocar en su sitio el peso y volumen que determinan. Esta partición, contenido mismo de lo estructural, nos remite, por un lado, a las condiciones variables en que se concretan las posibilidades energéticas de la humanidad, y por otro, sitúa la estructura enfrentada a las acciones exteriores en una serie de etapas intermedias que para ser resistidas va a ser construida, lo que le proporciona la operatividad que reside en todo proceso de crecimiento. La integración del proceso constructivo y la teoría de lo resistente no agota

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.

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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 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.

Susceptibility to disinfectants in antimicrobial-resistant and -susceptible isolates of Escherichia coli, Enterococcus faecalis and Enterococcus faecium from poultry-ESBL/AmpC-phenotype of E. coli is not associated with resistance to a quaternary ammonium compound, DDAC.

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Wieland, N; Boss, J; Lettmann, S; Fritz, B; Schwaiger, K; Bauer, J; Hölzel, C S

2017-06-01

The spread of bacteria that are simultaneously resistant to disinfectants and antimicrobials would constitute an unsettling scenario. In order to explore an association between antimicrobial resistance and reduced susceptibility to biocides/microbicides (disinfectants) in agriculture, we investigated Escherichia coli (n = 438) and enterococci (n = 120) isolated from six different flocks of the same poultry farm with known history of antimicrobial treatment. Susceptibility to disinfectants (formic acid and a quaternary ammonium compound (QAC), didecyldimethylammoniumchloride-DDAC) was assessed by macrodilution according to guidelines of the German Veterinary Society. Escherichia coli, Enterococcus faecalis and Enterococcus faecium were screened (i) for reduced biocide susceptibility and (ii) for an association of biocide susceptibility and antimicrobial resistance including the production of extended-spectrum beta-lactamases (ESBL) and the hyperproduction of AmpC-type beta-lactamases. DDAC inhibited ESBL/AmpC(hyper)-producing E. coli (n = 53) from poultry at similar or slightly lower inhibitory concentrations, compared with non-ESBL/AmpC strains (median MIC = 0·36 vs 1·44 mg l -1 ). In contrast, DDAC-MICs were positively correlated with several other antibiotic MICs (e.g. piperacillin and sulphamethoxazole + trimethoprim in E. coli, chloramphenicol in E. faecalis) and increased DDAC-MICs were statistically linked to high-level aminoglycoside resistance in enterococci (streptomycin high level). DDAC-MICs did not correlate with the presence of the integron marker qacEDelta1. This study provides indication that residual disinfectant might be able to select antimicrobial-resistant enterococci, but not ESBL-/AmpC (hyper)producing E. coli from poultry. While ESBL-/AmpC-E. coli were inhibited at disinfectant concentrations comparable to or lower than wildtype values, low concentrations of QACs might be able to select other antimicrobial-resistant E

The use of high-throughput sequencing to investigate an outbreak of glycopeptide-resistant Enterococcus faecium with a novel quinupristin-dalfopristin resistance mechanism.

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Shaw, Timothy D; Fairley, D J; Schneiders, T; Pathiraja, M; Hill, R L R; Werner, G; Elborn, J S; McMullan, R

2018-02-24

High-throughput sequencing (HTS) has successfully identified novel resistance genes in enterococci and determined clonal relatedness in outbreak analysis. We report the use of HTS to investigate two concurrent outbreaks of glycopeptide-resistant Enterococcus faecium (GRE) with an uncharacterised resistance mechanism to quinupristin-dalfopristin (QD). Seven QD-resistant and five QD-susceptible GRE isolates from a two-centre outbreak were studied. HTS was performed to identify genes or predicted proteins that were associated with the QD-resistant phenotype. MLST and SNP typing on HTS data was used to determine clonal relatedness. Comparative genomic analysis confirmed this GRE outbreak involved two distinct clones (ST80 and ST192). HTS confirmed the absence of known QD resistance genes, suggesting a novel mechanism was conferring resistance. Genomic analysis identified two significant genetic determinants with explanatory power for the high level of QD resistance in the ST80 QD-resistant clone: an additional 56aa leader sequence at the N-terminus of the lsaE gene and a transposon containing seven genes encoding proteins with possible drug or drug-target modification activities. However, HTS was unable to conclusively determine the QD resistance mechanism and did not reveal any genetic basis for QD resistance in the ST192 clone. This study highlights the usefulness of HTS in deciphering the degree of relatedness in two concurrent GRE outbreaks. Although HTS was able to reveal some genetic candidates for uncharacterised QD resistance, this study demonstrates the limitations of HTS as a tool for identifying putative determinants of resistance to QD.

The Leaderless Bacteriocin Enterocin K1 Is Highly Potent against Enterococcus faecium: A Study on Structure, Target Spectrum and Receptor.

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Ovchinnikov, Kirill V; Kristiansen, Per Eugen; Straume, Daniel; Jensen, Marianne S; Aleksandrzak-Piekarczyk, Tamara; Nes, Ingolf F; Diep, Dzung B

2017-01-01

Enterocin K1 (EntK1), enterocin EJ97 (EntEJ97), and LsbB are three sequence related leaderless bacteriocins. Yet LsbB kills only lactococci while EntK1 and EntEJ97 target wider spectra with EntK1 being particularly active against Enterococcus faecium , including nosocomial multidrug resistant isolates. NMR study of EntK1 showed that it had a structure very similar to LsbB - both having an amphiphilic N-terminal α-helix and an unstructured C-terminus. The α-helix in EntK1 is, however, about 3-4 residues longer than that of LsbB. Enterococcal mutants highly resistant to EntEJ97 and EntK1 were found to have mutations within rseP , a gene encoding a stress response membrane-bound Zn-dependent protease. Heterologous expression of the enterococcal rseP rendered resistant cells of Streptococcus pneumoniae sensitive to EntK1 and EntEJ97, suggesting that RseP likely serves as the receptor for EntK1 and EntEJ97. It was also shown that the conserved proteolytic active site in E. faecalis RseP is partly required for EntK1 and EntEJ97 activity, since alanine substitutions of its conserved residues (HExxH) reduced the sensitivity of the clones to the bacteriocins. RseP is known to be involved in bacterial stress response. As expected, the growth of resistant mutants with mutations within rseP was severely affected when they were exposed to higher (stressing) growth temperatures, e.g., at 45°C, at which wild type cells still grew well. These findings allow us to design a hurdle strategy with a combination of the bacteriocin(s) and higher temperature that effectively kills bacteriocin sensitive bacteria and prevents the development of resistant cells.

The Leaderless Bacteriocin Enterocin K1 Is Highly Potent against Enterococcus faecium: A Study on Structure, Target Spectrum and Receptor

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Kirill V. Ovchinnikov

2017-05-01

Full Text Available Enterocin K1 (EntK1, enterocin EJ97 (EntEJ97, and LsbB are three sequence related leaderless bacteriocins. Yet LsbB kills only lactococci while EntK1 and EntEJ97 target wider spectra with EntK1 being particularly active against Enterococcus faecium, including nosocomial multidrug resistant isolates. NMR study of EntK1 showed that it had a structure very similar to LsbB – both having an amphiphilic N-terminal α-helix and an unstructured C-terminus. The α-helix in EntK1 is, however, about 3–4 residues longer than that of LsbB. Enterococcal mutants highly resistant to EntEJ97 and EntK1 were found to have mutations within rseP, a gene encoding a stress response membrane-bound Zn-dependent protease. Heterologous expression of the enterococcal rseP rendered resistant cells of Streptococcus pneumoniae sensitive to EntK1 and EntEJ97, suggesting that RseP likely serves as the receptor for EntK1 and EntEJ97. It was also shown that the conserved proteolytic active site in E. faecalis RseP is partly required for EntK1 and EntEJ97 activity, since alanine substitutions of its conserved residues (HExxH reduced the sensitivity of the clones to the bacteriocins. RseP is known to be involved in bacterial stress response. As expected, the growth of resistant mutants with mutations within rseP was severely affected when they were exposed to higher (stressing growth temperatures, e.g., at 45°C, at which wild type cells still grew well. These findings allow us to design a hurdle strategy with a combination of the bacteriocin(s and higher temperature that effectively kills bacteriocin sensitive bacteria and prevents the development of resistant cells.

Heterologous expression of enterocin A, a bacteriocin from Enterococcus faecium, fused to a cellulose-binding domain in Escherichia coli results in a functional protein with inhibitory activity against Listeria.

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Klocke, Michael; Mundt, Kerstin; Idler, Frank; Jung, Sabrina; Backhausen, Jan E

2005-06-01

The genes for the bacteriocins enterocin A and B were isolated from Enterococcus faecium ATB 197a. Using the pET37b(+) vector, the enterocin genes were fused to an Escherichia coli specific export signal sequence, a cellulose-binding domain (CBD(cenA)) and a S-tag under the control of a T7lac promotor. The constructs were subsequently cloned into E. coli host cells. The expression of the recombinant enterocins had different effects on both the host cells and other Gram-positive bacteria. The expression of entA in Esc. coli led to the synthesis and secretion of functional active enterocin A fusion proteins, which were active against some Gram-positive indicator bacteria, but did not influence the viability of the host cells. In contrast, the expression of enterocin B fusion proteins led to a reduced viability of the host cells, indicating a misfolding of the protein or interference with the cellular metabolism of Esc. coli. Indicator strains of Gram-positive bacteria were not inhibited by purified enterocin B fusion proteins. However, recombinant enterocin B displayed inhibitory activity after the proteolytic cleavage of the fused peptides.

Avaliação de um sistema automatizado na identificação de espécies de Enterococcus Evaluation of an automated system for the identification of Enterococci

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Pedro Alves d'Azevedo

2004-08-01

Full Text Available O uso de métodos automatizados tem freqüentemente levado a falhas na identificação do gênero Enterococcus em laboratórios de microbiologia clínica. Neste estudo foi avaliada a utilização de um sistema automatizado Vitek (bioMérieux em dois laboratórios de microbiologia clínica para identificação de diferentes espécies de enterococos. Os resultados foram comparados com os testes fisiológicos convencionais. As amostras (80 foram inoculadas em testes bioquímicos convencionais e no cartão Vitek GPI. No geral, a concordância entre os dois métodos foi de 83,7% (67/80. Entre as amostras de E. faecalis, o sistema Vitek identificou corretamente 35/40 (87,5% e entre os E. faecium, a concordância foi 12/14 (85,7%. Em 20/26 amostras (76,9% pertencentes a espécies não-E. faecalis e não-E. faecium, o sistema chegou à identificação correta. Os resultados do presente estudo mostram que o sistema Vitek necessita de melhorias para a identificação de enterococos, especialmente diante de espécies menos freqüentes.Automated systems may present problems in the identification of members of the genus Enterococcus in clinical laboratories. Having conventional physiological tests as the reference method, we evaluated the use of an automated system (VITEK - bioMérieux in the identification of 80 isolates belonging to different species of Enterococcus. The general agreement between results obtained by the conventional method and by the Vitek GPI card was 83.7% (67/80. Among isolates of E. faecalis and E faecium we observed that the automated system correctly identified 35/40 (87.5% and 12/14 (85.7% of the strains, respectively. Among isolates belonging to species which are neither E. faecalis, nor E. faecium, it was observed an agreement of 20/26 (76.9%. Results point to the need of improvement in the automated systems to identify enterococci. Special consideration must be taken regarding less frequently isolated species.

Tendencias de los fenotipos de resistencia bacteriana en hospitales públicos y privados de alta complejidad de Colombia Trends of bacterial resistance phenotypes in high-complexity public and private hospitals in Colombia

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Andrea Patricia Villalobos Rodríguez

2011-12-01

Full Text Available OBJETIVO: Describir y comparar las frecuencias de los fenotipos de resistencia bacteriana de microorganismos obtenidos de pacientes en unidades de cuidados intensivos (UCI y otros servicios de hospitalización (no UCI públicos y privados de alta complejidad de Colombia. MÉTODOS: Estudio observacional, analítico, retrospectivo y multicéntrico, en el cual se consolidaronlos registros de los aislamientos bacterianos y los fenotipos de resistencia bacteriana de los microorganismos obtenidos de pacientes atendidos en UCI y no UCI de 79 hospitales públicos y privados de alta complejidad en el período de enero de 2007 a diciembre de 2009. La información se analizó con el programa WHONET® versión 5.5 (OMS de acuerdo con las recomendaciones del Instituto de Estándares Clínicos y de Laboratorio 2009 y se resumió en un formato de extracción de datos en Excel®. Se realizó un análisis descriptivo en el cual se calcularon proporciones. El análisis de tendencias se realizó mediante la prueba de correlación de rangos de Spearman. RESULTADOS: Las tendencias de los fenotipos de resistencia bacteriana de 2007 a 2009 muestran un comportamiento incremental en la proporción de Enterococcus faecium resistente a vancomicina, Klebsiella pneumoniae resistente a imipenem y a ciprofloxacina, Escherichia coli resistente a ceftazidima, y Enterobacter cloacae resistente a cefotaxima (ρ = 1, P OBJECTIVE: Describe and compare the frequency of bacterial resistance phenotypes of microorganisms obtained from patients in intensive care units (ICU and other (non-ICU high-complexity public and private hospital services in Colombia. METHODS: A retrospective observational, analytical, multicenter study was conducted. The records from January 2007 to December 2009 on bacterial isolates and bacterial resistance phenotypes of microorganisms obtained from ICU and non-ICU patients in 79 high-complexity public and private hospitals were consolidated. The information was

Antimicrobial susceptibility among Enterococcus isolates from the city of Porto Alegre, RS, Brazil Sensibilidade aos antimicrobianos entre amostras de Enterococcus isolados na cidade de Porto Alegre, RS, Brasil

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Pedro Alves d'Azevedo

2004-09-01

. faecalis (92,8%, seguidas por E. faecium (2,9%, E. gallinarum (1,5%, E. avium (1,1%, E. hirae (0,7%, E. casseliflavus (0,4%, E. durans (0,4% e E. raffinosus (0,2%. Os testes de sensibilidade revelaram que 62,0% das amostras foram resistentes à tetraciclina, 42,6% à eritromicina, 24,8% ao cloranfenicol, 22,6% à ciprofloxacina, 22,0% à norfloxacina, 3,5% à ampicilina e 3,5% á nitrofurantoína. Resistência a níveis elevados de aminoglicosídeos foi encontrada em 37,8% das amostras, com 23,5% sendo resistente à gentamicina, 14,3% à estreptomicina e 2,8% a ambos gentamicina e estreptomicina. Nenhuma amostra com resistência adquirida à vancomicina ou produtora de b-lactamase foi encontrada. Os resultados indicam um significante percentual de amostras resistentes a diferentes antimicrobianos, apontando a necessidade de estratégias de controle para evitar a disseminação de cepas resistentes e de vigilância contínua para a detecção de características emergentes de resistência.

Assessing outcomes of adult oncology patients treated with linezolid versus daptomycin for bacteremia due to vancomycin-resistant Enterococcus.

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Patel, Khilna; Kabir, Rubiya; Ahmad, Samrah; Allen, Steven L

2016-04-01

The incidence and severity of vancomycin-resistant Enterococcus blood stream infections continue to rise and is a significant burden in the healthcare setting. Literature thus far is minimal regarding treatment outcomes in patients with malignancy and vancomycin-resistant Enterococcus bacteremia. Appropriate antibiotic selection is vital to treatment success due to high rates of resistance, limited antimicrobials and mortality in this patient population. We conducted this study to determine whether treatment outcomes differed between cancer patients treated with linezolid and those treated with daptomycin for vancomycin-resistant Enterococcus bacteremia. This single-center, retrospective study included adult patients hospitalized on the oncology service with documented vancomycin-resistant Enterococcus faecium or Enterococcus faecalis bacteremia who received at least 48 h of either linezolid or daptomycin as primary treatment. A total of 65 patients were included in the analysis. Thirty-two patients received daptomycin as primary treatment, and 33 patients received linezolid as primary treatment. Twenty-six (76.5%) patients in the linezolid cohort versus 22 (71%) patients in the daptomycin cohort achieved microbiological cure (p = 0.6141). Median length of stay in days (30 vs. 42, p = 0.0714) and mortality (7/32 (20.6%) vs. 8/33 (25.8%), p = 0.6180) were also similar between the linezolid and daptomycin treated patients, respectively. No differences in microbiological cure, length of stay or mortality were identified between the groups. This study suggests that linezolid and daptomycin are each reasonable options for treating vancomycin-resistant Enterococcus bacteremia in oncology patients. Further prospective, randomized controlled trials are needed to assess the optimal treatment for vancomycin-resistant Enterococcus bacteremia in this patient population. © The Author(s) 2014.

Presence of the resistance genes vanC1 and pbp5 in phenotypically vancomycin and ampicillin susceptible Enterococcus faecalis.

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Schwaiger, Karin; Bauer, Johann; Hörmansdorfer, Stefan; Mölle, Gabriele; Preikschat, Petra; Kämpf, Peter; Bauer-Unkauf, Ilse; Bischoff, Meike; Hölzel, Christina

2012-08-01

Ampicillin and vancomycin are important antibiotics for the therapy of Enterococcus faecalis infections. The ampicillin resistance gene pbp5 is intrinsic in Enterococcus faecium. The vanC1 gene confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Both genes are chromosomally located. Resistance to ampicillin and vancomycin was determined in 484 E. faecalis of human and porcine origin by microdilution. Since E. faecalis are highly skilled to acquire resistance genes, all strains were investigated for the presence of pbp5 (and, in positive strains, for the penicillin-binding protein synthesis repressor gene psr) and vanC1 (and, in positive strains, for vanXYc and vanT) by using polymerase chain reaction (PCR). One porcine and one human isolate were phenotypically resistant to ampicillin; no strain was vancomycin resistant. Four E. faecalis (3/1 of porcine/human origin) carried pbp5 (MIC=1 mg/L), and four porcine strains were vanC1 positive (minimum inhibitory concentration [MIC]=1 mg/L). Real-time reverse transcriptase (RT)-PCR revealed that the genes were not expressed. The psr gene was absent in the four pbp5-positive strains; the vanXYc gene was absent in the four vanC1-positive strains. However, vanT of the vanC gene cluster was detected in two vanC1-positive strains. To our knowledge, this is the first report on the presence of pbp5, identical with the "E. faecium pbp5 gene," and of vanC1/vanT in E. faecalis. Even if resistance is not expressed in these strains, this study shows that E. faecalis have a strong ability to acquire resistance genes-and potentially to spread them to other bacteria. Therefore, close monitoring of this species should be continued.

Enterococcus phages as potential tool for identifying sewage inputs in the Great Lakes region

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Vijayavel, K.; Byappanahalli, Muruleedhara N.; Whitman, Richard L.; Ebdon, J.; Taylor, H.; Kashian, D.R.

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.

CLINICAL AND PHARMACOECONOMIC REASONABILITY OF USING PROBIOTIC ENTEROCOCCUS STRAIN FOR THE COMPLEX DEVELOPMENTAL CARE PROGRAM FOR PREMATURE INFANTS

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N. V. Gonchar

2015-01-01

Full Text Available Introduction. Possibilities of using probiotic enterococci in premature neonates undergoing inpatient antibacterial therapy remains understudied. The article is aimed at analyzing clinical and pharmacoeconomic reasonability of using probiotic Enterococcus faecium L3 strain in premature infants with very low body weight in the framework of complex inpatient developmental care. Patients and methods. 55 children randomized into 2 groups were observed: the control group (n = 26 was undergoing standard developmental care program, the primary group (n = 29 was introduced liquid probiotic Enterococcus faecium L3 strain (titer — 108 CFU/ml or more (0.5 ml TID for 14 days after attaining the enteral feeding volume of 5.0 ml. Results. Analysis of the clinical symptoms characteristic of non-smooth course of developmental care over premature infants helped to reveal higher frequency of infectious complications in the control group children than in the primary group (14 [53.8%] vs. 6 [20.7%]; p < 0.05. Acute food intolerance was observed less frequently in the primary group than in the control group (6 [20.7%] vs. 10 [38.5%], p > 0.05. The primary group's children featured significant decrease in the frequency of monocytosis, positive changes of intestinal microbiotic composition (increase in the amount of bifidum bacteria, lactobacilli, enterococci, decrease in the amount of Clostridium difficile and antibiotic-resistant clinical Klebsiella pneumoniae strains. Conclusion. Favorable outcome of developmental care over premature infants (absence of infectious complications was less expensive in the primary group's children.

LOS ALMIDONES RESISTENTES Y LA SALUD

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Carmen Carla Quiroga Ledezma

2009-01-01

Para una mejor comprensión de los almidones resistentes y su efecto en la salud se hizo una revisión bibliográfica de los trabajos publicados: estructura del almidón, tipos de modificaciones a la estructura del almidón, digestión del almidón, tipos de almidones, consecuencias fisiológicas del almidón resistente y tendencias futuras.

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

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Luther, Megan K.; Arvanitis, Marios; Mylonakis, Eleftherios

2014-01-01

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. PMID:24867993

Persistence of Vancomycin Resistance in Multiple Clones of Enterococcus faecium Isolated from Danish Broilers 15 Years after the Ban of Avoparcin

DEFF Research Database (Denmark)

Bortolaia, Valeria; Mander, Manuela; Jensen, Lars Bogø

2015-01-01

associated with a transferable nontypeable plasmid lineage occurring in multiple E. faecium clones. Coselection of sequence type 842 by tetracycline use only partly explained the persistence of vancomycin resistance in the absence of detectable plasmid coresistance and toxin-antitoxin systems....

Trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital: a 4-year study Evolução da resistência aos antimicrobianos entre isolados clínicos de enterococos em um hospital terciário brasileiro: um estudo de 4 anos

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Natália Conceição

2011-04-01

Full Text Available INTRODUCTION: In the past two decades members of the genus Enterococcus have emerged as important nosocomial pathogens worldwide. This study prospectively analyzed the distribution of species and trends in antimicrobial resistance among clinical isolates of enterococci in a Brazilian tertiary hospital from 2006-2009. METHODS: Enterococcal species were identified by conventional biochemical tests. The antimicrobial susceptibility profile was performed by disk diffusion in accordance with the Clinical and Laboratory Standards Institute (CLSI. A screening test for vancomycin was also performed. Minimal inhibitory concentration (MIC for vancomycin was determined using the broth dilution method. Molecular assays were used to confirm speciation and genotype of vancomycin-resistant enterococci (VRE. RESULTS: A total of 324 non-repetitive enterococcal isolates were recovered, of which 87% were E. faecalis and 10.8% E. faecium. The incidence of E. faecium per 1,000 admissions increased significantly (p 256µg/ mL and harbored vanA genes. The majority (89.5% of VRE belonged to E. faecium species, which were characteristically resistant to ampicillin and quinolones. Overall, ampicillin resistance rate increased significantly from 2.5% to 21.4% from 2006-2009. Resistance rates for gentamicin, chloramphenicol, tetracycline, and erythromycin significantly decreased over time, although they remained high. Quinolones resistance rates were high and did not change significantly over time. CONCLUSIONS: The data obtained show a significant increasing trend in the incidence of E. faecium resistant to ampicillin and vancomycin.INTRODUÇÃO: Nas últimas duas décadas, os enterococos emergiram como importantes patógenos nosocomiais no mundo inteiro. Neste estudo, foi analisada a distribuição das espécies e a evolução da resistência aos antimicrobianos entre isolados clínicos de enterococos obtidos em um hospital terciário, no período de 2006 a 2009. M�

Amylolytic Enzymes Acquired from L-Lactic Acid Producing Enterococcus faecium K-1 and Improvement of Direct Lactic Acid Production from Cassava Starch.

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Unban, Kridsada; Kanpiengjai, Apinun; Takata, Goro; Uechi, Keiko; Lee, Wen-Chien; Khanongnuch, Chartchai

2017-09-01

An amylolytic lactic acid bacterium isolate K-1 was isolated from the wastewater of a cassava starch manufacturing factory and identified as Entercoccus faecium based on 16S rRNA gene sequence analysis. An extracellular α-amylase was purified to homogeneity and the molecular weight of the purified enzyme was approximately 112 kDa with optimal pH value and temperature measured of 7.0 and 40 °C, respectively. It was stable at a pH range of 6.0-7.0, but was markedly sensitive to high temperatures and low pH conditions, even at a pH value of 5. Ba 2+ , Al 3+ , and Co 2+ activated enzyme activity. This bacterium was capable of producing 99.2% high optically pure L-lactic acid of 4.3 and 8.2 g/L under uncontrolled and controlled pH at 6.5 conditions, respectively, in the MRS broth containing 10 g/L cassava starch as the sole carbon source when cultivated at 37 °C for 48 h. A control pH condition of 6.5 improved and stabilized the yield of L-lactic acid production directly from starch even at a high concentration of starch at up to 150 g/L. This paper is the first report describing the properties of purified α-amylase from E. faecium. Additionally, pullulanase and cyclodextrinase activities were also firstly recorded from E. faecium K-1.

Description of two Enterococcus strains isolated from traditional Peruvian artisanal-produced cheeses with a bacteriocin-like inhibitory activity

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Aguilar Galvez A.

2009-01-01

Full Text Available The aim of this work was to isolate and to characterize strains of lactic acid bacteria (LAB with bacteriocin-like inhibitory activity from 27 traditional cheeses artisanal-produced obtained from different Peruvian regions. Twenty Gram+ and catalasenegative strains among 2,277 isolates exhibited bacteriocin-like inhibitory activity against Listeria monocytogenes CWBIB2232 as target strain. No change in inhibitory activity was observed after organic acid neutralization and treatment with catalase of the cell-free supernatant (CFS. The proteinic nature of the antimicrobial activity was confirmed for the twenty LAB strains by proteolytic digestion of the CFS. Two strains, CWBI-B1431 and CWBI-B1430, with the best antimicrobial activity were selected for further researches. These strains were taxonomically identified by phenotypic and genotypic analyses as Enterococcus mundtii (CWBI-B1431 and Enterococcus faecium (CWBI-B1430. The two strains were sensitive to vancomycin (MIC 2 μg.ml-1 and showed absence of haemolysis.

Estudo do perfil de susceptibilidade antimicrobiana e avaliação molecular de amostras de Enterococcus spp isoladas de pacientes hospitalizados - DOI: 10.4025/actascihealthsci.v25i1.2249 Study of drugs susceptibility and molecular samples evaluation of Enterococcus spp isolated in hospitalized patients - DOI: 10.4025/actascihealthsci.v25i1.2249

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Celso Luis Cardoso

2003-04-01

Full Text Available Neste estudo foi investigado o perfil de susceptibilidade antimicrobiana e avaliação molecular de amostras de Enterococcus spp, isoladas de urina, secreção purulenta, sangue e ferida cirúrgica de pacientes do Hospital Universitário de Maringá, estado do Paraná, no período entre 1998 e 2000. As amostras foram avaliadas quanto à susceptibilidade a drogas, tipificadas através de JB1-PCR e investigadas quanto à presença de gene Van A e Van B. Das 58 amostras, 98,3% foram classificadas como Enterococcus faecalis. Todas as amostras foram sensíveis à nitrofurantoína e vancomicina, 96,6% sensíveis à ampicilina, 32,8% foram resistentes à estreptomicina, 10,3% resistentes à gentamicina e ciprofloxacina e 6,9% resistentes a norfloxacina. Por meio do teste de CIM, para vancomicina, observou-se crescimento bacteriano até a concentração de 4μg/ml. Não foi detectada a presença de gene Van A e Van B. A amplificação por JB1-PCR proporcionou padrões de bandas com até 7 fragmentos sendo as amostras divididas em 6 grupos distintos. Não houve prevalência de algum padrão de bandeamento que denotasse a presença de um clone e não foi possível estabelecer correlação entre genótipo com resistência antimicrobiana.The aim of this study was to investigate the prevalency of Enterococcus spp, isolated from different clinical materials. The strains were evaluated for drugs susceptibility, typing by JB1-PCR and screened to the presence of Van A and Van B gene. From the 58 strains, 98.3% were classified as Enterococcus faecalis. All strains were sensible to nitrofurantoin and vancomycin, 96.6% were sensible to ampicilin, 32.8% were resistant to streptomycin, 10.3% were resistant to gentamicin and ciprofloxacin and 6.9% were resistant to norfloxacin. Using CIM test to check vancomycin susceptibility was observed bacterial growth until 4μg/ml. The presence of Van A e Van B gene was not detected. The amplification by JB1-PCR provided band

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 (ADSRRS fingerprinting).

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Nowakiewicz, Aneta; Ziółkowska, Grażyna; Trościańczyk, Aleksandra; Zięba, Przemysław; Gnat, Sebastian

2017-03-01

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. MICs of 12 antimicrobials were determined using the broth microdilution method, and epidemiological molecular analysis of strains belonging to selected species (faecalis, faecium and hirae) was performed using the ADSRRS-fingerprinting (amplification of DNA fragments surrounding rare restriction sites) method with a few modifications. The highest percentage of strains was resistant to tetracycline (73.4 %), erythromycin and tylosin (42.5 %) and rifampin (25.2 %), and a large number of strains 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 multidrug 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/multidrug resistance enterococci and the significant role of pigs as food animals in this process, it is necessary to introduce a multilevel control strategy by carrying out research on the resistance and molecular characteristics of indicator bacterial strains isolated from animals on individual farms.

Identification, antimicrobial resistance and genotypic characterization of Enterococcus spp. isolated in Porto Alegre, Brazil

Science.gov (United States)

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

Aislamiento de especies de enterococos causantes de infecciones y su sensibilidad a los antimicrobianos Isolation of enterococci species causative of infections and sensitivity to antimicrobial drugs

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C. Toledo

2004-03-01

Full Text Available Entre abril de 1999 y julio de 2000 se obtuvieron 144 aislamientos sucesivos de enterococos (uno por paciente a partir de cultivos de una variedad de sitios anatómicos. La distribución de las diferentes especies fue: 119 (82,6% Enterococcus faecalis, 11 (7,6% E. faecium y 14 (9,7% otras especies (5 E. raffinosus, 4 E. avium, 3 E. casseliflavus, 1 E. pseudoavium y 1 E. dispar, las cuales estuvieron asociadas con infecciones clínicas. Los sitios más comunes de aislamiento fueron: tracto urinario 54,9%, cavidad abdominal 12,5%, heridas quirúrgicas 12,5%, abscesos 6,9% y pie diabético 6,2%. Se detectó alto nivel de resistencia a gentamicina, estreptomicina o ambos en 48,6% de los aislamientos. Los aislamientos de E. faecium y E. raffinosus fueron significativamente más resistentes a ampicilina e imipenem que E. faecalis. Ninguna de las cepas exhibió actividad de b-lactamasa. Una cepa de E. faecium (0,7% fue resistente a vancomicina y teicoplanina (fenotipo Van A y dos cepas de E. casseliflavus (1,4% mostraron bajo nivel de resistencia a vancomicina (fenotipo Van C. Debido a estos diversos mecanismos de resistencia antimicrobiana, el tratamiento exitoso y el control de las infecciones enterocócicas con agentes antimicrobianos corrientes se hace cada vez más dificultoso.Beetween April 1, 1999 and June 30, 2000, 144 isolates of enterococci (one per patient from cultures of several anatomic sites were collected . One hundred and nineteen (82.6% E. faecalis, 11 (7.6% E. faecium and 14 (9.7% of other species (5 E. raffinosus, 4 E. avium, 3 E. casseliflavus, 1 E. pseudoavium, and 1 E. dispar were associated with clinical infections. The most common sites of isolation were: the urinary tract 54.9%, abdominal cavity 12.5%, surgical wounds 12.5%, abscesses 6.9% and diabetic foot 6.2%. High-level resistance to gentamicin or streptomycin or both was detected in 48.6% of the isolates. E. faecium and E. raffinosus were significantly more resistant than

Intestinal Microbiota Containing Barnesiella Species Cures Vancomycin-Resistant Enterococcus faecium Colonization

Science.gov (United States)

Bucci, Vanni; Caballero, Silvia; Djukovic, Ana; Toussaint, Nora C.; Equinda, Michele; Lipuma, Lauren; Ling, Lilan; Gobourne, Asia; No, Daniel; Taur, Ying; Jenq, Robert R.; van den Brink, Marcel R. M.; Xavier, Joao B.

2013-01-01

Bacteria causing infections in hospitalized patients are increasingly antibiotic resistant. Classical infection control practices are only partially effective at preventing spread of antibiotic-resistant bacteria within hospitals. Because the density of intestinal colonization by the highly antibiotic-resistant bacterium vancomycin-resistant Enterococcus (VRE) can exceed 109 organisms per gram of feces, even optimally implemented hygiene protocols often fail. Decreasing the density of intestinal colonization, therefore, represents an important approach to limit VRE transmission. We demonstrate that reintroduction of a diverse intestinal microbiota to densely VRE-colonized mice eliminates VRE from the intestinal tract. While oxygen-tolerant members of the microbiota are ineffective at eliminating VRE, administration of obligate anaerobic commensal bacteria to mice results in a billionfold reduction in the density of intestinal VRE colonization. 16S rRNA gene sequence analysis of intestinal bacterial populations isolated from mice that cleared VRE following microbiota reconstitution revealed that recolonization with a microbiota that contains Barnesiella correlates with VRE elimination. Characterization of the fecal microbiota of patients undergoing allogeneic hematopoietic stem cell transplantation demonstrated that intestinal colonization with Barnesiella confers resistance to intestinal domination and bloodstream infection with VRE. Our studies indicate that obligate anaerobic bacteria belonging to the Barnesiella genus enable clearance of intestinal VRE colonization and may provide novel approaches to prevent the spread of highly antibiotic-resistant bacteria. PMID:23319552

Immunochemical characterization of temperature-regulated production of enterocin L50 (EntL50A and EntL50B), enterocin P, and enterocin Q by Enterococcus faecium L50.

Science.gov (United States)

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

2006-12-01

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 degrees 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 degrees C, but production becomes negligible when the growth temperature is above 37 degrees C, whereas EntP and EntQ are synthesized at temperatures ranging from 16 to 47 degrees C. Maximum EntL50A and EntL50B production was detected at 25 degrees C, while EntP and EntQ are maximally produced at 37 and 47 degrees 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.

Analysis of gyrA and parC mutations in enterococci from environmental samples with reduced susceptibility to ciprofloxacin

DEFF Research Database (Denmark)

Petersen, A.; Jensen, Lars Bogø

2004-01-01

The quinolone resistance determining regions of gyrA and parC in four species of enterococci from environmental samples with reduced susceptibility to ciprofloxacin were sequenced. The nucleotide sequence variations of parC could be related to the different enterococcal species. Mutations...... in Enterococcus faecalis and Enterococcus faecium related to reduced susceptibility were identical to mutations detected in E jaecalis and E. faecium of clinical origin. A minimal inhibitory concentration of 8 mug ml(-1) to ciprofloxacin was not associated with any mutations in the gyrA and parC gene...... of Enterococcus casseliflavus and Enterococcus gallinarum. These two species may be intrinsically less susceptible to ciprofloxacin....

Drug: D04349 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available D04349 Drug Lactomin (JAN); Lactobacillus acidophilus; Biolact (TN) ... Enterococcus faecalis [TAX...:1351], Enterococcus faecium [TAX:1352], Lactobacillus acidophilus [TAX:1579], Lactobacillus bulgaricus [TAX

[Spectrum and drug sensitivity of pathogenic bacteria in children with nephrotic syndrome complicated by urinary tract infection: an analysis of 97 cases].

Science.gov (United States)

Song, Shao-Na; Zhang, Bi-Li; Wang, Wen-Hong; Zhang, Xuan

2012-09-01

To investigate the spectrum and drug sensitivity of pathogenic bacteria in children with nephrotic syndrome (NS) complicated by urinary tract infection (UTI). A retrospective analysis was performed on the spectrum and drug sensitivity of pathogenic bacteria in 97 children with NS complicated by UTI, who hospitalized from January to December, 2011. The incidence of UTI in children with NS was 36.5%. It was significantly more common in children with recurrent NS than in those with primary NS (44.0% vs 31.9%; Ppathogenic bacteria (50.5%), including Enterococcus faecium (29.4%) and Enterococcus faecalis (21.1%), followed by Gram-negative bacteria, such as Escherichia coli (15.6%) and Klebsiella pneumoniae (14.7%). Enterococcus was highly sensitive to nitrofurantoin, vacomycin and linezolid, but was highly resistant to tetracycline and moxifloxacin. More multi-resistant strains were detected in Enterococcus faecium than in Enterococcus faecalis (72% vs 17%; Pbacteria, 25% produced extended spectrum β-lactamases (ESBLs). ESBLs-producing bacteria had 100% sensitivity to imipenem, amikacin and piperacillin/tazobactam but were highly resistant to ampicillin, cefazolin and ceftriaxone. Children with recurrent NS are more susceptible to UTI than those with primary NS. Enterococcus is becoming major pathogenic bacteria for UTI in children with NS and has relatively high drug resistance, and most strains of Enterococcus faecium are multi-resistant.

Synthetic analogs of anoplin show improved antimicrobial activities

DEFF Research Database (Denmark)

Munk, Jens; Uggerhøj, Lars Erik; Poulsen, Tanja Juul

2013-01-01

We present the antimicrobial and hemolytic activities of the decapeptide anoplin and 19 analogs thereof tested against methicillin-resistant Staphylococcus aureus ATCC 33591 (MRSA), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), vancomycin-resistant Enterococcus faecium (ATCC...... that increasing the charge and/or hydrophobicity improves antimicrobial activity and increases hemolytic activity. For each strain tested, we identify at least six anoplin analogs with an improved therapeutic index compared with anoplin, the only exception being Enterococcus faecium, against which only few...

Cross-transmission of vancomycin-resistant Enterococcus in patients undergoing dialysis and kidney transplant

Directory of Open Access Journals (Sweden)

D. Fram

2010-01-01

Full Text Available The objective of this study was to investigate the occurrence of vancomycin-resistant Enterococcus (VRE cross-transmission between two patient groups (long-term dialysis and kidney transplant patients. Molecular typing, by automated ribotyping with the RiboPrinter Microbial Characterization System (Qualicon, USA, was used to analyze VRE isolates from 31 fecal samples of 320 dialysis patients and 38 fecal samples of 280 kidney transplant patients. Clonal spread of E. faecalis and E. casseliflavus was observed intragroup, but not between the two groups of patients. In turn, transmission of E. gallinarum and E. faecium between the groups was suggested by the finding of vancomycin-resistant isolates belonging to the same ribogroup in both dialysis and transplant patients. The fact that these patients were colonized by VRE from the same ribogroup in the same health care facility provides evidence for cross-transmission and supports the adoption of stringent infection control measures to prevent dissemination of these bacteria.

Vancomycineresistente enterokokken in Nederland

NARCIS (Netherlands)

Leavis, H. L.; Willems, R. J.; Mascini, E. M.; Vandenbroucke-Grauls, C. M.; Bonten, M. J.

2004-01-01

Enterococci (Enterococcus faecalis and Enterococcus faecium) are relatively avirulent enteric bacteria that usually only cause infections in immunocompromised patients. Antimicrobial treatment, however, is hampered as enterococci are intrinsically resistant to many antibiotics. For years, vancomycin

Multidrug-Resistant Enterococcal Infections : New Compounds, Novel Antimicrobial Therapies?

NARCIS (Netherlands)

van Harten, Roel M; Willems, Rob J L; Martin, Nathaniel I; Hendrickx, Antoni P A

Over the past two decades infections due to antibiotic-resistant bacteria have escalated world-wide, affecting patient morbidity, mortality, and health care costs. Among these bacteria, Enterococcus faecium and Enterococcus faecalis represent opportunistic nosocomial pathogens that cause

Species distribution and resistance patterns to growth-promoting antimicrobials of enterococci isolated from pigs and chickens in Korea.

Science.gov (United States)

Hwang, In Yeong; Ku, Hyun Ok; Lim, Suk Kyung; Park, Choi Kyu; Jung, Gab Su; Jung, Suk Chan; Nam, Hyang Mi

2009-11-01

A total of 147 Enterococcus faecium and 165 Enterococcus faecalis isolates from fecal samples of chickens and pigs at slaughterhouses in Korea were tested for their resistance to 8 growth-promoting antimicrobials commonly used in animals and quinupristin and dalfopristin. Resistance to most antimicrobials was very common among both E. faecalis and E. faecium. In particular, E. faecalis showed almost no susceptibility to all the antimicrobials tested except penicillin and flavomycin, to which 1.4% and less than 24% showed resistance, respectively. Although the prevalence of resistance was lower than in E. faecalis, E. faecium showed relatively uniform resistance to all the agents tested. Among the antimicrobials tested, virginiamycin and penicillin were the most effective against E. faecium isolates: less than 31% and 41% showed resistance to those 2 antimicrobials, respectively. Penicillin was the only agent that showed relatively strong activity against both E. faecalis and E. faecium. Resistance observed in E. faecalis and E. faecium against most antimicrobials used for growth promotion was more prevalent in Korea than in European countries. The current study is the first report of resistance against feed additive antimicrobials in enterococcal isolates from livestock in Korea.

SOJA IAC/IAS-5: CULTIVAR RESISTENTE AO CANCRO DA HASTE

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MASCARENHAS HIPÓLITO ASSUNÇÃO ANTONIO

1998-01-01

Full Text Available Há aproximadamente oito anos, o cancro da haste (Phomopsis phaseoli f. sp. meridionalis/Diaporthe phaseolorum f. sp. meridionalis da soja tem sido o principal fator limitante da produtividade em áreas de manifestação da doença. O seu controle mediante cultivares resistentes é o método mais econômico. Num ensaio em casa de vegetação, visando avaliar o efeito de doses de potássio no controle do cancro da haste, no cultivar IAS-5, moderadamente resistente, verificou-se haver plantas altamente resistentes, comprovadas em três gerações, todas inoculadas com o fungo causador da doença. A importância da obtenção do IAS-5 e de sua multiplicação deve-se a ser o mais cultivado no Estado de São Paulo e apresentar resistência ao cancro da haste.

Ocorrência de fungos filamentosos termo-resistentes em polpa de tomate envasada assepticamente

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BAGLIONI Flávio

1999-01-01

Full Text Available Este trabalho teve como objetivo principal determinar a ocorrência de fungos filamentosos termo-resistentes durante o processamento asséptico de polpa de tomate (8° BRIX. Durante o período de safra de tomate foram feitas amostragens em 9 lotes (3 no início, 3 no pico e 3 em fim de safra e no período de entresafra em 5 lotes. Foi feita a enumeração de fungos termo-resistentes nas amostras coletadas durante as diferentes etapas do processo asséptico de cada lote. Foram obtidas contagens médias relativamente baixas, variando entre <1 e 8UFC/100mL de amostra. As maiores contagens foram obtidas na matéria prima e na água de pré lavagem e transporte. Cinqüenta linhagens de fungos termo-resistentes detectadas no procedimento de enumeração foram isoladas, codificadas e estocadas. Os esporos de cada isolado com 1 mês de cultivo foram submetidos a diferentes choques térmicos para selecionar a linhagem de fungo mais termo-resistente. O isolado de fungo mais termo-resistente (sobrevivência ao choque à 100° C/25 minutos foi identificado como Neosartorya fischeri.

Growth interactions and antilisterial effects of the bacteriocinogenic Lactococcus lactis subsp. cremoris M104 and Enterococcus faecium KE82 strains in thermized milk in the presence or absence of a commercial starter culture.

Science.gov (United States)

Lianou, Alexandra; Kakouri, Athanasia; Pappa, Eleni C; Samelis, John

2017-06-01

Traditional Greek cheeses are often produced from thermized milk (TM) with the use of commercial starter cultures (CSCs), which may not inhibit growth of Listeria monocytogenes completely. Therefore, this study evaluated the behavior of an artificial L. monocytogenes contamination in commercially TM (63 °C; 30 s) inoculated with a CSC plus Lactococcus lactis subsp. lactis M104 and/or Enterococcus faecium KE82, two indigenous strains producing nisin A and enterocin A and B, respectively. Inoculation treatments included TM with the CSC only, and TM without the CSC but with strain M104 alone, or combined with strain KE82. All treatments were incubated at 37 °C for 6 h followed by 66 h at 18 °C. L. monocytogenes grew by 0.66-1.24 log cfu/ml at 37 °C, whereas its further growth at 18 °C was retarded, suppressed, or accompanied by different inactivation rates, depending on each TM treatment. Strain M104 caused the greatest inactivation, whereas the CSC per se was the least effective treatment. Strain KE82 assisted the CSC in controlling pathogen growth at 37 °C, whereas both reduced the nisin A-mediated antilisterial activity of strain M104. Overall, the most 'balanced' treatment against L. monocytogenes was CSC+M104+KE82. Hence, this starter/co-starter combination may be utilized in traditional Greek cheese technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Caracterização de Enterococcus spp. resistentes isolados de águas não tratadas destinadas ao consumo humano

OpenAIRE

Macedo, Ana Sofia

2011-01-01

Trabalho apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas. A água não tratada é constantemente desvalorizada como fonte de resistências a antibióticos em países desenvolvidos. Para averiguar este problema de saúde pública, neste trabalho isolaram-se Enterococcus spp. como bactérias indicadoras de contaminação fecal de poços, fontes e minas que fornecem água a diversas comunidades em Portugal e caracterizou-se o s...

Antimicrobial activity of surfactants produced by Bacillus subtilis R14 against multidrug-resistant bacteria Atividade antimicrobiana de surfactantes produzidos por Bacillus subtilis R14 frente a bacterias multidroga-resistentes

Directory of Open Access Journals (Sweden)

Paulo André Vicente Fernandes

2007-12-01

14, frente a bactérias multidroga-resistentes. Durante o cultivo em meio quimicamente definido, a tensão superficial do meio foi reduzida de 54 mN/m no início do crescimento microbiano para 30 mN/m depois de 20 h. Uma concentração de surfactante bruto de 2 g/L foi obtida depois de 40h de cultivo. Uma caracterização preliminar sugeriu que dois surfactantes foram produzidos. A avaliação antimicrobiana destes compostos foi realizada frente a vinte e nove bactérias. O perfil de multidroga-resistência foi previamente definido para Enterococcus faecalis (11 cepas Staphylococcus aureus (6 cepas, Pseudomonas aeruginosa (7 cepas e Escherichia coli IC18. Todas as cepas foram sensíveis aos surfactantes, em particular Enterococcus faecalis. Os resultados demonstraram que os lipopeptídios têm um amplo espectro de ação, incluindo microrganismos multidroga-resistentes.

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

Science.gov (United States)

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. Copyright © 2017 Elsevier B.V. All rights reserved.

Sorption of streptococcus faecium to glass

International Nuclear Information System (INIS)

Oerstavik, D.

1977-01-01

A method has been developed by which to study the sorption of Streptococcus faecium to soda-lime cover glasses. Conditions were chosen to minimize the influence on sorption of bacterial polymer production, passive sorption being studied rather than attachment mediated by metabolic activities. Sorption of S. faecium increased with increasing temperature (to 50degC), time, and cell concentration, but equilibrium apparently was not reached even after incubation for 8 hours or at a cell concentration of 3 x 10 10 per ml. Sorption increased with solute molarity up to 0.1 M concentration of NaCl and KCl, indicating an effect of the electrical double layers on the apposition of cells to the glass surface. Desorption of bacteria could be obtained after multiple washings of the glasses in buffer or by the action of Tween 80, but not if sorbed bacteria were left in distilled water, various salt solutions, urea, or in suspensions of unlabelled bacteria. It was concluded that sorption occurred as a result of chemical interactions between the glass and the cell surface. Tween 80 at a concentration of 1 per cent inhibited sorption to 26 per cent of buffer controls, 2 M urea was less effective, and 1 M NaCl was without effect. It is suggested that hydrophobic interactions may be of importance in the binding of S. faecium to glass. (author)

Eindrapportage onderzoek naar ontwikkeling Verticillium resistente Acer

NARCIS (Netherlands)

Hiemstra, J.A.; Sluis, van der B.J.

2013-01-01

Dit project is de laatste fase in het onderzoek naar de ontwikkeling van Verticillium-resistente Acer platanoides (Noorse esdoorn) onderstammen wat in 1993 van start ging op het toenmalige CPRO-DLO (nu PRI) met grootschalige selectie-experimenten. PPO-Bomen heeft vanaf 1999 onderzoek gedaan naar

Growth Behavior of E. coli, Enterococcus and Staphylococcus Species in the Presence and Absence of Sub-inhibitory Antibiotic Concentrations: Consequences for Interpretation of Culture-Based Data.

Science.gov (United States)

Heß, Stefanie; Gallert, Claudia

2016-11-01

Culture-based approaches are used to monitor, e.g., drinking water or bathing water quality and to investigate species diversity and antibiotic resistance levels in environmental samples. For health risk assessment, it is important to know whether the growing cultures display the actual abundance of, e.g., clinically relevant antibiotic resistance phenotypes such as vancomycin-resistant Enterococcus faecium/Enterococcus faecalis (VRE) or methicillin-resistant Staphylococcus aureus. In addition, it is important to know whether sub-inhibitory antibiotic concentrations, which are present in surface waters, favor the growth of antibiotic-resistant strains. Therefore, clinically relevant bacteria were isolated from different water sources and the growth behavior of 58 Escherichia coli, 71 Enterococcus, and 120 Staphylococcus isolates, belonging to different species and revealing different antibiotic resistance patterns, was studied with respect to "environmental" antibiotic concentrations. The finding that VRE could only be detected after specific enrichment can be explained by their slow growth compared to non-resistant strains. Interpreting their absence in standardized culture-based methods as nonexistent might be a fallacy. Sub-inhibitory antibiotic concentrations that were detected in sewage and receiving river water did not specifically promote antibiotic-resistant strains. Generally, those antibiotics that influenced cell metabolism directly led to slightly reduced growth rates and less than maximal optical densities after 48 h of incubation.

Adesida et al., Afr., J. Infect. Dis.

African Journals Online (AJOL)

In Nigeria, most studies on enterococci have been conducted on food, ... based on Gram stain, cultural characteristics and various biochemical tests .... Fluoroquinolones have been the preferred antibiotics for treatment of ... Clonal Diversity in Multi ... Comparison of Enterococcus faecium and Enterococcus faecalis Strains ...

Evaluation of a Chromogenic Agar under Development To Screen for VRE Colonization ▿

OpenAIRE

Kallstrom, George; Doern, Christopher D.; Dunne, W. Michael

2010-01-01

BBL CHROMagar VanRE (CVRE) was compared with bile esculin azide agar plus vancomycin to screen for vancomycin-resistant enterococcus (VRE) colonization. CVRE distinguishes Enterococcus faecalis (green colonies) from Enterococcus faecium (mauve colonies) on the basis of chromogenic substrate use. CVRE sensitivity and specificity were 98.6% and 99.1%. Positive and negative predictive values were 95.9% and 99.7%.

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.

Science.gov (United States)

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

Perfil Sazonal dos Enterococcus e E. coli nos mananciais do Distrito Federal - doi: 10.5102/ucs.v5i1.417

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Ana Flavia Correia Heringer

2008-11-01

Full Text Available Para avaliar a eficácia de um indicador microbiológico não basta verificar sua ação como fato isolado. O ambiente externo tem seu papel designado de acordo com as variações climáticas. No Distrito Federal duas estações são aparentes: o período da seca e da chuva. O objetivo deste trabalho é analisar os valores obtidos aplicando-se as técnicas do substrato enzimático para E. coli e dos tubos múltiplos para Enterococcus, comparando-os para se obter aquele que apresenta-se como melhor indicador de contaminação e determinar a influência do clima sobre a população de bactérias presentes nos mananciais. Valores demonstraram que os Enterococcus foram tão ou mais resistentes à ação do meio externo que a E. coli, embora não se possa concluir que exista um indicador mais eficaz. A avaliação sazonal determina quando podemos utilizar os indicadores devido às adversidades do meio conferindo mais segurança para a qualidade da água e, conseqüentemente, a saúde humana.

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

DEFF Research Database (Denmark)

Galimand, Marc; Schmitt, Emmanuelle; Panvert, Michel

2011-01-01

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 (m(5)C) methyltransferase modifying 16S rRNA nucleotide C1407. The target for EfmM is shown by mass spectrometry to be a neighboring 16S r...

Case report

African Journals Online (AJOL)

abp

2014-01-23

Jan 23, 2014 ... Linezolid is the only member of synthetic oxyzolidone family and is active in-vitro against resistant Gram positive cocci such as vancomycin resistant Enterococcus faecalis and Enterococcus faecium and methicilin resistant Staphylococcus aureus [9,10]. The approval was declared in our country in 2005.

Tecidos moles (não resistentes: como se fossilizam?

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Silvia Regina Gobbo

2015-06-01

Full Text Available A preservação de tecidos moles (não resistentes desperta atenção pela qualidade dos fósseis preservados, e pela raridade. Este trabalho faz ampla revisão do assunto, desfaz alguns dos mitos correntes sobre fossilização destes materiais, como anaerobiose e soterramento rápido, bem como assinala a relevância do papel da replicagem de estruturas morfológicas por colônias microbianas. No âmbito dos fatores que influenciam a preservação de tecidos não resistentes estão pH, processos de decomposição, soterramento rápido e mineralização rápida por meio de carbonatos ou fosfatos. É possível citar exemplos de fácies sedimentares nas quais há preservação de tecidos não resistentes, como os folhelhos pirobetuminosos, calcários litográficos, folhelhos e diatomitos. Destaca-se o papel das colônias microbianas, tanto na forma de microesferas, como aquelas não-esferulíticas. Os três mitos principais que se procurou desfazer no artigo são: (1 a presença de oxigênio; (2 o soterramento rápido e (3 as colônias microbianas.

Resistencia a antimicrobianos y evaluación del tratamiento combinado en la septicemia neonatal Resistance to antimicrobials and combination therapy assessment in neonatal sepsis

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María Espino Hernández

2003-04-01

Full Text Available OBJETIVOS: Estudiar la resistencia a los antibióticos de las cepas bacterianas aisladas de pacientes con septicemia neonatal en un hospital ginecobstétrico de La Habana, Cuba, en el período comprendido entre enero de 1994 y diciembre de 1998, y evaluar el valor predictivo del método del "tablero de damas" (checkerboard para seleccionar el tratamiento con combinaciones de antibióticos en pacientes graves. MÉTODOS: Se estudió a 229 neonatos, a quienes se les extrajo sangre para hemocultivo y estudios de sensibilidad a antimicrobianos. El estudio de la susceptibilidad de las cepas se realizó por el método de microdilución en caldo y se utilizó el tablero de damas en bandejas de caldo para evaluar la eficacia del tratamiento antimicrobiano combinado. RESULTADOS: Cincuenta por ciento de las cepas aisladas de Staphylococcus spp. coagulasa-negativas y 37% de las cepas de S. aureus, principales agentes causales de sepsis neonatal, fueron resistentes a la meticilina. De ellas, 94,5% resultaron resistentes a varios antibióticos. Cuatro cepas de Staphylococcus spp. coagulasa-negativas y una de Enterococcus faecium fueron resistentes a la vancomicina (concentración mínima inhibidora = 128 myg/mL. Se observó una alta probabilidad de eficacia clínica (P OBJECTIVES: To estimate antibiotic resistance among bacterial strains isolated from patients with neonatal sepsis from January 1994 through December 1998, and to assess the predictive value of the checkerboard method for selecting treatment with combination antibiotic therapy in seriously ill patients. METHODS: The study of strain susceptibility was carried out by microdilution in broth, and the checkerboard method in broth trays was used to assess the efficacy of antibiotic combination therapy. RESULTS: Fifty per cent of the strains of coagulase-negative Staphylococcus spp. and 37% of S. aureus strains, which are the main pathogens involved in neonatal sepsis, were resistant to methycillin. Of

Screening and selection of wild strains for L-arabinose isomerase production

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R. M. Manzo

2013-12-01

Full Text Available The majority of L-arabinose isomerases have been isolated by recombinant techniques, but this methodology implies a reduced technological application. For this reason, 29 bacterial strains, some of them previously characterized as L-arabinose isomerase producers, were assayed as L-arabinose fermenting strains by employing conveniently designed culture media with 0.5% (w/v L-arabinose as main carbon source. From all evaluated bacterial strains, Enterococcus faecium DBFIQ ID: E36, Enterococcus faecium DBFIQ ID: ETW4 and Pediococcus acidilactici ATCC ID: 8042 were, in this order, the best L-arabinose fermenting strains. Afterwards, to assay L-arabinose metabolization and L-arabinose isomerase activity, cell-free extract and saline precipitated cell-free extract of the three bacterial cultures were obtained and the production of ketoses was determined by the cysteine carbazole sulfuric acid method. Results showed that the greater the L-arabinose metabolization ability, the higher the enzymatic activity achieved, so Enterococcus faecium DBFIQ ID: E36 was selected to continue with production, purification and characterization studies. This work thus describes a simple microbiological method for the selection of L-arabinose fermenting bacteria for the potential production of the enzyme L-arabinose isomerase.

Harmonization of antimicrobial susceptibility testing among veterinary diagnostic laboratories in the five Nordic countries

DEFF Research Database (Denmark)

Petersen, A.; Aarestrup, Frank Møller; Hofshagen, Merete

2003-01-01

A total of 100 bacterial strains (25 Escherichia coli, 25 Salmonella enterica, 25 Staphylococcus aureus, and 25 Enterococcus strains) and four reference strains were tested for susceptibility toward 8-12 antimicrobial agents in 12 veterinary diagnostic laboratories in the five Nordic countries...... reported as vancomycin resistant. Ten laboratories identified the Enterococcus spp. to species level. All five Enterococcus faecium and 10 Enterococcus faecalis selected from the strain collection at the Danish Veterinary Institute were correctly identified by all laboratories, whereas some problems were...

Lactobacillus rhamnosus GG (ATCC 53103) and platelet aggregation in vitro.

Science.gov (United States)

Korpela, R; Moilanen, E; Saxelin, M; Vapaatalo, H

1997-06-17

Lactobacillus rhamnosus GG is an experimentally and clinically well documented probiotic used in different dairy products. The present study aimed to investigate the safety aspects of Lactobacillus rhamnosus GG, particularly with respect to platelet aggregation, the initiating event in thrombosis. Platelet rich plasma was separated from the blood of healthy volunteers, and the effects of Lactobacillus rhamnosus GG (ATCC 53103), Lactobacillus rhamnosus (ATCC 7469) and Enterococcus faecium T2L6 in different dilutions on spontaneous, ADP- and adrenaline-induced aggregation were tested. The bacteria did not influence spontaneous aggregation. Only Enterococcus faecium T2L6 enhanced the adrenaline-induced aggregation, with a less clear effect on ADP-induced aggregation.

Serum Vancomycin Levels Resulting from Continuous or Intermittent Infusion in Critically Ill Burn Patients With or Without Continuous Renal Replacement Therapy

Science.gov (United States)

2012-12-01

one (0.9%) was Streptococcus mutans , and one (0.9%) was an unidentified Enterococcus species. Organisms having MIC ≥ 2 μg/mL (as measured by the...coagulase-negative Staphylo- coccus, 13 (12.3%) were Enterococcus faecium, five (4.7%) were Enterococcus faecalis, four (3.8%) were Streptococcus ...pneumoniae, two (1.9%) were Strepto- coccus viridans, two (1.9%) were Streptococcus aga- lactiae, two (1.9%) were nonenterococcal Group D Streptococci

Vancomycin-resistant enterococci with vanA gene in treated municipal wastewater and their association with human hospital strains.

Science.gov (United States)

Oravcova, Veronika; Mihalcin, Matus; Zakova, Jana; Pospisilova, Lucie; Masarikova, Martina; Literak, Ivan

2017-12-31

Vancomycin-resistant enterococci (VRE) are pathogens of increasing medical importance. In Brno, Czech Republic, we collected 37 samples from the effluent of a wastewater treatment plant (WWTP), 21 surface swabs from hospital settings, and 59 fecal samples from hospitalized patients and staff. Moreover, we collected 284 gull cloacal swabs from the colony situated 35km downstream the WWTP. Samples were cultured selectively. Enterococci were identified using MALDI-TOF MS, phenotypically tested for susceptibility to antibiotics, and by PCR for occurrence of resistance and virulence genes. Pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were used to examine genotypic diversity. VRE carrying the vanA gene were found in 32 (86%, n=37) wastewater samples, from which we obtained 49 isolates: Enterococcus faecium (44) and Enterococcus gallinarum (2), Enterococcus casseliflavus (2), and Enterococcus raffinosus (1). From 33 (69%) of 48 inpatient stool samples, we obtained 39 vanA-carrying VRE, which belonged to E. faecium (33 isolates), Enterococcus faecalis (4), and Enterococcus raffinosus (2). Nearly one-third of the samples from hospital surfaces contained VRE with the vanA gene. VRE were not detected among gulls. Sixty-seven (84%, n=80) E. faecium isolates carried virulence genes hyl and/or esp. Virulence of E. faecalis was encoded by gelE, asa1, and cylA genes. A majority of the E. faecium isolates belonged to the clinically important sequence types ST17 (WWTP: 10 isolates; hospital: 4 isolates), ST18 (9;8), and ST78 (5;0). The remaining isolates belonged to ST555 (2;0), ST262 (1;6), ST273 (3;0), ST275 (1;0), ST549 (2;0), ST19 (0;1), ST323 (3;0), and ST884 (7;17). Clinically important enterococci carrying the vanA gene were almost continually detectable in the effluent of the WWTP, indicating insufficient removal of VRE during wastewater treatment and permanent shedding of these antibiotic resistant pathogens into the environment from this

Staphylococcus aureus Meticilina Resistente (MRSA e Infecções Nosocomiais

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CRISTINA PAIVA SOUSA

2009-12-01

Full Text Available Um número crescente de cepas de Staphylococcus aureus meticilina resistente (MRSA apresentam resistência a múltiplos agentes antimicrobianos e são implicadas como causas de infecções hospitalares. S. aureus podem ser isolados de ambiente hospitalar e profissionais da saúde, revelando o risco de transmissão desses microrganismos pelo contato direto ou indireto com pacientes hospitalizados. Objetivou-se nesta revisão correlacionar este microrganismo com infecções hospitalares e avaliar as possíveis fontes de infecção, bem como enfatizar a importância do investimento em ações de educação em saúde que culminem em minimização de infecções hospitalares. Palavras-chave: Staphylococcus aureus meticilina resistente. Infecções nosocomiais.

Biodiversity of lactic acid bacteria in Moroccan soft white cheese (Jben).

Science.gov (United States)

Ouadghiri, Mouna; Amar, Mohamed; Vancanneyt, Marc; Swings, Jean

2005-10-15

The bacterial diversity occurring in traditional Moroccan soft white cheese, produced in eight different regions in Morocco, was studied. A total of 164 lactic acid bacteria were isolated, purified and identified by whole-cell protein fingerprinting and rep-PCR genomic fingerprinting. The majority of the strains belonged to the genera Lactobacillus, Lactococcus, Leuconostoc and Enterococcus. Sixteen species were identified: Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus paracasei, Lactobacillus brevis, Lactobacillus buchneri, Lactococcus lactis, Lactococcus garvieae, Lactococcus raffinolactis, Leuconostoc pseudomesenteroides, Leuconostoc mesenteroides, Leuconostoc citreum, Eterococcus durans, Enterococcus faecalis, Enterococcus faecium, Enterococcus saccharominimus and Streptococcus sp.

Both live and dead Enterococci activate Caenorhabditis elegans host defense via immune and stress pathways.

Science.gov (United States)

Yuen, Grace J; Ausubel, Frederick M

2018-12-31

The innate immune response of the nematode Caenorhabditis elegans has been extensively studied and a variety of Toll-independent immune response pathways have been identified. Surprisingly little, however, is known about how pathogens activate the C. elegans immune response. Enterococcus faecalis and Enterococcus faecium are closely related enterococcal species that exhibit significantly different levels of virulence in C. elegans infection models. Previous work has shown that activation of the C. elegans immune response by Pseudomonas aeruginosa involves P. aeruginosa-mediated host damage. Through ultrastructural imaging, we report that infection with either E. faecalis or E. faecium causes the worm intestine to become distended with proliferating bacteria in the absence of extensive morphological changes and apparent physical damage. Genetic analysis, whole-genome transcriptional profiling, and multiplexed gene expression analysis demonstrate that both enterococcal species, whether live or dead, induce a rapid and similar transcriptional defense response dependent upon previously described immune signaling pathways. The host response to E. faecium shows a stricter dependence upon stress response signaling pathways than the response to E. faecalis. Unexpectedly, we find that E. faecium is a C. elegans pathogen and that an active wild-type host defense response is required to keep an E. faecium infection at bay. These results provide new insights into the mechanisms underlying the C. elegans immune response to pathogen infection.

Dominant lactic acid bacteria in artisanal Pirot cheeses of different ripening period

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Terzić-Vidojević Amarela

2009-01-01

Full Text Available In this study two raw cow's milk cheeses of a different ripening period were examined. The cheeses were taken from a country household in the region of mountain Stara Planina and manufactured without adding of starter culture. A total 106 lactic acid bacteria (LAB strains were isolated from both cheeses. They are tested by classical physiological tests as well as by API 50 CH tests. Proteolytic and antimicrobial activities were done too. Identification of LAB isolates was done by repetitive extragenic palindromic-polimerase chain reaction (rep-PCR with (GTG5 primer. The LAB isolates from cheese BGPT9 (four days old belonged to the eight species of LAB (Lactobacillus plantarum, Lactobacillus paracasei subsp. paracasei, Lactobacillus delbrueckii, Lactobacillus brevis, Enterococcus faecium, Enterococcus faecalis, Enterococcus durans and Leuconostoc garlicum, while in the BGPT10 cheese (eight months old only two species were present (Lactobacillus plantarum and Enterococcus faecium. Proteolytic activity showed 30 LAB from BGPT9 cheese, mainly enterococci. From BGPT10 cheese only one isolate (which belonged to the Lactobacillus plantarum species possessed partial ability to hydrolyze β-casein. Seven enterococci from BGPT9 cheese and four enterococci from BGPT10 cheese produced antimicrobial compounds.

OCORRÊNCIA E CARACTERIZAÇÃO DO AMIDO RESISTENTE EM AMIDOS DE MILHO E DE BANANA

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Teixeira Maria A.V.

1998-01-01

Full Text Available No presente trabalho foi estudada a ocorrência de Amido Resistente (AR em amidos de milho e de banana (naturalmente resistente e investigado o efeito das variáveis: umidade de condicionamento, tempo e temperatura de armazenamento dos géis, na formação do AR em amido normal de milho; além das características físico-químicas e a estrutura fina do AR de milho e de banana. Foi observado que o teor de AR em amidos de milho e banana (2,5% e 49,61%, respectivamente parece não estar relacionada com a composição química do grânulo. O amido de banana apresentou grânulos com certo poliformismo, padrão de raio-x tipo B, além de uma fração linear de DP 34 resistente à b-amilólise. A estrutura cristalina que mantém o grânulo do amido de banana coeso, por si só, não explicou o alto teor de AR encontrado. O amido de milho normal apresentou formas poliédricas e padrão difração em raio-x tipo A. Não foi observada a fração com DP 34 resistente à b-amilólise, apesar da sua maior coesividade quando comparado ao amido de banana. O tratamento hidrotérmico aplicado no amido normal de milho quase triplicou o teor de AR (7,15% devido à formação de estruturas cristalinas coesas. O AR de milho (7,15% de AR, constituído por fragmentos porosos, apresentou padrão de difração tipo C. A não significância do tempo de armazenamento dos géis na produção do AR e a fração linear com DP 34 resistente à b-amilólise presente nos cromatogramas, sugerem a participação da amilose na formação desta estrutura resistente.

Susceptibility of Escherichia coli and Enterococcus faecium isolated from pigs and broiler chickens to tetracycline degradation products and distribution of tetracycline resistance determinants in E-coli from food animals

DEFF Research Database (Denmark)

Sengeløv, G.; Halling-Sørensen, B.; Aarestrup, Frank Møller

2003-01-01

of tet(A) and tet(B) applied to all three animal species, and there was no difference between the distribution of tet(A) and tet(B) genes among non-pathogenic and pathogenic E. coli in any of the animal species. The susceptibility of 20 of these isolates together with 10 tetracycline sensitive E. coli......-anhydrochlortetracycline. In general both the tetracycline resistant and susceptible E. faecium were more susceptible to the compounds tested than E. coli. (C) 2003 Elsevier B.V.. All rights reserved....

Use of a high resolution melt real-time polymerase chain reaction (PCR) assay for the environmental monitoring of Vibrio cholerae

CSIR Research Space (South Africa)

Le Rouw, Wouter J

2011-10-01

Full Text Available ATCC 9207 Shigella sonnei ATCC 9290 Enterococcus faecium ATCC 6569 Enterobacter aerogenes ATCC 13048 Klebsiella pneumoniae Vermaak and Partners Pathologists, S.A. Pseudomonas aeruginosa ATCC 27853 Staphylococcus aureus ATCC 25923 Proteus...

Characterization of non-starter lactic acid bacteria in traditionally produced home-made Radan cheese during ripening

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Jokovic Natasa

2011-01-01

Full Text Available Two hundred thirteen non-starter lactic acid bacteria isolated from Radan cheese during ripening were identified with both a classical biochemical test and rep-PCR with (GTG5 primer. For most isolates, which belong to the Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus paraplantarum and Enterococcus faecium, a phenotypic identification was in good agreement with rep-PCR identification. Lactococeus lactis subsp. lactis, Enterococcus faecium and subspecies from the Lenconostoc mesenteroides group were the dominant population of lactic acid bacteria in cheese until 10 days of ripening and only one Streptococcus thermophilus strain was isolated from the 5-day-old cheese sample. As ripening progressed, Lactobacillus plantarum became the predominant species together with the group of heterofermentative species of lactobacilli that could not be precisely identified with rep-PCR.

Genotipos de frijol (Phaseolus Vulgaris l. resistentes a Xanthomonas campestris pv. phaseoli de Mexico

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Rosa Navarrete

2000-01-01

Full Text Available Genotipos de frijol (Phaseolus vulgaris L. resistentes a Xanthomonas campestris pv. phaseoli de México. Durante 1995 se evaluó la reacción de genotipos de frijol de diversos origenes a Xcp, bajo condiciones de invernadero en el Campo Experimental del Valle de México, del INIFAP. Se realizaron tres experimentos con a120, b44 y csiete genotipos de frijol. Las plantas se inocularon por corte con navajas en la etapa V3, a y b con una mezcla de nueve cepas de Xcp y el c, con cada una de siete cepas con diferente grado de patogenicidad. La severidad se evaluó 20 días después de la inoculación, por comparación con una escala visual de nueve grados. Los datos se analizaron bajo un diseño completamente al azar. En a, los genotipos que mostraron reacción de resistencia a Xcp fueron: A 36, A 475, G 5686, G 11867, Harowood, SEA 14, XAN 266, MCD 4012 y REN 27. En b los genotipos resistentes fueron: Sequía Durango, Taylor y XAN 30. En los experimentos anteriores la severidad de la enfermedad mostró una distribución normal, con el máximo número de genotipos en el grado de severidad cinco en a y seis en b. Los resultados obtenidos indican que el uso de mezclas de cepas de bacterias con diferente patogenicidad es eficiente para identificar genotipos de frijol resistentes a Xcp. Los genotipos resistentes identificados en el último experimento, mostraron respuesta diferencial e interacciones genotipo por cepa. REN 27 y SEA 14 mostraron resistencia a las cepas utilizadas

Mengen Peynirinden Laktik Asit Bakterilerinin İzolasyonu, Moleküler Tanımlanması ve Bazı Starter Kültür Özelliklerinin Belirlenmesi

Directory of Open Access Journals (Sweden)

Aylin AKOĞLU

2016-12-01

Full Text Available Çalışmada 50 adet Mengen peyniri örneğinden toplam 117 adet laktik asit bakterisi izole edilmiş ve laktik asit bakteri florası % 44.5 Enterococcus spp., % 29.9 Lactobacillus spp., % 25.6 Lactococcus spp. olarak belirlenmiştir. Elde edilen izolatların asidifikasyon kapasiteleri ile proteolitik aktiviteleri tespit edilmiş, en iyi asidifikasyona ve proteolitik aktiviteye sahip 22 adet suş 16S rDNA dizi analizi ile tanımlanmıştır. Tanımlaması yapılan suşların 15’i (% 63 Enterococcus spp., 5’i (% 21, Lactococcus spp., 1’i (% 4 Lactobacillus spp. ve 1’i (% 4 Weissella spp. olarak belirlenmiştir. 15 adet Enterococcus spp. izolatından; 9’u (% 60 Enterococcus faecium, 4’ü (% 26.7 Enterococcus faecalis ve 2’si (% 13.3 Enterococcus durans olarak; 5 adet Lactococcus spp. izolatından, 3’ü (% 60 Lactococcus lactis subsp. lactis, 2’si (% 40 Lactococcus garvieae olarak tanımlanmıştır. Lactobacillus spp. ve Weissella spp. olarak tanımlanan suşların ise sırasıyla Lactobacillus casei ve Weissella viridescens olduğu tespit edilmiştir. Tanımlanan suşlar içerisinden aynı anda hem düşük proteolitik aktivite hem de yüksek asidifikasyon aktivitesi özelliği gösteren bir adet Lactococcus lactis subsp. lactis suşu, Enterokoklar arasından bir adet Enterococcus faecalis, bir adet Enterococcus faecium ve iki adet Enterococcus durans suşu en iyi starter kültür özelliklerine sahip suşlar olarak belirlenmiştir.

The in vitro activity of flomoxef compared to four other cephalosporins and imipenem.

Science.gov (United States)

Shah, P M; Knothe, H

1991-01-01

The antibacterial activity of the oxacephalosporin flomoxef was evaluated in comparison to cefpirome, cefuzoname, cefotaxime, ceftazidime, and imipenem against fresh clinical isolates. Flomoxef is an antibiotic with strong antibacterial activity against staphylococci including methicillin-resistant strains and streptococci with the exception of Enterococcus faecalis and Enterococcus faecium. It is very active against gram-negative cocci and rods including gram-positive and gram-negative anaerobes. Against Pseudomonas sp. flomoxef has no activity.

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

International Nuclear Information System (INIS)

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

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 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

Probiotic assessment of Enterococcus faecalis CP58 isolated from human gut.

Science.gov (United States)

Nueno-Palop, Carmen; Narbad, Arjan

2011-02-28

A total of seventy lactic acid bacteria (LAB) were isolated from the faeces of healthy humans and their identities were confirmed by sequencing of their 16S rDNA genes. Of these only 5 isolates were found to resist bile salts and indicated survival in the simulated in vitro digestion assay which reproduces the stomach and intestinal digestion indicating their tolerance to gastric enzymes and the low pH conditions. Species that showed the best resistance to these conditions were: Lactobacillus casei, Lactobacillus sp., uncultured bifidobacteria, Enterococcus faecalis and Streptococcus anginosus. These strains were investigated further to study their capacity to adhere to human intestinal Caco-2 cells. E. faecalis was the most adherent strain. Examination of the virulence determinants for this strain indicated that it was positive for efaAfs, gelE, agg, cpd, cob, ccf and cad, a profile that is similar to that of many E. faecalis isolates from food sources. The cytolysin biosynthetic genes cylA, cylB and cylM that are more associated with the clinical isolates of E. faecium were not detected in this strain. The antibiotic susceptibility tests indicated that the strain was sensitive to vancomycin, tetracycline, rifampicin and erythromycin but resistant only to kanamycin and chloramphenicol. These data suggest that the strain E. faecalis CP58 may be tested further for beneficial properties and developed as a new probiotic. Copyright © 2010 Elsevier B.V. All rights reserved.

Presence of Glycopeptide-Encoding Plasmids in Enterococcal Isolates from Food and Humans in Denmark

DEFF Research Database (Denmark)

Migura, Lourdes Garcia; Valenzuela, Antonio Jesus Sanchez; Jensen, Lars Bogø

2011-01-01

developed techniques for classification of plasmids. Replicons associated with sex pheromone-inducible plasmids were detected in all GR E. faecalis, whereas GR Enterococcus faecium contained plasmids known to be widely distributed among enterococci. vanA resistance is common in E. faecium isolates from meat...... and animals in Europe and is rarely found in E. faecalis. This article describes the first characterization of MGE from vanA mediated E. faecalis, thus linking this resistance genotype to pheromone responding plasmids....

Bacteriocinogenic potential and genotypic characterization of three ...

African Journals Online (AJOL)

Louiza

2015-08-06

Aug 6, 2015 ... Maximal activity from BRO2 strain was at pH 7 (20480 AU/ml) and ... Key words: Butter, milk, Enterococcus faecium, antibacterial activity, .... Phenotypic identification of enterococcal strains .... The effect of temperature on the.

Vancomycin-resistant Enterococcus faecium bacteraemia as a complication of Kayexalate (sodium polystyrene sulfonate, SPS) in sorbitol-induced ischaemic colitis.

Science.gov (United States)

Cerrud-Rodriguez, Roberto Christian; Alcaraz-Alvarez, Diego; Chiong, Brian Bobby; Ahmed, Abdurhman

2017-11-09

We present the case report of an 80-year-old woman with chronic kidney disease stage G5 admitted to the hospital with fluid overload and hyperkalaemia. Sodium polystyrene sulfonate (SPS, Kayexalate) in sorbitol suspension was given orally to treat her hyperkalaemia, which precipitated an episode of SPS in sorbitol-induced ischaemic colitis with the subsequent complication of vancomycin-resistant Enterococcus (VRE) bacteraemia. SPS (Kayexalate) in sorbitol suspension has been implicated in the development of intestinal necrosis. Sorbitol, which is added as a cathartic agent to decrease the chance of faecal impaction, may be primarily responsible through several proposed mechanisms. The gold standard of diagnosis is the presence of SPS crystals in the colon biopsy. On a MEDLINE search, no previous reports of a VRE bacteraemia as a complication of biopsy-confirmed SPS in sorbitol ischaemic colitis were found. To the best of our knowledge, ours would be the first such case ever reported. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Prevalence and Removal Efficiency of Enterococcal Species and Vancomycin-resistant Enterococci of a Hospital Wastewater Treatment Plant

Directory of Open Access Journals (Sweden)

Fatemeh Karimi

2016-12-01

Full Text Available Simultaneous presence of various antibiotics and bacteria in hospital wastewaters creates a suitable environment, in which the bacteria, such as ‎enterococci become resistant to the antibiotics. The aim of this study was to evaluate the performance of different units of the hospital wastewater treatment plant (HWTP to remove Enterococcus spp and Vancomycin-resistant Enterococcus (VRE. The study was performed on the 27 samples collected from HWTP in Hamedan, Iran during December 2014 to August 2015. Enterococcus spp and VRE were identified by biochemical tests and then the isolates were confirmed by PCR. Finally, the antibiotic susceptibility test was performed using disk diffusion methods. Of the 27 samples examined, 315 a total of enterococcal isolates were obtained. Of the 315 isolates of enterococci investigated, 162 (51.42% were identified as E. faecium, 87 (27.61% as E. hirae, 35 (11.11% as E. faecalis, 11 (3.5% as E. gallinarum, 7 (2.22% as E. casseliflavus, 4 (1.26% E. avium, and 9 (2.85% isolates VR E. faecium.The results of antibiotic susceptibility testing showed that of the total 315 isolates, 146 (46.34% were resistance to tetracycline, 9 (2.85% were resistance to vancomycin and Teicoplanin. Lower antibiotic resistance was seen with Nitrofurantoin 2 (1.26%. This study indicates a high prevalence of multidrug resistance among E. faecium isolated from HWTP, thus, it could be considered as a threat to the health and safety of ‎wastewater workers and even public health.

Linezolid-resistant enterococci in Polish hospitals: species, clonality and determinants of linezolid resistance.

Science.gov (United States)

Gawryszewska, I; Żabicka, D; Hryniewicz, W; Sadowy, E

2017-07-01

The significant increase of the linezolid-resistant enterococci (LRE) has been observed in Polish hospitals since 2012 and our study aimed at elucidating the possible reasons for this phenomenon. Polish LRE isolates were analysed by multilocus-sequence typing (MLST) and multiple locus variable-number tandem repeat (VNTR) analysis (MLVA), polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP) to establish clonal relatedness and mechanism of linezolid resistance, respectively. Fifty analysed LRE (2008-2015) included mostly Enterococcus faecium (82%) and Enterococcus faecalis (16%). Enterococcus faecium belonged to the hospital-adapted lineages 17/18 and 78, while E. faecalis isolates represented ST6, a hospital-associated type, and ST116, found in both humans and food-production animals. The G2576T 23S rRNA mutation was the most frequent (94%) mechanism of linezolid/tedizolid resistance of LRE. None of the isolates carried the plasmid-associated gene of Cfr methyltransferase, whereas optrA, encoding the ABC-type drug transporter, was identified in two E. faecalis isolates. In these isolates, optrA was located on a plasmid, transferable to both E. faecium and E. faecalis, whose partial (36.3 kb) sequence was 100% identical to the pE394 plasmid, identified previously in China in both clinical and farm animal isolates. The optrA-E. faecium transconjugant displayed a significant growth deficiency, in contrast to the optrA-E. faecalis. Our study indicates the role of mutation acquisition by hospital-adapted clones of enterococci as a major driver of increasing resistance to linezolid and tedizolid. Transferability and apparent lack of a biological cost of resistance suggest that E. faecalis may be a natural reservoir of optrA, an emerging mechanism of oxazolidinone resistance.

In Vivo Characterization of the Activation and Interaction of the VanR-VanS Two-Component Regulatory System Controlling Glycopeptide Antibiotic Resistance in Two Related Streptomyces Species

Czech Academy of Sciences Publication Activity Database

Novotná, Gabriela; Kwun, Min Jung, M.J.; Hong, H.J.

2016-01-01

Roč. 60, č. 3 (2016), s. 1627-1637 ISSN 0066-4804 Institutional support: RVO:61388971 Keywords : ENTEROCOCCUS-FAECIUM BM4147 * DEPSIPEPTIDE PEPTIDOGLYCAN PRECURSORS * BACTERIAL SIGNALING PROTEINS Subject RIV: EE - Microbiology, Virology Impact factor: 4.302, year: 2016

Characterization of a Bacteriocin-Like Substance Produced by a Vaginal Lactobacillus salivarius Strain

Science.gov (United States)

Ocaña, Virginia S.; Pesce de Ruiz Holgado, Aída A.; Nader-Macías, María Elena

1999-01-01

A novel bacteriocin-like substance produced by vaginal Lactobacillus salivarius subsp. salivarius CRL 1328 with activity against Enterococcus faecalis, Enterococcus faecium, and Neisseria gonorrhoeae was characterized. The highest level of production of this heat-resistant peptide or protein occurred during the late exponential phase. Its mode of action was shown to be bactericidal. L. salivarius subsp. salivarius CRL 1328 could be used for the design of a probiotic to prevent urogenital infections. PMID:10584033

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

Energy Technology Data Exchange (ETDEWEB)

Walanj, Rupa; Young, Paul; Baker, Heather M.; Baker, Edward N.; Metcalf, Peter [Laboratory of Structural Biology, School of Biological Sciences, University of Auckland, Auckland (New Zealand); Chow, Joseph W.; Lerner, Stephen [Division of Infectious Diseases, Wayne State University School of Medicine and VA Medical Center, Detroit, Michigan 48201 (United States); Vakulenko, Sergei [Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States); Smith, Clyde A., E-mail: csmith@slac.stanford.edu [Stanford Synchrotron Radiation Laboratory, Stanford University, Menlo Park, CA 94025 (United States); Laboratory of Structural Biology, School of Biological Sciences, University of Auckland, Auckland (New Zealand)

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.

Typing of vancomycin-resistant enterococci with MALDI-TOF mass spectrometry in a nosocomial outbreak setting

DEFF Research Database (Denmark)

Holzknecht, B J; Dargis, R; Pedersen, M

2018-01-01

OBJECTIVES: To investigate the usefulness of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) typing as a first-line epidemiological tool in a nosocomial outbreak of vancomycin-resistant Enterococcus faecium (VREfm). METHODS: Fifty-five VREfm isolates...

Diversity of enterococcal species and characterization of high-level aminoglycoside resistant enterococci of samples of wastewater and surface water in Tunisia.

Science.gov (United States)

Ben Said, Leila; Klibi, Naouel; Lozano, Carmen; Dziri, Raoudha; Ben Slama, Karim; Boudabous, Abdellatif; Torres, Carmen

2015-10-15

One hundred-fourteen samples of wastewater (n=64) and surface-water (n=50) were inoculated in Slanetz-Bartley agar plates supplemented or not with gentamicin (SB-Gen and SB plates, respectively) for enterococci recovery. Enterococci were obtained from 75% of tested samples in SB media (72% in wastewater; 78% in surface-water), and 85 enterococcal isolates (one/positive-sample) were obtained. Enterococcus faecium was the most prevalent species (63.5%), followed by Enterococcus faecalis (20%), Enterococcus hirae (9.4%), Enterococcus casseliflavus (4.7%), and Enterococcus gallinarum/Enterococcus durans (2.4%). Antibiotic resistance detected among these enterococci was as follows [percentage/detected gene (number isolates)]: kanamycin [29%/aph(3')-IIIa (n=22)], streptomycin [8%/ant(6)-Ia (n=4)], erythromycin [44%/erm(B) (n=34)], tetracycline [18%/tet(M) (n=6)/tet(M)-tet(L) (n=9)], chloramphenicol [2%/cat(A) (n=1)], ciprofloxacin [7%] and trimethoprim-sulfamethoxazole [94%]. High-level-gentamicin resistant (HLR-G) enterococci were recovered from 15 samples in SB-Gen or SB plates [12/64 samples of wastewater (19%) and 3/50 samples of surface-water (6%)]; HLR-G isolates were identified as E. faecium (n=7), E. faecalis (n=6), and E. casseliflavus (n=2). These HLR-G enterococci carried the aac(6')-Ie-aph(2")-Ia and erm(B) genes, in addition to aph(3')-IIIa (n=10), ant(6)-Ia (n=9), tet(M) (n=13), tet(L) (n=8) and cat(A) genes (n=2). Three HLR-G enterococci carried the esp virulence gene. Sequence-types detected among HLR-G enterococci were as follows: E. faecalis (ST480, ST314, ST202, ST55, and the new ones ST531 and ST532) and E. faecium (ST327, ST12, ST296, and the new ones ST985 and ST986). Thirty-two different PFGE patterns were detected among 36 high-level-aminoglycoside-resistant enterococci recovered in water samples. Diverse genetic lineages of HLR-G enterococci were detected in wastewater and surface-water in Tunisia. Water can represent an important source for the

Antimicrobial growth promoter ban and resistance to macrolides and vancomycin in enterococci from pigs

DEFF Research Database (Denmark)

Boerlin, P.; Wissing, A.; Aarestrup, Frank Møller

2001-01-01

Ninety-six enterococcus isolates from fecal samples of pigs receiving tylosin as an antimicrobial growth promoter and 59 isolates obtained in the same farms 5 to 6 months after the ban of antimicrobial growth promoters in Switzerland were tested for susceptibility to nine antimicrobial agents....... A clear decrease in resistance to macrolides, lincosamides, and tetracycline was visible after the ban. Vancomycin-resistant Enterococcus faecium belonged to the same clonal lineage as vancomycin-resistant isolates previously isolated from Danish pigs....

Pathogens Present in Acute Mangled Extremities From Afghanistan and Subsequent Pathogen Recovery

Science.gov (United States)

2015-01-01

0/pre-), Kloeckera spp (PID 0/post-) 4 Aspergillus niger (PID 5) 3 LLE 3 P. stutzeri (PID 0/pre-), P. fluorescens (PID 0/pre-), CNS (PID 0/pre...Streptococcus viridans group (PID 0/post-) 4 Penicillium spp (PID 5), Aspergillus spp (PID 5), Enterococcus hirae (PID 5), Bacillus spp (PID 5) 5 P...Penicillium spp (PID 1), Aspergillus spp (PID 1), Enterococcus faecium (PID 1) 5 E. coli (PID 7) LLE, left lower extremity; RLE, right lower extremity

Author Details

African Journals Online (AJOL)

Bacteriocinogenic potential and genotypic characterization of three Enterococcus faecium isolates from Algerian raw milk and traditional butter. Abstract PDF · Vol 13, No 45 (2014) - Articles Statistical optimization of lactic acid production by Lactococcus lactis strain, using the central composite experimental design

Sewage sludge and liquid pig manure as possible sources of antibiotic resistant bacteria.

Science.gov (United States)

Hölzel, Christina S; Schwaiger, Karin; Harms, Katrin; Küchenhoff, Helmut; Kunz, Anne; Meyer, Karsten; Müller, Christa; Bauer, Johann

2010-05-01

Within the last decades, the environmental spread of antibiotic resistant bacteria has become a topic of concern. In this study, liquid pig manure (n=305) and sewage sludge (n=111) - used as agricultural fertilizers between 2002 and 2005 - were investigated for the presence of Escherichia coli, Enterococcus faecalis and Enterococcus faecium. Bacteria were tested for their resistance against 40 chemotherapeutics including several "reserve drugs". E. coli (n=613) from pig manure were at a significantly higher degree resistant to streptomycin, doxycycline, spectinomycin, cotrimoxazole, and chloramphenicol than E. coli (n=116) from sewage sludge. Enterococci (Ent. faecalis, n=387, and Ent. faecium, n=183) from pig manure were significantly more often resistant to high levels of doxycycline, rifampicin, erythromycin, and streptomycin than Ent. faecalis (n=44) and Ent. faecium (n=125) from sewage sludge. Significant differences in enterococcal resistance were also seen for tylosin, chloramphenicol, gentamicin high level, fosfomycin, clindamicin, enrofloxacin, moxifloxacin, nitrofurantoin, and quinupristin/dalfopristin. By contrast, aminopenicillins were more effective in enterococci from pig manure, and mean MIC-values of piperacillin+tazobactam and third generation cefalosporines were significantly lower in E. coli from pig manure than in E. coli from sewage sludge. 13.4% (E. coli) to 25.3% (Ent. faecium) of pig manure isolates were high-level multiresistant to substances from more than three different classes of antimicrobial agents. In sewage sludge, high-level-multiresistance reached from 0% (Ent. faecalis) to 16% (Ent. faecium). High rates of (multi-) resistant bacteria in pig manure emphasize the need for a prudent - cautious - use of antibiotics in farm animals. Copyright 2010 Elsevier Inc. All rights reserved.

Resistencia a antimicrobianos y evaluación del tratamiento combinado en la septicemia neonatal

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María Espino Hernández

2003-04-01

Full Text Available OBJETIVOS: Estudiar la resistencia a los antibióticos de las cepas bacterianas aisladas de pacientes con septicemia neonatal en un hospital ginecobstétrico de La Habana, Cuba, en el período comprendido entre enero de 1994 y diciembre de 1998, y evaluar el valor predictivo del método del "tablero de damas" (checkerboard para seleccionar el tratamiento con combinaciones de antibióticos en pacientes graves. MÉTODOS: Se estudió a 229 neonatos, a quienes se les extrajo sangre para hemocultivo y estudios de sensibilidad a antimicrobianos. El estudio de la susceptibilidad de las cepas se realizó por el método de microdilución en caldo y se utilizó el tablero de damas en bandejas de caldo para evaluar la eficacia del tratamiento antimicrobiano combinado. RESULTADOS: Cincuenta por ciento de las cepas aisladas de Staphylococcus spp. coagulasa-negativas y 37% de las cepas de S. aureus, principales agentes causales de sepsis neonatal, fueron resistentes a la meticilina. De ellas, 94,5% resultaron resistentes a varios antibióticos. Cuatro cepas de Staphylococcus spp. coagulasa-negativas y una de Enterococcus faecium fueron resistentes a la vancomicina (concentración mínima inhibidora = 128 myg/mL. Se observó una alta probabilidad de eficacia clínica (P < 0,01 con combinaciones de antibióticos que mostraron un efecto sinérgico in vitro, mientras que las reacciones antagónicas se correspondieron con la probabilidad altamente significativa de fracaso terapéutico clínico. DISCUSIÓN: La principal causa de septicemia neonatal en la Unidad de Cuidados Intensivos del Hospital "América Arias" en La Habana, Cuba, está constituida por las cepas de estafilococo resistentes a la meticilina y a otros antibióticos. En pacientes graves (atendiendo a lo establecido en el programa de política de este centro, la primera línea de tratamiento la constituye la combinación de un antibiótico aminoglucósido con un betalactámico. Este estudio demostr

Genomic analysis of 495 vancomycin-resistant Enterococcus faecium reveals broad dissemination of a vanA plasmid in more than 19 clones from Copenhagen, Denmark

DEFF Research Database (Denmark)

Pinholt, Mette; Gumpert, Heidi; Bayliss, Sion

2017-01-01

. The majority of the isolates were located in three groups (n = 44, 100 and 218) and clonal spread of VREfm between wards and hospitals was identified. Five Tn1546-like transposon types were identified. A dominant truncated transposon (type 4, 92%) was spread across all but one VREfm group. The closed van......A plasmid was highly covered by reads from isolates containing the type 4 transposon. CONCLUSIONS: This study suggests that it was the dissemination of the type 4 Tn1546-like transposon and plasmid via horizontal transfer to multiple populations of E. faecium, followed by clonal spread of new VREfm clones...

The Potential of Lactobacillus casei and Entercoccus faecium Combination as a Preventive Probiotic Against Entamoeba.

Science.gov (United States)

Sarjapuram, Nitya; Mekala, Niharika; Singh, Meetali; Tatu, Utpal

2017-06-01

Travellers' diarrhoea caused by enteric protozoa like Entamoeba histolytica is among the most common protozoan diseases in developing countries. In developing countries, amoebiasis is the second most prevalent protozoan disease. This protozoan parasite is often known to coexist as a part of the normal gut microbiota. It is estimated that around 50-60 % of population in developing countries might be harbouring Entamoeba in an asymptomatic manner. Due to physiological perturbation or upon immuno-compromise, it can become virulent and then cause diarrhoea, bloody stools and may invade other organs if left untreated. Nitroimidazole drugs, namely metronidazole and tinidazole, are widely used to treat protozoan infections. These drugs often show dose-dependent side effects. With emerging antibiotic resistance, novel therapeutics to prevent parasitic infections is required. This study aims to study effect of probiotics on prevention of Amoebiasis. In this study, we have investigated the effect of selected probiotics on the growth of Entamoeba. From the list of probiotics being currently used, five bacterial strains were selected for testing. These probiotic strains were co-cultured with Entamoeba, and their effect on Entamoeba proliferation was checked. Of the five probiotics chosen, individual treatments of Lactobacillus casei and Enterococcus faecium showed a significant reduction of up to 71 % in parasite survival only at higher CFUs. When the two probiotics were used in combination, the percentage of survival reduced gradually further to 80 % at a total CFU of 10 9  cells/ml of bacteria. The study lays the foundation for providing cost-effective prophylactic treatment for amoebiasis without the overuse of antibiotics.

Fermentation of D-Tagatose by Human Intestinal Bacteria and Dairy Lactic Acid Bacteria

OpenAIRE

Bertelsen, Hans; Andersen, Hans; Tvede, Michael

2011-01-01

A number of 174 normal or pathogenic human enteric bacteria and dairy lactic acid bacteria were screened for D-tagatose fermentation by incubation for 48 hours. Selection criteria for fermentation employed included a drop in pH below 5.5 and a distance to controls of more than 0.5. Only a few of the normal occurring enteric human bacteria were able to ferment D-tagatose, among those Enterococcus faecalis, Enterococcus faecium and Lactobacillus strains. D-Tagatose fermentation seems to be comm...

Utilization of blood cultures in Danish hospitals

DEFF Research Database (Denmark)

Gubbels, S; Nielsen, J; Voldstedlund, M

2015-01-01

This national population-based study was conducted as part of the development of a national automated surveillance system for hospital-acquired bacteraemia and ascertains the utilization of blood cultures (BCs). A primary objective was to understand how local differences may affect interpretation......, Streptococcus pneumoniae, Enterococcus faecium, Enterococcus faecalis, Pseudomonas aeruginosa, Candida albicans, Enterobacter cloacae and Klebsiella oxytoca, accounted for 74.7% of agents for this purpose classified as pathogenic. An increase in BCs and positive BCs was observed over time, particularly among...

Obras de fábrica resistentes. Consideraciones generales de cálculo

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Jenaro Garrido, José María

1986-10-01

Full Text Available This work studies de resisting capacity of the non reinforced masonry works to normal requirements from the knowledge of the nominal value to compressive resistance of its elements, or from the results from compression tests carried out on masses or on masonry samples. The obtained expressions for homogeneous sections are also valid for sections that, because of their cavities, they can be considered heterogeneous, allowing a determination of its resistant behaviour by means of the introduction of the conceipt of resistant homogeneous equivalent section. Finaly it includes a study on deforming and buckling of the masonry works to which diverse expressions gathered already in the Model Code CEB-FIP and in the Instruction in force EH'82 for Concrete Works are applied.El presente artículo recoge un estudio de la capacidad resistente de las obras de fábrica no armadas ante las solicitaciones normales, a partir del conocimiento del valor nominal de la resistencia a compresión de los elementos componentes o de los resultados de ensayos a compresión realizados sobre macizos o probetas de obra de fábrica. Las expresiones obtenidas para secciones homogéneas se extienden a secciones que por comprender cavidades hayan de considerarse heterogéneas, haciendo posible una determinación de su comportamiento resistente mediante la introducción del concepto de sección resistente homogénea equivalente. Finalmente se incluye un estudio sobre la deformabilidad y pandeo de las obras de fábrica a los que se aplican diversas expresiones ya recogidas en el Código Modelo CEB-FIP y en la vigente Instrucción EH-82 para obras de hormigón.

Molecular Analysis of Vancomycin-Resistant Enterococci Isolated from Regional Hospitals in Trinidad and Tobago

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Patrick E. Akpaka

2016-01-01

Full Text Available Geographic spread of vancomycin-resistant enterococci (VRE clones in cities, countries, or even continents has been identified by molecular techniques. This study aimed at characterizing virulent genes and determining genetic relatedness of 45 VRE isolates from Trinidad and Tobago using molecular tools, including polymerase chain reaction, pulsed-field gel electrophoresis (PFGE, and Random Amplification Polymorphic DNA (RAPD. The majority (84% of the isolates were Enterococcus faecium possessing vanA gene while the rest (16% were Enterococcus faecalis possessing vanB. The esp gene was found in all 45 VRE isolates while hyl genes were found only in E. faecium species. The E. faecium species expressed five distinct PFGE patterns. The predominant clones with similar or common patterns belonged to clones one and three, and each had 11 (29% of the VRE isolates. Plasmid content was identified in representative isolates from each clonal group. By contrast, the E. faecalis species had one PFGE pattern suggesting the presence of an occult and limited clonal spread. The emergence of VRE in the country seems to be related to intra/interhospital dissemination of an epidemic clone carrying the vanA element. Therefore, infection control measures will be warranted to prevent any potential outbreak and spread of VRE in the country.

Integrated Detection of Pathogens and Host Biomarkers for Wounds

Science.gov (United States)

2012-04-01

None None TN631B Enterococcus faecium None ZB191B Enterobacter cloacae Acinetobacter baumannii Enterobacter cloacae plasmid pEC01 These initial...Streptomyces roseosporus HERV K113 ZB191B Enterobacter cloacae Enterobacter cloacae plasmid pEC01 Escherichia coli plasmid pIGRW12 Plasmid

Complete genome sequence of Brachybacterium faecium type strain (Schefferle 6-10T)

Energy Technology Data Exchange (ETDEWEB)

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.

Conservation of Ebp-type pilus genes among Enterococci and demonstration of their role in adherence of Enterococcus faecalis to human platelets.

Science.gov (United States)

Nallapareddy, Sreedhar R; Sillanpää, Jouko; Mitchell, Jennifer; Singh, Kavindra V; Chowdhury, Shahreen A; Weinstock, George M; Sullam, Paul M; Murray, Barbara E

2011-07-01

Ebp are endocarditis- and biofilm-associated pili of Enterococcus faecalis that are also important in experimental urinary tract infections (UTIs). Our analyses, using available genomes, found that the ebp locus is unique to enterococci. In E. faecalis, the ebp locus is very highly conserved and only 1/473 E. faecalis isolates tested lacked ebpABC, while only 1.2% had the bee pilus locus. No other pilus-encoding operon was identified in 55 available genomes, indicating that the vast majority of E. faecalis strains (unlike Enterococcus faecium and streptococci) have a single pilus locus. Surface expression studies showed that Ebp pili were produced in vitro by 91/91 brain heart infusion (BHI) plus serum-grown E. faecalis isolates and that strain OG1RF expressed pili at even higher levels in rat endocarditis vegetations. However, Ebp expression was restricted to 30 to 72% of E. faecalis cells, consistent with a bistability mode of expression. We also evaluated E. faecalis interactions with human platelets and found that growth of E. faecalis in BHI plus serum significantly enhanced adherence to human platelets and that sortase deletion mutants (the ΔsrtA, Δbps, and ΔbpsΔsrtA mutants) were markedly defective. Further studies identified that Ebp pili, but not the microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) Ace and Fss2, mediate adherence of E. faecalis to platelets. Taken together, our data show that the immunogenic (in human endocarditis patients) and commonly expressed Ebp pili, which are known to be important for experimental endocarditis, are highly conserved and mediate adherence to platelets, suggesting that Ebp pili may be a reasonable immunotherapeutic target for prevention or possibly treatment of endocarditis caused by this species.

Antibiotic susceptibility of enterococci isolated from traditional fermented meat products.

Science.gov (United States)

Barbosa, J; Ferreira, V; Teixeira, P

2009-08-01

Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chouriça de Vinhais and Salpicão de Vinhais, fermented meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

Arquitectura sismo-resistente: respuesta morfológica

Directory of Open Access Journals (Sweden)

Giulani, Hugo

1994-12-01

Full Text Available In the previous reports (1 and (2 we raised the question of the necessity to develop an Earthquake-Resistant Architecture which would make the integral solution of the seismic problem in buildings possible. We established the grounds, objectives, basic principles and methodology for defining the guidelines to be followed in making the architectural design and structural earthquake-resistant design compatible. The present report brings the proposal of an architectural response from the morphological point of view, allowing us to reach an adequate final form which consists of eliminating all the incompatibilities produced by the seismic demands and determining factors, in other words, we search for an architectural design which, owing to its very morphology, is able to satisfy the said conditions; an "Adequate Final Form" which in itself avoids the bothersome guidelines for making the structural and architectural designs compatible, transforming them into morphological responses to each seismic determining factor.

En informes anteriores (1 y (2 planteamos la necesidad de desarrollar una Arquitectura Sismo-resistente, que posibilite la solución integral del problema sísmico de los edificios. Se establecieron los fundamentos, objetivos, principios básicos y metodología para deducir las pautas de compatibilización del diseño arquitectónico con el diseño estructural sismo-resistente. En el presente informe se propone una respuesta arquitectónica desde la morfología, que permite llegar a una forma final ajustada, en el sentido de eliminar toda incompatibilidad respecto de las exigencias o condicionantes sísmicos. Es decir, un proyecto arquitectónico que por su propia morfología satisfaga dichos condicionantes. Una "Forma Final Ajustada" que evita, por sí misma, las engorrosas pautas de compatibilización del diseño estructural con el diseño arquitectónico, transformándolas en respuestas morfológicas a cada condicionante sísmico.

Avaliação da capacidade resistente última de estacas em compressão usando análises em tensão/deformação

OpenAIRE

Vieira, Ana Rita Ribeiro

2013-01-01

Dissertação para obtenção do Grau de Mestre em Engenharia Civil - Ramo de Estruturas e Geotecnia Nesta dissertação avalia-se a capacidade resistente última de estacas em compressão usando análises em tensão/deformação. A capacidade resistente última das estacas é avaliada através do programa computacional de elementos finitos Plaxis 2D v. 8 e é comparada com a capacidade resistente última prevista por métodos de extrapolação da curva carga vs. assetamento de ensaios de carga que não ...

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

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Peng Li

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

Rational approaches to the therapy of nosocomial infections caused by gram-positive microorganisms in cancer p

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V. V. Aginova

2017-01-01

Full Text Available Nosocomial infections caused by gram-positive organisms, including Staphylococcus aureus and enterococci (Enterococcus faecium and Enterococcus faecalis are steadily increasing in almost all clinics around the world. Cancer patients have a higher risk of hospital-acquired infections than non-cancer patients. Cancer patients are immunosuppressed due to increased use of broad-spectrum antibiotics and chemotherapy drugs, radiation therapy, surgery and use of steroids. This paper presents an analysis of resistance of gram-positive bacterial pathogens to antimicrobial agents to determine treatment strategy for cancer patients.

Effects of dietary probiotic supplementation on promoting ...

African Journals Online (AJOL)

hope&shola

2010-10-25

Oct 25, 2010 ... The birds in group A received control diet during the experiment but those in ... genera displayed a growth-promoting effect that was comparable to control diet and also decreased .... Table 3. Effects of dietary probiotics on evolution of broiler weekly BW in control, Enterococcus faecium, and Bifidobacterium.

Effects of dietary probiotic supplementation on promoting ...

African Journals Online (AJOL)

The aim of this study was to investigate the effect of two commercially-available probiotics, based on Enterococcus faecium and Bifidobacterium genera on performance and cholesterol and triglyceride amounts of broiler chicks' sera. One hundred and fifty-six (156), day-old, Ross chicks were randomly divided into groups A, ...

Susceptibilidad antimicrobiana de Staphylococcus aureus sensible, con sensibilidad "BORDERLINE" y resistentes a la meticilina

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Carlos Alberto Mendoza Ticona

2003-10-01

Full Text Available Objetivo: Determinar las susceptibilidad a diversos antibacterianos de tres categorías de S. aureus según su sensibilidad a la meticilina. Materiales y Métodos: Se aislaron 76 cepas de S. aureus que colonizaban pacientes y personal de salud de tres servicios del Hospital Honorio Delgado de Arequipa, de los cuales 36 fueron sensibles a meticilina (MSSA, 15 con susceptibilidad "borderline" (BORSA y 25 fueron resistentes a la meticilina (MRSA. Se les sometió a antibiograma a 14 antibacterianos. Resultados: El único antibiótico al cual todas los aislamientos fueron sensibles fue vancomicina. Los MRSA fueron resistentes a todos los b-lactámicos excepto imipenem que obtuvo 64% de susceptibilidad. Los BORSA mantuvieron un 80% de sensibilidad a cefalotina y un 100% al imipenem. Los antibióticos cefalotina, imipenem, ciprofloxacina, cotrimoxazol, rifampicina, eritromicina, tetraciclina, cloranfenicol, lincomicina y gentamicina tuvieron sensibilidades variables (p<0.01 entre las tres categorías; una mayor proporción de MSSA fue sensible a estos antibióticos, luego los BORSA y finalmente los MRSA. Las cepas multi-resistentes fueron mucho más frecuentes en los MRSA que en los otros dos grupos (p <0.01. Conclusión: Existe en nuestro medio cepas de S. aureus con resistencia "borderline" a meticilina. Hay diferencias entre la sensibilidad a diversos antimicrobianos entre los tres grupos de S. aureus. Esta diferenciación podría beneficiar una terapia antimicrobiana más racional. Se debe aplicar en todo aislamiento de S. aureus las recomendaciones internacionales para la detección de meticilino resistencia.

Conservation of Ebp-Type Pilus Genes among Enterococci and Demonstration of Their Role in Adherence of Enterococcus faecalis to Human Platelets ▿ †

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Nallapareddy, Sreedhar R.; Sillanpää, Jouko; Mitchell, Jennifer; Singh, Kavindra V.; Chowdhury, Shahreen A.; Weinstock, George M.; Sullam, Paul M.; Murray, Barbara E.

2011-01-01

Ebp are endocarditis- and biofilm-associated pili of Enterococcus faecalis that are also important in experimental urinary tract infections (UTIs). Our analyses, using available genomes, found that the ebp locus is unique to enterococci. In E. faecalis, the ebp locus is very highly conserved and only 1/473 E. faecalis isolates tested lacked ebpABC, while only 1.2% had the bee pilus locus. No other pilus-encoding operon was identified in 55 available genomes, indicating that the vast majority of E. faecalis strains (unlike Enterococcus faecium and streptococci) have a single pilus locus. Surface expression studies showed that Ebp pili were produced in vitro by 91/91 brain heart infusion (BHI) plus serum-grown E. faecalis isolates and that strain OG1RF expressed pili at even higher levels in rat endocarditis vegetations. However, Ebp expression was restricted to 30 to 72% of E. faecalis cells, consistent with a bistability mode of expression. We also evaluated E. faecalis interactions with human platelets and found that growth of E. faecalis in BHI plus serum significantly enhanced adherence to human platelets and that sortase deletion mutants (the ΔsrtA, Δbps, and ΔbpsΔsrtA mutants) were markedly defective. Further studies identified that Ebp pili, but not the microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) Ace and Fss2, mediate adherence of E. faecalis to platelets. Taken together, our data show that the immunogenic (in human endocarditis patients) and commonly expressed Ebp pili, which are known to be important for experimental endocarditis, are highly conserved and mediate adherence to platelets, suggesting that Ebp pili may be a reasonable immunotherapeutic target for prevention or possibly treatment of endocarditis caused by this species. PMID:21502588

Heat injury and recovery of Streptococcus faecium associated with the souring of chub-packed luncheon meat.

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Bell, R G; De Lacy, K M

1984-10-01

The presence of NaCl in the heating medium provided some protection from lethal heat damage for cells of a Streptococcus faecium strain isolated from luncheon meat whereas the presence of NaNO2 either alone or in addition to NaCl, had no significant effect on cell survival. Subsequent recovery and growth of heat-damaged cells was retarded by the presence of NaCl. When NaNO2 was present in addition to NaCl the inhibitory effect of the latter was reduced. These principal components of the luncheon-meat-cure are apparently opposed in their activities on post-heating recovery and growth of Strep. faecium. Product stability, i.e. duration of the lag before growth occurs, is directly related to the severity of the heat treatment and to the concentration of NaCl in the product. Therefore the resistance of pasteurized chub-packed luncheon meat to streptococcal spoilage during storage at temperatures conducive to microbial growth results from a prolonged heat-induced salt-maintained pre-growth adjustment phase rather than to any inherent inhibitory property of the luncheon meat to the growth of non-heat-damaged Strep. faecium cells.

Significance and survival of Enterococci during the house fly development.

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Ghosh, Anuradha; Akhtar, Mastura; Holderman, Chris; Zurek, Ludek

2014-01-01

House flies are among the most important nonbiting insect pests of medical and veterinary importance. Larvae develop in decaying organic substrates and their survival strictly depends on an active microbial community. House flies have been implicated in the ecology and transmission of enterococci, including multi-antibiotic-resistant and virulent strains of Enterococcus faecalis. In this study, eight American Type Culture Collection type strains of enterococci including Enterococcus avium, Enterococcus casseliflavus, Enterococcus durans, Enterococcus hirae, Enterococcus mundtii, Enterococcus gallinarum, Enterococcusfaecalis, and Enterococcusfaecium were evaluated for their significance in the development of house flies from eggs to adults in bacterial feeding assays. Furthermore, the bacterial colonization of the gut of teneral flies as well as the importance of several virulence traits of E. faecalis in larval mortality was assessed. Overall survival of house flies (egg to adult) was significantly higher when grown with typically nonpathogenic enterococcal species such as E. hirae (76.0% survival), E. durans (64.0%), and E. avium (64.0%) compared with that with clinically important species E. faecalis (24.0%) and E. faecium (36.0%). However, no significant differences in survival of house fly larvae were detected when grown with E. faecalis strains carrying various virulence traits, including isogenic mutants of the human clinical isolate E. faecalis V583 with in-frame deletions of gelatinase, serine protease, and capsular polysaccharide serotype C. Enterococci were commonly detected in fly puparia (range: 75-100%; concentration: 103-105 CFU/puparium);however, the prevalence of enterococci in teneral flies varied greatly: from 25.0 (E. casseliflavus) to 89.5% (E. hirae). In conclusion, depending on the species, enterococci variably support house fly larval development and colonize the gut of teneral adults. The human pathogenic species, E. faecalis and E. faecium

Meningitis associated with Vancomycin resistant Enterococcus casseliflavus: First report

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Nilay Sefa Uçar

2011-12-01

Full Text Available Enterococci are present in the gastrointestinal system as normal floral components. In the past two decades membersof the genus Enterococcus have emerged as important nosocomial pathogens worldwide. Enterococci may cause arange of different disorders such as urinary tract, intraabdominal, and wound infections, as well as endocarditis, meningitisand bacteraemia. Nosocomial enterococcal meningitis is most commonly observed following ventriculoperitonealshunt operations. Vancomycin resistant enterococcus (VRE represents 30% of all enterococci infections.This report presents a vancomycin-resistant Enterococcus casseliflavus meningitis case in a 66-year-old patient withventriculoperitoneal shunt, which has not been reported in the literature before. Successful outcomes were obtainedwith daptomycin plus linezolid combined treatment in VRE meningitis. Treatment recommendations in VRE meningitisare also discussed in this article. J Microbiol Infect Dis 2011;1 (3:138-140

9230 FECAL ENTEROCOCCUS/STREPTOCOCCUS GROUPS

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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...

Staphylococcus aureus resistente a vancomicina.

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Carlos Andrés Rodríguez

2005-12-01

Full Text Available Objetivo. Revisar la evolución y mecanismos moleculares de la resistencia de Staphylococcus aureus a vancomicina. Fuente de los datos. Se consultó la base de datos MEDLINE y se seleccionaron artículos tipo reportes de caso, estudios bioquímicos, de microscopía electrónica y biología molecular pertinentes. Síntesis. Después de casi 40 años de eficacia ininterrumpida de la vancomicina, en 1997 se reportaron los primeros casos de fracaso terapéutico debido a cepas de Staphylococcus aureus con resistencia intermedia, denominadas VISA (concentración inhibitoria mínima, CIM, 8 a 16 ?g/ml, así como a cepas con resistencia heterogénea hVISA (CIM global = 4 ?g/ml, pero con subpoblaciones VISA, en las cuales la resistencia está mediada por engrosamiento de la pared celular y disminución de su entrecruzamiento, lo que afecta la llegada del antibiótico al blanco principal, los monómeros del peptidoglicano en la membrana plasmática. En 2002 se aisló la primera de las 3 cepas reportadas hasta la fecha con resistencia total al antibiótico, denominadas VRSA (CIM>32 ?g/ml, en las que se encontró el transposón Tn1546 proveniente de Enterococcus spp, responsable del reemplazo de la terminación D-Ala-D-Ala por D-Ala-Dlactato en los precursores de la pared celular con pérdida de la afinidad por el glicopéptido. Conclusiones. La resistencia a vancomicina es una realidad en S. aureus, mediada en el caso de VISA por alteraciones en la pared celular que atrapan el antibiótico antes de llegar al sitio de acción, y en el caso de VRSA, por transferencia desde Enterococcus spp. de genes que llevan a la modificación del blanco molecular.

Fagotipagem de cepas de Staphylococcus aureus resistentes a antibióticos, isoladas de leite

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Wanderley Pereira de Araújo

1998-01-01

Full Text Available A partir de amostras de leite cru foram isoladas 201 cepas de S. aureus, as quais foram submetidas a provas de resistência a antibióticos pelo método dos discos impregnados com os seguintes antibacterianos: amicacina, ampicilina, cefalotina, cefoxitina, cloranfenicol, clindamicina, oxacilina, penicilina, tetraciclina, tobramicina e vancomicina. Com exceção de 88 (43,8%, 90 (44,8%, 24 (11,9% e 40 (19,9% cepas resistentes à penicilina, ampicilina, cloranfenicol e tetraciclina, respectivamente, a maioria das 201 cepas (95% ou mais foi sensível aos antibióticos utilizados. As cepas resistentes a estes quatro antibióticos foram fagotipadas, empregando-se os Conjuntos Básicos Internacionais de bacteriófagos para cepas de origem humana e bovina, verificando-se que houve predomínio de cepas sensíveis a fagos dos grupos III e III/NC do conjunto básico humano e a fagos dos grupos III, IV e da associação III/IV do conjunto bovino.

Estrategias de afrontamiento y personalidad resistente en pacientes de cuidados paliativos. Un estudio preliminar

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CECILIA PEÑACOBA PUENTE

2005-01-01

Full Text Available La medicina paliativa se dedica al cuidado de los pacientes con enfermedades en fase terminal. En España, existen varias unidades de cuidados paliativos, sin embargo, no en todas se lleva a cabo una intervención multidisciplinaria lo cual es esencial para conseguir que una persona muera en una situación de bienestar y con la mejor calidad posible. El objetivo de este estudio es analizar las estrategias de afrontamiento existentes en los enfermos ingresados en unidades de cuidados paliativos en fase de aceptación y su relación con la personalidad resistente. Para ello, se administró un instrumento corto en forma de entrevista. Los resultados encontrados muestran que este tipo de pacientes utilizan estrategias de afrontamiento positivas como acción para resolver problemas, búsqueda de recompensas alternativas y reevaluación positiva. Por otro lado, un aspecto de la personalidad resistente encontrada en estos pacientes es el reto lo cual indica que estos pacientes viven esta experiencia como una oportunidad de desarrollo personal.

Consumption of Camembert cheese stimulates commensal enterococci in healthy human intestinal microbiota.

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Firmesse, Olivier; Rabot, Sylvie; Bermúdez-Humarán, Luis G; Corthier, Gérard; Furet, Jean-Pierre

2007-11-01

Enterococci are natural inhabitants of the human gastrointestinal tract and the main Gram-positive and facultative anaerobic cocci recovered in human faeces. They are also present in a variety of fermented dairy and meat products, and some rare isolates are responsible for severe infections such as endocarditis and meningitis. The aim of the present study was to evaluate the effect of Camembert cheese consumption by healthy human volunteers on the faecal enterococcal population. A highly specific real-time quantitative PCR approach was designed and used to type enterococcal species in human faeces. Two species were found, Enterococcus faecalis and Enterococcus faecium, and only the Enterococcus faecalis population was significantly enhanced after Camembert cheese consumption, whereas Escherichia coli population and the dominant microbiota remained unaffected throughout the trial.

Enterococcus faecalis infective endocarditis

DEFF Research Database (Denmark)

Dahl, Anders; Rasmussen, Rasmus V; Bundgaard, Henning

2013-01-01

Because of the nephrotoxic effects of aminoglycosides, the Danish guidelines on infective endocarditis were changed in January 2007, reducing gentamicin treatment in enterococcal infective endocarditis from 4 to 6 weeks to only 2 weeks. In this pilot study, we compare outcomes in patients...... with Enterococcus faecalis infective endocarditis treated in the years before and after endorsement of these new recommendations....

Phytochemical analysis and antibacterial activities extracts of mangrove leaf against the growth of some pathogenic bacteria.

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Alizadeh Behbahani, Behrooz; Tabatabaei Yazdi, Farideh; Shahidi, Fakhri; Noorbakhsh, Hamid; Vasiee, Alireza; Alghooneh, Ali

2018-01-01

In this study, the effects of water, ethanol, methanol and glycerin at five levels (0, 31.25, 83.33, 125 and 250 ml) were investigated on the efficiency of mangrove leaf extraction using mixture optimal design. The antimicrobial effect of the extracts on Streptococcus pneumoniae, Enterococcus faecium and Klebsiella pneumoniae was evaluated using disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. The mangrove leaf extraction components were identified through gas chromatography/mass spectrometry (GC/MS). Phytochemical analysis (alkaloids, tannins, saponins, flavone and glycosides) were evaluated based on qualitative methods. Antioxidant activity of extracts was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant potential (FRAP) methods. Maximum antimicrobial effect was observed in Enterococcus faecium and highest resistance against mangrove leaf extract in Enterococcus faecium and Klebsiella pneumoniae, respectively. Increasing concentration of mangrove extracts had a significant effect (p ≤ 0.05) on inhibition zone diameter. The MICs of the mangrove leaf extraction varied from 4 mg/ml to 16 mg/ml. The optimum formulation was found to contain glycerin (0 ml), water (28.22 ml), methanol (59.83 ml) and ethanol (161.95 ml). The results showed that the highest antioxidant activity was related to optimum extract of mangrove leaf and ethanolic extract respectively. The results of phytochemical screening of Avicennia marina leaves extract showed the existence of alkaloids, tannins, saponins, flavone and glycosides. 2-Propenoic acid, 3-phenyl- was the major compound of Avicennia marina. The results of non-significant lack of fit tests, and F value (14.62) indicated that the model was sufficiently accurate. In addition, the coefficient of variations (16.8%) showed an acceptable reproducibility. Copyright © 2017 Elsevier Ltd. All rights reserved.

Enterococci in foods--a conundrum for food safety.

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Franz, Charles M A P; Stiles, Michael E; Schleifer, Karl Heinz; Holzapfel, Wilhelm H

2003-12-01

Enterococci form part of the lactic acid bacteria (LAB) of importance in foods. They can spoil processed meats but they are on the other hand important for ripening and aroma development of certain traditional cheeses and sausages, especially those produced in the Mediterranean area. Enterococci are also used as human probiotics. However, they are important nosocomial pathogens that cause bacteraemia, endocarditis and other infections. Some strains are resistant to many antibiotics, but antibiotic resistance alone cannot explain the virulence of some of these bacteria. Virulence factors such as adhesins, invasins and haemolysin have been described. The role of enterococci in disease has raised questions on their safety for use in foods or as probiotics. Studies on the incidence of virulence traits among enterococcal strains isolated from food showed that some harbour virulence traits and generally, Enterococcus faecalis harbours more of them than Enterococcus faecium. Regulations in Europe stipulate that safety of probiotic or starter strains is the responsibility of the producer; therefore, each strain intended for such use should be carefully evaluated. For numerous questions, immediate answers are not fully available. It is therefore suggested that when considering an Enterococcus strain for use as a starter or probiotic culture, it is imperative that each particular strain should be carefully evaluated for the presence of all known virulence factors. Ideally, such strains should harbour no virulence determinants and should be sensitive to clinically relevant antibiotics. In general, E. faecium appears to pose a lower risk for use in foods, because these strains generally harbour fewer recognised virulence determinants than E. faecalis. Generally, the incidence of such virulence determinants among E. faecium strains is low, as compared to E. faecalis strains, probably as a result of the presence of pheromone-responsive plasmids.

Heat resistance of thermoduric enterococci isolated from milk.

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McAuley, Catherine M; Gobius, Kari S; Britz, Margaret L; Craven, Heather M

2012-03-15

Enterococci are reported to survive pasteurisation but the extent of their survival is unclear. Sixty-one thermoduric enterococci isolates were selected from laboratory pasteurised milk obtained from silos in six dairy factories. The isolates were screened to determine log(10) reductions incurred after pasteurisation (63°C/30 min) and ranked from highest to lowest log(10) reduction. Two isolates each of Enterococcus faecalis, Enterococcus faecium, Enterococcus durans and Enterococcus hirae, exhibiting the median and the greatest heat resistance, as well as E. faecalis ATCC 19433, were selected for further heat resistance determinations using an immersed coil apparatus. D values were calculated from survival curves plotted from viable counts obtained after heating isolates in Brain Heart Infusion Broth at 63, 69, 72, 75 and 78°C followed by rapid cooling. At 72°C, the temperature employed for High Temperature Short Time (HTST) pasteurisation (72°C/15s), the D values extended from 0.3 min to 5.1 min, depending on the isolate and species. These data were used to calculate z values, which ranged from 5.0 to 9.8°C. The most heat sensitive isolates were E. faecalis (z values 5.0, 5.7 and 7.5°C), while the most heat resistant isolates were E. durans (z values 8.7 and 8.8°C), E. faecium (z value 9.0°C) and E. hirae (z values 8.5 and 9.8°C). The data show that heat resistance in enterococci is highly variable. Copyright © 2011 Elsevier B.V. All rights reserved.

Bacteriocin producers from traditional food products

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Thonart P.

2007-01-01

Full Text Available A total of 220 strains of LAB isolated from 32 samples of traditional fermented food from Senegal were screened for bacteriocin production. Two bacteriocin producers, Lactococcus lactis subsp. lactis and Enterococcus faecium, were identified from 12 bacteriocin-producing isolates on the basis of phenotypic analyses and 16S rDNA sequence. Both bacteriocins produced by new isolates show antimicrobial activity against Listeria monocytogenes and Bacillus coagulans whereas only that produced by Lactococcus lactis has an activity against Bacillus cereus. Bacteriocin-producing Lactococcus lactis strains were found in a variety of traditional foods indicating a high potential of growth of this strain in variable ecological complex environment. Partial 16S rDNA of the two bacteriocin producers obtained in this study has been registered to Genbank databases under the accession number AY971748 for Lactococcus lactis subsp. lactis (named CWBI-B1410 and AY971749 for Enterococcus faecium (named CWBI-B1411. The new bacteriocin-producing Lactococcus lactis subsp. lactis strain has been selected for identification and application of the bacteriocin to food preservation.

Molecular Characterization of Glycopeptide-Resistant Enterococci from Hospitals of the Picardy Region (France

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M. Biendo

2010-01-01

Full Text Available We studied 138 glycopeptide-resistant enterococci (GRE strains, consisting of 131 glycopeptide-resistant Enterococcus faecium (GREfm and 7 glycopeptide-resistant Enterococcus faecalis (GREfs. The GREfm strains were resistant to penicillin, ampicillin, vancomycin, and teicoplanin, while the GREfs strains were only resistant to vancomycin and teicoplanin. The van A gene was the only glycopeptide determinant present in all GRE isolates investigated. Genes coding for Hyl and Hyl+ Esp were detected in 39 (29.8% and 92 (70.2% of the 131 GREfm isolates, respectively. Three of the 7 GREfs were positive for gelE+asa 1 genes, 3 for gel E gene, and 1 for asa 1 gene. The genetic relationship between the 138 GRE was analyzed by pulsed-field gel electrophoresis (PFGE and multilocus sequence typing (MLST. GREfm isolates were clustered in a single genogroup (pulsotype A, and GREfs were clustered in six genogroups (pulsotypes B-G. Among the isolates investigated by MLST, only 18 PCR products were sequenced (12 E. faecium and 6 E. faecalis, and 9 sequence types (STs were identified.

In vitro activity of tigecycline and comparator agents against a global collection of Gram-negative and Gram-positive organisms: tigecycline Evaluation and Surveillance Trial 2004 to 2007.

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Garrison, Mark W; Mutters, Reinier; Dowzicky, Michael J

2009-11-01

The Tigecycline Evaluation and Surveillance Trial began in 2004 to monitor the in vitro activity of tigecycline and comparator agents against a global collection of Gram-negative and Gram-positive pathogens. Against Gram negatives (n = 63 699), tigecycline MIC(90)'s ranged from 0.25 to 2 mg/L for Escherichia coli, Haemophilus influenzae, Acinetobacter baumannii, Klebsiella oxytoca, Enterobacter cloacae, Klebsiella pneumoniae, and Serratia marcescens (but was > or =32 for Pseudomonas aeruginosa). Against Gram-positive organisms (n = 32 218), tigecycline MIC(90)'s were between 0.06 and 0.25 mg/L for Streptococcus pneumoniae, Enterococcus faecium, Streptococcus agalactiae, Staphylococcus aureus, and Enterococcus faecalis. The in vitro activity of tigecycline was maintained against resistant phenotypes, including multidrug-resistant A. baumannii (9.2% of isolates), extended-spectrum beta-lactamase-producing E. coli (7.0%) and K. pneumoniae (14.0%), beta-lactamase-producing H. influenzae (22.2%), methicillin-resistant S. aureus (44.5%), vancomycin-resistant E. faecium (45.9%) and E. faecalis (2.8%), and penicillin-resistant S. pneumoniae (13.8%). Tigecycline represents a welcome addition to the armamentarium against difficult to treat organisms.

Isolation of vancomycin resistant Enterococcus faecium from food

DEFF Research Database (Denmark)

Wegener, Henrik Caspar; Madsen, Mogens; Nielsen, Niels

1997-01-01

was not detected in 124 samples of pork and 128 samples of beef from retail outlets by the direct plating method. An additional enrichment step in nutrient broth supplemented with vancomycin enhanced the detection rate of VREF by approximately three times compared to the direct plating method when investigating...... the same 160 samples of broilers by the two methods. The implications and public health aspects of VREF in food is discussed....

Daptomycin-Vancomycin–Resistant Enterococcus faecium Native Valve Endocarditis

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Khandakar Hussain MD

2016-09-01

Full Text Available Multidrug-resistant enterococcal nosocomial invasive infections are a rising concern faced by the medical community. Not many options are available to treat these highly virulent organisms. Risk factors for developing these highly resistant organisms include prolonged hospital stay, previous antibiotic use, and immunosuppression. In this article, we report a case of daptomycin-resistant enterococcal native infective endocarditis treated with off-label use of quinupristin-dalfopristin.

Plantas transgênicas resistentes a insetos e organismos não-alvo: predadores, parasitóides e polinizadores - doi: 10.5102/ucs.v4i1.23

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Marina Regina Frizzas

2008-04-01

Full Text Available Plantas geneticamente modificadas resistentes aos insetos oferecem benefícios à agricultura moderna. No entanto, esta tecnologia pode afetar o controle biológico natural e a biodiversidade por meio de efeitos diretos e indiretos das plantas transgênicas sobre o valor adaptativo e comportamental de predadores, parasitóides, polinizadores e outros artrópodes não-alvo. Neste artigo, são discutidos os impactos ou os efeitos potenciais de plantas transgênicas resistentes a insetos sobre organismos não-alvo, com ênfase em artrópodes predadores, parasitóides e polinizadores, e os principais estudos com plantas transgênicas resistentes a insetos, publicados nos últimos dez anos.

Effect of whey fermented by Enterococcus faeciumin consortium with Veilonella parvulaon ruminal bacteria in vitro

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Higor Fábio Carvalho Bezerra

2014-05-01

Full Text Available The objective of this research was to evaluate the effect of whey fermented by Enterococus faecium in consortium with Veilonella parvula in vitro on ruminal microorganisms in different substrates, with or without monensin. The first experiment was carried out in a completely randomized design, in a 6 × 3 factorial arrangement (six substrates × three whey levels with two replicates. In experiment two, a 2 × 3 × 4 factorial arrangement (with and without monensin, three foods and four levels of fermented whey was used, in a randomized design with four replicates, totaling 24 treatments. There was no interaction among the wheys and the substrates in the variable for pectin, starch, and carboxymethyl cellulose. There was a greater growth of amylolytic and pectinolytic microorganisms and a lower growth of proteolytic and cellulolytic microorganisms. A significant effect of optical density was found in the media without substrate and that containing trypticase and glucose due to the addition of fermented whey. There was interaction for the pH at 24 hours among whey, food and monensin. For ammonia at 24 hours there was effect for food, whey and monensin, and interaction among factors. For microbial protein at 24 hours, there was effect for food, whey, monensin and no interaction among sources of variation. The use of whey fermented by bacteria Enterococcus faeciumand Veilonella parvula improves microbial protein synthesis by ruminal bacteria in media containing different energy sources. The combination of fermented whey and monensin shows variable results in relation to microbial growth.

The cfr and cfr-like multiple resistance genes

DEFF Research Database (Denmark)

Vester, Birte

2018-01-01

. The cfr gene is found in various bacteria in many geographical locations and placed on plasmids or associated with transposons. Cfr-related genes providing similar resistance have been identified in Bacillales, and now also in the pathogens Clostridium difficile and Enterococcus faecium. In addition......, the presence of the cfr gene has been detected in harbours and food markets....

Comprobaciones resistentes de elementos constructivos de tierra

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Estrada, Enrique

1986-11-01

Full Text Available This work has the purpose to compare, by means of different tests on adobe bricks and masonry, the obtained resistant properties and those of other similar works carried out in countries having a wide tradition and knowledge about earth as construction material. Elements (adobe bricks and blocks have been tested to compression and bending, and masonry made of those elements to compression and diagonal compression.El presente trabajo pretende comparar, por medio de distintos ensayos sobre elementos y fábricas de mampostería de tierra, las propiedades resistentes obtenidas con las de otros trabajos similares realizados en países con dilatada tradición y conocimiento de la tierra como material de construcción. Se han ensayado elementos (adobes y bloques a compresión y flexotracción y fábricas formadas por conjuntos de los mismos a compresión y a compresión diagonal.

Dogs leaving the ICU carry a very large multi-drug resistant enterococcal population with capacity for biofilm formation and horizontal gene transfer.

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Anuradha Ghosh

Full Text Available The enterococcal community from feces of seven dogs treated with antibiotics for 2-9 days in the veterinary intensive care unit (ICU was characterized. Both, culture-based approach and culture-independent 16S rDNA amplicon 454 pyrosequencing, revealed an abnormally large enterococcal community: 1.4±0.8×10(8 CFU gram(-1 of feces and 48.9±11.5% of the total 16,228 sequences, respectively. The diversity of the overall microbial community was very low which likely reflects a high selective antibiotic pressure. The enterococcal diversity based on 210 isolates was also low as represented by Enterococcus faecium (54.6% and Enterococcus faecalis (45.4%. E. faecium was frequently resistant to enrofloxacin (97.3%, ampicillin (96.5%, tetracycline (84.1%, doxycycline (60.2%, erythromycin (53.1%, gentamicin (48.7%, streptomycin (42.5%, and nitrofurantoin (26.5%. In E. faecalis, resistance was common to tetracycline (59.6%, erythromycin (56.4%, doxycycline (53.2%, and enrofloxacin (31.9%. No resistance was detected to vancomycin, tigecycline, linezolid, and quinupristin/dalfopristin in either species. Many isolates carried virulence traits including gelatinase, aggregation substance, cytolysin, and enterococcal surface protein. All E. faecalis strains were biofilm formers in vitro and this phenotype correlated with the presence of gelE and/or esp. In vitro intra-species conjugation assays demonstrated that E. faecium were capable of transferring tetracycline, doxycycline, streptomycin, gentamicin, and erythromycin resistance traits to human clinical strains. Multi-locus variable number tandem repeat analysis (MLVA and pulsed-field gel electrophoresis (PFGE of E. faecium strains showed very low genotypic diversity. Interestingly, three E. faecium clones were shared among four dogs suggesting their nosocomial origin. Furthermore, multi-locus sequence typing (MLST of nine representative MLVA types revealed that six sequence types (STs originating from five

Influence of a probiotic soy product on fecal microbiota and its association with cardiovascular risk factors in an animal model

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Cavallini Daniela CU

2011-07-01

Full Text Available Abstract Background Previous work showed that daily ingestion of an aqueous soy extract fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus 416, supplemented or not with isoflavones, reduced the total cholesterol and non-HDL-cholesterol levels, increased the high-density lipoprotein (HDL concentration and inhibited the raising of autoantibody against oxidized low-density lipoprotein (ox-LDL Ab and the development of atherosclerotic lesions. Objective The aim of this study was to characterize the fecal microbiota in order to investigate the possible correlation between fecal microbiota, serum lipid parameters and atherosclerotic lesion development in rabbits with induced hypercholesterolemia, that ingested the aqueous soy extract fermented with Enterococcus faecium CRL 183 and Lactobacillus helveticus 416. Methods The rabbits were randomly allocated to five experimental groups (n = 6: control (C, hypercholesterolemic (H, hypercholesterolemic plus unfermented soy product (HUF, hypercholesterolemic plus fermented soy product (HF and hypercholesterolemic plus isoflavone-supplemented fermented soy product (HIF. Lipid parameters and microbiota composition were analyzed on days 0 and 60 of the treatment and the atherosclerotic lesions were quantified at the end of the experiment. The fecal microbiota was characterized by enumerating the Lactobacillus spp., Bifidobacterium spp., Enterococcus spp., Enterobacteria and Clostridium spp. populations. Results After 60 days of the experiment, intake of the probiotic soy product was correlated with significant increases (P Lactobacillus spp., Bifidobacterium spp. and Enterococcus spp. and a decrease in the Enterobacteria population. A strong correlation was observed between microbiota composition and lipid profile. Populations of Enterococcus spp., Lactobacillus spp. and Bifidobacterium spp. were negatively correlated with total cholesterol, non-HDL-cholesterol, autoantibodies against

Estudio metabólico y molecular de cultivos bacterianos degradadores de hidrocarburos aromáticos policíclicos (PAH) y resistentes a metales pesados

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Cecotti, Martina; Morelli, Irma Susana; Coppotelli, Bibiana

2015-01-01

La contaminación mixta con PAH y metales pesados conlleva dificultades debido a la potencial toxicidad del metal, limitando la supervivencia solo a los microorganismos que toleren ambos contaminantes. El estudio de cepas degradadoras de PAH y resistentes a metales pesados promete proporcionar herramientas claves para el proceso de biorremediación. Este trabajo tuvo como objetivos la selección, identificación y caracterización de cepas degradadoras de PAH y resistentes a metales pesados aislad...

LACTIC ACID BACTERIA FLORA OF KONYA KUFLU CHEESE: A TRADITIONAL CHEESE FROM KONYA PROVINCE IN TURKEY

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Ziba Guley

2014-12-01

Full Text Available The aim of this study was to characterize the lactic acid bacteria flora of mature Konya Kuflu cheese. Konya Kuflu cheese is a traditional blue cheese which is produced from raw milk without starter culture addition and mould growth occurs in uncontrolled conditions during its ripening. Lactic acid bacteria (LAB isolated from 9 mature Konya Kuflu cheese samples were investigated using a combination of conventional biochemical tests, API test kits, and molecular approaches. For some isolates, different results were obtained according to the identification technique. The overall LAB profile of Konya Kuflu cheese samples revealed that Lactobacillus brevis, Lactobacillus paracasei/Lactobacillus casei, Lactobacillus plantarum, Enterococcus faecium, and Enterococcus faecalis are the predominant species. In addition, 1 Pediococcus parvulus and 1 Enterococcus durans were also identified.

Impact of probiotic drugs, based on Enterobacter faecium autostrains, on human intestinal microflora in confined habitat

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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

Characterization of Two Metal Binding Lipoproteins as Vaccine Candidates for Enterococcal Infections.

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Romero-Saavedra, Felipe; Laverde, Diana; Budin-Verneuil, Aurélie; Muller, Cécile; Bernay, Benoit; Benachour, Abdellah; Hartke, Axel; Huebner, Johannes

2015-01-01

Enterococcus faecium and faecalis are Gram-positive opportunistic pathogens that have become leading causes of nosocomial infections over the last decades. Especially multidrug resistant enterococci have become a challenging clinical problem worldwide. Therefore, new treatment options are needed and the identification of alternative targets for vaccine development has emerged as a feasible alternative to fight the infections caused by these pathogens. We extrapolate the transcriptomic data from a mice peritonitis infection model in E. faecalis to identify putative up-regulated surface proteins under infection conditions in E. faecium. After the bionformatic analyses two metal binding lipoproteins were identified to have a high homology (>72%) between the two species, the manganese ABC transporter substrate-binding lipoprotein (PsaAfm,) and the zinc ABC transporter substrate-binding lipoprotein (AdcAfm). These candidate lipoproteins were overexpressed in Escherichia coli and purified. The recombinant proteins were used to produce rabbit polyclonal antibodies that were able to induce specific opsonic antibodies that mediated killing of the homologous strain E. faecium E155 as well as clinical strains E. faecium E1162, Enterococcus faecalis 12030, type 2 and type 5. Mice were passively immunized with the antibodies raised against recombinant lipoproteins, showing significant reduction of colony counts in mice livers after the bacterial challenge and demonstrating the efficacy of these metal binding lipoproteins as promising vaccine candidates to treat infections caused by these enterococcal pathogens. Overall, our results demonstrate that these two metal binding lipoproteins elicited specific, opsonic and protective antibodies, with an extensive cross-reactivity and serotype-independent coverage among these two important nocosomial pathogens. Pointing these two protein antigens as promising immunogens, that can be used as single components or as carrier proteins

Staphylococcus aureus resistente a meticilina asociado a la comunidad: aspectos epidemiológicos y moleculares

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Daniel Angel Luján Roca

2013-01-01

Full Text Available El Staphylococcus aureus resistente a meticilina asociado a la comunidad (SARM-AC está ampliamente diseminado en el mundo. Es epidémico en algunos países y posee dos marcadores moleculares característicos: el SCCmec IV y la leucocidina de Panton-Valentine, ambos escasamente encontrados en el SARM asociado a la asistencia médica.

Evaluación de estructuras de muros resistentes

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Lewicki, Bohdan

1988-12-01

Full Text Available The author of this article, who is one of the main International personalities in the field of the structural engineering, point out the importance of intuition as a component of the creative capacity of the engineer, as well as its necessity within de evaluation process of structures. The article includes also some Indications about the general principles on reliability of masonry structures.

El autor del presente artículo, una de las máximas autoridades mundiales en el campo de la Ingeniería estructural, señala la importancia de la intuición como componente de la capacidad creadora del ingeniero y su necesidad en el proceso de evaluación de las estructuras. En el artículo se dan también unas indicaciones referentes a principios generales sobre fiabilidad de las estructuras de muros resistentes.

Enterococcus faecalis infective endocarditis

DEFF Research Database (Denmark)

Dahl, Anders; Bruun, Niels Eske

2013-01-01

Enterococcus faecalis infective endocarditis (IE) is a disease of increasing importance, with more patients infected, increasing frequency of health-care associated infections and increasing incidence of antimicrobial resistances. The typical clinical presentation is a subacute course with fever...... or ceftriaxone. E. faecalis infective endocarditis continues to be a very serious disease with considerable percentages of high-level gentamicin resistant strains and in-hospital mortality around 20%. Strategies to prevent E. faecalis IE, improve diagnostics, optimize treatment and reduce morbidity...

Manejo de capim pé-de-galinha em lavouras de soja transgênica resistente ao glifosato

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André da Rosa Ulguim

2013-01-01

Full Text Available O objetivo deste trabalho foi avaliar a resistência de capim pé-de-galinha (Eleusine indica ao glifosato, em lavouras de soja transgênica; avaliar o efeito de aplicações de glifosato em diferentes estádios de desenvolvimento; identificar práticas agronômicas associadas à seleção de biótipos resistentes; e avaliar a eficiência dos herbicidas cletodim, fluazifope-P-butílico, clomazona, glufosinato de amônio e glifosato nas plantas resistentes. Plantas escapes ao tratamento com glifosato foram coletadas em 24 propriedades, no Rio Grande do Sul. As plantas foram cultivadas em casa de vegetação, tendo-se avaliado a sua resistência ao glifosato. Os acessos resistentes foram selecionados e avaliados quanto ao efeito da aplicação do glifosato em diferentes estádios de crescimento e quanto à sensibilidade aos herbicidas. Foi aplicado um questionário aos produtores para identificação das práticas agronômicas associadas às falhas no controle. O controle de E. indica pelo glifosato é mais efetivo com a aplicação em estádios iniciais de desenvolvimento. Práticas agronômicas, como uso contínuo de baixas doses do herbicida, aplicação em estádios de desenvolvimento avançados das plantas daninhas (mais de um afilho e a ausência de rotação de culturas foram relacionadas às falhas de controle observadas. Os herbicidas cletodim, fluazifope-P-butílico e glufosinato de amônio são alternativas eficientes para o controle de E. indica.

Electroconvulsive therapy in treatment-resistant mania: case reports A Eletroconvulsoterapia no tratamento da mania resistente: relatos de casos

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Marcia Britto de Macedo Soares

2002-02-01

Full Text Available Electroconvulsive therapy is known to be effective in the treatment of mood disorders, more specifically for depression and mania. Although a large body of evidence confirms the efficacy of electroconvulsive therapy in the treatment of mania, few prospective studies have been done to assess its effectiveness in treatment-resistant manic episodes. These case reports describe the initial results of a study that is being conducted to evaluate the efficacy of Electroconvulsive therapy among treatment-resistant bipolar patients. METHODS: Three manic patients (according to DSM-IV criteria who were considered treatment-resistant underwent a series of 12 bilateral Electroconvulsive therapy sessions. Before the treatment and then weekly, they were evaluated with the following rating scales: Young Mania Rating Scale, Hamilton Rating Scale for Depression, Brief Psychiatric Rating Scale, and Clinical Global Impressions-Bipolar Version. RESULTS: The 3 patients showed a satisfactory response to Electroconvulsive therapy, although some differences in the course of response were observed. CONCLUSION: These case reports suggest that Electroconvulsive therapy needs further evaluation for the treatment of resistant bipolar patients.A Eletroconvulsoterapia é uma alternativa reconhecidamente eficaz no tratamento dos transtornos do humor. Embora vários estudos tenham confirmado a eficácia desta modalidade terapêutica no tratamento da mania aguda, poucos estudos foram realizados em pacientes maníacos resistentes à farmacoterapia. Esses relatos de casos descrevem resultados preliminares de um projeto de pesquisa que tem por objetivo avaliar a eficácia da Eletroconvulsoterapia no tratamento de transtornos bipolares resistentes. MÉTODOS: Três pacientes com diagnóstico de mania (de acordo com os critérios do DSM-IV, considerados resistentes ao tratamento medicamentoso, foram submetidos a 12 aplicações bilaterais de Eletroconvulsoterapia. Antes do tratamento e

New Insight into Biofilm Formation Ability, the Presence of Virulence Genes and Probiotic Potential of Enterococcus sp. Dairy Isolates

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Nikola Popović

2018-01-01

Full Text Available Enterococci have controversial status due to their emerging role in nosocomial infections and transmission of antibiotic resistance genes, while some enterococci strains are used as probiotics for humans and animals and starter cultures in dairy industry. In order to improve our understanding of factors involved in the safe use of enterococci as potential probiotics, the antibiotic susceptibility, virulence and probiotic traits of 75 dairy enterococci isolates belonging to Enterococcus durans (50, En. faecium (15, En. faecalis (6, En. italicus (3, and En. hirae (1 were evaluated. The results revealed that ciprofloxacin resistance and biofilm formation are correlated with isolates originated from Golija mountain (Serbia, while gelatinase activity was more common in isolates from Prigorje region (Croatia, pointing to uncontrolled use of antibiotics and anthropogenic impact on dairy products' microbiota in these regions. The virulence genes were sporadically present in 13 selected dairy enterococci isolates. Interestingly, biofilm formation was correlated with higher ability of strains to reduce the adhesion of E. coli and Salmonella Enteritidis to HT29-MTX cells. To our knowledge this is the first study reporting the presence of the esp gene (previously correlated with pathogenesis in dairy enterococci isolates, mostly associated with the genes involved in adhesion property. Hence, the results of this study revealed that the virulence genes are sporadically present in dairy isolates and more correlated to adhesion properties and biofilm formation, implicating their role in gut colonization rather than to the virulence traits.

TERAPIA FOTODINÂMICA COM AZUL DE METILENO SOBRE CEPA DE Staphylococcus aureus RESISTENTE À METICILINA

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Mirian Alves Freitas

2017-01-01

Full Text Available S. aureus é o agente etiológico de maior importância associado às infecções adquiridas tanto em âmbito comunitário ou hospitalar, devido a sua capacidade de desenvolver resistência às terapias convencionais. A Terapia Fotodinâmica (TFD surge como alternativa a ser utilizada no controle de cepas resistentes aos antibioticos. O objetivo do presente estudo é avaliar os efeitos da TFD com Azul de Metileno (AM sobre cepas de S. aureus resistente à meticilina (MRSA. As amostras foram diluídas em PBS estéril de acordo com a escala 0,5 de MacFarland. Os grupos foram compostos com diferentes concentrações de AM, incubados no escuro durante 15 minutos e irradiados por LED Biopdi/Irrad-Led5 em 660nm com fluência de 10 J/cm². Posteriormente, foram semeadas e incubadas à 37ºC por 24 horas. A contagem de Unidades Formadoras de Colônias (UFCs demonstrou que a TFD foi eficaz na menor concentração testada de AM sobre cepas de MRSA.

Molecular characterization, technological properties and safety aspects of enterococci from 'Hussuwa', an African fermented sorghum product.

Science.gov (United States)

Yousif, N M K; Dawyndt, P; Abriouel, H; Wijaya, A; Schillinger, U; Vancanneyt, M; Swings, J; Dirar, H A; Holzapfel, W H; Franz, C M A P

2005-01-01

To identify enterococci from Hussuwa, a Sudanese fermented sorghum product, and determine their technological properties and safety for possible inclusion in a starter culture preparation. Twenty-two Enterococcus isolates from Hussuwa were identified as Enterococcus faecium by using phenotypic and genotypic tests such as 16S rDNA gene sequencing, RAPD-PCR and restriction fragment length polymorphism of the 16S/23S intergenic spacer region fingerprinting. Genotyping revealed that strains were not clonally related and exhibited a considerable degree of genomic diversity. Some strains possessed useful technological properties such as production of bacteriocins and H2O2 or utilization of raffinose and stachyose. None produced alpha-amylase or tannase. A safety investigation revealed that all strains were susceptible to the antibiotics ampicillin, gentamicin, chloramphenicol, tetracycline and streptomycin, but some were resistant to ciprofloxacin, erythromycin, penicillin and vancomycin. Production of biogenic amines or presence of genes encoding virulence determinants occurred in some strains. Enterococcus faecium strains are associated with fermentation of Sudanese Hussuwa. Some strains exhibited useful technological properties such as production of antimicrobial agents and fermentation of indigestible sugars, which may aid in stabilizing and improving the digestibility of the product respectively. Enterococci were shown to play a role in the fermentation of African foods. While beneficial properties of these bacteria are indicated, their presence in this food may also imply a hygienic risk as a result of antimicrobial resistances or presence of virulence determinants.

Polyhexamethylene guanidine hydrochloride shows bactericidal advantages over chlorhexidine digluconate against ESKAPE bacteria.

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Zhou, Zhongxin; Wei, Dafu; Lu, Yanhua

2015-01-01

More information regarding the bactericidal properties of polyhexamethylene guanidine hydrochloride (PHMG) against clinically important antibiotic-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens needs to be provided for its uses in infection control. The bactericidal properties of PHMG and chlorhexidine digluconate (CHG) were compared based on their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations, and time-course-killing curves against clinically important antibiotic-susceptible and antibiotic-resistant ESKAPE pathogens. Results showed that PHMG exhibited significantly higher bactericidal activities against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and ceftazidime-resistant Enterobacter spp. than CHG. A slight bactericidal advantage over CHG was obtained against vancomycin-resistant Enterococcus faecium, ciprofloxacin- and levofloxacin-resistant Acinetobacter spp., and multidrug-resistant Pseudomonas aeruginosa. In previous reports, PHMG had higher antimicrobial activity against almost all tested Gram-negative bacteria and several Gram-positive bacteria than CHG using MIC test. These studies support the further development of covalently bound PHMG in sterile-surface materials and the incorporation of PHMG in novel disinfectant formulas. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

ANTIBIOTIC RESISTANCE IN LACTIC ACID BACTERIA ISOLATED FROM FERMENTED DAIRY PRODUCTS AND BOZA

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Gamze Başbülbül

2015-06-01

Full Text Available In this study, the resistance of 83 strains of lactic acid bacteria isolated from Turkish cheese, yogurt, kefir and boza samples to 6 antibiotics (gentamicin, tetracycline, chloramphenicol, erythromycin, vancomycin and ciprofloxacin was evaluated. The 83 isolates were identified by 16S rRNA gene sequencing and according to BLAST comparisons with sequences in the data banks, those strains showing the highest similarities with the isolates were Enterococcus faecium (10, Lactococcus lactis subsp. Lactis (10, Lactobacillus fermentum (6, Lactobacillus plantarum (6, Lactobacillus coryniformis (7, Lactobacillus casei (13, Leuconostoc mesenteroides (14, Pediococcus pentosaceus (10, Weisella confusa (7. Antimicrobial resistance of strains to 6 antibiotics was determined using the agar dilution method. The antibiotic resistance among all the isolates was detected against chloramphenicol (31,3 % of the isolates, tetracycline (30,1 %, erythromycin (2,4 %, ciprofloxacin (2,41%, vancomycin (73,5 %, intrinsic resistance. Overall 19,3 % of the isolates showed resistance against multiple antibiotics. Antibiotic resistance genes were studied by PCR and the following genes were detected; tet(M gene in Lactobacillus fermentum (1, Lactobacillus plantarum (1, Pediococcus pentosaceus (5, Enterococcus faecium (2, Weisella confusa (4 and the vancomycin resistance gene van(A in one Weisella confusa strain.

Effect of co-culture with enterocinogenic E. faecium on L. monocytogenes key virulence gene expression

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Eleftherios H. Drosinos

2016-08-01

Full Text Available The aim of the present study was to assess the expression of key virulence genes during co-culture of L. monocytogenes with a bacteriocinogenic E. faecium strain in liquid growth medium. For that purpose, BHI broth was inoculated with 7 log CFU·mL–1 L. monocytogenes and 4, 5 or 6 log CFU·mL–1 E. faecium. Sampling took place after 8 and 24 h of incubation, corresponding to the maximum and minimum of enterocin production, respectively. The RNA was extracted, stabilized and expression of prfA, sigB, hly, plcA, plcB, inlA, inlB, inlC and inlJ, was assessed by RT-qPCR. Most of the genes were downregulated during co-culture at 5 °C. Moreover, a statistically significant effect of the inoculum level was evident in most of the cases. On the contrary, no effect on the transcription level of most of the genes was observed during co-culture at 37 °C.

Antimicrobial resistance and virulence profile of enterococci isolated from poultry and cattle sources in Nigeria.

Science.gov (United States)

Ngbede, Emmanuel Ochefije; Raji, Mashood Abiola; Kwanashie, Clara Nna; Kwaga, Jacob Kwada Paghi

2017-03-01

This study investigated the occurrence, antimicrobial resistance and virulence of Enterococcus from poultry and cattle farms. Three hundred and ninety samples: cloacal/rectal swabs (n = 260) and manure (n = 130] were processed for recovery of Enterococcus species. Standard bacteriological methods were used to isolate, identify and characterize Enterococcus species for antimicrobial susceptibility and expression of virulence traits. Detection of antibiotic resistance and virulence genes was carried out by polymerase chain reaction. Enterococcus was recovered from 167 (42.8%) of the 390 samples tested with a predominance of Enterococcus faecium (27.7%). Other species detected were Enterococcus gallinarum, Enterococcus faecalis, Enterococcus hirae, Enterococcus raffinosus, Enterococcus avium, Enterococcus casseliflavus, Enterococcus mundtii and Enterococcus durans. All the isolates tested were susceptible to vancomycin, but resistance to tetracycline, erythromycin, ampicillin and gentamicin was also observed among 61.0, 61.0, 45.1 and 32.7% of the isolates, respectively. Sixty (53.1%) of the isolates were multidrug resistant presenting as 24 different resistance patterns with resistance to gentamicin-erythromycin-streptomycin-tetracycline (CN-ERY-STR-TET) being the most common (n = 11) pattern. In addition to expression of virulence traits (haemolysin, gelatinase, biofilm production), antibiotic resistance (tetK, tetL, tetM, tetO and ermB) and virulence (asa1, gelE, cylA) genes were detected among the isolates. Also, in vitro transfer of resistance determinants was observed among 75% of the isolates tested. Our data revealed poultry, cattle and manure in this area are hosts to varying Enterococcus species harbouring virulence and resistance determinants that can be transferred to other organisms and also are important for causing nosocomial infection.

Manejo de Conyza bonariensis resistente ao herbicida glyphosate Management of Glyphosate-resistant Conyza bonariensis

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J.M. Paula

2011-03-01

Full Text Available C. bonariensis (Conyza bonariensis é uma planta daninha da família Asteraceae, amplamente distribuída no Brasil, com presença marcante nos Estados do Rio Grande do Sul e do Paraná. Biótipos de C. bonariensis resistentes ao glyphosate foram identificados nos Estados do Rio Grande do Sul, Paraná e São Paulo. O objetivo deste trabalho foi avaliar o efeito de diferentes manejos de inverno e na pré-semeadura da soja sobre a população de plantas de C. bonariensis resistente ao herbicida glyphosate. Os resultados evidenciaram que a população de C. bonariensis é maior em áreas mantidas sem cultivo (pousio do que naquelas áreas cultivadas com trigo ou aveia-preta durante o inverno. Observou-se que o trigo e a aveia-preta exercem efeito supressor sobre a população de C. bonariensis, proporcionando maior facilidade de controle com herbicida na pré-semeadura da cultura usada em sucessão. O controle de C. bonariensis resistente ao herbicida glyphosate foi satisfatório quando se utilizaram herbicidas pós-emergentes na cultura do trigo e glyphosate + 2,4-D ou glyphosate + diuron + paraquat na pré-semeadura da soja.Horseweed (Conyza bonariensis, which belongs to the Asteraceae family, is a weed species widely spread in Brazil. Horseweed biotypes resistant to glyphosate, the main herbicide used in Roundup Ready soybean fields, were identified in the states of Rio Grande do Sul and Parana. The aim of this study was to evaluate the effect of different winter and pre-sowing management techniques on soybean plant population of C. bonariensis resistant to glyphosate. The results showed that the population of C. bonariensis is larger in areas maintained fallow than in areas planted with wheat or oats during the winter. Wheat and oats were found to exert a suppressive effect on the population of C. bonariensis, providing greater ease of control with herbicide before seeding in the culture used in succession. The control of glyphosate-resistant C

Diseño de dos metodologías moleculares para la rápida identificación de aislamientos de Staphylococcus aureus resistente a meticilina asociados a la comunidad en Colombia

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Javier Antonio Escobar

2012-06-01

Full Text Available Introducción. Los aislamientos de Staphylococcus aureus resistente a la meticilina asociado a la comunidad (SARM-AC, están aumentando la frecuencia de infecciones en personas sanas de la comunidad y en pacientes hospitalizados. En Colombia y en la región andina estos aislamientos tienen un componente genético relacionado con el clon pandémico USA300. Objetivo. Diseñar y estandarizar dos metodologías para la diferenciación rápida de aislamientos colombianos de S. aureus resistente a la meticilina asociado a la comunidad de los asociados al hospital (SARM-AH. Materiales y métodos. Se estandarizaron dos metodologías moleculares para la identificación de aislamientos de S. aureus resistente a la meticilina asociado a la comunidad. La primera se basa en la digestión diferencial con tres enzimas de restricción de los genes cinasa de carbamato (arcC y cinasa de guanilato (gmk para los tipos de secuencia 5 (ST5 y 8 (ST8, correspondientes a aislamientos de S. aureus resistente a la meticilina asociado al hospital y asociado a la comunidad, respectivamente. La segunda se basa en la amplificación por reacción en cadena de la polimerasa de cinco factores de virulencia que se encuentran de manera diferencial en estos aislamientos. Las dos metodologías fueron validadas en 237 aislamientos clínicos de S. aureus resistente a la meticilina. Resultados. Con la primera metodología se identificaron el 100 % y 93,2 % de los aislamientos de S. aureus resistente a la meticilina asociado a la comunidad y asociado al hospital, respectivamente. Con la segunda metodología se identificaron correctamente los dos tipos de aislamientos. Conclusiones. Estas dos metodologías son una buena alternativa en términos de ahorro en tiempo y dinero comparadas con otras técnicas, como la electroforesis en campo pulsado y la tipificación de secuencias multilocus para la rápida identificación de aislamientos de S. aureus resistente a la meticilina asociado a la

Antimicrobial resistance and virulence genes in enterococci from wild game meat in Spain.

Science.gov (United States)

Guerrero-Ramos, Emilia; Cordero, Jorge; Molina-González, Diana; Poeta, Patrícia; Igrejas, Gilberto; Alonso-Calleja, Carlos; Capita, Rosa

2016-02-01

A total of 55 enterococci (45 Enterococcus faecium, 7 Enterococcus faecalis, and three Enterococcus durans) isolated from the meat of wild game animals (roe deer, boar, rabbit, pheasant, and pigeon) in North-Western Spain were tested for susceptibility to 14 antimicrobials by the disc diffusion method. All strains showed a multi-resistant phenotype (resistance to between three and 10 antimicrobials). The strains exhibited high percentages of resistance to erythromycin (89.1%), tetracycline (67.3%), ciprofloxacin (92.7%), nitrofurantoin (67.3%), and quinupristin-dalfopristin (81.8%). The lowest values (9.1%) were observed for high-level resistance to gentamicin, kanamycin, and streptomycin. The average number of resistances per strain was 5.8 for E. faecium isolates, 7.9 for E. faecalis, and 5.7 for E. durans. Genes encoding antimicrobial resistance and virulence were studied by polymerase chain reaction. A total of 15 (57.7%) of the 26 vancomycin-resistant isolates harboured the vanA gene. Other resistance genes detected included vanB, erm(B) and/or erm(C), tet(L) and/or tet(M), acc(6')-aph(2″), and aph(3')-IIIa in strains resistant to vancomycin, erythromycin, tetracycline, gentamicin, and kanamycin, respectively. Specific genes of the Tn5397 transposon were detected in 54.8% of the tet(M)-positive enterococci. Nine virulence factors (gelE, agg, ace, cpd, frs, esp, hyl, efaAfs and efaAfm) were studied. All virulence genes, with the exception of the frs gene, were found to be present in the enterococcal isolates. At least one virulence gene was detected in 20.0% of E. faecium, 71.4% of E. faecalis and 33.3% of E. durans isolates, with ace and cpd being the most frequently detected genes (6 isolates each). This suggests that wild game meat might play a role in the spreading through the food chain of enterococci with antimicrobial resistance and virulence determinants to humans. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Antimicrobial susceptibility of uropathogens from uncomplicated urinary tract infection in a pediatric hospital].

Science.gov (United States)

López-Martínez, Briceida; Calderón-Jaimes, Ernesto; Olivar-López, Víctor; Parra-Ortega, Israel; Alcázar-López, Virginia; Castellanos-Cruz, María Del Carmen; de la Garza-López, Alicia

Urinary tract infection in children is well recognized as a cause of acute morbidity and chronic medical conditions. As a result, appropriate use of antimicrobial agents, however, increases antibiotic resistance and complicates its treatment due to increased patient morbidity, costs, rates of hospitalization, and use of broader-spectrum antibiotics. The goal of this study was to determine antibiotic susceptibility to commonly used agents for urinary tract infection against recent urinary isolates. A total of 457 consecutive children attending the emergency room at the Hospital Infantil de México Federico Gómez with symptoms of uncomplicated lower urinary tract infection were eligible for inclusion. Patients who had had symptoms for≥7 days and those who had had previous episodes of urinary tract infection, received antibiotics or other complicated factors were excluded. Midstream and catheter urine specimens were collected. All isolates were identified and the in vitro activities of antimicrobials were determined. The most frequently isolated urinary pathogens were as follows: Escherichia coli (E. coli) (312, 68.3%), Enterococcus spp. (42, 11%), Klebsiella pneumoniae (K. pneumoniae) (40, 8.7%), Pseudomonas aeruginosa (P. aeruginosa) (34, 7.5%), Proteus mirabilis (P. mirabilis) (21, 4.5%), Enterobacter cloacae (8, 1.7%). The resistance to trimetoprim/sulfametoxazol (%) was 73.7, 62.2, 100, 52, and 50, respectively, for E. coli, K. pneumoniae, P. aeruginosa, P. mirabilis and Enterobacter spp., 92.5 for Enterococcus faecalis (E. faecalis) and 49.9 for Enterococcus faecium (E. faecium). Ampicillin was 86.3, 45, 100, 47.9, and 66.6% for the same strains, ciprofloxacin 33.8, 9, 18.8, 0, 0%, nitrofurantoin 4.4, 13, 97.7, 70, 0%; to E. faecalis 0% and 16.7% to E. faecium. Frequently prescribed empirical agents for uncomplicated urinary tract infection demonstrate lowered in vitro susceptibilities when tested against recent clinical isolates. Copyright © 2014 Hospital

Occurrence of the structural enterocin A, P, B, L50B genes in enterococci of different origin.

Science.gov (United States)

Strompfová, Viola; Lauková, Andrea; Simonová, Monika; Marcináková, Miroslava

2008-12-10

Enterococci are well-known producers of antimicrobial peptides--bacteriocins (enterocins) and the number of characterized enterocins has been significantly increased. Recently, enterocins are of great interest for their potential as biopreservatives in food or feed while research on enterocins as alternative antimicrobials in humans and animals is only at the beginning. The present study provides a survey about the occurrence of enterocin structural genes A, P, B, L50B in a target of 427 strains of Enterococcus faecium (368) and Enterococcus faecalis (59) species from different sources (animal isolates, food and feed) performed by PCR method. Based on our results, 234 strains possessed one or more enterocin structural gene(s). The genes of enterocin P and enterocin A were the most frequently detected structural genes among the PCR positive strains (170 and 155 strains, respectively). Different frequency of the enterocin genes occurrence was detected in strains according to their origin; the strains from horses and silage showed the highest frequency of enterocin genes presence. All possible combinations of the tested genes occurred at least twice except the combination of the gene of enterocin B and L50B which possessed neither strain. The gene of enterocin A was exclusively detected among E. faecium strains, while the gene of enterocin P, B, L50B were detected in strains of both species E. faecium and E. faecalis. In conclusion, a high-frequency and variability of enterocin structural genes exists among enterococci of different origin what offers a big possibility to find effective bacteriocin-producing strains for their application in veterinary medicine.

Cepas de Campylobacter jejuni resistentes a quinolonas aisladas de humanos, gallinas y pollos

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Rodolfo Notario

2011-08-01

Full Text Available Se compararon 8 aislamientos de Campylobacter jejuni provenientes de humanos con enfermedad diarreica aguda, con 23 aislamientos de cloaca de gallinas y pollos obtenidos de zonas próximas a la ciudad de Rosario, todos resistentes a la ciprofloxacina. Las muestras se sembraron en agar selectivo y se incubaron en microaerofilia a 42 °C. Las colonias se identificaron con el método tradicional. Los aislamientos se conservaron a -70 °C en caldo cerebro corazón con 17% v/v de glicerina. La clonalidad se determinó por RAPD-PCR, utilizando el primer 1254 (Stern NJ. Se interpretaron los aislamientos como clones distintos cuando diferían en una banda de amplificación. Se obtuvieron 5 clones diferentes. Los patrones I, II y V fueron aislados en criaderos industriales de pollos y en humanos (el II también en un establecimiento de gallinas ponedoras de huevos. En un gallinero familiar se obtuvo el patrón I. El patrón III sólo se obtuvo de humanos. El patrón IV se halló en uno de los criaderos pero no en humanos. Se pudo determinar que 93.5% de las cepas se aislaron tanto de animales como de humanos, por lo que se considera posible que la colonización de criaderos con cepas resistentes a los antimicrobianos pudiera ser el origen de la infección de humanos.

Factores de riesgo para bacteriemia por Pseudomonas aeruginosa resistente a carbapenémicos adquirida en un hospital colombiano

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Sandra Liliana Valderrama

2016-04-01

Conclusión. Para el control de la aparición de P. aeruginosa resistente a carbapenémicos, se deben fortalecer los programas de control de antimicrobianos, promover el uso prudente de carbapenémicos y quinolonas, y vigilar el uso adecuado de la nutrición parenteral.

Serological diagnosis of experimental Enterococcus faecalis endocarditis

DEFF Research Database (Denmark)

Kjerulf, A; Espersen, F; Gutschik, E

1998-01-01

A modified rat model of endocarditis with catheterization for 2 days was established in female Lewis rats using different inocula of Enterococcus faecalis (strain no. EF 19) in order to measure IgG antibodies in serum during the course of infection. Increasing the inocula intravenously resulted...

Manejo da Planta Daninha Brachiaria plantaginea Resistente aos herbicidas Inibidores da ACCase Management of the Weed Brachiaria plantaginea Resistant to ACCase Inhibitor Herbicides

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P.J. Christoffoleti

2001-04-01

Full Text Available O objetivo deste trabalho foi estudar o manejo de uma população da planta daninha capim-marmelada (Brachiaria plantaginea resistente aos herbicidas inibidores da ACCase (ariloxifenoxipropionatos e ciclohexanodionas, utilizados na cultura da soja no sistema de plantio direto. Para isso, foram realizados dois experimentos: um utilizando herbicidas de manejo, com mecanismos de ação alternativos, comparando a eficácia destes com os inibidores da ACCase; e outro apenas com herbicidas inibidores da ACCase e aditivos misturados à calda. As sementes resistentes foram produzidas a partir de plantas comprovadamente resistentes; para comparação de resultados, foi utilizada uma população de capim-marmelada que nunca tinha sido pulverizada com inibidores da ACCase, portanto uma população suscetível. O experimento com os herbicidas de manejo foi realizado em condições de campo, porém as plantas ficaram em caixas com capacidade de 50 L, evitando-se a disseminação destas para áreas adjacentes. Concluiu-se que as plantas resistentes não apresentam resistência múltipla com herbicidas de manejo com mecanismos de ação alternativos, podendo os herbicidas glyphosate, paraquat, sulfosate, paraquat + diuron, MSMA e glufosinate ser utilizados no período entressafra das áreas com sistema de plantio direto, para manejo de populações resistentes de capim-marmelada aos herbicidas inibidores da ACCase. O experimento com aditivos foi realizado em casa de vegetação, com plantas em vasos individuais, utilizando sementes das populações suscetíveis e resistentes. Os herbicidas utilizados foram inibidores da ACCase, em cuja calda foram adicionados aditivos nitrogenados, do tipo uréia e sulfato de amônio, além de um tratamento sem aditivos. Concluiu-se que os aditivos não alteraram a eficácia dos herbicidas inibidores da ACCase nas plantas provenientes tanto da população suscetível quanto da resistente.The objective of this research was to

Analysis of the lactic acid bacteria microflora in traditional Caucasus cow's milk cheeses

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Terzić-Vidojević Amarela

2009-01-01

Full Text Available A total of 157 lactic acid bacteria (LAB were isolated from three hand-made cheeses taken from different households in the region of the Caucasus Mountains. The cheeses were manufactured from cow's milk without the addition of a starter culture. The isolates of LAB were characterized by subjecting them to phenotypic and genotypic tests. The results of identification of LAB indicate that the examined cheeses contained 10 species, viz., Lactobacillus plantarum, Lactobacillus paraplantarum, Lactobacillus arizonensis, Lactobacillus farciminis, Lactobacillus brevis, Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc pseudomesenteroides, Enterococcus faecium, and Enterococcus faecalis. The strains within the species L. plantarum, L. arizonensis, L. paraplantarum, L. farciminis, and L. pseudomesenteroides showed good proteolytic activity.

A Meta-analysis of the Rates of Listeria monocytogenes and Enterococcus in Febrile Infants.

Science.gov (United States)

Leazer, Rianna; Perkins, Amy M; Shomaker, Kyrie; Fine, Bryan

2016-04-01

A change in the epidemiology of pathogens causing serious bacterial infection (SBI) has been noted since original recommendations were made for the empirical antibiotic choices for young infants with fever. To assess the prevalence of SBI caused by Listeria monocytogenes and Enterococcus species. A literature search was conducted on keywords related to SBI, L. monocytogenes, and Enterococcus spp. infections. Eligible studies were those conducted in the United States and published between January 1998 and June 2014 focusing on SBI in infants≤90 days of age. The rates of urinary tract infection, bacteremia, and meningitis for each pathogen were recorded for each study. Meta-analysis was performed to calculate the prevalence for each pathogen in a random effects model with 0.5 continuity correction added to studies with zero events. Sixteen studies were included. A total of 20,703 blood cultures were included, with weighted prevalences for L. monocytogenes and Enterococcus spp. bacteremia of 0.03% and 0.09%, respectively. A total of 13,775 cerebrospinal fluid cultures were included with event rates (unweighted prevalences) for L. monocytogenes and Enterococcus spp. meningitis of 0.02% and 0.03%, respectively. A total of 18,283 urine cultures were included, with no cases of L. monocytogenes and a weighted prevalence for Enterococcus spp. urinary tract infection of 0.28%. There may have been reporting bias or incomplete retrieval or inadvertent exclusion of relevant studies. SBI caused by L. monocytogenes and Enterococcus spp. in febrile infants is rare, and therefore clinicians may consider a change in empirical antibiotic choices. Copyright © 2016 by the American Academy of Pediatrics.

Biofilm-forming capacity in biogenic amine-producing bacteria isolated from dairy products.

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Maria eDiaz

2016-05-01

Full Text Available Biofilms on the surface of food industry equipment are reservoirs of potentially food-contaminating bacteria - both spoilage and pathogenic. However, the capacity of biogenic amine (BA-producers to form biofilms has remained largely unexamined. BAs are low molecular weight, biologically active compounds that in food can reach concentrations high enough to be a toxicological hazard. Fermented foods, especially some types of cheese, accumulate the highest BA concentrations of all. The present work examines the biofilm-forming capacity of 56 BA-producing strains belonging to three genera and 10 species (12 Enterococcus faecalis, 6 Enterococcus faecium, 6 Enterococcus durans, 1 Enterococcus hirae, 12 Lactococcus lactis, 7 Lactobacillus vaginalis, 2 Lactobacillus curvatus, 2 Lactobacillus brevis, 1 Lactobacillus reuteri and 7 Lactobacillus parabuchneri, all isolated from dairy products. Strains of all the tested species - except for L. vaginalis - were able to produce biofilms on polystyrene and adhered to stainless steel. However, the biomass produced in biofilms was strain-dependent. These results suggest that biofilms may provide a route via which fermented foods can become contaminated by BA-producing microorganisms.

Chromosome and cell wall segregation in Streptococcus faecium ATCC 9790

International Nuclear Information System (INIS)

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

Prevalencia y características de los pacientes con hipertensión arterial resistente y enfermedad renal crónica

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Úrsula Verdalles

2016-09-01

Conclusión: La prevalencia de HTA resistente aumenta con la edad, el grado de ERC y la albuminuria. Estrategias como el tratamiento con antagonistas de receptores de aldosterona se asocian con un mejor control tensional en este grupo de pacientes y disminuyen su prevalencia.

Efficiency of peracetic acid in inactivating bacteria, viruses, and spores in water determined with ATP bioluminescence, quantitative PCR, and culture-based methods.

Science.gov (United States)

Park, Eunyoung; Lee, Cheonghoon; Bisesi, Michael; Lee, Jiyoung

2014-03-01

The disinfection efficiency of peracetic acid (PAA) was investigated on three microbial types using three different methods (filtration-based ATP (adenosine-triphosphate) bioluminescence, quantitative polymerase chain reaction (qPCR), culture-based method). Fecal indicator bacteria (Enterococcus faecium), virus indicator (male-specific (F(+)) coliphages (coliphages)), and protozoa disinfection surrogate (Bacillus subtilis spores (spores)) were tested. The mode of action for spore disinfection was visualized using scanning electron microscopy. The results indicated that PAA concentrations of 5 ppm (contact time: 5 min), 50 ppm (10 min), and 3,000 ppm (5 min) were needed to achieve 3-log reduction of E. faecium, coliphages, and spores, respectively. Scanning electron microscopy observation showed that PAA targets the external layers of spores. The lower reduction rates of tested microbes measured with qPCR suggest that qPCR may overestimate the surviving microbes. Collectively, PAA showed broad disinfection efficiency (susceptibility: E. faecium > coliphages > spores). For E. faecium and spores, ATP bioluminescence was substantially faster (∼5 min) than culture-based method (>24 h) and qPCR (2-3 h). This study suggests PAA as an effective alternative to inactivate broad types of microbial contaminants in water. Together with the use of rapid detection methods, this approach can be useful for urgent situations when timely response is needed for ensuring water quality.

Prevalence and antibiotics susceptibility profile of Enterococcus spp ...

African Journals Online (AJOL)

This study investigated the prevalence and antibiotics susceptibility of Enterococcus spp. isolated from patients and some selected hospital environment in Abuja, Nigeria. The samples included clinical and environmental. The clinical samples included stool, urine and wound swabs while the environmental samples ...

Multidrug-Resistant Enterococcal Infections: New Compounds, Novel Antimicrobial Therapies?

Science.gov (United States)

van Harten, Roel M; Willems, Rob J L; Martin, Nathaniel I; Hendrickx, Antoni P A

2017-06-01

Over the past two decades infections due to antibiotic-resistant bacteria have escalated world-wide, affecting patient morbidity, mortality, and health care costs. Among these bacteria, Enterococcus faecium and Enterococcus faecalis represent opportunistic nosocomial pathogens that cause difficult-to-treat infections because of intrinsic and acquired resistance to a plethora of antibiotics. In recent years, a number of novel antimicrobial compound classes have been discovered and developed that target Gram-positive bacteria, including E. faecium and E. faecalis. These new antibacterial agents include teixobactin (targeting lipid II and lipid III), lipopeptides derived from nisin (targeting lipid II), dimeric vancomycin analogues (targeting lipid II), sortase transpeptidase inhibitors (targeting the sortase enzyme), alanine racemase inhibitors, lipoteichoic acid synthesis inhibitors (targeting LtaS), various oxazolidinones (targeting the bacterial ribosome), and tarocins (interfering with teichoic acid biosynthesis). The targets of these novel compounds and mode of action make them very promising for further antimicrobial drug development and future treatment of Gram-positive bacterial infections. Here we review current knowledge of the most favorable anti-enterococcal compounds along with their implicated modes of action and efficacy in animal models to project their possible future use in the clinical setting. Copyright © 2017 Elsevier Ltd. All rights reserved.

New antimicrobial contact catalyst killing antibiotic resistant clinical and waterborne pathogens

Energy Technology Data Exchange (ETDEWEB)

Guridi, A. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Diederich, A.-K. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Aguila-Arcos, S.; Garcia-Moreno, M. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Blasi, R.; Broszat, M. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Schmieder, W.; Clauss-Lendzian, E. [Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany); Sakinc-Gueler, T. [University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Andrade, R. [Advanced Research Facilities (SGIker), University of the Basque Country, UPV/EHU, 48940 Leioa (Spain); Alkorta, I. [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); Meyer, C.; Landau, U. [Largentec GmbH, Am Waldhaus 32, 14129 Berlin (Germany); Grohmann, E., E-mail: elisabeth.grohmann@googlemail.com [Biophysics Unit (CSIC, UPV/EHU), Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa (Spain); University Medical Center Freiburg, Division of Infectious Diseases, Hugstetter Strasse 55, 79106 Freiburg (Germany); Biology II, Microbiology, Albert-Ludwigs-University Freiburg, Schänzlestrasse 1, 79104 Freiburg (Germany)

2015-05-01

Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties. The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells. - Highlights: • The novel antimicrobial inhibits growth of clinical staphylococci and enterococci. • The novel antimicrobial inhibits growth of Legionella in drinking water. • A putative mode of action of the antimicrobial coating is presented.

New antimicrobial contact catalyst killing antibiotic resistant clinical and waterborne pathogens

International Nuclear Information System (INIS)

Guridi, A.; Diederich, A.-K.; Aguila-Arcos, S.; Garcia-Moreno, M.; Blasi, R.; Broszat, M.; Schmieder, W.; Clauss-Lendzian, E.; Sakinc-Gueler, T.; Andrade, R.; Alkorta, I.; Meyer, C.; Landau, U.; Grohmann, E.

2015-01-01

Microbial growth on medical and technical devices is a big health issue, particularly when microorganisms aggregate to form biofilms. Moreover, the occurrence of antibiotic-resistant bacteria in the clinical environment is dramatically growing, making treatment of bacterial infections very challenging. In search of an alternative, we studied a novel antimicrobial surface coating based on micro galvanic elements formed by silver and ruthenium with surface catalytic properties. The antimicrobial coating efficiently inhibited the growth of the nosocomial pathogens Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium as demonstrated by the growth inhibition on agar surface and in biofilms of antibiotic resistant clinical E. faecalis, E. faecium, and S. aureus isolates. It also strongly reduced the growth of Legionella in a drinking water pipeline and of Escherichia coli in urine. We postulate a mode of action of the antimicrobial material, which is independent of the release of silver ions. Thus, the novel antimicrobial coating could represent an alternative to combat microbial growth avoiding the toxic side effects of high levels of silver ions on eukaryotic cells. - Highlights: • The novel antimicrobial inhibits growth of clinical staphylococci and enterococci. • The novel antimicrobial inhibits growth of Legionella in drinking water. • A putative mode of action of the antimicrobial coating is presented

Características fenotípicas da hipertensão arterial resistente na população brasileira Phenotypic characteristics of resistant hypertension in the Brazilian population

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Ana Paula Cabral de Faria

2013-01-01

Full Text Available Hipertensão resistente (HAR é definida como a pressão arterial que permanece acima da meta pressórica, apesar do uso de três classes de anti-hipertensivos em doses otimizadas, sendo um deles um diurético. Além disso, são considerados também hipertensos resistentes os pacientes que usam quatro ou mais classes e possuem suas pressões controladas. Embora essa definição seja útil na categorização de um maior grupo de resistentes, visto esses dois subgrupos compartilharem alto risco cardiovascular, algumas importantes particularidades clínicas e fisiopatológicas necessitam ser mais bem avaliadas antes de resistentes controlados e não controlados pertencerem ao mesmo grupo. Foram comparadas algumas características cardiovasculares nesses dois subgrupos de hipertensos resistentes. Embora algumas semelhanças, o subgrupo HRNC apresenta fenótipos cardiovasculares com pior prognóstico como maior rigidez vascular e hipertrofia ventricular esquerda, além de função endotelial mais prejudicada e menor queda de pressão arterial no período noturno, entre outras. Frente às diferenças, o subgrupo HRNC está associado à maior risco cardiovascular, podendo ser considerado mais resistente ao tratamento anti-hipertensivo. Além da importância de melhor prevenção e tratamento da HAR com medidas de identificar precocemente os fatores de risco e otimizar a terapia farmacológica, algumas implicações clínicas devem ser consideradas na abordagem de pacientes controlados e não controlados como semelhantes ao grupo de resistentes.Resistant hypertension (RH is defined as blood pressure that remains above target in spite of the concurrent use of three or more classes of antihypertensive drugs at optimized doses (UCRH, with one of them being a diuretic. Moreover, patients whose blood pressure is controlled while using four or more antihypertensive medications are also considered controlled resistant hypertensive (CRH subjects. Although this

Epidemia de tuberculosis multidrogo resistente y extensivamente resistente a drogas (TB MDR/XDR en el Perú: situación y propuestas para su control

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Hernán Del Castillo

2009-07-01

Full Text Available En este artículo se describe el estado actual de las epidemias de tuberculosis multidrogo resitente (TB MDR y tuberculosis extensivamente resistente a drogas (TB XDR en el Perú. Se realiza un análisis de nuestra situación con respecto al resto de Latinoamérica, y de la distribución temporo espacial de los casos de TB XDR en Lima. También presentamos nuestra reflexión de lo que está pasando y debe cambiar; lo que se resume en darle la importancia debida a un problema que nos está rebasando y anteponer a nuestros propios intereses, los intereses de la humanidad; por consiguiente no podemos callar, y debemos declarar a la tuberculosis como emergencia sanitaria nacional. Eso constituye una respuesta, esperamos, aún viable para el Perú.

A 1.5 hour procedure for identification of Enterococcus Species directly from blood cultures.

Science.gov (United States)

Morgan, Margie A; Marlowe, Elizabeth; Novak-Weekly, Susan; Miller, J M; Painter, T M; Salimnia, Hossein; Crystal, Benjamin

2011-02-10

Enterococci are a common cause of bacteremia with E. faecalis being the predominant species followed by E. faecium. Because resistance to ampicillin and vancomycin in E. faecalis is still uncommon compared to resistance in E. faecium, the development of rapid tests allowing differentiation between enterococcal species is important for appropriate therapy and resistance surveillance. The E. faecalis OE PNA FISH assay (AdvanDx, Woburn, MA) uses species-specific peptide nucleic acid (PNA) probes in a fluorescence in situ hybridization format and offers a time to results of 1.5 hours and the potential of providing important information for species-specific treatment. Multicenter studies were performed to assess the performance of the 1.5 hour E. faecalis/OE PNA FISH procedure compared to the original 2.5 hour assay procedure and to standard bacteriology methods for the identification of enterococci directly from a positive blood culture bottle.

Probiotic treatment decreases the number of CD14 expressing cells in porcine milk which correlates with several intestinal immune parameters in the piglets.

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Lydia eScharek-Tedin

2015-03-01

Full Text Available Modulating the mucosal immune system of neonates by probiotic treatment of their mothers is a promising approach which can only be investigated through the use of animal models. Here, we used sows and their piglets to investigate the impact of a bacterial treatment on the sow´s milk and on the neonate piglet intestinal immune system.In previous experiments, feed supplementation of sows with the probiotic Enterococcus faecium NCIMB 10415 during pregnancy and lactation had been shown to affect intestinal microbiota and cytokine expression of the offspring during the suckling and weaning periods. We therefore investigated the composition of the milk from treated sows in comparison to samples from a control group. In treated sows, the amount of lactose increased, and the somatic cell numbers were reduced. In all milk samples, the percentage of cells expressing membranous CD14 (mCD14 was greater than the fractions of immune cells, indicating expression of mCD14 on mammary epithelial cells. However, in the milk of E. faecium-treated sows, mCD14+ cells were reduced. Furthermore, the number of CD14+ milk cells was positively correlated with the percentages of B cells and activated T cells in the ileal MLN of the piglets. This study provides evidence for the expression of mCD14 by the porcine mammary epithelium, and suggests an immunological effect of mCD14+ milk cells on the piglets’ intestinal immune system. Our study further suggests that mCD14+ mammary epithelial cell populations can be modulated by probiotic feed supplementation of the sow. Keywords: pig, Enterococcus faecium, milk, mCD14, intestinal, B cells, T cells.

Insusceptibility to disinfectants in bacteria from animals, food and humans – is there a link to antimicrobial resistance?

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Karin eSchwaiger

2014-03-01

Full Text Available Enterococcus faecalis (n = 834 and Enterococcus faecium (n = 135 from blood and feces of hospitalized humans, from feces of outpatients and livestock and from food were screened for their susceptibility to a quaternary ammonium compound (didecyldimethyl-ammoniumchloride, DDAC and to 28 antibiotics by micro-/macrodilution. The maximum DDAC-MIC in our field study was 3.5 mg/l, but after adaptation in the laboratory, MIC values of 21.9 mg/l were observed. Strains for which DDAC had MICs > 1.4 mg/l (non-wildtype, in total: 46 of 969 isolates / 4. 7 % were most often found in milk and dairy products (14.6 %, while their prevalence in livestock was generally low (0-4 %. Of human isolates, 2.9 to 6.8 % had a non-wildtype phenotype. An association between reduced susceptibility to DDAC, high-level-aminoglycoside resistance and aminopenicillin resistance was seen in E. faecium (p In addition, bacteria (n = 42 of different genera were isolated from formic acid based boot bath disinfectant (20 ml of 55 % formic acid /l. The MICs of this disinfectant exceeded the wildtype MICs up to 20fold (staphylococci, but were still one to three orders of magnitude below the used concentration of the disinfectant (i. e. 1.1 % formic acid. In conclusion, the bacterial susceptibility to disinfectants still seems to be high. Thus, the proper use of disinfectants in livestock surroundings along with a good hygiene praxis should still be highly encouraged. Hints to a link between antibiotic resistance and reduced susceptibility for disinfectants – as seen for E. faecium - should be substantiated in further studies and might be an additional reason to confine the use of antibiotics.

Incidence of virulence determinants in clinical Enterococcus faecalis and Enterococcus faecium isolates collected in Bulgaria

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Tanya Strateva

2016-03-01

Conclusion: Most E. faecalis attaches to abiotic surfaces in hospital environment, which correlates with higher prevalence of gene encoding for virulence factors involved in biofilm formation, such as enterococcal surface protein, aggregation substance, and gelatinase. The intestinal tract is an important reservoir for opportunistic enterococcal pathogens and allows them to access infectious sites through different virulence factors, demonstrated in outpatient isolates in this study.

Sensibilidad al benzonidazol de cepas de Trypanosoma cruzi sugiere la circulación de cepas naturalmente resistentes en Colombia

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Ana María Mejía-Jaramillo

2012-06-01

Full Text Available Introducción. La enfermedad de Chagas, causada por Trypanosoma cruzi, es uno de los problemas más graves de salud pública en el continente americano. El benzonidazol es uno de los dos medicamentos utilizados para tratar la enfermedad de Chagas. Sin embargo, la variación de la sensibilidad del parásito a este medicamento es una de las principales causas del fracaso del tratamiento. Objetivo. Evaluar la sensibilidad in vitro al benzonidazol de cepas colombianas de T. cruzi de diferentes orígenes y procedencia geográfica. Materiales y métodos. Treinta y tres cepas colombianas de T. cruzi aisladas de humanos, vectores y mamíferos, se analizaron in vitro mediante el micrométodo enzimático de MTT para determinar la concentración inhibitoria 50 (CI50 al benzonidazol. Se estudió la correlación entre la sensibilidad in vitro al medicamento y diferentes parámetros biológicos y eco-epidemiológicos. Resultados. El análisis de sensibilidad al medicamento indicó que el 36 % de las cepas eran sensibles, el 48 %, parcialmente resistentes y, el 16 %, resistentes al benzonidazol. Los análisis de correlación entre las CI50 con algunos parámetros biológicos y eco-epidemiológicos, mostraron diferencias en cuanto a la sensibilidad según el origen biológico y el área geográfica de procedencia de la cepa. Conclusiones. Existe una gran variabilidad en cuanto a la sensibilidad al benzonidazol de las cepas circulantes de T. cruzi en Colombia, lo cual sugiere la presencia de cepas naturalmente resistentes en el país.   doi: http://dx.doi.org/10.7705/biomedica.v32i2.458

Is there a need for bacterial endocarditis prophylaxis in patients undergoing gastrointestinal endoscopy?

Science.gov (United States)

Patanè, Salvatore

2014-04-01

Heart valve repair or replacement is a serious problem. Patients can benefit from an open dialogue between both cardiologists and gastroenterologists for the optimal effective patients care. The focused update on infective endocarditis of the American College of Cardiology/American Heart Association 2008 (ACC/AHA guidelines) and guidelines on the prevention, diagnosis, and treatment of infective endocarditis (new version 2009) of the European Society of Cardiology (ESC guidelines) describe prophylaxis against infective endocarditis (IE) as not recommended for gastroscopy and colonoscopy in the absence of active infection but increasing evidence suggests that the role of IE antibiotic prophylaxis remains a dark side of the cardio-oncology prevention. New evidences concerning infective endocarditis due to Streptococcus bovis, Streptococcus agalactiae, Enterococcus faecalis, Enterococcus faecium, Enterococcus durans, and new findings indicate that there is a need for bacterial endocarditis prophylaxis in patients undergoing gastrointestinal endoscopy especially in elderly patients and in cancer and immunocompromised patients, to avoid serious consequences.

Identification of Predominant Lactic Acid Bacteria and Yeasts of Turkish Sourdoughs and Selection of Starter Cultures for Liquid Sourdough Production Using Different Flours and Dough Yields

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Yağmur Gülten

2016-06-01

Full Text Available Eight samples of mature sourdough were collected from five provinces of Turkey. Lactic acid bacteria and yeasts were isolated and identified and used in different combinations to produce liquid sourdoughs. Microbiological and physicochemical characteristics of the experimental sourdoughs made with different flour types and dough yields were studied. The main lactic acid bacteria species identified were Lactobacillus (L. sanfranciscensis, Pediococcus pentosaceus, L. plantarum, L. namurencis, L. rossiae, Leuconostoc mesenteroides and L. zymae. L. spicheri, L. paralimentarius, L. mindensis, L. farciminis, L. acetotolerans, L. casei, Enterococcus faecium and Enterococcus durans were also found in sourdoughs at subdominant levels. Among yeasts, mainly Saccharomyces cerevisiae, but also Pichia guiliermondii and Torulaspora delbrueckii were the predominant species of yeasts identified in sourdoughs.

Purification and characterization of enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4.

Science.gov (United States)

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

Purification and characterization of enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4.

OpenAIRE

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.

Evaluation of the quality of coastal bathing waters in Spain through fecal bacteria Escherichia coli and Enterococcus.

Science.gov (United States)

Aragonés, L; López, I; Palazón, A; López-Úbeda, R; García, C

2016-10-01

Sun. and beach tourism is very important to the economy of Spain, so the control of the quality of the environment on the beaches is essential. Therefore, the analysis and control of the quality of bathing water is necessary, which is defined by the European Directive 2006/7/EC as excellent, good or sufficient depending on the presence of microbiological contamination or other organisms or waste presenting a risk to bathers' health. For that, 1392 beaches of the Iberian Peninsula and its islands were analysed, taking into account: fecal bacteria (Escherichia coli and Enterococcus), physical characteristics of sediment, level of urbanization, climatic and anthropogenic factors, and maritime climate. Thus, it was observed that urban sand beaches located in seas with fewer hours of sunshine and important tide have higher concentrations of E. coli and Enterococcus. There is also an indirect relationship between these microorganisms with salinity (R(2) 0.746 for E. coli and 0.606 for Enterococcus), temperature (R(2) 0.743 for E. coli and 0.604 for Enterococcus) and hours of sunshine (R(2) 0.781 for E. coli and 0.706 for Enterococcus), while this relationship is direct with rainfall (R(2) 0.640 for E. coli and 0.607 for Enterococcus) or wave height (R(2) 0.769 for E. coli and 0.601 for Enterococcus). From all this, it follows that the Directive 2006/7/EC should define more specific criteria as to the place and time of sampling, and take into account the different environment variables that influence the survival of bacteria, so that the results may reflect reality, and avoid staff responsible for sampling freely choose the place and time of sampling. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison between syringe irrigation and RinsEndo in reduction of Enterococcus faecalis in experimentally infected root canal

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Sharareh Mousavi Zahed

2015-05-01

Full Text Available Background and Aims: To ensure root canal treatment success, endodontic microbiota should be efficiently reduced. Several irrigation devices have been recently introduced with the main objective of improving root canal disinfection.The purpose of this study was to evaluate the rinsing effect of RinsEndo system in reduction of enterococcus faecalis in comparison with conventional hand syringe in infected root canals.   Materials and Methods: 60 extracted single canal anterior teeth were infected with enterococcus faecalis and divided into 3 groups: RinsEndo system, conventional hand syringe and control group. The enterococcus faecalis colonies were counted in each group before and after rinsing. Data were analyzed using Variance and Kruskal Wallis test.   Results: The mean of enterococcus faecalis growth after rinsing was 3.50×103 in group with conventional syring rinsing, 2.04×103 in group with RinsEndo washing and 6.11×103 in control group. Reduction of enterococcus faecalis after rinsing was statistically significant in each group (P<0.001. The amount of reduction in number of colonies with RinsEndo and conventional syringe rinsing was higher in comparison with control group and this difference was significant (P<0.001. RinsEndo rinsing effect was statistically significantly higher in comparison to conventional syringe as well (P<0.001.   Conclusion: Rinsing with RinsEndo system was significantly more efficient in reduction of enterococcus faecalis from root canal in comparison with hand syringe washing.

Staphylococcus aureus resistente a meticilina adquirido en la comunidad aislados en tres hospitales de Lima-Perú

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Jesús Tamariz

2010-01-01

Full Text Available Staphylococcus aureus es un importante patógeno involucrado en una serie de infecciones e intoxicaciones, presenta múltiples factores de virulencia y su impacto se incrementa por su notable resistencia a los antimicrobianos. Objetivo: Determinar la frecuencia de Staphylococcus aureus meticilino resistente adquiridos en la comunidad, en hospitales de Lima- Perú. Material y métodos: Se realizó un estudio descriptivo multicéntrico. La resistencia a meticilina se determinó por el método Oxacillin Agar Screen. El origen de la cepa fue determinado mediante los criterios de los CDC; la Leucocidina de Panton Valentine fue identificada por métodos moleculares. Resultados: Se aislaron 276 cepas de Staphylococcus aureus, 160 fueron resistentes a meticilina (58%, 9 de ellas fueron identificadas como adquiridas en la comunidad (5,6%. La PVL fue identificada en 25 cepas (9,1%, 14 fueron MSSA y 11 MRSA, de éstas últimas solo 4 fueron MRSAcom, 7 fueron MRSAhosp (p<0,001. Conclusiones: El estudio revela niveles elevados de resistencia a meticilina, pero niveles bajos de MRSAcom. En nuestro medio la presencia de PVL no constituiría un marcador para la identificación de los MRSAcom. (Rev Med Hered 2010;21:4-10.

Draft genome sequences of two commensal Enterococcus cecorum strains isolated from chickens in Belgium

DEFF Research Database (Denmark)

Dolka, Beata; Boyen, Filip; Butaye, Patrick

2015-01-01

Here, we report the draft genome sequences of two commensal Enterococcus cecorum strains (1710s23 and 1711s24), cultivated from the ceca of healthy laying hens originating from different farms in Belgium.......Here, we report the draft genome sequences of two commensal Enterococcus cecorum strains (1710s23 and 1711s24), cultivated from the ceca of healthy laying hens originating from different farms in Belgium....

Tuberculose multi-resistente. A propósito de um caso clínico de reinfeção exógena adquirida no meio prisional

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José Leon Bernardo

1998-05-01

Full Text Available RESUMO: Os autores descrevem um caso clinic de tuberculose multi-resistente num doente recluse, toxicodependente e com SIDA que se encontrava sob terapêutiea antibacilar em virtude de anterior episodin de tuberculose “sendivel”.Comentam alguns aspectos relacionadus com o diagnostic, tratamento e evoução exógena por estirpe multi-resistente.Em conclusão, us autores salientam o interesse do DNA “fingerprinting” no diagnostic e epidemiologia da tuberculose multi-resistente e a necessidade de implementação de um efectivo programa de luta contra a tuberculose multi-resistente na comunidade prisional.REV PORT PNEUMOL 1998; IV (3: 319-325 ARSTRACT: A case of multidrug-resistant tuberculosis in a drug-addicted and jailed patient with AIDS is reported. The patient was in anti-tuberculosis therapy, because a question of ongoing “sensitive” tuberculosis.The authors comment some aspects of the clinical management of the patient. Exogenous reinfection with a multidrug-resistant strain was convincelly demonstrated with DNA fingerprinting.The relevance of DNA fingerprinting in the diagnosis and epidemiology of multidrug-resistant tuberculosis is emphasized and the reformulation of the anti-tuberculosis programme in the prisional setting is warranted, in the face of ongoing transmissionREV PORT PNEUMOL 1998; IV (3: 319-325 Palavras-chave: Tuberculose multirresistente, RFLP, Key-words: Multidrug-resistant tuberculosis (MDR-TB, RELP

Phenolic compounds, methylxanthines and antioxidant activity in cocoa mass and chocolates produced from "witch broom disease" resistant and non resistant cocoa cultivars Compostos fenólicos, metilxantinas e atividade antioxidante em massa de cacau e chocolates produzidos a partir de cultivares resistentes e não resistentes a "vassoura de bruxa"

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Paula Bacelar Leite

2013-06-01

Full Text Available The "witch broom disease" caused by the fungus called Moniliophthora perniciosa is one of the most important cocoa diseases in Latin America, causing around 70% production reduction in the southern Bahia. In attempt to solve the problem, many cultivars resistant to the disease have been recommended to farmers. On the other hand, the chocolate flavour is composed by many compounds whose formation depends on the genetic background, environment where cocoa is grown and processing operations. Therefore, this work aimed at determining the monomeric phenolic compounds, methylxanthines and antioxidant activity of cocoa mass and dark chocolate from cocoa cultivars resistant to "witch broom disease" and non resistant to the disease. The total phenolic compounds in cocoa mass did not vary among cultivars with values ranging from 23.95mg g-1 to 25.03mg g-1. Chocolates made from non resistant cultivars showed higher total phenolic compounds (19.11mg g-1 than SR162 and PH16 with 16.08mg g-1 and 15.46mg g-1, respectively. Epicatechin had higher content than catechin and the levels of these two compounds were higher in SR162. There were significant differences among samples of cocoa mass analyzed for caffeine. Chocolate made from SR162 had the highest amount of monomeric compounds due to its high concentration of catechin and epicatechin. The chocolate sample with the highest antioxidant activity was the SR162, followed by non resistant blend and PH16, showing relationship between the antioxidant activity and monomeric phenolics content.A "vassoura bruxa" causada pelo fungo Moniliophthora perniciosa, é uma das doenças mais importantes do cacau na América Latina, provocando uma redução de cerca de 70% na produção das amêndoas na Bahia. Para tentar resolver o problema, muitos cultivares resistentes à enfermidade têm sido recomendados para os agricultores. Por outro lado, as características do chocolate são oriundas de várias substâncias, cuja forma

Personalidad resistente en maratonianos: un estudio sobre el control, compromiso y desafío de corredoras y corredores de maratón

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Jos\\u00E9 Carlos Jaenes S\\u00E1nchez

2009-01-01

Full Text Available La Personalidad Resistente se refiere a una constelación de características de personalidad relacionadas con las percepciones personales de control, compromiso y desafío, que ha sido ampliamente estudiada en relación con el estrés y su impacto en contextos de salud y laborales, entre otros, pero prácticamente ignorada en el ámbito deportivo. Sin embargo, las características que incluye este constructo son muy interesantes para la práctica y el rendimiento deportivos. El objetivo de este estudio ha sido conocer las características de Personalidad Resistente de maratonianos adultos españoles. Los resultados, pioneros hasta la fecha, nos han permitido establecer que los niveles de compromiso, control y desafío de estos deportistas son moderadamente altos y que ejercen un impacto fundamental tanto a nivel motivacional (metas propuestas y resultados esperados como de rendimiento (marcas obtenidas. Se puede diferenciar entre maratonianos con mejores y peores marcas en relación con el nivel de PR, lo cual nos permite predecir el éxito de los maratonianos en función de sus características de PR. Como consecuencia, un entrenamiento adecuado en estas aracterísticas podría resultar en mejores cotas de rendimiento. Además, estos deportistas muestran mayores niveles de Personalidad Resistente que jóvenes y adultos de la población general, lo que podría ser un beneficio derivado de la práctica deportiva muy relevante en la vida cotidiana.

Isolation, enumeration, molecular identification and probiotic potential evaluation of lactic acid bacteria isolated from sheep milk

OpenAIRE

Acurcio, L.B.; Souza, M.R.; Nunes, A.C.; Oliveira, D.L.S.; Sandes, S.H.C.; Alvim, L.B.

2014-01-01

Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%), E. durans (31.25%) and E. casseliflavus (12.5%). No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0) and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime,...

Influence of Streptococcus mutans on Enterococcus faecalis Biofilm Formation

NARCIS (Netherlands)

Deng, Dong Mei; Hoogenkamp, Michel A.; Exterkate, Rob A. M.; Jiang, Lei Meng; van der Sluis, Lucas W. M.; ten Cate, Jacob M.; Crielaard, Wim

Introduction: An important virulence factor of Enterococcus faecalis is its ability to form biofilms. Most studies on biofilm formation have been carried out by using E. faecalis monocultures. Given the polymicrobial nature of root canal infections, it is important to understand biofilm formation of

Whole-cell protein profiles are useful for distinguishing enterococcal species recovered from clinical specimens Los perfiles de proteínas totales son útiles para distinguir especies de enterococos recuperados de muestras clínicas

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R. Massa

2007-12-01

Full Text Available Whole-cell protein analysis was performed for differentiating 150 enterococcal isolates to the species level, which had previously been identified by extended phenotypic conventional tests. Whole-cell protein profile (WCPP showed a high degree of similarity within species and comparison between species revealed important differences in band profiles. All Enterococcus faecalis and Enterococcus faecium isolates were properly located into their corresponding species, regardless of their clinical source and susceptibility pattern. Moreover, WCPP allowed relocation of some isolates that had erroneously been identified by the usual conventional scheme (i.e. two atypical arginine-negative E. faecalis isolates. WCPP proved to be a simple method to ascertain the various enterococcal species, especially those other than E. faecalis, and may be a suitable tool for high-complexity or reference clinical laboratories.La comparación del perfil de proteínas totales permitió agrupar 150 aislamientos de enterococos dentro de la especie en la que habían sido ubicados por el esquema convencional de pruebas bioquímicas. Los patrones de proteínas totales, comparados visualmente, se mantuvieron con alto grado de similitud intraespecie y revelaron diferencias notorias en la comparación interespecie. Todos los aislamientos de Enterococcus faecalis y Enterococcus faecium, independientemente de los sitios de aislamiento, cuadro clínico del paciente, biotipo o antibiotipo, fueron fácilmente encuadrados en su especie. Asimismo, el estudio del perfil de proteínas totales de enterococos permitió reubicar taxonómicamente aislamientos que habían sido incorrectamente identificados por los métodos bioquímicos convencionales, como por ejemplo dos aislamientos atípicos de E. faecalis arginina negativos. Dado que la metodología empleada es económica y rápida, la comparación de perfiles de proteínas totales en SDS-PAGE podría ser considerada una herramienta

Antimicrobial activity, antibiotic susceptibility and virulence factors of Lactic Acid Bacteria of aquatic origin intended for use as probiotics in aquaculture

Science.gov (United States)

2013-01-01

Background The microorganisms intended for use as probiotics in aquaculture should exert antimicrobial activity and be regarded as safe not only for the aquatic hosts but also for their surrounding environments and humans. The objective of this work was to investigate the antimicrobial/bacteriocin activity against fish pathogens, the antibiotic susceptibility, and the prevalence of virulence factors and detrimental enzymatic activities in 99 Lactic Acid Bacteria (LAB) (59 enterococci and 40 non-enterococci) isolated from aquatic animals regarded as human food. Results These LAB displayed a broad antimicrobial/bacteriocin activity against the main Gram-positive and Gram-negative fish pathogens. However, particular safety concerns based on antibiotic resistance and virulence factors were identified in the genus Enterococcus (86%) (Enterococcus faecalis, 100%; E. faecium, 79%). Antibiotic resistance was also found in the genera Weissella (60%), Pediococcus (44%), Lactobacillus (33%), but not in leuconostocs and lactococci. Antibiotic resistance genes were found in 7.5% of the non-enterococci, including the genera Pediococcus (12.5%) and Weissella (6.7%). One strain of both Pediococcus pentosaceus and Weissella cibaria carried the erythromycin resistance gene mef(A/E), and another two P. pentosaceus strains harboured lnu(A) conferring resistance to lincosamides. Gelatinase activity was found in E. faecalis and E. faecium (71 and 11%, respectively), while a low number of E. faecalis (5%) and none E. faecium exerted hemolytic activity. None enterococci and non-enterococci showed bile deconjugation and mucin degradation abilities, or other detrimental enzymatic activities. Conclusions To our knowledge, this is the first description of mef(A/E) in the genera Pediococcus and Weissella, and lnu(A) in the genus Pediococcus. The in vitro subtractive screening presented in this work constitutes a valuable strategy for the large-scale preliminary selection of putatively safe LAB

Diseño de dos metodologías moleculares para la rápida identificación de aislamientos de Staphylococcus aureus resistente a meticilina asociados a la comunidad en Colombia

OpenAIRE

Javier Antonio Escobar; Ingrid Tatiana Gómez; Martha Johanna Murillo; Betsy Esperanza Castro; Bibiana Chavarro; Ricaurte Alejandro Márquez; Natasha Vanegas

2012-01-01

Introducción. Los aislamientos de Staphylococcus aureus resistente a la meticilina asociado a la comunidad (SARM-AC), están aumentando la frecuencia de infecciones en personas sanas de la comunidad y en pacientes hospitalizados. En Colombia y en la región andina estos aislamientos tienen un componente genético relacionado con el clon pandémico USA300. Objetivo. Diseñar y estandarizar dos metodologías para la diferenciación rápida de aislamientos colombianos de S. aureus resistente a la me...

Controle de plantas daninhas na cultura de soja resistente ao glyphosate

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Núbia Maria Correia

2010-01-01

Full Text Available O objetivo da pesquisa foi avaliar o controle de plantas daninhas em área cultivada com soja resistente ao herbicida glyphosate, sem a utilização de práticas complementares de manejo de plantas daninhas. Foram desenvolvidos experimentos, em condições de campo, nos anos agrícolas 2005/2006 e 2006/2007 em Jaboticabal (SP. Foram avaliadas duas cultivares de soja resistentes ao glyphosate (CD 214 RR e M-SOY 8008 RR, oito tratamentos de herbicidas (glyphosate, em aplicação única, nas doses de 0,48; 0,72; 0,96 e 1,20 kg ha-1 de equivalente ácido, associadas ou não a aplicação sequencial na dose de 0,48 kg ha-1, além de duas testemunhas, uma capinada e outra mantida infestada. As cultivares de soja influenciaram na infestação das espécies de plantas daninhas na área. Sem a aplicação de glyphosate, houve o predomínio de X. strumarium na área, desfavorecendo a ocorrência de outras espécies. Quando utilizado glyphosate, independentemente da dose, a infestação contabilizada aos 35 e 40 dias após a primeira aplicação, no primeiro e segundo ano, respectivamente, foi baixa. O controle de plantas daninhas na cultura da soja transgênica é diretamente influenciado pela dose de glyphosate, havendo controle satisfatório com a aplicação única de 0,96 kg ha-1 ou a sequencial de 0,48 + 0,48 kg ha-1 de glyphosate. Em situação de menor infestação (2006/2007, a aplicação única de 0,48 kg ha-1 de glyphosate é suficiente para o controle das plantas daninhas. As cultivares de soja transgênica CD 214 RR e M-SOY 8008 RR influenciam diferencialmente a dinâmica das espécies de plantas daninhas, sendo o controle químico mais efetivo na situação de cultivo de M-SOY 8008 RR, em que houve menor diversidade e desenvolvimento das plantas daninhas.

Denervação Renal com Cateter Irrigado em Hipertensos Resistentes: Uma Estratégia Promissora?

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Luciana Armaganijan

2014-04-01

Full Text Available Fundamento: A hipertensão arterial sistêmica constitui importante problema de saúde pública e significativa causa de mortalidade cardiovascular. A elevada prevalência e as reduzidas taxas de controle tensional despertaram o interesse por estratégias terapêuticas alternativas. A denervação simpática renal percutânea surgiu como perspectiva no tratamento de hipertensos resistentes. Objetivo: Avaliar a factibilidade e a segurança da denervação renal com cateter irrigado. Métodos: Dez hipertensos resistentes foram submetidos ao procedimento. O desfecho primário foi a segurança, avaliada por eventos adversos periprocedimento, função renal e anormalidade vascular renal aos 6 meses. Os desfechos secundários constituíram mudanças na pressão arterial (consultório e monitorização ambulatorial e no número de anti-hipertensivos aos 6 meses. Resultados: A média de idade foi de 47,3 (± 12 anos, 90% eram mulheres. No primeiro caso, houve dissecção de artéria renal causada por trauma da bainha, fato que não se repetiu após ajuste técnico, demonstrando efeito da curva de aprendizado. Nenhum caso de trombose/infarto renal ou óbito foi reportado. Não se observou elevação dos níveis séricos de creatinina durante o seguimento. Aos 6 meses, diagnosticou-se um caso de estenose significativa de artéria renal, sem repercussão clínica. A denervação renal reduziu a pressão arterial de consultório, em média, em 14,6/6,6 mmHg (p = 0,4 tanto para pressão arterial sistólica como para a diastólica. A redução média da pressão arterial pela monitorização ambulatorial foi de 28/17,6 mmHg (p = 0,02 e p = 0,07 para pressão arterial sistólica e diastólica, respectivamente. Houve redução média de 2,1 anti-hipertensivos. Conclusão: A denervação renal é factível e segura no tratamento da hipertensão arterial sistêmica resistente. Estudos maiores são necessários para confirmar nossos resultados.

Human health risks associated with antimicrobial-resistant enterococci and Staphylococcus aureus on poultry meat

DEFF Research Database (Denmark)

Bortolaia, V.; Gongora, Carmen Espinosa; Guardabassi, L.

2016-01-01

health risks associated with the occurrence of these opportunistic human pathogens on poultry meat with particular focus on the risk of food-borne transmission of antimicrobial resistance. In the absence of conclusive evidence of transmission, this risk was inferred using data from scientific articles......-resistant S. aureus of livestock origin has been reported on poultry meat. In theory handling or ingestion of contaminated meat is a potential risk factor for colonization by methicillin-resistant S. aureus. However, this risk is presently regarded as negligible by public health authorities. Clinical......Enterococci and staphylococci are frequent contaminants on poultry meat. Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus are also well-known aetiological agents of a wide variety of infections resulting in major healthcare costs. This review provides an overview of the human...

Antimicrobial-resistant bacteria in wild game in Slovenia

Science.gov (United States)

Križman, M.; Kirbiš, A.; Jamnikar-Ciglenečki, U.

2017-09-01

Wildlife is usually not exposed to clinically-used antimicrobial agents but can acquire antimicrobial resistance throughout contact with humans, domesticated animals and environments. Samples of faeces from intestines (80 in total) were collected from roe deer (52), wild boars (11), chamois (10) red deer (6) and moufflon (1). After culture on ChromID extended spectrum β-lactamase (ESBL) plates to select for growth of ESBL-producing bacteria, 25 samples produced bacterial colonies for further study. Six species of bacteria were identified from the 25 samples: Stenotrophomonas maltophilia, Serratia fonticola, Stenotrophomonas nitritireducens, Enterococcus faecium, Enterococcus faecalis and Escherichia coli. Two ESBL enzymes were amplified from group TEM and three from group CTX-M-1. Undercooked game meat and salami can be a source of resistant bacteria when animals are not eviscerated properly.

Antibiotic resistance in animals.

Science.gov (United States)

Barton, Mary D; Pratt, Rachael; Hart, Wendy S

2003-01-01

There is currently no systematic surveillance or monitoring of antibiotic resistance in Australian animals. Registration of antibiotics for use in animals is tightly controlled and has been very conservative. Fluoroquinolones have not been registered for use in food producing animals and other products have been removed from the market because of human health concerns. In the late 1970s, the Animal Health Committee coordinated a survey of resistance in Salmonella and Escherichia coli isolates from cattle, pigs and poultry and in bovine Staphylococcus aureus. Some additional information is available from published case reports. In samples collected prior to the withdrawal of avoparcin from the market, no vancomycin resistant Enterococcus faecium or Enterococcus faecalis were detected in samples collected from pigs, whereas some vanA enterococci, including E. faecium and E. faecalis, were found in chickens. No vanB enterococci were detected in either species. Virginiamycin resistance was common in both pig and poultry isolates. Multiple resistance was common in E. coli and salmonellae isolates. No fluoroquinolone resistance was found in salmonellae, E. coli or Campylobacter. Beta-lactamase production is common in isolates from bovine mastitis, but no methicillin resistance has been detected. However, methicillin resistance has been reported in canine isolates of Staphylococcus intermedius and extended spectrum beta-lactamase producing E. coli has been found in dogs.

Growth of Enterococcus durans E204 producing bacteriocin-like ...

African Journals Online (AJOL)

Bacteriocin-like substance E204 is an antimicrobial compound produced by Enterococcus durans E204 isolated from camel milk of Morocco that shows a broad spectrum of inhibitory activity against taxonomically related microorganisms. It is sensitive to digestive proteases. In the first study, de Man, Regosa and Sharpe ...

PHYSICHOCHEMICAL CHACTERIZATION OF BACTERIOCIN PRODUCING ENTEROCOCCUS DURANS ISOLATED FROM COLON’S BALI CATTLE

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I Wayan Suardana

2017-08-01

Full Text Available Lactic acid bacteria can excrete antimicrobial compounds like bacteriocins. The study  aimed  to  find  out  the  characteristic  of  physic-chemical  of  bacteriocin  producing Enterococcus durans          isolate 18A isolated from  colon’s bali cattle. The study initiated by Gram staining and catalase test, followed by isolation and purification  of bacteriocin.       The result of the research showed  that bacteriocins of    Enterococcus durans    isolate 18A as a protein with it’s concentrationis  0,272?g/ml  and  it  does  not  contain  carbohydrate.  On  the  other  hand,  the bacteriocins was not showed a band while tested on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE. The result showed, the bacteriocin producing            Enterococcus durans isolate 18A has antimicrobial activity to Bacillus cereus  as 23,88%.

WATERMARK RESISTENTE EN EL DOMINIO DE LAS FRECUENCIAS DE IMÁGENES DIGITALES PARA SU AUTENTICACIÓN SEGURA MEDIANTE AUTÓMATAS CELULARES

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Luz Fátima Huallpa Vargas

2011-01-01

Full Text Available En este trabajo se presenta el desarrollo de un procedimiento de autenticación de imágenes digitales combinando diversos métodos relacionados con watermarks (marcas de agua digitales y métodos de cifrado, con el fin de proteger los derechos de autor de imágenes digitales. Para que este procedimiento sea robusto, imperceptible y resistente a diferentes ataques intencionales o no intencionales se trabaja en el dominio de las frecuencias de la imagen utilizando la Transformada Discreta del Coseno (Discrete Cosine Transform, DCT. Para agregar mayor nivel de protección y seguridad a la imagen marcada, se cifra el mensaje insertado a partir de una clave del autor empleando el método de Autómatas Celulares. El mensaje insertado es resistente a la compresión JPEG, a los ruidos y filtros gaussiano y salt-and-pepper. La extracción del mensaje se realiza a partir de la imagen marcada para lo cual se hace uso estricto de la clave del autor para verificar la autenticidad del mismo.

Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

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Luciane Cristina Gelatti

2009-08-01

Full Text Available Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticilina adquirido na comunidade no Sul do Brasil. O paciente foi atendido em Unidade de Emergência com história de ferimento provocado por trauma em membro inferior que evoluiu para celulite, pneumonia e sepse.Methicillin-resistant Staphylococcus aureus was initially described as a typical microorganism acquired in nosocomial infections. However, over recent years, community-acquired methicillin-resistant Staphylococcus aureus has been a cause of skin and soft-tissue infections. Serious infections such as pneumonia and sepsis can also occur. This report describes a case of sepsis in a child that was complicated by pneumonia secondary to soft tissue lesions that were due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil. The patient was attended at the Emergency Unit with a history of injury caused by lower-limb trauma that evolved to cellulitis, pneumonia and sepsis.

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

NARCIS (Netherlands)

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

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 Ramon y Cajal University Hospital (Madrid, Spain) from the community and with no overlapping stay during a 10-month

Bacteriological research for the contamination of digital portable radiography

Energy Technology Data Exchange (ETDEWEB)

Shin, Seong Gyu [Dept. of Radiology, Dong A University Hospital, Busan (Korea, Republic of); Lee, Hyo Yeong [Dept. of Radiological Science, Dong Eui University, Busan (Korea, Republic of)

2017-03-15

The study was performed to investigate the bacteriological contamination of portable digital radiography system and their detectors in a university hospital. CNS and VRE were detected in the samples collected from vinyl cover on detectors used for the infection control patients. On the other hand, no bacteria was detected in the samples collected from detectors with vinyl cover removed. In the series of imaging of patients from general wards, no bacteria was detected from the patient 1. However, CNS was detected from the patients 2 and 3, CNS and Enterococcus faecalis detected from the patient 4, CNS and Enterococcus casseliflavus detected from the patient 5, and CNS, Enterococcus casseliflavus, and Klebsiella pneumoniae all detected from the patient 6. CNS and Enterococcus faecium were detected in the controller handle of collimator. Also, CNS was detected from the handle of detector and exposure switch. In the treatment gloves of the radiological technologist after the imaging, CNS, Enterococcus gallinarum, and Klebsiella pneumoniae were detected. Therefore, it is recommended for DR portable to take images after sterilizing the detector after taking each image and to use disposable vinyl covers on detectors to remove after imaging. And treatment gloves must be changed after each imaging. Also, hospital infection via portables must be prevented by complete sterilization of the controller handles of collimator which are in frequent contact during imaging and infection education of employees.

Obtenção de plantas de feijão-caupi resistentes ao Cowpea severe mosaic virus e ao Cowpea aphid-borne mosaic virus

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Gislanne Brito Barros

2013-06-01

Full Text Available Dentre os vírus que infectam o feijão-caupi (Vigna unguiculata L. Walp. destacam-se, respectivamente, pela severidade e ampla ocorrência o Cowpea severe mosaic virus (CPSMV e o Cowpea aphid-borne mosaic virus (CABMV. Portanto, objetivaram-se, no presente trabalho, obter e avaliar plantas de feijão-caupi com resistência ao CPSMV e ao CABMV, visando ao desenvolvimento de cultivares essencialmente derivadas e novas cultivares. Realizaram-se oito cruzamentos seguidos de retrocruzamentos, utilizando a linhagem TE 97-309G-9 e a cultivar Patativa como genitores resistentes, e as cultivares BR3-Tracuateua, BRS-Urubuquara, BRS-Novaera, BRS-Guariba e Pretinho como genitores suscetíveis. As gerações F2 e F2RC1 foram desafiadas quanto à resistência por meio de inoculação mecânica com isolados do CPSMV e do CABMV. Nas gerações F2RC1, além da resistência foram avaliados os caracteres: número de dias para o início da floração, comprimento das vagens, número de grãos. vagem-1, peso de cem grãos e produção de grãos.planta-1. Todos os indivíduos F2 e F2RC1 foram analisados pelo teste χ² e se ajustaram à frequência esperada de 15 plantas suscetíveis 1 planta resistente a ambos os vírus. As médias das plantas F2RC1 resistentes, de cada retrocruzamento, foram comparadas com a média do seu respectivo genitor recorrente pelo teste 't' e as médias dos retrocruzamentos foram comparadas pelo teste de Scott-Knott. Foi detectada variabilidade genética entre os retrocruzamentos para todos os caracteres. Todos os retrocruzamentos foram considerados promissores para produção de cultivares essencialmente derivadas resistentes ao CPSMV e ao CABMV e as plantas selecionadas possuem características que possibilitam a seleção de linhagens com grãos de bom padrão comercial e altamente produtivas.

In vitro inhibition of Eimeria tenella sporozoite invasion into host cells by probiotics.

Science.gov (United States)

Hessenberger, S; Schatzmayr, G; Teichmann, K

2016-10-15

The aim was to study the effects of probiotics isolated from the intestinal tract of livestock animals on Eimeria tenella invasion into Madin-Darby bovine kidney (MDBK) cells in vitro. E. tenella sporozoites were purified and labeled with 5(6)-carboxyfluorescein diacetate N-succinimidyl ester before seeding on cell cultures, and invasion was evaluated by fluorescence microscopy. Two protocols (A and B) were used. In protocol A, Enterococcus faecium # 589 or Lactobacillus salivarius subsp. salivarius # 505 were added together with sporozoites to MDBK cell cultures and invasion was evaluated after incubation for approximately 20h. Viable, dead, or spent culture supernatants of probiotics were tested. In protocol B, viable probiotics were incubated with MDBK cells for one hour before sporozoites were added and invasion was evaluated after two more hours of incubation. Parasite invasion of viable, dead, or spent culture supernatant of E. faecium # 589 was assessed. Using protocol A, it was shown that parasite invasion was inhibited by viable (80%) or dead (75%) E. faecium # 589. While inhibition by viable L. salivarius subsp. salivarius # 505 was not valid at the highest concentration and not significant at the other test concentrations, dead cells inhibited parasite invasion up to 45%. Spent culture supernatants of both probiotics had no influence on parasite invasion. Using protocol B, it was shown that viable Bifidobacterium animalis subsp. animalis # 503, E. faecium # 497, E. faecium # 589, L. reuteri # 514, L. salivarius subsp. salivarius # 505, and Bacillus subtilis # 588 inhibited parasite invasion into MDBK cells up to 80%. Anticoccidial activity was strain-specific for E. faecium strains, and the strongest effect was shown by E. faecium # 589. Anticoccidial effects of some of the tested probiotics have already been shown in vivo, which makes them candidates to prevent coccidiosis. These findings have now been confirmed in vitro. The used parasite invasion

Bacterial Flora Changes in Conjunctiva of Rats with Streptozotocin-Induced Type I Diabetes.

Science.gov (United States)

Yang, Chao; Fei, Yuda; Qin, Yali; Luo, Dan; Yang, Shufei; Kou, Xinyun; Zi, Yingxin; Deng, Tingting; Jin, Ming

2015-01-01

The microbiota of both humans and animals plays an important role in their health and the development of disease. Therefore, the bacterial flora of the conjunctiva may also be associated with some diseases. However, there are no reports on the alteration of bacterial flora in conjunctiva of diabetic rats in the literature. Therefore, we investigated the changes in bacterial flora in bulbar conjunctiva of rats with streptozotocin (STZ)-induced type I diabetes. A high dose of STZ (60 mg/kg, i.p.) was injected into Sprague-Dawley (SD) rats to induce type I diabetes mellitus (T1DM). The diabetic rats were raised in the animal laboratory and at 8 months post-injection of STZ swab samples were taken from the bulbar conjunctiva for cultivation of aerobic bacteria. The bacterial isolates were identified by Gram staining and biochemical features. The identified bacteria from both diabetic and healthy rats were then compared. The diabetic and healthy rats had different bacterial flora present in their bulbar conjunctiva. In total, 10 and 8 bacterial species were found in the STZ and control groups, respectively, with only three species (Enterococcus faecium, Enterococcus gallinarum and Escherichia coli) shared between the two groups. Gram-positive bacteria were common in both groups and the most abundant was Enterococcus faecium. However, after the development of T1DM, the bacterial flora in the rat bulbar conjunctiva changed considerably, with a reduced complexity evident. STZ-induced diabetes caused alterations of bacterial flora in the bulbar conjunctiva in rats, with some bacterial species disappearing and others emerging. Our results indicate that the conjunctival bacterial flora in diabetic humans should be surveyed for potential diagnostic markers or countermeasures to prevent eye infections in T1DM patients.

Caracterización morfológica y contenido de almidón resistente y disponible en bananos (Musa sapientum exportables del Ecuador

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Edison Omar Martínez-Mora

2015-10-01

Full Text Available Introducción: La investigación tuvo como objetivo fundamental, la caracterización morfológica del almidón nativo de banano (Musa sapientum, contenido en almidón resistente (AR y disponible (AD, de las variedades de banano de exportación: Cavendish (AC, Filipino (AF, Orito (AO y Valery (AV.Material y Métodos: Se determinó tamaño y forma del gránulo de almidón a través de microscopia electrónica de barrido. La cuantificación del AR por medición de su fracción no hidrolizada, luego de un ataque de pepsina, y para la fracción del AD un ataque de amilasa pancreática a la fracción no hidrolizada. Se midió la absorbancia de las dos soluciones de AR y AD a 510nm contra el blanco del reactivo.Resultados: El tamaño de los gránulos de almidón de: AF, AV y AC fueron en promedio 28μm y para el AO, de 35μm aproximadamente. La forma que predominó fue la oval esférica. El contenido de AR y AD estuvo en el rango de 49 a 58,5% y de 41 a 50%, respectivamente.Conclusiones: El almidón resistente, análogo de la fibra y útil en la nutrición humana, se presentó en valores importantes en las muestras de las diferentes variedades de banano exportable del Ecuador, alrededor del 54%. Según los resultados, el almidón de banano de las variedades estudiadas puede ser incorporado en la elaboración de alimentos que demanden características funcionales, principalmente por su alto contenido en almidón resistente.

Denervación renal percutánea mediante el uso de catéter con balón en pacientes con hipertensión arterial resistente

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Isabel C. Marín-Orozco

2015-11-01

El objetivo del presente reporte es describir detalladamente dos casos de hipertensión arterial resistente, tratados mediante ablación con radiofrecuencia con el nuevo dispositivo Vessix® de la compañía Boston Scientific.

Risk Factors of Endocarditis in Patients with Enterococcus faecalis Bacteremia

DEFF Research Database (Denmark)

Dahl, Anders; Lauridsen, Trine K; Arpi, Magnus

2016-01-01

BACKGROUND:  The NOVA score is a recently developed diagnostic tool to identify patients with increased risk of infective endocarditis (IE) among patients with Enterococcus faecalis (EF) bacteremia. We aim to validate an adapted version of the NOVA score and to identify risk factors for IE...

AMIDO RESISTENTE EM FARINHAS DE BANANA VERDE

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Dayana Portes RAMOS

2010-03-01

Full Text Available

Este trabalho teve por objetivo avaliar o teor de amido resistente (AR em farinhas de banana verde produzidas a partir de treze genótipos de bananeira. Para a produção da farinha foram separadas a 1ª, 3ª e 5ª pencas de cada genótipo, na qual cada penca correspondeu a uma repetição. Os frutos de cada penca no estádio 1 (casca completamente verde de maturação foram descascados manualmente, cortados em fatias circulares de 0,5 cm e desidratados em estufa com circulação de ar a 40ºC por 48 horas, sendo em seguida moídos. A análise de AR consistiu em um processo enzimático, calculando-se o conteúdo final pela concentração de glicose liberada. Os resultados foram submetidos à análise estatística e mostraram diferenças significativas para o teor de AR nas farinhas obtidas dos genótipos de bananeira, sendo que a farinha com maior teor de AR foi a produzida a partir do cultivar ‘Nam’ (40,25% e a menor pelo híbrido ‘Fhia 01’ (10,01%. Pode-se concluir que o conteúdo de AR varia em relação ao genótipo utilizado para a confecção da farinha e que a banana pode ser uma boa opção de estudo de alimento funcional.

Antibacterial effect of four endodontic cements against Enterococcus faecalis ATCC 29212. An in vitro study.

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Marcos J. Carruitero

2017-12-01

Full Text Available Objective: To compare the in vitro antibacterial effect of the root canal cements Endobalsam®, Top Seal®, Apexit® and Endofill® against Enterococcus faecalis ATCC 29212. Materials and method: Eighty-five applications of cements on Enterococcus faecalis, cultured in vitro on solid media in Petri dishes, were analyzed. Five groups were evaluated: four for each cement, and the fifth for the positive control (amoxicillin. The antibacterial effect was measured by the diameters of the bacterial inhibition halos at 24 hours, 48 hours, and seven days. Student´s t-test, ANOVA and the Tukey test were used for the statistical analysis. Results: No statistically significant differences were found at 24 hours (p>0.05; at 48 hours and seven days, Endofill® and Apexit® had the greatest effect (p0.05. Conclusion: Enterococcus faecalis ATCC 29212 was susceptible to all cements. Endofill® had greater in vitro antibacterial effect than Apexit®, Top Seal® and Endobalsam®.

Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

Science.gov (United States)

Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

2016-01-01

Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

Isolation of cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and molecular comparison with dairy-related Lactobacillus helveticus strains

DEFF Research Database (Denmark)

Jensen, Marie Elisabeth Penderup; Ardö, Ylva Margareta; Vogensen, Finn Kvist

2009-01-01

-related Lact. helveticus strains indicated that one isolate was a Lact. helveticus. Partial sequencing of 16S rRNA confirmed this, and the remaining four strains were identified as Lactobacillus delbrueckii, Lactobacillus fermentum and Enterococcus faecium. The rep-PCR profile of the isolated Lact. helveticus......Aims: To isolate cultivable thermophilic lactic acid bacteria from cheeses made with mesophilic starter and compare them with dairy-related Lactobacillus helveticus strains using molecular typing methods. Methods and Results: The number of thermophilic bacteria in seven commercial cheeses...

Enterocin T, a novel class IIa bacteriocin produced by Enterococcus sp. 812.

Science.gov (United States)

Chen, Yi-Sheng; Yu, Chi-Rong; Ji, Si-Hua; Liou, Min-Shiuan; Leong, Kun-Hon; Pan, Shwu-Fen; Wu, Hui-Chung; Lin, Yu-Hsuan; Yu, Bi; Yanagida, Fujitoshi

2013-09-01

Enterococcus sp. 812, isolated from fresh broccoli, was previously found to produce a bacteriocin active against a number of Gram-positive bacteria, including Listeria monocytogenes. Bacteriocin activity decreased slightly after autoclaving (121 °C for 15 min), but was inactivated by protease K. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 4,521.34 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2-ATYYGNGVYXDKKKXWVEWGQA, by Edman degradation, which contained the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The obtained partial sequence showed high homology with some enterococcal bacteriocins; however, no identical peptide or protein was found. This peptide was therefore considered to be a novel bacteriocin produced by Enterococcus sp. 812 and was termed enterocin T.

Changes in human fecal microbiota due to chemotherapy analyzed by TaqMan-PCR, 454 sequencing and PCR-DGGE fingerprinting.

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Jutta Zwielehner

Full Text Available BACKGROUND: We investigated whether chemotherapy with the presence or absence of antibiotics against different kinds of cancer changed the gastrointestinal microbiota. METHODOLOGY/PRINCIPAL FINDINGS: Feces of 17 ambulant patients receiving chemotherapy with or without concomitant antibiotics were analyzed before and after the chemotherapy cycle at four time points in comparison to 17 gender-, age- and lifestyle-matched healthy controls. We targeted 16S rRNA genes of all bacteria, Bacteroides, bifidobacteria, Clostridium cluster IV and XIVa as well as C. difficile with TaqMan qPCR, denaturing gradient gel electrophoresis (DGGE fingerprinting and high-throughput sequencing. After a significant drop in the abundance of microbiota (p = 0.037 following a single treatment the microbiota recovered within a few days. The chemotherapeutical treatment marginally affected the Bacteroides while the Clostridium cluster IV and XIVa were significantly more sensitive to chemotherapy and antibiotic treatment. DGGE fingerprinting showed decreased diversity of Clostridium cluster IV and XIVa in response to chemotherapy with cluster IV diversity being particularly affected by antibiotics. The occurrence of C. difficile in three out of seventeen subjects was accompanied by a decrease in the genera Bifidobacterium, Lactobacillus, Veillonella and Faecalibacterium prausnitzii. Enterococcus faecium increased following chemotherapy. CONCLUSIONS/SIGNIFICANCE: Despite high individual variations, these results suggest that the observed changes in the human gut microbiota may favor colonization with C. difficile and Enterococcus faecium. Perturbed microbiota may be a target for specific mitigation with safe pre- and probiotics.

The antimicrobial susceptibility profile of ESKAPE pathogens from urinary tract infections in a referral laboratory, Northeast Iran

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Mohammad Salehi

2016-11-01

Full Text Available Objective: To assess the antimicrobial susceptibility pattern of ESKAPE pathogens from Neyshabur, Iran during 2013–2015. Methods: A total of 345 isolates including 62 Staphylococcus aureus (S. aureus, 38 Enterobacter spp. (including 14 Enterobacter agglomerans, 6 Enterobacter aerogenes and other 18 Enterobacter spp., 123 Enterococcus faecium, 78 Klebsiella pneumonia, 10 Pseudomonas aeruginosa and 34 Acinetobacter baumannii were isolated. The antimicrobial susceptibility pattern of isolates was conducted with Kirby Bauer method. Data were analyzed with SPSS 20.0 software using F- and t-tests. Results: Among S. aureus isolates, the highest resistance was observed against nalidixic acid (81.35% and cefixime (74.50%. Thirty-three (53.22% S. aureus isolates were cefoxitin resistant (methicillin-resistant S. aureus. The majority of Enterobacter species was resistant to amikacin (100.00% and cephalotin (66.60%. Most Enterococcus faecium isolates were resistant to nalidixic acid (89.43% and amikacin (83.33%, but vancomycin-resistant enterococci isolates were not detected. Moreover, among Klebsiella pneumonia, the highest resistance was observed to nalidixic acid (20.98% and cotrimoxazole (28.39%. Furthermore, all Pseudomonas aeruginosa isolates were resistant to cefotaxime (100.00% and majority to nitroforantoin (88.80%. Acinetobacter baumannii isolates showed the highest and the lowest resistance to cefotaxime (100.00% and cefixime (88.71%, respectively. Conclusions: The prevalence of ESKAPE pathogens from northeast region was low, but majority of them exhibited high rate of antibiotic resistance to common used antimicrobial agents.

Comparison of the loads and antibiotic-resistance profiles of Enterococcus species from conventional and organic chicken carcasses in South Korea.

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Kim, Y-J; Park, J-H; Seo, K-H

2018-01-01

Antibiotic-resistant bacteria in poultry meat are a threat to public health. In this study, we compared the Enterococcus spp. loads and antibiotic-resistance profiles between carcasses of conventionally and organically raised chickens. A total of 144 chicken carcasses (72 conventional and 72 organic) was collected from local retail markets in Seoul, South Korea. Overall, 77.7% (112 of 144; 75% conventional and 80% organic) of chicken carcasses were positive for Enterococcus. The mean loads of Enterococcus spp. were greater in conventional chicken carcasses, at 2.9 ± 0.4 log CFU/mL, than those in organic chicken carcasses, at 1.78 ± 0.3 log CFU/mL (p organic chicken carcasses) was randomly selected for further analysis. The predominant species was Enterococcus faecalis in both conventional and organic chicken carcasses (57.7 and 76.9%, respectively; P > 0.05). Rates of resistance to ciprofloxacin and erythromycin, which are used in veterinary medicine in South Korea, were significantly higher in conventional chicken carcasses than in organic chicken carcasses. However, we found no difference between the rates of resistance to antibiotics such as vancomycin and tigecycline, which were not registered for use in veterinary medicine in South Korea, of Enterococcus isolates from conventional and organic chicken carcasses. In addition, although multidrug resistant isolates were obtained from both types of chicken samples, the prevalence of samples positive for Enterococcus was significantly higher in conventional chicken carcasses than in organic chicken carcasses (P organic chicken carcasses. A high level of gentamicin resistance was observed in isolates from not only conventional (5.8%) but also organic chicken (1.9%) carcasses, with no significant difference in rates between them (P > 0.05). Despite this, our results suggest that organic food certification is effective in reducing fecal contamination and the burden of antibiotic-resistant Enterococcus spp. in

Fluoroquinolone susceptibilities to methicillin-resistant and susceptible coagulase-negative Staphylococcus isolated from eye infection Suscetibilidade dos Staphylococcus coagulase negativo meticilina-resistentes e suscetíveis isolados em infecções oculares

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Adália Dias Dourado Oliveira

2007-03-01

Full Text Available PURPOSE: To evaluate the fluoroquinolone susceptibilities of ocular isolate coagulase-negative staphylococci (CoNS, identified at the Microbiology Laboratory - UNIFESP. DESIGN: Experimental laboratory investigation. METHODS: The minimum inhibitory concentrations (MICs of 21 strains of methicillin-resistant coagulase-negative staphylococci (MRCoNS and 22 methicillin-sensitive coagulase-negative staphylococci (MSCoNS to ciprofloxacin, ofloxacin, gatifloxacin and moxifloxacin were determined, using the E-test method standardized by the Clinical and Laboratory Standards Institute (CLSI/NCCLS. RESULTS: The MIC90s (µg/ml for the second generation of tested fluoroquinolones were higher than the fourth generation, especially for the methicillin-resistant coagulase-negative staphylococci group. CONCLUSION: Our results indicate that methicillin-sensitive coagulase-negative staphylococci are more susceptible to quinolones than are methicillin-resistant coagulase-negative staphylococci and that fourth generation fluoroquinolones appear to be more potent, affecting even coagulase-negative staphylococcal strains resistant to second generation fluoroquinolones.OBJETIVOS: Avaliar a suscetibilidade a fluorquinolonas dos Staphylococcus coagulase-negativo (SCoN identificados no Laboratório de Microbiologia Ocular da Unifesp. MÉTODOS: Foi determinada a concentração inibitória mínima de 21 cepas de SCoN meticilina-resistentes e 22 meticilina-sensíveis para ciprofloxacina, ofloxacina, gatifloxacina e moxifloxacina, utilizando o E-test estandartizado pelo CLSI/NCCLS. RESULTADOS: Os MIC90 (µg/ml de 43 SCoN isolados para fluorquinolonas de segunda geração foram maiores do que os de quarta geração, principalmente para o grupo dos meticilina-resistentes. CONCLUSÃO: Nossos resultados indicam que Staphylococcus coagulase-negativo meticilina-sensíveis são mais suscetíveis às quinolonas do que os Staphylococcus coagulase-negativo meticilina-resistentes

Sample preparation methods for quantitative detection of DNA by molecular assays and marine biosensors.

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Cox, Annie M; Goodwin, Kelly D

2013-08-15

The need for quantitative molecular methods is growing in environmental, food, and medical fields but is hindered by low and variable DNA extraction and by co-extraction of PCR inhibitors. DNA extracts from Enterococcus faecium, seawater, and seawater spiked with E. faecium and Vibrio parahaemolyticus were tested by qPCR for target recovery and inhibition. Conventional and novel methods were tested, including Synchronous Coefficient of Drag Alteration (SCODA) and lysis and purification systems used on an automated genetic sensor (the Environmental Sample Processor, ESP). Variable qPCR target recovery and inhibition were measured, significantly affecting target quantification. An aggressive lysis method that utilized chemical, enzymatic, and mechanical disruption enhanced target recovery compared to commercial kit protocols. SCODA purification did not show marked improvement over commercial spin columns. Overall, data suggested a general need to improve sample preparation and to accurately assess and account for DNA recovery and inhibition in qPCR applications. Published by Elsevier Ltd.

Isolation, enumeration, molecular identification and probiotic potential evaluation of lactic acid bacteria isolated from sheep milk

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L.B. Acurcio

2014-06-01

Full Text Available Lactic acid bacteria species were molecularly identified in milk from Lacaune, Santa Inês and crossbred sheep breeds and their in vitro probiotic potential was evaluated. The species identified were Enterococcus faecium (56.25%, E. durans (31.25% and E. casseliflavus (12.5%. No other lactic acid bacteria species, such as lactobacilli, was identified. Most of the isolated enterococci were resistant to gastric pH (2.0 and to 0.3% oxgall. All tested enterococci were resistant to ceftazidime, oxacillin and streptomycin and sensible to clindamycin, erythromycin and penicillin. The resistance to ciprofloxacin, gentamicin, tetracycline and vancomycin varied among tested species. All tested enterococci strongly inhibited (P<0.05 Escherichia coli and Listeria monocytogenes, moderately inhibited E. faecalis and Staphylococcus aureus and did not inhibit Pseudomonas aeruginosa, Salmonella enterica var. Typhimurium and also one E. durans sample isolated from sheep milk. Four samples of E. faecium, one of E. durans and one of E. casseliflavus presented the best probiotic potential.

Physiological characterization of Enterococcus faecalis during azoreductase activity

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Punj, Sumit; John, Gilbert H.

2011-01-01

Azo dyes are widely used in the food, pharmaceutical, paper, and textile industries. Some azo dyes are known to produce carcinogenic compounds upon reductive cleavage of the azo bond (N=N) by intestinal flora. There is not much information available on the effect of these dyes on the physiology of the gut microflora as well as their kinetics of reduction in different environments. The azoreductase activity of Enterococcus faecalis, an important opportunistic intestinal pathogen, was tested us...

Molecular analysis and dimorphism of azole-susceptible and resistant Candida albicans isolates Análise molecular e dimorfismo de isolados de Candida albicans suscetíveis e resistentes aos azólicos

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Carolina Rodrigues Costa

2011-12-01

estudo, os efeitos de agentes antifúngicos como o fluconazol e o itraconazol sobre a formação de hifas e caracterização genotípica de isolados de C. albicans suscetíveis ou resistentes foram investigados. MÉTODOS: A produção de hifas de cinco isolados de C. albicans, sob a ação de antifúngicos foi investigada pelo cultivo da levedura em meios de crescimento e de indução de hifas. A caracterização genotípica foi realizada para 13 isolados de C. albicans pelo método de RAPD-PCR. RESULTADOS: A análise do dimorfismo mostrou que a formação de hifas foi maior nos isolados resistentes do que nos suscetíveis aos antifúngicos. O método de RAPD-PCR identificou a formação de dois diferentes grupos. No grupo A, foram agrupados quatro isolados resistentes e dois suscetíveis e no grupo B um resistente e seis suscetíveis. CONCLUSÕES: Considerando que a formação hifal foi maior em isolados resistentes na presença de azólicos, concluimos que a produção hifal está muito relacionada a suscetibilidade a estes fámacos. Estes antifúngicos podem alterar a morfologia de C. albicans em dependência da sua suscetibilidade. No método de RAPD-PCR, o encontro da maioria dos isolados resistentes classificados como pertencentes ao grupo A e suscetíveis ao grupo B demonstrou que este método apresentou um padrão semelhante entre os dois grupos, sugerindo que por este método pode ser detectado uma estreita correlação entre genótipos e amostras resistentes ao fluconazol.

Daptomycin resistance in enterococci is associated with distinct alterations of cell membrane phospholipid content.

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Nagendra N Mishra

Full Text Available The lipopeptide antibiotic, daptomycin (DAP interacts with the bacterial cell membrane (CM. Development of DAP resistance during therapy in a clinical strain of Enterococcus faecalis was associated with mutations in genes encoding enzymes involved in cell envelope homeostasis and phospholipid metabolism. Here we characterized changes in CM phospholipid profiles associated with development of DAP resistance in clinical enterococcal strains.Using two clinical strain-pairs of DAP-susceptible and DAP-resistant E. faecalis (S613 vs. R712 and E. faecium (S447 vs. R446 recovered before and after DAP therapy, we compared four distinct CM profiles: phospholipid content, fatty acid composition, membrane fluidity and capacity to be permeabilized and/or depolarized by DAP. Additionally, we characterized the cell envelope of the E. faecium strain-pair by transmission electron microscopy and determined the relative cell surface charge of both strain-pairs.Both E. faecalis and E. faecium mainly contained four major CM PLs: phosphatidylglycerol (PG, cardiolipin, lysyl-phosphatidylglycerol (L-PG and glycerolphospho-diglycodiacylglycerol (GP-DGDAG. In addition, E. faecalis CMs (but not E. faecium also contained: i phosphatidic acid; and ii two other unknown species of amino-containing PLs. Development of DAP resistance in both enterococcal species was associated with a significant decrease in CM fluidity and PG content, with a concomitant increase in GP-DGDAG. The strain-pairs did not differ in their outer CM translocation (flipping of amino-containing PLs. Fatty acid content did not change in the E. faecalis strain-pair, whereas a significant decrease in unsaturated fatty acids was observed in the DAP-resistant E. faecium isolate R446 (vs S447. Resistance to DAP in E. faecium was associated with distinct structural alterations of the cell envelope and cell wall thickening, as well as a decreased ability of DAP to depolarize and permeabilize the CM

Terapias somáticas para transtornos psiquiátricos resistentes ao tratamento Somatic therapies for treatment-resistant psychiatric disorders

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Raphael J Braga; Georgios Petrides

2007-01-01

OBJETIVO: O presente artigo é uma revisão do conhecimento atual relativo às terapias somáticas em psiquiatria, com foco em transtornos psiquiátricos resistentes ao tratamento usual. MÉTODO: Foi realizada uma pesquisa computadorizada da literatura no Medline utilizando as palavras "eletroconvulsoterapia", "estimulação magnética transcraniana", "terapia magnética convulsiva", "estimulação do nervo vago" e "estimulação cerebral profunda", com todos os termos traduzidos para o idioma inglês. Refe...

Investigação das atividades alelopática e antimicrobiana de Mikania laevigata (Asteraceae obtida de cultivos hidropônico e tradicional

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Leopoldo Baratto

Full Text Available Os extratos etanólicos de folhas de guaco (Mikania laevigata cultivado tradicionalmente no solo ou por hidroponia foram avaliados quanto às atividades alelopática e antimicrobiana. Para a atividade alelopática foi utilizado o ensaio de inibição da germinação de sementes de alface (Lactuca sativa, enquanto que para a atividade antimicrobiana utilizouse a técnica de difusão em disco. Observou-se um notável efeito alelopático dos extratos de ambos os cultivos, em especial do extrato etanólico do guaco tradicional, que mesmo na menor concentração testada inibiu completamente a germinação das sementes. Nenhum dos extratos etanólicos do guaco apresentou atividade antibacteriana significativa para as linhagens de Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis e Enterococcus faecium.

Detection of vancomycin resistances in enterococci within 3 1/2 hours

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Schröder, U. -Ch.; Beleites, C.; Assmann, C.; Glaser, U.; Hübner, U.; Pfister, W.; Fritzsche, W.; Popp, J.; Neugebauer, U.

2015-02-01

Vancomycin resistant enterococci (VRE) constitute a challenging problem in health care institutions worldwide. Novel methods to rapidly identify resistances are highly required to ensure an early start of tailored therapy and to prevent further spread of the bacteria. Here, a spectroscopy-based rapid test is presented that reveals resistances of enterococci towards vancomycin within 3.5 hours. Without any specific knowledge on the strain, VRE can be recognized with high accuracy in two different enterococci species. By means of dielectrophoresis, bacteria are directly captured from dilute suspensions, making sample preparation very easy. Raman spectroscopic analysis of the trapped bacteria over a time span of two hours in absence and presence of antibiotics reveals characteristic differences in the molecular response of sensitive as well as resistant Enterococcus faecalis and Enterococcus faecium. Furthermore, the spectroscopic fingerprints provide an indication on the mechanisms of induced resistance in VRE.

Enterococcus spp. Resistant to Multiple Antimicrobial Drugs and Determination of Fecal Contamination Levels in Mangrove Oysters (Crassostrea rhizophorae

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Cynthia Annes Rubião

2017-08-01

Full Text Available ABSTRACT The aim of this study was to determine and compare the Most Probable Number (MPN of Total Coliforms (TC, Escherichia coli and Enterococcus spp. and to characterize the antimicrobial resistance profiles of Enterococcus spp. isolated from oysters collected in the Barra de Guaratiba Mangrove, Rio de Janeiro, Brazil. The enumeration of E. coli has been used to indicate fecal contamination and hygienic-sanitary conditions of bivalve molluscs. Enterococci are capable to transfer several antimicrobial resistance genes to pathogenic bacteria, including those from Gram-negative group. The oysters were bought from local fishermen and a total of 123 individuals were analyzed. The TC, E. coli and Enterococcus spp. MPN mean were 26,300/100 g, 3,260/100 g and 2,820/100 g, respectively. The only correlation found was between TC and E. coli. Two strains of Enterococcus spp. were resistant to three different antimicrobial categories, including a high level resistance to streptomycin. One strain presented intermediate resistance to vancomycin. The E. coli levels exceeded the limits established by international legislation. This microbiological contamination in oysters reflects the water pollution and indicates a probable contamination of other seafood species from this mangrove, which can represent a risk for consumers and a threat to the environment and public health.

Structural studies of the Enterococcus faecalis SufU [Fe-S] cluster protein

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Frazzon Jeverson

2009-02-01

Full Text Available Abstract Background Iron-sulfur clusters are ubiquitous and evolutionarily ancient inorganic prosthetic groups, the biosynthesis of which depends on complex protein machineries. Three distinct assembly systems involved in the maturation of cellular Fe-S proteins have been determined, designated the NIF, ISC and SUF systems. Although well described in several organisms, these machineries are poorly understood in Gram-positive bacteria. Within the Firmicutes phylum, the Enterococcus spp. genus have recently assumed importance in clinical microbiology being considered as emerging pathogens for humans, wherein Enterococcus faecalis represents the major species associated with nosocomial infections. The aim of this study was to carry out a phylogenetic analysis in Enterococcus faecalis V583 and a structural and conformational characterisation of it SufU protein. Results BLAST searches of the Enterococcus genome revealed a series of genes with sequence similarity to the Escherichia coli SUF machinery of [Fe-S] cluster biosynthesis, namely sufB, sufC, sufD and SufS. In addition, the E. coli IscU ortholog SufU was found to be the scaffold protein of Enterococcus spp., containing all features considered essential for its biological activity, including conserved amino acid residues involved in substrate and/or co-factor binding (Cys50,76,138 and Asp52 and, phylogenetic analyses showed a close relationship with orthologues from other Gram-positive bacteria. Molecular dynamics for structural determinations and molecular modeling using E. faecalis SufU primary sequence protein over the PDB:1su0 crystallographic model from Streptococcus pyogenes were carried out with a subsequent 50 ns molecular dynamic trajectory. This presented a stable model, showing secondary structure modifications near the active site and conserved cysteine residues. Molecular modeling using Haemophilus influenzae IscU primary sequence over the PDB:1su0 crystal followed by a MD

Initial development and structure of biofilms on microbial fuel cell anodes

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Keller Jürg

2010-04-01

Full Text Available Abstract Background Microbial fuel cells (MFCs rely on electrochemically active bacteria to capture the chemical energy contained in organics and convert it to electrical energy. Bacteria develop biofilms on the MFC electrodes, allowing considerable conversion capacity and opportunities for extracellular electron transfer (EET. The present knowledge on EET is centred around two Gram-negative models, i.e. Shewanella and Geobacter species, as it is believed that Gram-positives cannot perform EET by themselves as the Gram-negatives can. To understand how bacteria form biofilms within MFCs and how their development, structure and viability affects electron transfer, we performed pure and co-culture experiments. Results Biofilm viability was maintained highest nearer the anode during closed circuit operation (current flowing, in contrast to when the anode was in open circuit (soluble electron acceptor where viability was highest on top of the biofilm, furthest from the anode. Closed circuit anode Pseudomonas aeruginosa biofilms were considerably thinner compared to the open circuit anode (30 ± 3 μm and 42 ± 3 μm respectively, which is likely due to the higher energetic gain of soluble electron acceptors used. The two Gram-positive bacteria used only provided a fraction of current produced by the Gram-negative organisms. Power output of co-cultures Gram-positive Enterococcus faecium and either Gram-negative organisms, increased by 30-70% relative to the single cultures. Over time the co-culture biofilms segregated, in particular, Pseudomonas aeruginosa creating towers piercing through a thin, uniform layer of Enterococcus faecium. P. aeruginosa and E. faecium together generated a current of 1.8 ± 0.4 mA while alone they produced 0.9 ± 0.01 and 0.2 ± 0.05 mA respectively. Conclusion We postulate that this segregation may be an essential difference in strategy for electron transfer and substrate capture between the Gram-negative and the Gram

Photocatalytic properties and selective antimicrobial activity of TiO2(Eu)/CuO nanocomposite

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Michal, Robert; Dworniczek, Ewa; Caplovicova, Maria; Monfort, Olivier; Lianos, Panagiotis; Caplovic, Lubomir; Plesch, Gustav

2016-05-01

TiO2(Eu)/CuO nanocomposites were prepared by precipitation method. The anatase nanocrystallites with a size of 26 nm exhibited well crystallized and characteristical dipyramidal morphology and {1 0 1} and {0 0 1} faceting. Transmission electron microscopy photographs with atomic resolution showed that the Eu(III) dopants were bounded on surface of titania. In the composites, the CuO nanocrystals exhibiting a monoclinic tenorite structure with a size in the range from 2 to 5 nm were grafted to the surface of titania. The influence of copper(II) oxide led to distinct selectivity in the photocatalytic and antimicrobial properties of the investigated TiO2(Eu)/CuO nanocomposites. While the presence of CuO nanocrystals strongly increased the photocatalytic production of hydrogen by ethanol reforming, it decreased the activity in photoinduced total mineralization of phenol comparing with non-modified TiO2(Eu). In investigated TiO2(Eu)/CuO powders, the photoinduced antimicrobial activity against membranes of Enterococcus species was influenced by the selective binding of CuO to the surface of the microorganism leading to distinct selectivity in their action. The activity against Enterococcus faecalis was higher than against Enterococcus faecium.

Enterococcus spp. Resistant to Multiple Antimicrobial Drugs and Determination of Fecal Contamination Levels in Mangrove Oysters (Crassostrea rhizophorae)

OpenAIRE

Rubião, Cynthia Annes; Franco, Robson Maia; Mesquita, Eliana de Fátima Marques de; Miguel, Marco Antonio Lemos; Cabral, Claudius Couto; Fonseca, Ana Beatriz Monteiro

2017-01-01

ABSTRACT The aim of this study was to determine and compare the Most Probable Number (MPN) of Total Coliforms (TC), Escherichia coli and Enterococcus spp. and to characterize the antimicrobial resistance profiles of Enterococcus spp. isolated from oysters collected in the Barra de Guaratiba Mangrove, Rio de Janeiro, Brazil. The enumeration of E. coli has been used to indicate fecal contamination and hygienic-sanitary conditions of bivalve molluscs. Enterococci are capable to transfer several ...

The Relationship among Tyrosine Decarboxylase and Agmatine Deiminase Pathways in Enterococcus faecalis

NARCIS (Netherlands)

Perez, Marta; Ladero, Victor; del Rio, Beatriz; Redruello, Begona; de Jong, Anne; Kuipers, Oscar; Kok, Jan; Martin, M. Cruz; Fernandez, Maria; Alvarez, Miguel A.

2017-01-01

Enterococci are considered mainly responsible for the undesirable accumulation of the biogenic amines tyramine and putrescine in cheeses. The biosynthesis of tyramine and putrescine has been described as a species trait in Enterococcus faecalis. Tyramine is formed by the decarboxylation of the amino

Prevalence and antibiotic-resistance characteristics of Enterococcus spp. Isolated from free-living and captive raptors in Central Illinois.

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Marrow, Judilee; Whittington, Julia K; Mitchell, Mark; Hoyer, Lois L; Maddox, Carol

2009-04-01

Due to their predatory nature, raptor species may serve as important indicators of environmental contamination with antimicrobial-resistant bacteria. Raptors prey on small rodents and birds that have diverse habitat ranges, including urban and rural environments, and their intestinal microflora can reflect that of the animals on which they feed. Enterococcus spp. were selected as target organisms because they have been isolated from the avian gastrointestinal tract, can be conferred by prey items, and because they are capable of multiple resistance patterns. They are also a concerning source of human antimicrobial resistance. In this study fecal cultures were obtained from 15 May 2004 to 31 August 2004, from 21 free-living raptors and four captive raptors. Enterococcus was isolated from 21 (84%) of the 25 birds, and 54 isolates were chosen for further study based upon unique colony morphology. The most common isolate recovered was Enterococcus faecalis (95%, 95% confidence interval [CI]: 89-100). One bird in the study was determined to have Enterococcus gallinarum. Two distinct ribotypes of E. faecalis were identified, one with unique bands at 11 and 13 kb and the other with unique bands at 14 and 20 kb. Both ribotypes were found in free-living and captive birds. The Enterococcus isolates in this study demonstrated a variety of antimicrobial-resistance characteristics, including almost complete resistance to amikacin, first-generation cephalosporins, spectinomycin, and sulphadimethoxime. Isolates demonstrated variable resistance to chloramphenicol, gentamicin, enrofloxacin, erythromycin, and ticarcillin. No phenotypically vancomycin-resistant E. faecalis isolates were recovered from any of the raptors; three isolates had intermediate level susceptibility. A significantly higher number of isolates collected from captive birds demonstrated resistance to chloramphenicol than those obtained from free-living birds. This trend was not duplicated with any of the remaining

Antibacterial Effect of All-in-one Self-etch Adhesives on Enterococcus faecalis

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Mohammad Esmaeel Ebrahimi Chaharom

2014-12-01

Full Text Available Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step self-etch adhesives on Enterococcus faecalis on days 1, 7 and 14 with the use of modified direct contact test. Materials and methods. The modified directcontact test was used to evaluate the antibacterial effect of Adper Easy One, Bond Force, Clearfil S3 Bond, Futurabond M, G-Bond, iBond and OptiBond All-in-one adhesives on Enterococcus faecalisafter aging the samples in phosphate-buffered saline for one, seven and fourteen days. Data were analyzed using one-way ANOVA and post hoc Tukey tests. Aging effect of each adhesive was evaluated by paired-sample test. In this study, P0.05. Conclusion. iBond exhibited the highest antibacterial effect on E. faecalis after one week. Futurabond and OptiBond All-in-one exhibited antibacterial effects against E. faecalis for one week.

Endocardite acuta da Staphylococcus haemolyticus meticillino sensibile, con recidiva dopo trattamento da ceppo meticillino resistente

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Giacomo Magnani

2005-03-01

Full Text Available Le endocarditi su valvole native (NVE da Stafilococchi coagulasi negativi (CoNS presentano un andamento aggressivo simile a quello da Staphylococcus aureus e sono difficili da trattare per l’alta incidenza da parte dei CoNS di resistenza a oxacillina.Viene riportato un caso di NVE da Staphylococcus haemolyticus meticillino sensibile, con risposta iniziale favorevole al trattamento con oxacillina, ma con successiva recidiva a distanza di tre mesi legata comparsa di ceppo oxacillino-resistente. L’ipotesi è che l’infezione sia stata sostenuta da una popolazione batterica con fenotipo eteroresistente, che in seguito al trattamento antibiotico ha sviluppato resistenza omogenea a oxacillina. Nell’impostare un trattamento per infezioni gravi da Stafilococchi sensibili in vitro ad oxacillina è necessario considerare sempre la presenza di un eteroresistenza.

Antibiotic Susceptibility Pattern of Gram-positive Cocci Cultured from Patients in Three University Hospitals in Tehran, Iran during 2001-2005

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Aligholi Marzieh

2009-10-01

Full Text Available Bacterial resistance to antibiotics is a serious problem and is increasing in prevalence world-wide at an alarming rate. The antimicrobial susceptibility patterns of 1897 gram-positive bacterial Isolates were evaluated. The minimum inhibitory concentration (MIC of isolates which comprised Staphylococcus aureus (927 isolates, coagulase-negative staphylococci (CNS; 425 isolates, Enterococcus faecalis (320 isolates, Enterococcus faecium (157 isolates, and pneumococci (50 isolates collected from 3 teaching hospitals in Tehran were determined by agar dilution method according to Clinical and Laboratory Standards Institute (CLSI guidelines. The presence of mecA gene was investigated in methicillin-resistant staphylococci by PCR method and vanA and vanB genes were targeted in enterococcal isolates by Multiplex PCR method. The resistance rate to methicillin among S. aureus and CNS isolates were 33% and 49%, respectively. All S. aureus isolates were susceptible to vancomycin .The lowest rate of resistance in all S. aureus isolates was found for rifampicin (<4%. The vancomycin resistance rate in enterococci isolates was 11% which was more frequent among E. faecium (19% than E. faecalis (4%, all resistant isolates carrying vanA. High-level resistance to gentamicin and streptomycin, were detected in 47% and 87% of enterococcal isolates respectively. The rate of penicillin resistance in pneumococci was 3% and about 27% of isolates had reduced susceptibility to penicillin. The prevalence of erythromycin resistant among pneumococci was 58%. All pneumococcal isolates were susceptible to ceftriaxone, rifampicin and vancomycin. Our data highlight the importance of access to updated bacterial susceptibility data regarding commonly prescribed agents for clinicians in Iran.

Survival of microorganisms representing the three Domains of life inside the International Space Station

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Francesco, Canganella; Giovanna, Bianconi

2007-09-01

The present work was mainly focused to study the response of representative non pathogenic microorganisms to the environment inside the space vehicle at different mission stages (10, 56, and 226 days) within the frame of the Italian ENEIDE mission, from Feb to Oct 2005. Microorganisms were chosen according to their phylogenetic position and cell structures; they were representatives of the three taxonomic domains and belonged to different ecosystems (food, soil, intestinal tract, plants, deep-sea). They were the followings: Thermococcus guaymasensis (Domain Archaea); Saccharomyces cerevisiae (Domain Eucarya); Escherichia coli, Bacillus subtilis, Lactobacillus acidophilus, Enterococcus faecium, Pseudomonas fluorescens, and Rhizobium tropici (Domain Bacteria). As main environmental parameters we were interested in: a) space radiations; b) microgravity; c) temperature. The response of microorganisms was investigated in terms of survival rates, cell structure modifications, and genomic damages. The survival of cells was affected by both radiation doses and intrinsec cell features. As expected, only samples kept on the ISS for 226 days showed significant levels of mortality. Asfar as regard the effect on cell structures, these samples showed also remarkable morphological changes, particularly for Escherichia coli, Enterococcus faecium, and Saccharomyces cerevisiae. The data collected allowed to get new insights into the biological traits of microorganisms exposed to space environment during the flight on a spacecraft. Moreover, the result obtained may be important for the improvement of human conditions aboard space vehicles (nutraceuticals for astronauts and disinfections of ISS modules) and also for the potential development of closed systems devoted to vegetable productions and organic recycling.

Characterization of transferable tetracycline resistance genes in Enterococcus faecalis isolated from raw food

DEFF Research Database (Denmark)

Wilcks, Andrea; Andersen, Sigrid Rita; Licht, Tine Rask

2005-01-01

The prevalence of tetracycline resistance, and of specific genetic determinants for this resistance was investigated in 1003 strains of Enterococcus faecalis isolated from various raw food products originating from five categories including chicken meat, other poultry meat, beef, pork, and 'other...

Characterization of two N-acetyl muramoylhydrolases of Streptococcus faecium ATCC 9790

International Nuclear Information System (INIS)

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 [ 14 C]penicillin G and been tentatively identified as penicillin binding proteins 1 and 5, respectively

Prevalencia de Staphylococcus aureus resistente a meticilina en infecciones de piel y partes blandas en pacientes ambulatorios

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Verónica Bermejo

2012-08-01

Full Text Available Recientemente se ha observado un aumento en la prevalencia de Staphylococcus aureus resistente a la meticilina (SAMR en pacientes ambulatorios con infecciones de piel y partes blandas (IPyPB. Los datos epidemiológicos locales disponibles son limitados. Se realizó un estudio descriptivo, prospectivo, de consultantes con IPyPB en la División Infectología del Hospital General de Agudos Juan A. Fernández, en el período 01/10/2009 a 31/01/2011. Fueron 130; edad mediana 36 años (RIC 25.9-43.5; hombres 61.5%. El 46.9% era HIV+. Cien cultivos (76.9%, de 100 pacientes, resultaron positivos: 83 S. aureus, 8 Streptococcus spp. y 9 con otros microorganismos. De los S. aureus aislados, 62 (74.7% fueron resistentes a oxacilina, 12 (14.4% a clindamicina, 14 (16.9% a eritromicina, 5 (6% a ciprofloxacina, presentando en algunos casos más de una resistencia. Todos fueron sensibles a rifampicina y minociclina, y 98.8% (82 a trimetoprima-sulfametoxazol. El 83.8% (52 de los pacientes con SAMR tenían algún factor de riesgo (FR, sin diferencias con los pacientes con otros aislamientos. La presentación clínica más frecuente de IPyPB / SAMR fue forunculosis: 56.4 (35/62 vs. 28.9% (11/38 en infecciones por otros microorganismos (p = 0.013. La resistencia a oxacilina fue similar entre pacientes HIV+ y negativos (79.1 vs. 70%, p = 0.179 (34/43 vs. 28/40. Concluimos que en la población estudiada se encontró una alta prevalencia de SAMR, independientemente de la serología para HIV o la presencia de FR. Las opciones de tratamiento empírico para este microorganismo son minociclina y trimetoprima-sulfametoxazol.

Microbiological characteristics of "androlla", a Spanish traditional pork sausage.

Science.gov (United States)

García Fontán, María C; Lorenzo, José M; Parada, Ana; Franco, Inmaculada; Carballo, Javier

2007-02-01

identified as Enterococcus faecium, one as Enterococcus faecalis and 101 as Enterococcus inter faecalis-faecium.

In vitro antimicrobial activity of pistachio (Pistacia vera L.) polyphenols.

Science.gov (United States)

Bisignano, Carlo; Filocamo, Angela; Faulks, Richard M; Mandalari, Giuseppina

2013-04-01

We investigated the antimicrobial properties of polyphenol-rich fractions derived from raw shelled and roasted salted pistachios. American Type Culture Collection (ATCC), food and clinical isolates, of Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Pseudomonas mirabilis), Gram-positive bacteria (Listeria monocytogenes, Enterococcus hirae, Enterococcus faecium, Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus), the yeasts Candida albicans and Candida parapsilosis and the fungus Aspergillus niger were used. Pistachio extracts were active against Gram-positive bacteria with a bactericidal effect observed against L. monocytogenes (ATCC strains and food isolates), S. aureus and MRSA clinical isolates. Extracts from raw shelled pistachios were more active than those from roasted salted pistachios. The bactericidal activity of pistachio extracts could be used to help control the growth of some microorganisms in foods to improve safety and may find application as a topical treatment for S. aureus. © 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

PCR-based identification of selected pathogens associated with endodontic infections in deciduous and permanent teeth.

Science.gov (United States)

Cogulu, Dilsah; Uzel, Atac; Oncag, Ozant; Eronat, Cemal

2008-09-01

The aim of the present study was to evaluate the presence of the selected pathogens in samples from deciduous and permanent tooth root canals by using PCR method and to determine the association of these organisms with clinical symptoms. A total of 145 children, 5 to 13 years old, were involved in this study. The presence of selected pathogens (Actinomyces israelii, Candida albicans, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Streptococcus intermedius, Treponema denticola, Parvimonas micra, Tannerella forsythensis, Enterococcus faecium, Prevotella melaninogenica) in infected root canals was studied using PCR. T. denticola (P = .012, .02) and E. faecalis (P = .012, .04) were highly associated with periapical radiolucency and previous pain, while P. gingivalis was associated with tenderness to percussion in both deciduous and permanent teeth (P = .01, .015). The results of the present study confirm that certain species of microorganisms are associated with clinical signs and symptoms of endodontic disease in both deciduous and permanent teeth.

Efektivitas antibakteri ekstrak daun sirih (Piper betle Linn)terhadap bakteri Enterococcus faecalis (Antibacterial effectiveness of betel leaf extract (Piper Betle Linn) to Enterococcus faecalis)

OpenAIRE

Armianty Armianty; Indrya Kirana Mattulada

2014-01-01

Enterococcus faecalis is one of bacteria which have resistance against the pulp tissue defense mechanism and often found in endodontic infections. This bacterial is may hold good colonization, can survive in the root canal without other bacteria, and is capable of producing toxins directly or through the induction of inflammation. Betel leaf (Piper betle Linn)contain essential oils, as the main components of the essential oils are phenols and compounds, among other derivate such a...

Nuevos genotipos de arroz resistentes a la Piriculariosis obtenidos por cultivo de anteras

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Rodolfo I Castro

2012-01-01

Full Text Available Título en inglés: New blast resistant rice genotypes obtained by and anthers culture. Resumen: En la Estación Experimental del Arroz Los Palacios, perteneciente al Instituto Nacional de Ciencias Agrícolas de Cuba (INCA, se efectuaron cruzamientos entre cuatro cultivares resistentes a la Piriculariosis y seis de buen comportamiento agronómico y las anteras de las plantas F2 fueron cultivadas in vitro para evaluar la formación de callos en tres medios líquidos: N6-1, N6-m y NL, así como la regeneración de plantas verdes y albinas, en el medio MS. Las dos primeras generaciones de las nuevas líneas obtenidas fueron evaluadas para caracteres agronómicos y la segunda generación, además, para resistencia frente a la  Piriculariosis. Las líneas que combinaron resistencia a la Piriculariosis y buenos caracteres agronómicos fueron evaluadas en condiciones de infección natural, con alta presión del patógeno. La utilización de la técnica del cultivo de anteras mostró alta dependencia del genotipo y el medio de cultivo. Con el medio NL se lograron los valores más altos para la formación de callos. Se obtuvieron nuevos genotipos resistentes a la Piriculariosis y  de alto rendimiento agrícola. Palabras clave: Arroz; Mejoramiento genético; Cultivo in Vitro de anteras Summary: Crosses were made between four blast resistant and six rice varieties of good agronomic performance, at the Los Palacios Rice Research Station of the National Agricultural Sciences Institute of Cuba (INCA and the anthers from F2 plants were in vitro culture using three liquid media: N6-1, N6m, and NL, for callus formation and after plants regenerations using MS medium. The first two generations of breeding lines were evaluated for agronomic characters and the second generations, also, for Blast resistant. The lines that combined resistance to Blast and good agronomic performance were evaluated under high pressure of natural Blast infection conditions. The success

Estudo teórico-experimental da contribuição da armadura para a capacidade resistente de vigas parcialmente revestidas

OpenAIRE

Leandro de Amorim Cavalcanti

2010-01-01

Este trabalho tem por objetivo investigar a contribuição da armadura para a capacidade resistente de vigas mistas parcialmente revestidas, bem como sua eficiência para promover o comportamento conjunto aço-concreto, imprescindível para a obtenção de vigas mistas. O estudo engloba uma investigação experimental com ensaios de vigas sob flexão em quatro pontos e uma simulação numérica utilizando o pacote computacional DIANA®, visando obter dados do comportamento de vigas mistas parcialmente reve...

\\"Avaliação da desinfecção da dentina radicular em profundidade provocada pela irradiação do laser de diodo de alta potência\\"

OpenAIRE

Eliana Barbosa de Souza

2007-01-01

A presença de microrganismos no interior do sistema de canais radiculares é a principal causa do fracasso na terapia endodôntica. A importância da sanificação durante o preparo do canal fica clara, portanto. Dentre os microrganismos isolados nos casos de insucesso o Enterococcus faecalis é comumente encontrado. O E. faecalis é um microrganismo resistente à terapia endodôntica, à medicação intracanal de hidróxido de cálcio e sua presença contribui para o insucesso em Endodontia. A radiação las...

Comparing Temperature Effects on E. Coli, Salmonella, and Enterococcus Survival in Surface Waters

Science.gov (United States)

The objective of this study was to compare dependency of survival rates on temperature for indicator organisms E. coli and Enterococcus and the pathogen Salmonella in surface waters. A database of 86 survival datasets from peer-reviewed papers on inactivation of E. coli, Salmonel...

Human Salivary Protein Histatin 5 Has Potent Bactericidal Activity against ESKAPE Pathogens.

Science.gov (United States)

Du, Han; Puri, Sumant; McCall, Andrew; Norris, Hannah L; Russo, Thomas; Edgerton, Mira

2017-01-01

ESKAPE ( Enterococcus faecium , Staphylococcus aureus , Klebsiella pneumoniae , Acinetobacter baumanni , Pseudomonas aeruginosa , and Enterobacter species) pathogens have characteristic multiple-drug resistance and cause an increasing number of nosocomial infections worldwide. Peptide-based therapeutics to treat ESKAPE infections might be an alternative to conventional antibiotics. Histatin 5 (Hst 5) is a salivary cationic histidine-rich peptide produced only in humans and higher primates. It has high antifungal activity against Candida albicans through an energy-dependent, non-lytic process; but its bactericidal effects are less known. We found Hst 5 has bactericidal activity against S. aureus (60-70% killing) and A. baumannii (85-90% killing) in 10 and 100 mM sodium phosphate buffer (NaPB), while killing of >99% of P. aeruginosa , 60-80% E. cloacae and 20-60% of E. faecium was found in 10 mM NaPB. Hst 5 killed 60% of biofilm cells of P. aeruginosa , but had reduced activity against biofilms of S. aureus and A. baumannii . Hst 5 killed 20% of K. pneumonia biofilm cells but not planktonic cells. Binding and uptake studies using FITC-labeled Hst 5 showed E. faecium and E. cloacae killing required Hst 5 internalization and was energy dependent, while bactericidal activity was rapid against P. aeruginosa and A. baumannii suggesting membrane disruption. Hst 5-mediated killing of S. aureus was both non-lytic and energy independent. Additionally, we found that spermidine conjugated Hst 5 (Hst5-Spd) had improved killing activity against E. faecium, E. cloacae , and A. baumannii . Hst 5 or its derivative has antibacterial activity against five out of six ESKAPE pathogens and may be an alternative treatment for these infections.

Tratamiento con estatinas en pacientes pediátricos con síndrome nefrótico resistente a esteroides. Reporte de dos casos

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C Sánchez-García

2017-01-01

Full Text Available El síndrome nefrótico se define por la asociación de proteinuria, hipoalbuminemia, hiperlipidemia y edema. El 80% de los pacientes pediátricos con síndrome nefrótico primario responde a la terapia con esteroides; el 20% restante requiere asociar otros medicamentos para alcanzar la remisión (ciclofosfamida, ciclosporina. La hiperlipidemia en el síndrome nefrótico es debida tanto a un incremento en la síntesis acompañada de disminución en la eliminación de los lípidos de la sangre; siendo la causa directa de esto la proteinuria. La hiperlipidemia incrementa el riesgo cardiovascular, así como el daño glomerular. Con base en esto, la hiperlipidemia persistente en el síndrome nefrótico resistente a esteroides debe ser tratada. Los inhibidores de la 3-hidroxi-3-metilglutaril-coenzima A (HMG-CoA reductasa han demostrado efecto antiinflamatorio, inmunomodulador y antiproliferativo. Por ello el papel de las estatinas en el síndrome nefrótico va más allá de su efecto hipolipemiante. Presentamos dos casos de pacientes pediátricos con diagnóstico de síndrome nefrótico resistente a esteroides y su evolución durante el tratamiento con ciclosporina y estatinas.

Bioprosthetic Aortic Valve Endocarditis in Association with Enterococcus durans.

Science.gov (United States)

Fallavollita, Luca; Di Gioacchino, Lorena; Balestrini, Fabrizio

2016-04-01

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.

In vitro activity of flomoxef and cefazolin in combination with vancomycin.

Science.gov (United States)

Simon, C; Simon, M

1991-01-01

207 clinical isolates from strains of patients from the University Children's Hospital of Kiel were investigated for their in vitro activity with the agar dilution method against flomoxef and cefazolin (alone and partially in combination with vancomycin). Staphylococci were also tested with other cephalosporins (cefoxitin, cefamandole, cefotaxime, cefotetan and latamoxef). Flomoxef and cefazolin always acted more vigorously on staphylococci than the other cephalosporins. Resistance of Staphylococcus aureus strains against flomoxef and cefazolin did not occur but was found in 15 and 5 of 98 Staphylococcus epidermidis strains, respectively. Enterococcus faecalis strains were always resistant against both drugs; Streptococcus faecium strains were only moderately sensitive. Combined testing of flomoxef or cefazolin with vancomycin showed synergism in almost all staphylococcal strains. Synergism was stronger when S. epidermidis strains were only weakly sensitive to or resistant against flomoxef and cefazolin in comparison to highly sensitive strains. Flomoxef (or cefazolin) acted synergistically in combination with vancomycin on E. faecalis and S. faecium with the exception of two strains of E. faecalis which showed an additive effect of both drugs.

Antibiotic resistance monitoring: the Spanish programme. The VAV Network. Red de Vigilancia de Resistencias Antibióticas en Bacterias de Origen Veterinario.

Science.gov (United States)

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

2000-05-01

Antimicrobial resistance is a problem in modern public health and antimicrobial use and especially misuse, the most important selecting force for bacterial antibiotic resistance. As this resistance must be monitored we have designed the Spanish network 'Red de Vigilancia de Resistencias Antibióticas en Bacterias de Origen Veterinario'. This network covers the three critical points of veterinary responsibility, bacteria from sick animals, bacteria from healthy animals and bacteria from food animals. Key bacteria, antimicrobials and animal species have been defined for each of these groups along with laboratory methods for testing antimicrobial susceptibility and for data analysis and reporting. Surveillance of sick animals was first implemented using Escherichia coli as the sentinel bacterium. Surveillance of E. coli and Enterococcus faecium from healthy pigs was implemented in 1998. In July 1999, data collection on Salmonella spp. was initiated in poultry slaughterhouses. Additionally, the prevalence of vancomycin resistant E. faecium was also monitored. This network has specific topics of interest related to methods of determining resistance, analysis and reporting of data, methods of use for veterinary practitioners and collaboration with public health authorities.

Primer aislamiento en Argentina de Staphylococcus aureus resistente a la meticilina adquirido en la comunidad con sensibilidad intermedia a la vancomicina y no sensibilidad a la daptomicina

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Laura Errecalde

Full Text Available Describimos el primer caso en Argentina de Staphylococcus aureus resistente a la meticilina adquirido en la comunidad con sensibilidad intermedia a la vancomicina y no sensibilidad a la daptomicina. Caso clínico: Paciente masculino, con antecedente de insuficiencia renal crónica en hemodiálisis y osteosíntesis de cadera debido a una fractura. Se internó por síndrome febril persistente luego del desplazamiento de la prótesis por un traumatismo. Se aisló de hemocultivos S. aureus resistente a la meticilina adquirido en la comunidad. Durante el tratamiento con vancomicina y daptomicina, se observó un aumento gradual de la CIM de vancomicina de 1 µg/ml (VSSA a 2 µg/ml (h-VISA y a 4 µg/ml (VISA, y la emergencia de no sensibilidad a daptomicina (CIM = 4 µg/ml. Al suspender la vancomicina y la daptomicina, la cepa revirtió al fenotipo de sensibilidad a ambas drogas. Es mandatorio evaluar por CIM la sensibilidad a vancomicina y a daptomicina intratratamiento cuando estas drogas se usan como terapia.

Haemonchus resistente a lactona macrocíclica em caprinos naturalmente parasitados

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Mattos Mary Jane Tweedie de

2004-01-01

Full Text Available O ivermectin, antiparasitário amplamente utilizado em caprinos jovens, foi avaliado sobre nematódeos gastrintestinais, em todas as fases parasitárias. Doze caprinos jovens, naturalmente parasitados foram utilizados no experimento, sendo um grupo de seis animais medicado com ivermectin, na dose de 200µg.kg-1 v.o. e o outro grupo utilizado como controle. Para a avaliação, utilizou-se o teste de redução na contagem de ovos (FECR, redução de larvas infectantes e carga parasitária. Amostras fecais de caprinos foram coletadas no dia da medicação (dia zero, aos sete e catorze dias. No décimo quarto dia pós-medicação, todos os caprinos foram sacrificados, para a coleta de helmintos e cálculo da carga parasitária total. A redução do número de ovos (FECR e a eficácia sobre adultos foi de 42,10 % e 32,62 %, respectivamente.O gênero Haemonchus representou 100 % da população do grupo medicado e 99,58 % do grupo controle. Estes resultados indicam que os caprinos já estavam parasitados por Haemonchus resistente ao ivermectin.

Photocatalytic properties and selective antimicrobial activity of TiO2(Eu)/CuO nanocomposite

International Nuclear Information System (INIS)

Michal, Robert; Dworniczek, Ewa; Caplovicova, Maria; Monfort, Olivier; Lianos, Panagiotis; Caplovic, Lubomir; Plesch, Gustav

2016-01-01

Highlights: • Nanocomposites composed of Eu-doped anatase grafted with CuO. • Increase in photocatalytic hydrogen production due to CuO acting as electrons sink. • CuO in composites decreasing the photoinduced total mineralization of phenol. • Selective photoinduced antimicrobial activity against Enterococcus species. - Abstract: TiO 2 (Eu)/CuO nanocomposites were prepared by precipitation method. The anatase nanocrystallites with a size of 26 nm exhibited well crystallized and characteristical dipyramidal morphology and {1 0 1} and {0 0 1} faceting. Transmission electron microscopy photographs with atomic resolution showed that the Eu(III) dopants were bounded on surface of titania. In the composites, the CuO nanocrystals exhibiting a monoclinic tenorite structure with a size in the range from 2 to 5 nm were grafted to the surface of titania. The influence of copper(II) oxide led to distinct selectivity in the photocatalytic and antimicrobial properties of the investigated TiO 2 (Eu)/CuO nanocomposites. While the presence of CuO nanocrystals strongly increased the photocatalytic production of hydrogen by ethanol reforming, it decreased the activity in photoinduced total mineralization of phenol comparing with non-modified TiO 2 (Eu). In investigated TiO 2 (Eu)/CuO powders, the photoinduced antimicrobial activity against membranes of Enterococcus species was influenced by the selective binding of CuO to the surface of the microorganism leading to distinct selectivity in their action. The activity against Enterococcus faecalis was higher than against Enterococcus faecium.

Draft Genome Sequence of the Tyramine Producer Enterococcus durans Strain IPLA 655

Science.gov (United States)

Ladero, Victor; Linares, Daniel M.; del Rio, Beatriz; Fernandez, Maria; Martin, M. Cruz

2013-01-01

We here report a 3.059-Mbp draft assembly for the genome of Enterococcus durans strain IPLA 655. This dairy isolate provides a model for studying the regulation of the biosynthesis of tyramine (a toxic compound). These results should aid our understanding of tyramine production and allow tyramine accumulation in food to be reduced. PMID:23682153

Potencial de cruzamento natural entre o arroz transgênico resistente ao herbicida glufosinato de amônio e o arroz daninho

OpenAIRE

Noldin,J.A.; Yokoyama,S.; Antunes,P.; Luzzardi,R.

2002-01-01

A utilização de cultivares de arroz irrigado resistentes a herbicidas não-seletivos, como o glufosinato de amônio, pode se constituir numa alternativa de controle de arroz daninho em lavouras de arroz irrigado. O objetivo deste trabalho foi avaliar a taxa e o sentido do cruzamento natural entre plantas de uma linhagem modificada geneticamente para resistência ao herbicida glufosinato de amônio (arroz GM) e ao arroz daninho. A taxa de cruzamento natural entre o arroz GM como receptor feminino ...

Confirmation of putative stormwater impact on water quality at a Florida beach by microbial source tracking methods and structure of indicator organism populations.

Science.gov (United States)

Brownell, M J; Harwood, V J; Kurz, R C; McQuaig, S M; Lukasik, J; Scott, T M

2007-08-01

The effect of a stormwater conveyance system on indicator bacteria levels at a Florida beach was assessed using microbial source tracking methods, and by investigating indicator bacteria population structure in water and sediments. During a rain event, regulatory standards for both fecal coliforms and Enterococcus spp. were exceeded, contrasting with significantly lower levels under dry conditions. Indicator bacteria levels were high in sediments under all conditions. The involvement of human sewage in the contamination was investigated using polymerase chain reaction (PCR) assays for the esp gene of Enterococcus faecium and for the conserved T antigen of human polyomaviruses, all of which were negative. BOX-PCR subtyping of Escherichia coli and Enterococcus showed higher population diversity during the rain event; and higher population similarity during dry conditions, suggesting that without fresh inputs, only a subset of the population survives the selective pressure of the secondary habitat. These data indicate that high indicator bacteria levels were attributable to a stormwater system that acted as a reservoir and conduit, flushing high levels of indicator bacteria to the beach during a rain event. Such environmental reservoirs of indicator bacteria further complicate the already questionable relationship between indicator organisms and human pathogens, and call for a better understanding of the ecology, fate and persistence of indicator bacteria.

Antibacterial activity of plant extracts and phytochemicals on antibiotic-resistant bacteria Atividade de extratos vegetais e fitofármacos sobre bactérias resistentes a antibióticos

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Gislene G. F. Nascimento

2000-10-01

Full Text Available The antimicrobial activity of plant extracts and phytochemicals was evaluated with antibiotic susceptible and resistant microorganisms. In addition, the possible synergistic effects when associated with antibiotics were studied. Extracts from the following plants were utilized: Achillea millifolium (yarrow, Caryophyllus aromaticus (clove, Melissa offficinalis (lemon-balm, Ocimun basilucum (basil, Psidium guajava (guava, Punica granatum (pomegranate, Rosmarinus officinalis (rosemary, Salvia officinalis (sage, Syzygyum joabolanum (jambolan and Thymus vulgaris (thyme. The phytochemicals benzoic acid, cinnamic acid, eugenol and farnesol were also utilized. The highest antimicrobial potentials were observed for the extracts of Caryophyllus aromaticus and Syzygyum joabolanum, which inhibited 64.2 and 57.1% of the tested microorganisms, respectively, with higher activity against antibiotic-resistant bacteria (83.3%. Sage and yarrow extracts did not present any antimicrobial activity. Association of antibiotics and plant extracts showed synergistic antibacterial activity against antibiotic-resistant bacteria. The results obtained with Pseudomonas aeruginosa was particularly interesting, since it was inhibited by clove, jambolan, pomegranate and thyme extracts. This inhibition was observed with the individual extracts and when they were used in lower concentrations with ineffective antibiotics.Foi avaliada a atividade antimicrobiana de extratos vegetais e fitofármacos frente a microrganismos sensíveis e resistentes a antibióticos, bem como observado o possível efeito sinérgico da associação entre antibióticos e extratos vegetais. Foram utilizados os extratos de plantas cujo nomes populares são: tomilho, alecrim, cravo-da-Índia, jambolão, erva cidreira, romã, goiaba, sálvia, manjericão e mil-folhas, e ainda os fitofármacos, ácido benzóico, ácido cinâmico, eugenol e farnesol. Na avaliação da atividade antimicrobiana através do m

An Investigation of the Prevalence of Antibiotic Resistance in Enterococcus Species Isolated from Delivery Room of University Hospital of Qom City, 2015, Iran

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Faezeh Kabiri

2016-06-01

Full Text Available Background and Objectives: Enterococci are Gram-positive cocci that are found in abundance in the environment. The ability of these bacteria for long-term survival in hospital environment, increases the chance of patients for infections caused by this bacterium. Therefore, identification of possible sources and reservoirs is helpful in identifying the potential sources in sudden outbreaks. The current study was conducted to determine the prevalence rate and antibiotic resistance pattern in environmental Enterococcus isolates collected from delivery room environment of Alzahra and Izadi university hospitals in Qom. Methods: In this descriptive cross-sectional study, over a period of 3 month, sampling was performed using swabbing method from delivery rooms of alzahra and izadi hospitals in Qom, and were examined for the presence of Enterococci. After isolation, Enterococcus species were examined using different biochemical tests, and the antibiotic resistance pattern in the environmental was assessed according to disk-diffusion test according to Clinical and Laboratory Standards Institute (CLSI standards. The data were described by frequency tables. Results: In this study, out of 216 obtained isolates, 7(3.2% belonged to Enterococcus genus. 4(57% out of 7 Enterococcus strains isolated from surfaces of delivery room, had multiple resistances based on antibiotic sensitivity test using antiobiogram test. Conclusion: According to increasing growth of nosocomial infection caused by resistant strains of Enterococcus spp. and their spread in hospital environment, use of infection control measures are necessary to eliminate the potential sources and prevent the infection.  

Herbicidas alternativos para controle de biótipos de Conyza bonariensis e C. canadensis resistentes ao glyphosate Alternative herbicides to control glyphosate-resistant biotypes of Conyza bonariensis and C. canadensis

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M.S. Moreira

2010-01-01

Full Text Available Após sucessivos anos, aplicações do herbicida glyphosate em pomares de citros no Estado de São Paulo selecionaram biótipos resistentes de Conyza bonariensis e C. canadensis. Na ocorrência de plantas daninhas resistentes em uma área agrícola, tornam-se necessárias mudanças nas práticas de manejo para obtenção de adequado controle das populações resistentes, bem como para a redução da pressão de seleção sobre outras espécies. Assim, este trabalho foi realizado com o objetivo de identificar herbicidas alternativos para controle de biótipos de Conyza spp. resistentes ao herbicida glyphosate, com aplicações em diferentes estádios fenológicos da planta daninha. Três experimentos foram conduzidos em campo, em pomares de citros em formação, sobre plantas de buva em estádio fenológico de dez folhas e no pré-florescimento. Para plantas no estádio de dez folhas, controle satisfatório foi obtido com aplicações de glyphosate + bromacil + diuron (1.440 + 1.200 + 1.200 g ha-1, glyphosate + atrazina (1.440 + 1.500 g ha-1 e glyphosate + diuron (1.440 + 1.500 g ha-1. Quando em estádio de pré-florescimento de Conyza spp., a aplicação do herbicida amônio-glufosinato, na dose de 400 g ha-1, isolado ou associado a MSMA, bromacil+diuron, metsulfuron, carfentrazone e paraquat, foi a alternativa viável para controle dos biótipos resistentes ao glyphosate.After successive years, glyphosate applications on São Paulo-Brazil citrus orchards selected resistant biotypes of Conyza bonariensis and C. canadensis. The occurrence of herbicide-resistant weed biotypes at some agricultural area makes it necessary to change the management practices to reach effective control of the selected resistant populations, as well as to reduce selection pressure on the other species. Thus, this work aimed to identify the alternative herbicides to control glyphosate-resistant biotypes of Conyza spp., with applications at different weed phenological

Knockdown resistance in pyrethroid-resistant horn fly (Diptera: Muscidae populations in Brazil Resistência Knockdown em populações de mosca-dos-chifres do Brasil resistentes aos piretróides

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Gustavo A. Sabatini

2009-09-01

Full Text Available To investigate the kdr (knockdown resistance resistance-associated gene mutation and determine its frequency in pyrethroid-resistant horn fly (Haematobia irritans populations, a total of 1,804 horn flies of 37 different populations from all Brazilian regions (North, Northeast, Central-West, Southeast, and South were molecular screened through polymerase chain reaction (PCR. The kdr gene was not detected in 87.08% of the flies. However, the gene was amplified in 12.92% of the flies, of which 11.70% were resistant heterozygous and 1.22% were resistant homozygous. Deviation from Hardy-Weinberg equilibrium (HWE was found only in 1 ranch with an excess of heterozygous. When populations were grouped by region, three metapopulations showed significant deviations of HWE (Central-West population, South population and Southeast population. This indicates that populations are isolated one from another and kdr occurrence seems to be an independent effect probably reflecting the insecticide strategy used by each ranch. Although resistance to pyrethroids is disseminated throughout Brazil, only 48% of resistant populations had kdr flies, and the frequency of kdr individuals in each of these resistant populations was quite low. But this study shows that, with the apparent exception of the Northeast region, the kdr mechanism associated with pyrethroid resistance occurs all over Brazil.Com o objetivo de verificar a ocorrência e determinar a frequência da mutação kdr (knock down resistance em populações de Haematobia irritans (mosca-dos-chifres resistentes aos piretróides, foram analisados 1.804 indivíduos de 37 populações de todas as Regiões do Brasil. Com exceção da Região Nordeste, o kdr (knock down resistance gene foi encontrado em populações de todas as regiões. A mutação não foi detectada em 87,08% dos indivíduos. Entretanto, o gene foi amplificado de 12,92% das moscas, das quais 11,70% se mostraram heterozigotas resistentes e 1

Enterococcus faecalis proteolytic activity: The mechanism of resistance to antimicrobial peptides

Czech Academy of Sciences Publication Activity Database

Nešuta, Ondřej; Monincová, Lenka; Buděšínský, Miloš; Hexnerová, Rozálie; Hadravová, Romana; Čeřovský, Václav

2017-01-01

Roč. 15, č. 1 (2017), s. 24-25 ISSN 2336-7202. [Mezioborové setkání mladých biologů, biochemiků a chemiků /17./. 30.05.2017-01.06.2017, Milovy] R&D Projects: GA TA ČR(CZ) TA04010638; GA MZd(CZ) NV16-27726A Institutional support: RVO:61388963 Keywords : antimicrobial peptides * bacterial resistance * Enterococcus faecalis Subject RIV: EE - Microbiology, Virology

Antimicrobial susceptibility changes in Enterococcus faecalis following various penicillin exposure regimens.

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Hodges, T L; Zighelboim-Daum, S; Eliopoulos, G M; Wennersten, C; Moellering, R C

1992-01-01

Penicillin-"virgin" strains of Enterococcus faecalis collected from a population of individuals with no previous antibiotic exposure were subjected in vitro to penicillin delivered as repeated pulses, stepwise increasing concentrations, or sustained levels of a single concentration. Changes in resistance to penicillin were assessed by determination of MICs, and time-kill studies were performed to evaluate changes in tolerance to the bactericidal effects of penicillin. Isogenic clones, derived...

In vitro study of beneficial properties and safety of lactic acid bacteria isolated from Portuguese fermented meat products.

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Todorov, S D; Franco, B D G M; Wiid, I J

2014-09-01

Many lactic acid bacteria produce bacteriocins with a rather broad spectrum of inhibition, which could offer potential applications in food preservation. Bacteriocin production by starter cultures may bring advantage to these strains in competitive interactions with pathogenic bacteria from the food matrix. The objective of this study was to determine the safety of beneficial strains (Lactobacillus plantarum ST202Ch and ST216Ch, Enterococcus faecium ST211Ch, and Lactobacillus sakei ST22Ch, ST153Ch and ST154Ch) previously isolated from fermented meat products and characterised as bacteriocin producers. Auto-aggregation was strain-specific, and values of 28.97, 27.86 and 28.56% were recorded for L. sakei ST22Ch, ST153Ch and ST154Ch, respectively, 16.95 and 14.58% for L. plantarum ST202Ch and ST216Ch, respectively, and 12.77% for E. faecium ST211Ch. Various degrees of co-aggregation between 28.85 and 44.76% for Listeria monocytogenes 211 and 409, and between 23.60 to 34.96% for E. faecium ATCC 19443 were observed. According to the results of the diffusion method, the studied strains demonstrated susceptibility to penicillin G, ampicillin, amoxicillin, amoxicillin/clavulonic acid, imipenem, linezolid, and tetracycline. In addition, the susceptibility of the six strains to various non-antibiotic commercial drugs was examined. Production of β-galactosidase by L. sakei ST22Ch, ST153Ch and ST154Ch, L. plantarum ST202Ch and ST216Ch, and E. faecium ST211Ch was confirmed by employing sterile filter paper discs impregnated with o-nitrophenyl-β-D-galactopyranose. A statistically significant (P<0.001) inhibition of Mycobacterium tuberculosis growth by bacteriocins produced by L. plantarum ST202Ch (38.3%) and ST216Ch (48.6%), L. sakei ST153Ch (16.2%) and ST154Ch (16.1%), and E. faecium ST211Ch (21.7%) was observed. As determined by the polymerase chain reaction, the tested strains showed a low virulence gene profile.

Characterization of Enterococcus species isolated from marine recreational waters by MALDI-TOF MS and Rapid ID API® 20 Strep system.

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Christ, Ana Paula Guarnieri; Ramos, Solange Rodrigues; Cayô, Rodrigo; Gales, Ana Cristina; Hachich, Elayse Maria; Sato, Maria Inês Zanoli

2017-05-15

MALDI-TOF Mass Spectrometry Biotyping has proven to be a reliable method for identifying bacteria at the species level based on the analysis of the ribosomal proteins mass fingerprint. We evaluate the usefulness of this method to identify Enterococcus species isolated from marine recreational water at Brazilian beaches. A total of 127 Enterococcus spp. isolates were identified to species level by bioMérieux's API® 20 Strep and MALDI-TOF systems. The biochemical test identified 117/127 isolates (92%), whereas MALDI identified 100% of the isolates, with an agreement of 63% between the methods. The 16S rRNA gene sequencing of isolates with discrepant results showed that MALDI-TOF and API® correctly identified 74% and 11% of these isolates, respectively. This discrepancy probably relies on the bias of the API® has to identify clinical isolates. MALDI-TOF proved to be a feasible approach for identifying Enterococcus from environmental matrices increasing the rapidness and accuracy of results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Antimicrobial Activity of Chitosan Film Forming Solution Enriched with Essential Oils; an in Vitro Assay.

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Raphaël, Kana Jean; Meimandipour, Amir

2017-01-01

Background: The resistance of the bacteria and fungi to the innumerous antimicrobial agents is a major challenge in the treatment of the infections demands to the necessity for searching and finding new sources of substances with antimicrobial properties. The incorporation of the essential oils (EOs) in chitosan film forming solution may enhance antimicrobial properties. However, its use as the feeding additive in the poultry nutrition needs to clarify the product's activity against both pathogen and the useful microbes in the gastrointestinal tract. Objectives: In the present study, we carried out an in vitro investigation and evaluated the antimicrobial activity of chitosan film forming solution incorporated with essential oils (CFs+EOs) against microbial strains including Staphylococcus aureus, Escherichia coli, Enterococcus faecium, Lactobacillus rahmnosus, Aspergillus niger and Alternaria alternate . Material and Methods: In three replicates, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of different treatments including: 1- essential oils (EOs), 2- chitosan film solution (CFs), and 3-chitosan film solution enriched with EOs (CFs+EOs) were determined against above mentioned microbes. Results: The results indicated that the chitosan solution enriched with essential oils (CFs+EOs) is capable of inhibiting the bacterial and fungal growth even at the lowest concentrations. The MIC and MBC for all the antimicrobial agents against Escherichia coli and Staphylococcus aureus were very low compared to the concentrations needed to inhibit the growth of useful bacteria, Lactobacillus rahmnosu and Enterococcus faecium . The antifungal activity of chitosan was enhanced as the concentration of EOs increased in the film solution. Conclusion: Chitosan-EOs complexes are the promising candidate for novel contact antimicrobial agents that can be used in animal feeds.

Comparative study of the in vitro activity of a new fluoroquinolone, ABT-492.

Science.gov (United States)

Harnett, S J; Fraise, A P; Andrews, J M; Jevons, G; Brenwald, N P; Wise, R

2004-05-01

The in vitro activity of a new fluoroquinolone, ABT-492, was determined. MICs were compared with those of two beta-lactams, telithromycin, ciprofloxacin and four later generation fluoroquinolones. The effects of human serum and of inoculum concentration were also investigated. MIC data indicate that ABT-492 has potent activity against Gram-positive organisms with enhanced anti-staphylococcal activity compared with earlier fluoroquinolones, in addition to activity against beta-haemolytic streptococci, pneumococci including penicillin- and fluoroquinolone-resistant strains and vancomycin-susceptible and -resistant Enterococcus faecalis but not Enterococcus faecium. ABT-492 was the most active agent tested against Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitidis, fluoroquinolone-susceptible Neisseria gonorrhoeae and anaerobes. Good activity was observed for ABT-492 amongst the Enterobacteriaceae and anaerobes tested, but ciprofloxacin showed superior activity for species of Proteus, Morganella and Providencia, as well as for Pseudomonas spp. In common with the other fluoroquinolones tested, organisms with reduced susceptibility to ciprofloxacin had raised MIC(90)s to ABT-492. The one isolate of H. influenzae tested with reduced fluoroquinolone susceptibility had an ABT-492 MIC close to that of the population lacking a mechanism of quinolone resistance. ABT-492 was more active than ciprofloxacin against Chlamydia spp. An inoculum effect was observed with a number of isolates of Staphylococcus aureus, Streptococcus pneumoniae, E. faecium, Klebsiella spp. and Escherichia coli, in addition to moderately raised MICs in the presence of 70% serum protein. The clinical significance of these findings is yet to be determined. ABT-492 is a new fluoroquinolone with excellent activity against both Gram-positive and Gram-negative organisms, with many potential clinical uses.

Competition effects with mixed stands of wheat and kochia (Kochia scoparia biotypes resistant and susceptible to acetolactase synthase inhibitor herbicides Efeitos competitivos da mistura de stands de trigo e biotipos de kochia (Kochia scoparia resistentes e susceptíveis aos herbicidas inibidores da acetolactase sintase

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P.J. Christoffoleti

1994-08-01

Full Text Available Greenhouse experiments were conducted to compare the competitive ability of sulfonylurea resistant and susceptible kochia (Kochia scoparia L. Schard compared to wheat. The results of several replacement series experiments indicate that wheat was the dominant competitor, and an average of one wheat plant reduced resistant kochia yield per plant equal to the effect of 4.8 resistant kochia or 5.4 susceptible kochia plants. Intraspeciflc competition was more important than interspecific competition for wheat, whereas the reverse was true for the resistant and susceptible kochia. The results of the niche differentiation index (NDI indicate that wheat and either resistant or susceptible kochia are only partly limited by the same resources. The resistant and susceptible kochia, however, are limited by the same resources.Experimentos foram instalados em condições de casa-de-vegetação com o objetivo de comparar a capacidade competitiva de biotipos resistentes e suscetíveis aos herbicidas inibidores da enzima acetolactase synthase da planta daninha kochia (Kochia scoparia L. Schard comparada com trigo. Os resultados de diversos experimentos, utilizando a metodologia chamada de substitutiva, indicaram que o trigo foi o competidor dominante, e em média uma planta de trigo reduziu o crescimento da planta de kochia resistente igual ao efeito de 4,8 plantas de kochia resistente ou 5,4 plantas de kochia suscetível. A competição chamada de intraespecífíca foi mais importante que a competição interespecífica para o trigo, porém o inverso foi verdadeiro para os biotípos resistentes e susceptíveis de kochia. Os resultados do índice de diferenciação ecológica indicaram que trigo e qualquer um dos dois biotípos de kochia estudados foram limitados apenas parcialmente pelos mesmos recursos de crescimento. No entanto, o crescimento dos biotípos resistentes e susceptíveis de kochia foram limitados pelos mesmos fatores de crescimento.

Crescimento diferencial de biótipos de Conyza SPP. resistente e suscetível ao herbicida glifosato Differential growth of glyphosate-resistant and susceptible biotypes of Conyza SPP

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