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Michael S Gilmore - One of the best experts on this subject based on the ideXlab platform.
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pathogenicity of Enterococci
Microbiology spectrum, 2019Co-Authors: Michael S Gilmore, Elizabeth Fiore, Daria Van TyneAbstract:Enterococci are unusually well adapted for survival and persistence in a variety of adverse environments, including on inanimate surfaces in the hospital environment and at sites of infection. This intrinsic ruggedness undoubtedly played a role in providing opportunities for Enterococci to interact with other overtly drug-resistant microbes and acquire additional resistances on mobile elements. The rapid rise of antimicrobial resistance among hospital-adapted Enterococci has rendered hospital-acquired infections a leading therapeutic challenge. With about a quarter of a genome of additional DNA conveyed by mobile elements, there are undoubtedly many more properties that have been acquired that help Enterococci persist and spread in the hospital setting and cause diseases that have yet to be defined. Much remains to be learned about these ancient and rugged microbes, particularly in the area of pathogenic mechanisms involved with human diseases.
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Gram‐Positive Pathogens - Pathogenicity of Enterococci.
Microbiology spectrum, 2019Co-Authors: Elizabeth Fiore, Daria Van Tyne, Michael S GilmoreAbstract:Enterococci are unusually well adapted for survival and persistence in a variety of adverse environments, including on inanimate surfaces in the hospital environment and at sites of infection. This intrinsic ruggedness undoubtedly played a role in providing opportunities for Enterococci to interact with other overtly drug-resistant microbes and acquire additional resistances on mobile elements. The rapid rise of antimicrobial resistance among hospital-adapted Enterococci has rendered hospital-acquired infections a leading therapeutic challenge. With about a quarter of a genome of additional DNA conveyed by mobile elements, there are undoubtedly many more properties that have been acquired that help Enterococci persist and spread in the hospital setting and cause diseases that have yet to be defined. Much remains to be learned about these ancient and rugged microbes, particularly in the area of pathogenic mechanisms involved with human diseases.
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tracing the Enterococci from paleozoic origins to the hospital
Cell, 2017Co-Authors: Michael S Gilmore, Francois Lebreton, Abigail L Manson, Jose T Saavedra, Timothy J Straub, Ashlee M EarlAbstract:We examined the evolutionary history of leading multidrug resistant hospital pathogens, the Enterococci, to their origin hundreds of millions of years ago. Our goal was to understand why, among the vast diversity of gut flora, Enterococci are so well adapted to the modern hospital environment. Molecular clock estimation, together with analysis of their environmental distribution, phenotypic diversity, and concordance with host fossil records, place the origins of the Enterococci around the time of animal terrestrialization, 425–500 mya. Speciation appears to parallel the diversification of hosts, including the rapid emergence of new enterococcal species following the End Permian Extinction. Major drivers of speciation include changing carbohydrate availability in the host gut. Life on land would have selected for the precise traits that now allow pathogenic Enterococci to survive desiccation, starvation, and disinfection in the modern hospital, foreordaining their emergence as leading hospital pathogens.
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the Enterococci pathogenesis molecular biology and antibiotic resistance
2002Co-Authors: Michael S Gilmore, Don B ClewellAbstract:Table of Contents 1. History, Taxonomy, Biochemical Characteristics, and Antibiotic Susceptibility Testing of Enterococci, Richard R. Facklam, Maria da Gloria S. Carvalho, and Lucia M. Teixeira 2. Nonhuman Reservoirs of Enterococci, Frank M. Aarestrup, Patrick Butaye, and Wolfgang Witte 3. Enterococci as Members of the Intestinal Microflora of Humans, Gerald W. Tannock and Greg Cook 4. Physiology of Enterococci, Mark M. Huycke 5. Enterococcal Cell Wall, Jacques Coyette and Lynne E. Hancock 6. Plasmids and Transposons, Keith E. Weaver, Louis B. Rice, and Gordon Churchward 7. Conjugation and Genetic Exchange in Enterococci, Don B. Clewell and Gary M. Dunny 8. Enterococcal Virulence, Michael S. Gilmore, Phillip S. Coburn, Sreedhar R. Nallapareddy, and Barbara E. Murray 9. Acquired Antibiotic Resistances in Enterococci, Vivek Kak and Joseph W. Chow 10. Enterococcal Disease: Epidemiology and Treatment, Preeti N. Malani, Carol A. Kauffman, and Marcus J. Zervos 11. The Genome of Enterococcus faecalis V583: a Tool for Discovery, W. Michael McShan and Nathan Shankar
M.arie-paule Caprais - One of the best experts on this subject based on the ideXlab platform.
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Microbial and chemical markers: runoff transfer in animal manure-amended soils
Journal of Environmental Quality, 2011Co-Authors: Anne Jaffrézic, Emilie Jardé, Michèle Gourmelon, M.arie-paule Caprais, A.m. Pourcher, D. Heddadj, P. Cottinet, M. Bilal, M. Derrien, R. MartiAbstract:Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.
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Microbial and chemical markers: runoff transfer in animal manure-amended soils
Journal of Environmental Quality, 2011Co-Authors: Anne Jaffrézic, Emilie Jardé, Michèle Gourmelon, M.arie-paule CapraisAbstract:Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms Escherichia coli and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (E. coli, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and Lactobacillus amylovorus), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.
Henrik Westh - One of the best experts on this subject based on the ideXlab platform.
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Update on prevalence and mechanisms of resistance to linezolid, tigecycline and daptomycin in Enterococci in Europe Towards a common nomenclature
Drug Resistance Updates, 2018Co-Authors: Jennifer K Bender, Anette M Hammerum, Henrik Westh, Vincent Cattoir, Kristin Hegstad, Ewa Sadowy, Teresa M Coque, Kirsten Schaffer, Karen Burns, Stephen MurchanAbstract:Vancomycin-resistant Enterococci (VRE) are important nosocomial pathogens. Invasive VRE infections are difficult to treat since common therapeutic options including ampicillin and glycopeptides often fail. In vitro, most VRE remain susceptible to last-resort antibiotics such as linezolid, tigecycline and daptomycin. However, neither tigecycline nor linezolid act in a bactericidal manner, and daptomycin has proven activity only at high dosages licensed for treating enterococcal endocarditis. Despite these pharmacological and therapeutic limitations, reports on resistance to these last-resort drugs in VRE, and Enterococci in general, have increased in recent years. In this review, we briefly recapitulate the current knowledge on the mode of action as well as the known and novel mechanisms of resistance and describe surveillance data on resistance to linezolid, tigecycline and daptomycin in Enterococci. In addition, we also suggest a common nomenclature for designating Enterococci and VRE with resistances to these important last-resort antibiotics.
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Vancomycin-resistant Enterococci at a large university hospital in Denmark.
APMIS : acta pathologica microbiologica et immunologica Scandinavica, 1996Co-Authors: Anne Kjerulf, Lars V. Pallesen, Henrik WesthAbstract:Enterococci are part of the normal human fecal flora and also part of the fecal flora of many animals. Vancomycin- and ampicillin-resistant Enterococci give rise to infections that may virtually be untreatable with antibiotics. Antibiotic use in humans is a risk factor for development or selection of vancomycin-resistant Enterococci. In animals the related glycopeptide avoparcin is used, especially in poultry, as a food additive to promote growth. Selective pressures for vancomycin-resistant Enterococci are high in Denmark with the production of 105 million poultry and the use of 24,000 kg avoparcin per year. The possible impact on vancomycin resistance among human isolates of Enterococci remains to be defined. Furthermore, there has been a 3-fold increase in vancomycin usage during the last 5 years at our hospital, from 2.4 to 7 kg/year. We examined 91 stool specimens from 67 patients in risk units at our hospital. Using a selective medium (KAA agar), 17 strains of Enterococcus faecium grew on the selective medium and 3 (18%) were vancomycin-resistant (MIC > 256 mg/l). Using PCR and an internal probe, vanA was found in the vancomycin-resistant Enterococci. No association between vancomycin therapy and carriage of VRE was demonstrated in these patients.
Anne Jaffrézic - One of the best experts on this subject based on the ideXlab platform.
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Microbial and chemical markers: runoff transfer in animal manure-amended soils
Journal of Environmental Quality, 2011Co-Authors: Anne Jaffrézic, Emilie Jardé, Michèle Gourmelon, M.arie-paule Caprais, A.m. Pourcher, D. Heddadj, P. Cottinet, M. Bilal, M. Derrien, R. MartiAbstract:Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.
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Microbial and chemical markers: runoff transfer in animal manure-amended soils
Journal of Environmental Quality, 2011Co-Authors: Anne Jaffrézic, Emilie Jardé, Michèle Gourmelon, M.arie-paule CapraisAbstract:Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms Escherichia coli and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (E. coli, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and Lactobacillus amylovorus), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.
Helena Stack - One of the best experts on this subject based on the ideXlab platform.
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Development of a rapid, one-step screening method for the isolation of presumptive proteolytic Enterococci.
Journal of microbiological methods, 2016Co-Authors: Ken Graham, Rosemary Rea, P.j. Simpson, Helena StackAbstract:Abstract Enterococci show higher proteolytic activities than other lactic acid bacteria and thus have received considerable attention in scientific literature in recent years. Proteolytic enzymes of Enterococci have warranted the use of some species as starter, adjuncts or protective cultures and as probiotics, while in some strains they have also been linked with virulence. Consequently, the isolation and identification of proteolytic Enterococci is becoming of increasing interest and importance. However, current screening methods for proteolytic Enterococci can be time consuming, requiring a two-step procedure which may take up to 96 h. This study describes a method, utilising Kanamycin Skim Milk Aesculin Azide (KSMEA) agar, for the isolation of proteolytic Enterococci in one-step, thereby significantly reducing screening time. KSMEA combines the selective properties of Kanamycin Aesculin Azide Agar (KAA) with skim milk powder for the detection of proteolytic Enterococci. Enterococci produced colonies with a black halo on KSMEA which were accompanied by a zone of clearing in the media when Enterococci were proteolytic. KSMEA medium retained the selectivity of KAA, while proteolytic Enterococci were easily distinguished from non-proteolytic Enterococci when two known strains were propagated on KSMEA. KSMEA also proved effective at isolating and detecting Enterococci in raw milk, faeces and soil. Isolates recovered from the screen were confirmed as Enterococci using genus-specific primers. Proteolytic Enterococci were present in the raw milk sample only and were easily distinguishable from non-proteolytic Enterococci and other microorganisms. Therefore, KSMEA provides a rapid, one-step screening method for the isolation of presumptive proteolytic Enterococci.