Search

Your search keyword '"Pierrick Meignen"' showing total 4 results
Start Over Author "Pierrick Meignen"
4 results on '"Pierrick Meignen"'

1. Nationwide molecular epidemiology of methicillin-resistant Staphylococcus aureus responsible for horse infections in France

Author

François Guérin, Marguerite Fines-Guyon, Pierrick Meignen, Géraldine Delente, Caroline Fondrinier, Nancy Bourdon, Vincent Cattoir, and Albertine Léon

Subjects
MRSA, Equine infections, ST398, ST8, Microbiology, QR1-502
Abstract

Abstract Background The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) isolated in horse infections is not well documented, especially in France. The aim of the study was to evaluate the prevalence of MRSA isolates in horse infections from 2007 to 2013 in France and to characterize phenotypically and genotypically this collection. Results Out of 1393 S. aureus horse isolates, 85 (6.1%) were confirmed to be MRSA. Interestingly, the prevalence of MRSA significantly increased from 2007–2009 to 2010–2013 (0.7 vs. 9.5%, P

Published
2017
Full Text
View/download PDF

2. Unexpected Cell Wall Alteration-Mediated Bactericidal Activity of the Antifungal Caspofungin against Vancomycin-Resistant Enterococcus faecium

Author

Fanny Joalland, Vincent Cattoir, Jean-Christophe Giard, Michel Auzou, Didier Goux, Pierrick Meignen, Felipe Cava, Sara B. Hernández, David Enot, Christophe Isnard, François Gravey, François Guérin, Unité de Recherche Risques Microbiens (U2RM), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN), Groupe de Recherche sur l'Adaptation Microbienne (GRAM 2.0), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Umeå University, Centre de Microscopie Appliquée à la Biologie [Caen] (CMABio3), Interactions Cellules Organismes Environnement (ICORE), Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-CHU Caen, Institut Gustave Roussy (IGR), Métabolisme, cancer et immunité = Metabolism, Cancer & Immunity [CRC] (Equipe labellisée Ligue contre le cancer), Centre de Recherche des Cordeliers (CRC (UMR_S_1138 / U1138)), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université de Paris (UP)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université de Paris (UP), CHU Pontchaillou [Rennes], ARN régulateurs bactériens et médecine (BRM), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN), École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université Paris Cité (UPCité)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université Paris Cité (UPCité), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Jonchère, Laurent, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Université Paris Cité (UPCité)-École pratique des hautes études (EPHE)

Subjects
E. faecium, Antifungal Agents, VRE, medicine.drug_class, [SDV]Life Sciences [q-bio], Antibiotics, Enterococcus faecium, Microbial Sensitivity Tests, Biology, Bacterial cell structure, Microbiology, Vancomycin-Resistant Enterococci, echinocandins, 03 medical and health sciences, chemistry.chemical_compound, Antibiotic resistance, Caspofungin, Cell Wall, Vancomycin, Intensive care, medicine, Humans, Pharmacology (medical), [SDV.MP] Life Sciences [q-bio]/Microbiology and Parasitology, Mechanisms of Action: Physiological Effects, Gram-Positive Bacterial Infections, 030304 developmental biology, Pharmacology, 0303 health sciences, 030306 microbiology, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, bacterial infections and mycoses, 3. Good health, Anti-Bacterial Agents, [SDV] Life Sciences [q-bio], antibacterial, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Infectious Diseases, Cell wall organization, chemistry, Peptidoglycan
Abstract

International audience; Enterococcus faecium has become a major opportunistic pathogen with the emergence of vancomycin-resistant enterococci (VRE). As part of the gut microbiota, they have to cope with numerous stresses including effects of antibiotics and other xenobiotics, especially in patients hospitalized in intensive care units (ICUs) who receive many medications. The aim of this study was to investigate the impact of the most prescribed xenobiotics for ICU patients on fitness, pathogenicity and antimicrobial resistance of the vanB-positive E. faecium Aus0004 reference strain. Several phenotypic analyses were carried out and we observed that caspofungin, an antifungal agent belonging to the echinocandins family, had an important effect on E. faecium growth in vitro. We confirmed this effect by electron microscopy and peptidoglycan analysis and showed that, even at a subinhibitory concentration (¼ × MIC, 8 mg/L), caspofungin had an impact on cell wall organization especially in abundance of some muropeptide precursors. By RNA-seq, it was also shown that around 20% of the transcriptome were altered in the presence of caspofungin with 321 and 259 significantly upregulated and downregulated genes, respectively. Since the fungal target of caspofungin (i.e., beta-(1,3)-glucan synthase) was absent in bacteria, the mechanistic pathway of caspofungin activity was investigated. The repression of genes involved in the pyruvate metabolism seemed to have a drastic impact on bacterial cell viability while decrease of glycerol metabolism could explain the conformational modifications of peptidoglycan. This is the first report of caspofungin antibacterial activity against E. faecium, highlighting the potential impact of non-antibiotic xenobiotics against bacterial pathogens.

Published
2020
Full Text
View/download PDF

3. Subinhibitory Concentrations of Ciprofloxacin Enhance Antimicrobial Resistance and Pathogenicity of Enterococcus faecium

Author

Jean Christophe Giard, Clara Sinel, Margherita Cacaci, François Guérin, Maurizio Sanguinetti, Vincent Cattoir, Pierrick Meignen, and Bryan William Davies

Subjects
0301 basic medicine, Bacilli, medicine.drug_class, 030106 microbiology, Antibiotics, Enterococcus faecium, Microbial Sensitivity Tests, Quinolones, Settore MED/07 - MICROBIOLOGIA E MICROBIOLOGIA CLINICA, Microbiology, 03 medical and health sciences, Antibiotic resistance, Bacterial Proteins, Ciprofloxacin, Drug Resistance, Bacterial, medicine, Humans, Pharmacology (medical), Adhesins, Bacterial, Gene, Mechanisms of Action: Physiological Effects, Gram-Positive Bacterial Infections, Pharmacology, biology, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, Fold change, Anti-Bacterial Agents, Bacterial adhesin, 030104 developmental biology, Infectious Diseases, Collagen, Transcriptome, Genome, Bacterial, medicine.drug
Abstract

Enterococcus faecium has emerged as a major opportunistic pathogen for 2 decades with the spread of hospital-adapted multidrug-resistant clones. As members of the intestinal microbiota, they are subjected to numerous bacterial stresses, including antibiotics at subinhibitory concentrations (SICs). Since fluoroquinolones are extensively prescribed, SICs are very likely to occur in vivo , with potential effects on bacterial metabolism with subsequent modulation of opportunistic traits. The aim of this study was to evaluate globally the impact of SICs of ciprofloxacin on antimicrobial resistance and pathogenicity of E. faecium . Transcriptomic analysis was performed by RNA sequencing (RNA-seq) (HiSeq 2500; Illumina) using the vanB -positive reference strain E. faecium Aus0004 in the absence or presence of ciprofloxacin SIC (0.38 mg/liter, i.e., 1/8 of the MIC). Several genetic and phenotypic tests were used for validation. In the presence of ciprofloxacin SIC, 196 genes were significantly induced, whereas 286 genes were significantly repressed, meaning that 16.8% of the E. faecium genome was altered. Among upregulated genes, EFAU004_02294 (fold change, 14.3) encoded a protein (Qnr of E. faecium [EfmQnr]) homologue of Qnr proteins involved in quinolone resistance in Gram-negative bacilli. Its implication in intrinsic and adaptive fluoroquinolone (FQ) resistance in E. faecium was experimentally ascertained. Moreover, EFAU004_02292, coding for the collagen adhesin Acm, was also induced by the SIC of ciprofloxacin (fold change, 8.2), and higher adhesion capabilities were demonstrated phenotypically. Both EfmQnr and Acm determinants may play an important role in the transition from a commensal to a pathogenic state of E. faecium that resides in the gut of patients receiving fluoroquinolone therapy.

Published
2017

Catalog

Books, media, physical & digital resources
See catalog results