title: Contribution of a PerR-like regulator to the oxidative-stress response and virulence of Enterococcus faecalis.
abstract: PerR is one of the most important transcriptional regulators involved in the oxidative-stress response in Bacillus subtilis. Here, the homologous gene in Enterococcus faecalis, ranked among the leading causes of nosocomial infection, was characterized and analysed. Phenotype analysis showed that the perR mutant was significantly more resistant to H2O2 challenge (P < 0.05). Expression of eight genes with potential roles in the oxidative-stress response was determined in the wild-type and perR-mutant strains by real-time quantitative PCR. Surprisingly, low quantitative differences in the transcriptional activity of these genes in the mutant versus wild-type were observed. Likewise, this locus was not involved in survival within murine macrophages, but in the mouse peritonitis model, the perR mutant appeared less lethal than the JH2-2 wild-type strain. The combined results show that PerR affects E. faecalis virulence and that its implication in the transcriptional regulation in this bacterium deviates from the B. subtilis model.
authors.affiliation: Laboratoire de Microbiologie de l'Environnement, EA 956 soutenue par l'INRA, IRBA, Université de Caen, 14032 Caen Cedex, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Verneuil
authors.affiliation: Laboratoire de Microbiologie de l'Environnement, EA 956 soutenue par l'INRA, IRBA, Université de Caen, 14032 Caen Cedex, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Rincé
authors.affiliation: Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, 00168, Rome, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Sanguinetti
authors.affiliation: Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, 00168, Rome, Italy.
authors.forename: Brunella
authors.initials: B
authors.lastname: Posteraro
authors.affiliation: Institute of Microbiology, Catholic University of Sacred Heart, L. go F. Vito 1, 00168, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Fadda
authors.affiliation: Laboratoire de Microbiologie de l'Environnement, EA 956 soutenue par l'INRA, IRBA, Université de Caen, 14032 Caen Cedex, France.
authors.forename: Yanick
authors.initials: Y
authors.lastname: Auffray
authors.affiliation: Laboratoire de Microbiologie de l'Environnement, EA 956 soutenue par l'INRA, IRBA, Université de Caen, 14032 Caen Cedex, France.
authors.forename: Axel
authors.initials: A
authors.lastname: Hartke
authors.affiliation: Laboratoire de Microbiologie de l'Environnement, EA 956 soutenue par l'INRA, IRBA, Université de Caen, 14032 Caen Cedex, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Giard
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D013293:Enterococcus faecalis / Q000472:pathogenicity* / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D018384:Oxidative Stress / Q000502:physiology*; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C122138:peroxide repressor proteins