title: clpB, a class III heat-shock gene regulated by CtsR, is involved in thermotolerance and virulence of Enterococcus faecalis.
abstract: Here, we transcriptionally and phenotypically characterized the clpB gene from Enterococcus faecalis. Northern blot analysis identified a monocistronic mRNA strongly induced at 48 and 50 °C. In silico analysis identified that the clpB gene encodes a protein of 868 aa with a predicted molecular mass of approximately 98 kDa, presenting two conserved ATP-binding domains. Sequence analysis also identified a CtsR-binding box upstream of the putative -10 sequence, and inactivation of the ctsR gene resulted in an approximately 2-log increase in clpB mRNA expression, confirming ClpB as a member of the CtsR regulon. While expression of clpB was induced by heat stress, a ΔclpB strain grew relatively well under many different stressful conditions, including elevated temperatures. However, expression of ClpB appears to play a major role in induced thermotolerance and in pathogenesis, as assessed by using the Galleria mellonella virulence model.
authors.affiliation: Center for Oral Biology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.|Instituto de Microbiologia Paulo de Góes, Bloco I, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, 21491-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Naira Elane Moreira
authors.initials: NEM
authors.lastname: de Oliveira
authors.affiliation: Center for Oral Biology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
authors.forename: Jaqueline
authors.initials: J
authors.lastname: Abranches
authors.affiliation: Center for Oral Biology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
authors.forename: Anthony O
authors.initials: AO
authors.lastname: Gaca
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Bloco I, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, 21491-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Marinella Silva
authors.initials: MS
authors.lastname: Laport
authors.affiliation: Instituto de Biofísica Carlos Chagas Filho, Bloco G, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, 21491-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Clarissa R
authors.initials: CR
authors.lastname: Damaso
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Bloco I, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, 21491-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Maria do Carmo de Freire
authors.initials: MDCF
authors.lastname: Bastos
authors.affiliation: Center for Oral Biology, Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA.
authors.forename: José A
authors.initials: JA
authors.lastname: Lemos
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Bloco I, Universidade Federal do Rio de Janeiro, CCS, Cidade Universitária, 21491-902, Rio de Janeiro, RJ, Brazil.
authors.forename: Marcia
authors.initials: M
authors.lastname: Giambiagi-deMarval
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D004195:Disease Models, Animal; D013293:Enterococcus faecalis / Q000187:drug effects / Q000472:pathogenicity* / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response; D006358:Hot Temperature; D006801:Humans; D008969:Molecular Sequence Data; D009036:Moths / Q000382:microbiology*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; C118338:CtsR protein, bacteria; D006360:Heat-Shock Proteins; D012097:Repressor Proteins