title: Organization of heat shock dnaK and groE operons of the nosocomial pathogen Enterococcus faecium.
abstract: Enterococcus faecium is a frequently antibiotic-resistant opportunistic pathogen that is commonly recovered from hospitalized patients. The genetic organization of the dnaK operon was analyzed and was shown to consist of at least four heat shock genes, hrcA-grpE-dnaK-dnaJ. The dnaK/J intergenic region was 140 bp shorter than in E. faecalis. The dnaK operon was expressed from a putative sigma(A)-type promoter (PhrcA) upstream of the hrcA start codon and was preceded by two conserved CIRCE sequences. Northern hybridization revealed the presence of multiple mRNAs in the dnaK operon. Conversely, the groE operon was transcribed as a single mRNA. Induction of dnaK and groEL genes occurred in response to either heat shock or exposure to other stress agents.
authors.affiliation: Instituto de Microbiologia Prof. Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21491-590, Brazil.
authors.forename: Marinella S
authors.initials: MS
authors.lastname: Laport
authors.forename: Leonardo Lima
authors.initials: LL
authors.lastname: Dos Santos
authors.forename: José A C
authors.initials: JA
authors.lastname: Lemos
authors.forename: Maria
authors.initials: M
authors.lastname: do Carmo F Bastos
authors.forename: Robert A
authors.initials: RA
authors.lastname: Burne
authors.forename: Marcia
authors.initials: M
authors.lastname: Giambiagi-Demarval
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D018834:Chaperonin 60 / Q000235:genetics; D021901:DNA, Intergenic; D013293:Enterococcus faecalis / Q000235:genetics; D016984:Enterococcus faecium / Q000235:genetics*; D005786:Gene Expression Regulation; D015964:Gene Expression Regulation, Bacterial; D023061:Gene Order; D050956:HSP40 Heat-Shock Proteins / Q000235:genetics; D006360:Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D018832:Molecular Chaperones / Q000235:genetics*; D008969:Molecular Sequence Data; D009876:Operon / Q000235:genetics*; D009997:Osmotic Pressure; D018384:Oxidative Stress; D011401:Promoter Regions, Genetic; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D001426:Bacterial Proteins; D018834:Chaperonin 60; D021901:DNA, Intergenic; C068113:GrpE protein, Bacteria; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D012329:RNA, Bacterial; D012333:RNA, Messenger