title: Cloning, sequencing, and transcriptional analysis of the dnaK heat shock operon of Listeria monocytogenes.
abstract: The complete dnaK operon of Listeria monocytogenes was isolated by chromosome walking using the previously cloned dnaK gene as a probe. Molecular analysis of the locus identified 6 genes in the order hrcA, grpE, dnaK, dnaJ, orf35, and orf29. Primer extension analysis revealed 3 transcription start sites-S1, S2, and S3-upstream of the hrcA, grpE, and dnaJ, respectively. The transcription from S1 was heat inducible. Analysis of the sequences revealed the consensus promoter sequences of gram-positive bacteria, P1 and P2 upstream of the hrcA and dnaJ, respectively. The hrcA gene and a regulatory sequence, designated CIRCE (controlling inverted repeat of chaperone expression), play a role in the regulation of expression of the dnaK locus in response to heat shock in several gram-positive bacteria. Their presence upstream of the dnaK locus in L. monocytogenes suggested a similar regulatory mechanism for the transcription initiated at the promoter, P1. Northern blot analysis led to the detection of 4 mRNA species of 4.9 kb, 3.6 kb, 3.6 kb, and 1.2 kb; the first 2 species were heat inducible. The current results indicate that 4 distinct transcripts directed by 3 promoters are involved in the expression of the dnaK operon of L. monocytogenes.
authors.affiliation: Department of Microbiology, Kyorin University School of Medicine, Mitaka, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hanawa
authors.forename: M
authors.initials: M
authors.lastname: Kai
authors.forename: S
authors.initials: S
authors.lastname: Kamiya
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006360:Heat-Shock Proteins / Q000235:genetics; D006358:Hot Temperature; D008089:Listeria monocytogenes / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009876:Operon; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins / Q000235:genetics; D017421:Sequence Analysis; D013045:Species Specificity; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; C068113:GrpE protein, Bacteria; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; C406264:orf29 protein, Listeria monocytogenes; C104236:orf35 protein, Bacillus subtilis; C063842:dnaK protein, E coli