title: Cloning, characterization, and possible origin of the Prevotella loescheii dnaK homolog.
abstract: Heat shock proteins play an important role in bacterial survival and response to environmental stress. We cloned the Prevotella loescheii HSP70 homolog (dnaK) and characterized the coding sequence, regulatory regions, and evolutionary relationships to other bacteria. Predicted proteins encoded by the P. loescheii dnaK homolog (open reading frame ORF-1) and two downstream coding regions, ORF-2 and ORF-3, are highly homologous to the proteins encoded by ORF-4 (dnaK), ORF-5, and ORF-6 from the dnaK region of Porphyromonas gingivalis. The dnaK promoter resembles other HSP (heat shock protein) promoters. Alignment of the predicted protein encoded by ORF-2 showed significant homology to the Bacteroides fragilis tnpA gene from the transposon Tn4555, whereas the ORF-3 protein showed homology to B. fragilis transposase (Tn5220) and integrase (Tn4555) proteins. This suggests a transposition-like event may be responsible for transfer of these genes between Porphyromonas and Prevotella.
authors.affiliation: Truman Medical Center, Department of Pathology, University of Missouri School of Medicine, 3201 Holmes, Kansas City, Missouri 64108, USA. citronj@umkc.edu
authors.forename: J N
authors.initials: JN
authors.lastname: Manch-Citron
authors.forename: P J
authors.initials: PJ
authors.lastname: Shahani
authors.forename: R
authors.initials: R
authors.lastname: Schneider
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D029968:Escherichia coli Proteins; D019143:Evolution, Molecular; D005798:Genes, Bacterial; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D016966:Porphyromonas gingivalis / Q000235:genetics; D018720:Prevotella / Q000235:genetics*; D012329:RNA, Bacterial / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; C063842:dnaK protein, E coli