title: Factors influencing preferential utilization of RNA polymerase containing sigma-38 in stationary-phase gene expression in Escherichia coli.
abstract: In order to understand the molecular basis of selective expression of stationary-phase genes by RNA polymerase containing sigma38 (Esigma38) in Escherichia coli, we examined transcription from the stationary-phase promoters, katEP, bolAP, hdeABP, csgBAP, and mcbP, in vivo and in vitro. Although these promoters are preferentially recognized in vivo by Esigma38, they are transcribed in vitro by both Esigma38 and Esigma70 containing the major exponential sigma, sigma70. In the presence of high concentrations of glutamate salts, however, only Esigma38 was able to efficiently transcribe from these promoters, which supports the concept that the promoter selectivity of sigma38-containing RNA polymerase is observed only under specific reaction conditions. The examination of 6S RNA, which is encoded by the ssr1 gene in vivo, showed that it reduced Esigma70 activity during the stationary phase, but this reduction of activity did not result in the elevation of Esigma38 activity. Thus, the preferential expression of stationary-phase genes by Esigma38 is unlikely the consequence of selective inhibition of Esigma70 by 6S RNA.
authors.affiliation: Genome Research Center for Enteropathogenic Bacteria, and Dept. of Microbiology, Chonnam National University Medical College, Hak-1-Dong, Dong-Gu, Kwang-Ju, Korea 501-746.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Kim
authors.forename: Min-Sang
authors.initials: MS
authors.lastname: Shin
authors.forename: Joon Haeng
authors.initials: JH
authors.lastname: Rhee
authors.forename: Hyon E
authors.initials: HE
authors.lastname: Choy
mesh_terms: D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D019677:Artificial Gene Fusion; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001430:Bacteriocins / Q000235:genetics / Q000378:metabolism; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D017930:Genes, Reporter / Q000235:genetics / Q000502:physiology; D018698:Glutamic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000502:physiology; D012329:RNA, Bacterial / Q000032:analysis / Q000302:isolation & purification / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis / Q000302:isolation & purification; D022661:RNA, Untranslated; D012808:Sigma Factor / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects* / Q000502:physiology; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: C411065:6S RNA; D001426:Bacterial Proteins; D001430:Bacteriocins; C109182:CsgB protein, E coli; D004791:Enzyme Inhibitors; D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D022661:RNA, Untranslated; D012808:Sigma Factor; C489688:csgA protein, E coli; C084501:hdeA protein, E coli; C084502:hdeB protein, E coli; C069567:sigma factor KatF protein, Bacteria; C020411:microcin; C077481:Crl protein, Bacteria; D018698:Glutamic Acid; C102664:hydroperoxidase II; D002374:Catalase; D012321:DNA-Directed RNA Polymerases; D001616:beta-Galactosidase