title: RpoS-regulated genes of Escherichia coli identified by random lacZ fusion mutagenesis.
abstract: RpoS is a conserved alternative sigma factor that regulates the expression of many stress response genes in Escherichia coli. The RpoS regulon is large but has not yet been completely characterized. In this study, we report the identification of over 100 RpoS-dependent fusions in a genetic screen based on the differential expression of an operon-lacZ fusion bank in rpoS mutant and wild-type backgrounds. Forty-eight independent gene fusions were identified, including several in well-characterized RpoS-regulated genes, such as osmY, katE, and otsA. Many of the other fusions mapped to genes of unknown function or to genes that were not previously known to be under RpoS control. Based on the homology to other known bacterial genes, some of the RpoS-regulated genes of unknown functions are likely important in nutrient scavenging.
authors.affiliation: Department of Biology, McMaster University, 1280 Main St. West, Hamilton, Ontario, Canada, L8S 4K1.
authors.forename: Somalinga R V
authors.initials: SR
authors.lastname: Vijayakumar
authors.forename: Mark G
authors.initials: MG
authors.lastname: Kirchhof
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Patten
authors.forename: Herb E
authors.initials: HE
authors.lastname: Schellhorn
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D005821:Genetic Techniques; D007763:Lac Operon; D016296:Mutagenesis; D009876:Operon; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria