You are here
Identification of sigma S-regulated genes in Salmonella typhimurium: complementary regulatory interactions between sigma S and cyclic AMP receptor protein.
Title | Identification of sigma S-regulated genes in Salmonella typhimurium: complementary regulatory interactions between sigma S and cyclic AMP receptor protein. |
Publication Type | Journal Article |
Year of Publication | 1996 |
Authors | Fang, FC, Chen, CY, Guiney, DG, Xu, Y |
Journal | J Bacteriol |
Volume | 178 |
Issue | 17 |
Pagination | 5112-20 |
Date Published | 1996 Sep |
ISSN | 0021-9193 |
Keywords | Amino Acid Sequence, Animals, Arabinose, Bacterial Proteins, Blotting, Western, Cloning, Molecular, Female, Gene Expression Regulation, Bacterial, Genetic Complementation Test, Isopropyl Thiogalactoside, Lac Operon, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Osmolar Concentration, Receptors, Cyclic AMP, Salmonella typhimurium, Sigma Factor, Virulence |
Abstract | sigma S (RpoS)-regulated lacZ transcriptional fusions in Salmonella typhimurium were identified from a MudJ transposon library by placing the rpoS gene under the control of the araBAD promoter and detecting lacZ expression in the presence or absence of arabinose supplementation. Western blot (immunoblot) analysis of bacteria carrying PBAD::rpoS demonstrated arabinose-dependent rpoS expression during all phases of growth. sigma S-dependent gene expression of individual gene fusions was confirmed by P22-mediated transduction of the MudJ insertions into wild-type or rpoS backgrounds. Analysis of six insertions revealed the known sigma S-regulated gene otsA, as well as five novel loci. Each of these genes is maximally expressed in stationary phase, and all but one show evidence of cyclic AMP receptor protein-dependent repression during logarithmic growth which is relieved in stationary phase. For these genes, as well as for the sigma S-regulated spvB plasmid virulence gene, a combination of rpoS overexpression and crp inactivation can result in high-level expression during logarithmic growth. The approach used to identify sigma S-regulated genes in this study provides a general method for the identification of genes controlled by trans-acting regulatory factors. |
Alternate Journal | J. Bacteriol. |
PubMed ID | 8752327 |
PubMed Central ID | PMC178306 |
Grant List | AI32178 / AI / NIAID NIH HHS / United States AI32463 / AI / NIAID NIH HHS / United States |