Identification and characterization of stationary phase-inducible genes in Escherichia coli.
During transition into stationary phase a large set of proteins is induced in Escherichia coli. Only a minority of the corresponding genes has been identified so far. Using the lambda placMu system and a plate screen for carbon starvation-induced fusion activity, a series of chromosomal lacZ fusions (csi::lacZ) was isolated. In complex medium these fusions were induced either during late exponential phase or during entry into stationary phase. csi::lacZ expression in minimal media in response to starvation for carbon, nitrogen and phosphate sources and the roles of global regulators such as the alternative sigma factor sigma s (encoded by rpoS), cAMP/CRP and the relA gene product were investigated. The results show that almost every fusion exhibits its own characteristic pattern of expression, suggesting a complex control of stationary phase-inducible genes that involves various combinations of regulatory mechanisms for different genes. All fusions were mapped to the E. coli chromosome. Using fine mapping by Southern hybridization, cloning, sequencing and/or phenotypic analysis, csi-5, csi-17, and csi-18 could be localized in osmY (encoding a periplasmic protein), glpD (aerobic glycerol-3-phosphate dehydrogenase) and glgA (glycogen synthase), respectively. The other fusions seem to specify novel genes now designated csiA through to csiF. csi-17(glpD)::lacZ was shown to produce its own glucose-starvation induction, thus illustrating the intricacies of gene-fusion technology when applied to the study of gene regulation.
Weichart
D
D
Department of Biology, University of Konstanz, Germany.
Lange
R
R
Henneberg
N
N
Hengge-Aronis
R
R
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics; D002455:Cell Division; D002874:Chromosome Mapping; D000242:Cyclic AMP / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D005947:Glucose / Q000378:metabolism; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics; D006006:Glycogen Synthase / Q000235:genetics; D007763:Lac Operon; D033902:Periplasmic Binding Proteins; D011993:Recombinant Fusion Proteins; D012808:Sigma Factor / Q000378:metabolism
D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D033902:Periplasmic Binding Proteins; D011993:Recombinant Fusion Proteins; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria; C074783:osmY protein, E coli; D000242:Cyclic AMP; D005993:Glycerolphosphate Dehydrogenase; D006006:Glycogen Synthase; D005947:Glucose