title: Effect of glpT and glpD mutations on expression of the phoA gene in Escherichia coli.
abstract: In vivo 31P nuclear magnetic resonance analysis of Escherichia coli cells showed that the intracellular concentration of P(i) remained constant in wild-type and in a glpT mutant strain whether the cells were grown on excess (2 mM) P(i) or sn-glycerol-3-phosphate as a phosphate source. The function of the phoA promoter (measured by beta-galactosidase activity in a phoA-lacZ fusion strain) was repressed when glpT+ cells were utilizing sn-glycerol-3-phosphate as the sole source of phosphate. These cells were devoid of alkaline phosphatase activity. However, the phoA promoter was fully active in a glpT mutant. These results indicated that the repression of the enzyme synthesis was not due to a variation in the level of cytoplasmic P(i) but was due to the P(i) excreted into the periplasm and/or to the medium.
authors.affiliation: Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: N N
authors.initials: NN
authors.lastname: Rao
authors.forename: M F
authors.initials: MF
authors.lastname: Roberts
authors.forename: A
authors.initials: A
authors.lastname: Torriani
authors.forename: J
authors.initials: J
authors.lastname: Yashphe
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D004794:Enzyme Repression; D004926:Escherichia coli / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D005988:Glyceric Acids / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D009154:Mutation; D010710:Phosphates / Q000378:metabolism; D010712:Phosphatidic Acids / Q000378:metabolism; D010759:Phosphorus Isotopes; D011401:Promoter Regions, Genetic / Q000235:genetics; D011993:Recombinant Fusion Proteins; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D005988:Glyceric Acids; D010710:Phosphates; D010712:Phosphatidic Acids; D010759:Phosphorus Isotopes; D011993:Recombinant Fusion Proteins; C005156:3-phosphoglycerate; D000469:Alkaline Phosphatase; D001616:beta-Galactosidase