Crosstalk between bacterial chemotaxis signal transduction proteins and regulators of transcription of the Ntr regulon: evidence that nitrogen assimilation and chemotaxis are controlled by a common phosphotransfer mechanism.
We demonstrate by using purified bacterial components that the protein kinases that regulate chemotaxis and transcription of nitrogen-regulated genes, CheA and NRII, respectively, have cross-specificities: CheA can phosphorylate the Ntr transcription factor NRI and thereby activate transcription from the nitrogen-regulated glnA promoter, and NRII can phosphorylate CheY. In addition, we find that a high intracellular concentration of a highly active mutant form of NRII can suppress the smooth-swimming phenotype of a cheA mutant. These results argue strongly that sensory transduction in the Ntr and Che systems involves a common protein phosphotransfer mechanism.
D001426:Bacterial Proteins; D002630:Chemotactic Factors / Q000235:genetics*; D002633:Chemotaxis; D002850:Chromatography, Gel; D003429:Cross Reactions; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins; D000071677:Histidine Kinase; D008565:Membrane Proteins / Q000235:genetics*; D000072236:Methyl-Accepting Chemotaxis Proteins; D009154:Mutation; D009584:Nitrogen / Q000378:metabolism*; D010641:Phenotype; D010710:Phosphates / Q000378:metabolism; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D012486:Salmonella typhimurium / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D014161:Transduction, Genetic
D001426:Bacterial Proteins; D002630:Chemotactic Factors; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; D010710:Phosphates; C000607606:cheY protein, E coli; D000071677:Histidine Kinase; C000607608:cheA protein, E coli; D009584:Nitrogen