Activation of the dephosphorylation of nitrogen regulator I-phosphate of Escherichia coli.
The transcription of sigma 54 RNA polymerase-dependent nitrogen-regulated genes is activated by nitrogen regulator I (NRI)-phosphate. The kinase NRII is responsible for the phosphorylation of NRI. It has been shown that NRII also has the ability to dephosphorylate NRI-phosphate but only when PII is present at a concentration greatly in excess of that of NRII. We have now shown that glutamate enables PII to stimulate the dephosphorylation of NRI-phosphate when present in equimolar concentration with NRII. This effect of glutamate appears to be a backup control that becomes effective when the normal regulation of PII activity is disabled.
Department of Biology, Massachusetts Institute of Technology, Cambridge, 02139.
J
J
Liu
B
B
Magasanik
D001426:Bacterial Proteins / Q000187:drug effects / Q000378:metabolism*; D003035:Cobalt / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000201:enzymology / Q000378:metabolism*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005974:Glutamate-Ammonia Ligase / Q000096:biosynthesis; D018698:Glutamic Acid / Q000494:pharmacology; D007656:Ketoglutaric Acids / Q000494:pharmacology; D051922:PII Nitrogen Regulatory Proteins; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D051877:RNA Polymerase Sigma 54; D012808:Sigma Factor / Q000378:metabolism; D015534:Trans-Activators; D014157:Transcription Factors
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D007656:Ketoglutaric Acids; D051922:PII Nitrogen Regulatory Proteins; D012808:Sigma Factor; D015534:Trans-Activators; D014157:Transcription Factors; C497876:glnG protein, E coli; C497751:rpoN protein, E coli; D003035:Cobalt; D018698:Glutamic Acid; C404143:PIID regulatory protein, Bacteria; D011494:Protein Kinases; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54; D005974:Glutamate-Ammonia Ligase