Skip to main content
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1993 Nov;175(21):7024–7032. doi: 10.1128/jb.175.21.7024-7032.1993

Mechanism of autophosphorylation of Escherichia coli nitrogen regulator II (NRII or NtrB): trans-phosphorylation between subunits.

E G Ninfa 1, M R Atkinson 1, E S Kamberov 1, A J Ninfa 1
PMCID: PMC206830  PMID: 8226644

Abstract

Nitrogen regulator II (NRII or NtrB) is a homodimeric signal-transducing protein kinase/phosphatase responsible for the transcriptional regulation of the Ntr regulon in Escherichia coli. NRII is a member of a large family of proteins that are part of the related two-component signal transduction systems. We studied the mechanism of NRII autophosphorylation by using purified components. Alteration of the site of NRII autophosphorylation to asparagine (H-139-->N [H139N]) or deletion of the C-terminal 59 amino acids of NRII (ter291) resulted in proteins that were not autophosphorylated upon incubation with ATP. Alteration of glycine 313 to alanine resulted in a protein (G313A) that was phosphorylated to a lesser extent than the wild-type protein. Unlike wild-type NRII and H139N, G313A could not be efficiently cross-linked to [alpha-32P]ATP, suggesting that the G313A mutation affects nucleotide binding. Fusion of maltose-binding protein (MBP) to the N-terminal end of NRII resulted in a protein (MBP-NRII) that autophosphorylated normally. We developed a procedure for forming mixed dimers in vitro from these proteins. In mixed dimers consisting of MBP-NRII and H139N, only the MBP-NRII subunit is phosphorylated. In contrast, in mixed dimers consisting of MBP-NRII and G313A, phosphorylation is predominantly on the G313A subunit. We also demonstrated that the G313A and H139N proteins could complement for the autophosphorylation reaction when they were treated so as to permit the formation of mixed dimers and that the wild-type and H139N proteins could phosphorylate the ter291 protein. These results indicate that the autophosphorylation reaction occurs within the dimer by a trans, intersubunit mechanism in which one subunit binds ATP and phosphorylates the other subunit.

Full text

PDF
7024

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Adler S. P., Purich D., Stadtman E. R. Cascade control of Escherichia coli glutamine synthetase. Properties of the PII regulatory protein and the uridylyltransferase-uridylyl-removing enzyme. J Biol Chem. 1975 Aug 25;250(16):6264–6272. [PubMed] [Google Scholar]
  2. Atkinson M. R., Ninfa A. J. Mutational analysis of the bacterial signal-transducing protein kinase/phosphatase nitrogen regulator II (NRII or NtrB). J Bacteriol. 1993 Nov;175(21):7016–7023. doi: 10.1128/jb.175.21.7016-7023.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bueno R., Pahel G., Magasanik B. Role of glnB and glnD gene products in regulation of the glnALG operon of Escherichia coli. J Bacteriol. 1985 Nov;164(2):816–822. doi: 10.1128/jb.164.2.816-822.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hunt T. P., Magasanik B. Transcription of glnA by purified Escherichia coli components: core RNA polymerase and the products of glnF, glnG, and glnL. Proc Natl Acad Sci U S A. 1985 Dec;82(24):8453–8457. doi: 10.1073/pnas.82.24.8453. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Keener J., Kustu S. Protein kinase and phosphoprotein phosphatase activities of nitrogen regulatory proteins NTRB and NTRC of enteric bacteria: roles of the conserved amino-terminal domain of NTRC. Proc Natl Acad Sci U S A. 1988 Jul;85(14):4976–4980. doi: 10.1073/pnas.85.14.4976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Ninfa A. J., Bennett R. L. Identification of the site of autophosphorylation of the bacterial protein kinase/phosphatase NRII. J Biol Chem. 1991 Apr 15;266(11):6888–6893. [PubMed] [Google Scholar]
  7. Ninfa A. J., Magasanik B. Covalent modification of the glnG product, NRI, by the glnL product, NRII, regulates the transcription of the glnALG operon in Escherichia coli. Proc Natl Acad Sci U S A. 1986 Aug;83(16):5909–5913. doi: 10.1073/pnas.83.16.5909. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Ninfa A. J. Protein phosphorylation and the regulation of cellular processes by the homologous two-component regulatory systems of bacteria. Genet Eng (N Y) 1991;13:39–72. doi: 10.1007/978-1-4615-3760-1_2. [DOI] [PubMed] [Google Scholar]
  9. Ninfa A. J., Ueno-Nishio S., Hunt T. P., Robustell B., Magasanik B. Purification of nitrogen regulator II, the product of the glnL (ntrB) gene of Escherichia coli. J Bacteriol. 1986 Nov;168(2):1002–1004. doi: 10.1128/jb.168.2.1002-1004.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Ninfa E. G., Stock A., Mowbray S., Stock J. Reconstitution of the bacterial chemotaxis signal transduction system from purified components. J Biol Chem. 1991 May 25;266(15):9764–9770. [PubMed] [Google Scholar]
  11. Parkinson J. S., Kofoid E. C. Communication modules in bacterial signaling proteins. Annu Rev Genet. 1992;26:71–112. doi: 10.1146/annurev.ge.26.120192.000443. [DOI] [PubMed] [Google Scholar]
  12. Rhee S. G., Park S. C., Koo J. H. The role of adenylyltransferase and uridylyltransferase in the regulation of glutamine synthetase in Escherichia coli. Curr Top Cell Regul. 1985;27:221–232. doi: 10.1016/b978-0-12-152827-0.50026-8. [DOI] [PubMed] [Google Scholar]
  13. Sanders D. A., Gillece-Castro B. L., Burlingame A. L., Koshland D. E., Jr Phosphorylation site of NtrC, a protein phosphatase whose covalent intermediate activates transcription. J Bacteriol. 1992 Aug;174(15):5117–5122. doi: 10.1128/jb.174.15.5117-5122.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Schauder B., Blöcker H., Frank R., McCarthy J. E. Inducible expression vectors incorporating the Escherichia coli atpE translational initiation region. Gene. 1987;52(2-3):279–283. doi: 10.1016/0378-1119(87)90054-0. [DOI] [PubMed] [Google Scholar]
  15. Smith R. A., Parkinson J. S. Overlapping genes at the cheA locus of Escherichia coli. Proc Natl Acad Sci U S A. 1980 Sep;77(9):5370–5374. doi: 10.1073/pnas.77.9.5370. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Stock J. B., Ninfa A. J., Stock A. M. Protein phosphorylation and regulation of adaptive responses in bacteria. Microbiol Rev. 1989 Dec;53(4):450–490. doi: 10.1128/mr.53.4.450-490.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Swanson R. V., Bourret R. B., Simon M. I. Intermolecular complementation of the kinase activity of CheA. Mol Microbiol. 1993 May;8(3):435–441. doi: 10.1111/j.1365-2958.1993.tb01588.x. [DOI] [PubMed] [Google Scholar]
  18. Weiss V., Magasanik B. Phosphorylation of nitrogen regulator I (NRI) of Escherichia coli. Proc Natl Acad Sci U S A. 1988 Dec;85(23):8919–8923. doi: 10.1073/pnas.85.23.8919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Wolfe A. J., Stewart R. C. The short form of the CheA protein restores kinase activity and chemotactic ability to kinase-deficient mutants. Proc Natl Acad Sci U S A. 1993 Feb 15;90(4):1518–1522. doi: 10.1073/pnas.90.4.1518. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Yang Y., Inouye M. Intermolecular complementation between two defective mutant signal-transducing receptors of Escherichia coli. Proc Natl Acad Sci U S A. 1991 Dec 15;88(24):11057–11061. doi: 10.1073/pnas.88.24.11057. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES