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. 1991 May 11;19(9):2281–2287. doi: 10.1093/nar/19.9.2281

Influence of a mutation in the putative nucleotide binding site of the nitrogen regulatory protein NTRC on its positive control function.

S Austin 1, C Kundrot 1, R Dixon 1
PMCID: PMC329431  PMID: 2041769

Abstract

A mutation, serine 170 to alanine, in the proposed ATP binding site of the activator protein NTRC prevents transcriptional activation at sigma 54-dependent promoters both in vivo and in vitro. The rate of phosphorylation of the mutant protein by NTRB and the stability of mutant NTRC-phosphate were similar to those of wild-type NTRC. The phosphorylated mutant protein shows only a slight decrease in affinity (around 2-fold) for tandem NTRC binding sites in the Klebsiella pneumoniae nifL promoter suggesting that the mutation primarily influences the positive control function of NTRC. Moreover the mutant protein is trans dominant to the wild-type protein with respect to transcriptional activation at both the glnAp2 and nifL promoters. In vitro footprinting experiments reveal that the mutant protein is unable to catalyse isomerisation of closed promoter complexes between sigma 54-RNA polymerase and the nifL promoter to open promoter complexes. However, the mutant protein retains the ability to increase the occupancy of the -24, -12 region by sigma 54-RNA polymerase, forming closed complexes at the nifL promoter, which are not detectable in the absence of NTRC. These data support a model in which the activator influences the formation of closed complexes at the nifL promoter in addition to its role in catalysing open complex formation.

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Selected References

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  1. Austin S., Henderson N., Dixon R. Requirements for transcriptional activation in vitro of the nitrogen-regulated glnA and nifLA promoters from Klebsiella pneumoniae: dependence on activator concentration. Mol Microbiol. 1987 Jul;1(1):92–100. doi: 10.1111/j.1365-2958.1987.tb00532.x. [DOI] [PubMed] [Google Scholar]
  2. Beynon J., Cannon M., Buchanan-Wollaston V., Cannon F. The nif promoters of Klebsiella pneumoniae have a characteristic primary structure. Cell. 1983 Sep;34(2):665–671. doi: 10.1016/0092-8674(83)90399-9. [DOI] [PubMed] [Google Scholar]
  3. Borowiec J. A., Zhang L., Sasse-Dwight S., Gralla J. D. DNA supercoiling promotes formation of a bent repression loop in lac DNA. J Mol Biol. 1987 Jul 5;196(1):101–111. doi: 10.1016/0022-2836(87)90513-4. [DOI] [PubMed] [Google Scholar]
  4. Buck M., Cannon W. Mutations in the RNA polymerase recognition sequence of the Klebsiella pneumoniae nifH promoter permitting transcriptional activation in the absence of NifA binding to upstream activator sequences. Nucleic Acids Res. 1989 Apr 11;17(7):2597–2612. doi: 10.1093/nar/17.7.2597. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Casadaban M. J., Cohen S. N. Analysis of gene control signals by DNA fusion and cloning in Escherichia coli. J Mol Biol. 1980 Apr;138(2):179–207. doi: 10.1016/0022-2836(80)90283-1. [DOI] [PubMed] [Google Scholar]
  6. Contreras A., Drummond M. The effect on the function of the transcriptional activator NtrC from Klebsiella pneumoniae of mutations in the DNA-recognition helix. Nucleic Acids Res. 1988 May 11;16(9):4025–4039. doi: 10.1093/nar/16.9.4025. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Dixon R. A., Henderson N. C., Austin S. DNA supercoiling and aerobic regulation of transcription from the Klebsiella pneumoniae nifLA promoter. Nucleic Acids Res. 1988 Nov 11;16(21):9933–9946. doi: 10.1093/nar/16.21.9933. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Dixon R. Tandem promoters determine regulation of the Klebsiella pneumoniae glutamine synthetase (glnA) gene. Nucleic Acids Res. 1984 Oct 25;12(20):7811–7830. doi: 10.1093/nar/12.20.7811. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Dreusicke D., Schulz G. E. The switch between two conformations of adenylate kinase. J Mol Biol. 1988 Oct 20;203(4):1021–1028. doi: 10.1016/0022-2836(88)90126-x. [DOI] [PubMed] [Google Scholar]
  10. Drummond M. H., Contreras A., Mitchenall L. A. The function of isolated domains and chimaeric proteins constructed from the transcriptional activators NifA and NtrC of Klebsiella pneumoniae. Mol Microbiol. 1990 Jan;4(1):29–37. doi: 10.1111/j.1365-2958.1990.tb02012.x. [DOI] [PubMed] [Google Scholar]
  11. Drummond M., Whitty P., Wootton J. Sequence and domain relationships of ntrC and nifA from Klebsiella pneumoniae: homologies to other regulatory proteins. EMBO J. 1986 Feb;5(2):441–447. doi: 10.1002/j.1460-2075.1986.tb04230.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Elliott T., Geiduschek E. P. Defining a bacteriophage T4 late promoter: absence of a "-35" region. Cell. 1984 Jan;36(1):211–219. doi: 10.1016/0092-8674(84)90091-6. [DOI] [PubMed] [Google Scholar]
  13. Fry D. C., Kuby S. A., Mildvan A. S. ATP-binding site of adenylate kinase: mechanistic implications of its homology with ras-encoded p21, F1-ATPase, and other nucleotide-binding proteins. Proc Natl Acad Sci U S A. 1986 Feb;83(4):907–911. doi: 10.1073/pnas.83.4.907. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Kleiner D., Paul W., Merrick M. J. Construction of multicopy expression vectors for regulated over-production of proteins in Klebsiella pneumoniae and other enteric bacteria. J Gen Microbiol. 1988 Jul;134(7):1779–1784. doi: 10.1099/00221287-134-7-1779. [DOI] [PubMed] [Google Scholar]
  15. Kustu S., Santero E., Keener J., Popham D., Weiss D. Expression of sigma 54 (ntrA)-dependent genes is probably united by a common mechanism. Microbiol Rev. 1989 Sep;53(3):367–376. doi: 10.1128/mr.53.3.367-376.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. MacNeil T., Roberts G. P., MacNeil D., Tyler B. The products of glnL and glnG are bifunctional regulatory proteins. Mol Gen Genet. 1982;188(2):325–333. doi: 10.1007/BF00332696. [DOI] [PubMed] [Google Scholar]
  17. Minchin S. D., Austin S., Dixon R. A. The role of activator binding sites in transcriptional control of the divergently transcribed nifF and nifLA promoters from Klebsiella pneumoniae. Mol Microbiol. 1988 Jul;2(4):433–442. doi: 10.1111/j.1365-2958.1988.tb00049.x. [DOI] [PubMed] [Google Scholar]
  18. Minchin S. D., Austin S., Dixon R. A. Transcriptional activation of the Klebsiella pneumoniae nifLA promoter by NTRC is face-of-the-helix dependent and the activator stabilizes the interaction of sigma 54-RNA polymerase with the promoter. EMBO J. 1989 Nov;8(11):3491–3499. doi: 10.1002/j.1460-2075.1989.tb08514.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Morett E., Buck M. In vivo studies on the interaction of RNA polymerase-sigma 54 with the Klebsiella pneumoniae and Rhizobium meliloti nifH promoters. The role of NifA in the formation of an open promoter complex. J Mol Biol. 1989 Nov 5;210(1):65–77. doi: 10.1016/0022-2836(89)90291-x. [DOI] [PubMed] [Google Scholar]
  20. Morikawa K., la Cour T. F., Nyborg J., Rasmussen K. M., Miller D. L., Clark B. F. High resolution x-ray crystallographic analysis of a modified form of the elongation factor Tu: guanosine diphosphate complex. J Mol Biol. 1978 Nov 5;125(3):325–338. doi: 10.1016/0022-2836(78)90406-0. [DOI] [PubMed] [Google Scholar]
  21. Ninfa A. J., Reitzer L. J., Magasanik B. Initiation of transcription at the bacterial glnAp2 promoter by purified E. coli components is facilitated by enhancers. Cell. 1987 Sep 25;50(7):1039–1046. doi: 10.1016/0092-8674(87)90170-x. [DOI] [PubMed] [Google Scholar]
  22. Parsonage D., Al-Shawi M. K., Senior A. E. Directed mutations of the strongly conserved lysine 155 in the catalytic nucleotide-binding domain of beta-subunit of F1-ATPase from Escherichia coli. J Biol Chem. 1988 Apr 5;263(10):4740–4744. [PubMed] [Google Scholar]
  23. Popham D. L., Szeto D., Keener J., Kustu S. Function of a bacterial activator protein that binds to transcriptional enhancers. Science. 1989 Feb 3;243(4891):629–635. doi: 10.1126/science.2563595. [DOI] [PubMed] [Google Scholar]
  24. Ronson C. W., Astwood P. M., Nixon B. T., Ausubel F. M. Deduced products of C4-dicarboxylate transport regulatory genes of Rhizobium leguminosarum are homologous to nitrogen regulatory gene products. Nucleic Acids Res. 1987 Oct 12;15(19):7921–7934. doi: 10.1093/nar/15.19.7921. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Saraste M., Sibbald P. R., Wittinghofer A. The P-loop--a common motif in ATP- and GTP-binding proteins. Trends Biochem Sci. 1990 Nov;15(11):430–434. doi: 10.1016/0968-0004(90)90281-f. [DOI] [PubMed] [Google Scholar]
  26. Sasse-Dwight S., Gralla J. D. KMnO4 as a probe for lac promoter DNA melting and mechanism in vivo. J Biol Chem. 1989 May 15;264(14):8074–8081. [PubMed] [Google Scholar]
  27. Sasse-Dwight S., Gralla J. D. Probing the Escherichia coli glnALG upstream activation mechanism in vivo. Proc Natl Acad Sci U S A. 1988 Dec;85(23):8934–8938. doi: 10.1073/pnas.85.23.8934. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Tuli R., Merrick M. J. Over-production and characterization of the nifA gene product of Klebsiella pneumoniae--the transcriptional activator of nif gene expression. J Gen Microbiol. 1988 Feb;134(2):425–432. doi: 10.1099/00221287-134-2-425. [DOI] [PubMed] [Google Scholar]
  29. Walker J. E., Saraste M., Runswick M. J., Gay N. J. Distantly related sequences in the alpha- and beta-subunits of ATP synthase, myosin, kinases and other ATP-requiring enzymes and a common nucleotide binding fold. EMBO J. 1982;1(8):945–951. doi: 10.1002/j.1460-2075.1982.tb01276.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. 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]
  31. la Cour T. F., Nyborg J., Thirup S., Clark B. F. Structural details of the binding of guanosine diphosphate to elongation factor Tu from E. coli as studied by X-ray crystallography. EMBO J. 1985 Sep;4(9):2385–2388. doi: 10.1002/j.1460-2075.1985.tb03943.x. [DOI] [PMC free article] [PubMed] [Google Scholar]

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