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. 1991 Oct;173(20):6355–6363. doi: 10.1128/jb.173.20.6355-6363.1991

Role of multiple environmental stimuli in control of transcription from a nitrogen-regulated promoter in Escherichia coli with weak or no activator-binding sites.

B L Schneider 1, S P Shiau 1, L J Reitzer 1
PMCID: PMC208967  PMID: 1680849

Abstract

Nitrogen regulator I (NRI [or NtrC])-phosphate stimulates transcription from the glnAp2 promoter of the glnALG operon in enteric bacteria. Unlike most activators, NRI-phosphate can stimulate transcription without apparent activator binding sites. We observed that when lacZ was controlled by a minimal glnAp2 promoter (without NRI binding sites) in Escherichia coli, lacZ expression was regulated by two different stimuli, the nitrogen status of the medium and the particular amino acid used as a nitrogen source. The latter stimulus did not affect the activity of the wild-type glnAp2 promoter, which has two high-affinity NRI binding sites. We present several lines of evidence that suggest that the concentration of NRI-phosphate limits the activity of the minimal glnAp2 promoter in vivo. Our results also suggest that nitrogen regulator II-dependent phosphorylation of NRI cannot account for the proposed variations in the concentration of NRI-phosphate. Therefore, to account for the regulation of the minimal glnAp2 promoter by two environmental stimuli, we propose that at least two protein kinases phosphorylate NRI during nitrogen-limited growth. We isolated and characterized mutants in which NRI could not stimulate transcription from the minimal glnAp2 promoter but could activate transcription from the wild-type glnAp2 promoter. These mutants could not utilize arginine or proline as a nitrogen source, suggesting that degradation of some nitrogen sources may require transcription from promoters similar to the minimal glnAp2 promoter.

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Selected References

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

  1. Backman K., Chen Y. M., Magasanik B. Physical and genetic characterization of the glnA--glnG region of the Escherichia coli chromosome. Proc Natl Acad Sci U S A. 1981 Jun;78(6):3743–3747. doi: 10.1073/pnas.78.6.3743. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Brown E. A., D'Ari R., Newman E. B. A relationship between L-serine degradation and methionine biosynthesis in Escherichia coli K12. J Gen Microbiol. 1990 Jun;136(6):1017–1023. doi: 10.1099/00221287-136-6-1017. [DOI] [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. Burbulys D., Trach K. A., Hoch J. A. Initiation of sporulation in B. subtilis is controlled by a multicomponent phosphorelay. Cell. 1991 Feb 8;64(3):545–552. doi: 10.1016/0092-8674(91)90238-t. [DOI] [PubMed] [Google Scholar]
  5. Castaño I., Bastarrachea F. glnF-lacZ fusions in Escherichia coli: studies on glnF expression and its chromosomal orientation. Mol Gen Genet. 1984;195(1-2):228–233. doi: 10.1007/BF00332751. [DOI] [PubMed] [Google Scholar]
  6. Chen Y. M., Backman K., Magasanik B. Characterization of a gene, glnL, the product of which is involved in the regulation of nitrogen utilization in Escherichia coli. J Bacteriol. 1982 Apr;150(1):214–220. doi: 10.1128/jb.150.1.214-220.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Hirschman J., Wong P. K., Sei K., Keener J., Kustu S. Products of nitrogen regulatory genes ntrA and ntrC of enteric bacteria activate glnA transcription in vitro: evidence that the ntrA product is a sigma factor. Proc Natl Acad Sci U S A. 1985 Nov;82(22):7525–7529. doi: 10.1073/pnas.82.22.7525. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Hong J. S., Ames B. N. Localized mutagenesis of any specific small region of the bacterial chromosome. Proc Natl Acad Sci U S A. 1971 Dec;68(12):3158–3162. doi: 10.1073/pnas.68.12.3158. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Hsu L. M., Giannini J. K., Leung T. W., Crosthwaite J. C. Upstream sequence activation of Escherichia coli argT promoter in vivo and in vitro. Biochemistry. 1991 Jan 22;30(3):813–822. doi: 10.1021/bi00217a035. [DOI] [PubMed] [Google Scholar]
  10. 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]
  11. 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]
  12. Kustu S., Burton D., Garcia E., McCarter L., McFarland N. Nitrogen control in Salmonella: regulation by the glnR and glnF gene products. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4576–4580. doi: 10.1073/pnas.76.9.4576. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Magasanik B. Genetic control of nitrogen assimilation in bacteria. Annu Rev Genet. 1982;16:135–168. doi: 10.1146/annurev.ge.16.120182.001031. [DOI] [PubMed] [Google Scholar]
  14. McFarland N., McCarter L., Artz S., Kustu S. Nitrogen regulatory locus "glnR" of enteric bacteria is composed of cistrons ntrB and ntrC: identification of their protein products. Proc Natl Acad Sci U S A. 1981 Apr;78(4):2135–2139. doi: 10.1073/pnas.78.4.2135. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. 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]
  16. 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]
  17. Reitzer L. J., Magasanik B. Expression of glnA in Escherichia coli is regulated at tandem promoters. Proc Natl Acad Sci U S A. 1985 Apr;82(7):1979–1983. doi: 10.1073/pnas.82.7.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Reitzer L. J., Magasanik B. Transcription of glnA in E. coli is stimulated by activator bound to sites far from the promoter. Cell. 1986 Jun 20;45(6):785–792. doi: 10.1016/0092-8674(86)90553-2. [DOI] [PubMed] [Google Scholar]
  19. Reitzer L. J., Movsas B., Magasanik B. Activation of glnA transcription by nitrogen regulator I (NRI)-phosphate in Escherichia coli: evidence for a long-range physical interaction between NRI-phosphate and RNA polymerase. J Bacteriol. 1989 Oct;171(10):5512–5522. doi: 10.1128/jb.171.10.5512-5522.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Rothstein D. M., Pahel G., Tyler B., Magasanik B. Regulation of expression from the glnA promoter of Escherichia coli in the absence of glutamine synthetase. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7372–7376. doi: 10.1073/pnas.77.12.7372. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. 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]
  22. Schmitz G., Nikaido K., Ames G. F. Regulation of a transport operon promoter in Salmonella typhimurium: identification of sites essential for nitrogen regulation. Mol Gen Genet. 1988 Dec;215(1):107–117. doi: 10.1007/BF00331311. [DOI] [PubMed] [Google Scholar]
  23. Su W., Porter S., Kustu S., Echols H. DNA-looping and enhancer activity: association between DNA-bound NtrC activator and RNA polymerase at the bacterial glnA promoter. Proc Natl Acad Sci U S A. 1990 Jul;87(14):5504–5508. doi: 10.1073/pnas.87.14.5504. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Wedel A., Weiss D. S., Popham D., Dröge P., Kustu S. A bacterial enhancer functions to tether a transcriptional activator near a promoter. Science. 1990 Apr 27;248(4954):486–490. doi: 10.1126/science.1970441. [DOI] [PubMed] [Google Scholar]
  25. Weglenski P., Ninfa A. J., Ueno-Nishio S., Magasanik B. Mutations in the glnG gene of Escherichia coli that result in increased activity of nitrogen regulator I. J Bacteriol. 1989 Aug;171(8):4479–4485. doi: 10.1128/jb.171.8.4479-4485.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Wong P. K., Popham D., Keener J., Kustu S. In vitro transcription of the nitrogen fixation regulatory operon nifLA of Klebsiella pneumoniae. J Bacteriol. 1987 Jun;169(6):2876–2880. doi: 10.1128/jb.169.6.2876-2880.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]

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