1887

Abstract

uses glutamine as the best source of nitrogen. In the absence of glutamine, alternative nitrogen sources such as ammonium can be used. Ammonium utilization involves the uptake of the gas or the ammonium ion, the synthesis of glutamine by the glutamine synthetase and the recycling of the glutamate by the glutamate synthase. In this work, ammonium transport in . was studied. At high ammonium concentrations, a large fraction of the ammonium is present as ammonia, which may enter the cell via diffusion. In contrast, the ammonium transporter NrgA is required for ammonium utilization at low concentrations or at low pH values when the equilibrium between uncharged ammonia and the ammonium ion is shifted towards ammonium. Moreover, a functional NrgA is essential for the transport of the ammonium analogue methylammonium. NrgA is encoded in the operon. The product of the second gene, NrgB, is a member of the PII family of regulatory proteins. In contrast to PII proteins from other organisms, there is no indication for a covalent modification of NrgB in response to the nitrogen supply of the cell. It is demonstrated here that NrgB is localized at the membrane, most likely in association with the ammonium transporter NrgA. The presence of a functional NrgB is required for full-level expression of the operon in response to nitrogen limitation, suggesting that NrgB might relay the information on ammonium availability to downstream regulatory factors and thus fine-tune their activity.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.26512-0
2003-11-01
2024-04-18
Loading full text...

Full text loading...

/deliver/fulltext/micro/149/11/mic1493289.html?itemId=/content/journal/micro/10.1099/mic.0.26512-0&mimeType=html&fmt=ahah

References

  1. Arcondéguy T., Jack R., Merrick M. 2001; PII signal transduction proteins, pivotal players in microbial nitrogen control. Microbiol Mol Biol Rev 65:80–105
    [Google Scholar]
  2. Atkinson M. R., Fisher S. H. 1991; Identification of genes and gene products whose expression is activated during nitrogen-limited growth in Bacillus subtilis. J Bacteriol 173:23–27
    [Google Scholar]
  3. Atkinson M. R., Ninfa A. J. 1999; Characterization of the GlnK protein of Escherichia coli. Mol Microbiol 32:301–313
    [Google Scholar]
  4. Belitsky B. R. 2002; Biosynthesis of amino acids of the glutamate and aspartate families, alanine and polyamines. In Bacillus subtilis and its Closest Relatives: From Genes to Cells pp  203–231 Edited by Sonenshein A. L., Hoch J. A., Losick R. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  5. Belitsky B. R., Sonenshein A. L. 1998; Role and regulation of Bacillus subtilis glutamate dehydrogenase genes. J Bacteriol 180:6298–6305
    [Google Scholar]
  6. Belitsky B. R., Wray L. V. Jr, Fisher S. H., Bohannon D. E., Sonenshein A. L. 2000; Role of TnrA in nitrogen source-dependent repression of Bacillus subtilis glutamate synthase gene expression. J Bacteriol 182:5939–5947
    [Google Scholar]
  7. Blencke H.-M., Homuth G., Ludwig H., Mäder U., Hecker M., Stülke J. 2003; Transcriptional profiling of gene expression in response to glucose in Bacillus subtilis: regulation of the central metabolic pathways. Metab Eng 5:133–149
    [Google Scholar]
  8. Bohannon D. E., Sonenshein A. L. 1989; Positive regulation of glutamate biosynthesis in Bacillus subtilis. J Bacteriol 171:4718–4727
    [Google Scholar]
  9. Burkovski A. 2003; I do it my way: regulation of ammonium uptake and ammonium assimilation in Corynebacterium glutamicum. Arch Microbiol 179:83–88
    [Google Scholar]
  10. Coutts G., Thomas G., Blakey D., Merrick M. 2002; Membrane sequestration of the signal transduction protein GlnK by the ammonium transporter AmtB. EMBO J 21:536–545
    [Google Scholar]
  11. Faires N., Tobisch S., Bachem S., Martin-Verstraete I., Hecker M., Stülke J. 1999; The catabolite control protein CcpA controls ammonium assimilation in Bacillus subtilis. J Mol Microbiol Biotechnol 1:141–148
    [Google Scholar]
  12. Fink D., Falke D., Wohlleben W., Engels A. 1999; Nitrogen metabolism in Streptomyces coelicolor A3(2): modification of glutamine synthetase I by an adenylyltransferase. Microbiology 145:2313–2322
    [Google Scholar]
  13. Fink D., Weißschuh N., Reuther J., Wohlleben W., Engels A. 2002; Two transcriptional regulators GlnR and GlnRII are involved in regulation of nitrogen metabolism in Streptomyces coelicolor A3(2. Mol Microbiol 46:331–347
    [Google Scholar]
  14. Fisher S. H., Débarbouillé M. 2002; Nitrogen source utilization and its regulation. In Bacillus subtilis and its Closest Relatives: from Genes to Cells pp  181–191 Edited by Sonenshein A. L., Hoch J. A., Losick R. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  15. Fisher S. H., Brandenburg J. L., Wray L. V. Jr 2002; Mutations in Bacillus subtilis glutamine synthetase that block its interaction with transcription factor TnrA. Mol Microbiol 45:627–635
    [Google Scholar]
  16. Forchhammer K., Tandeau de Marsac N. 1994; The PII protein in the cyanobacterium Synechococcus sp. strain PCC 7942 is modified by serine phosphorylation and signals the cellular N-status. J Bacteriol 176:84–91
    [Google Scholar]
  17. Hu P., Leighton T., Ishkanova G., Kustu S. 1999; Sensing of nitrogen limitation by Bacillus subtilis: comparison to enteric bacteria. J Bacteriol 181:5042–5050
    [Google Scholar]
  18. Jakoby M., Krämer R., Burkovski A. 1999; Nitrogen regulation in Corynebacterium glutamicum: isolation of genes involved and biochemical characterization of corresponding proteins. FEMS Microbiol Lett 173:303–310
    [Google Scholar]
  19. Jakoby M., Nolden L., Meier-Wagner J., Krämer R., Burkovski A. 2000; AmtR, a global repressor in the nitrogen regulation system of Corynebacterium glutamicum. Mol Microbiol 37:964–977
    [Google Scholar]
  20. Kleiner D. 1985; Bacterial ammonium transport. FEMS Microbiol Rev 32:87–100
    [Google Scholar]
  21. Kunst F., Rapoport G. 1995; Salt stress is an environmental signal affecting degradative enzyme synthesis in Bacillus subtilis. J Bacteriol 177:2403–2407
    [Google Scholar]
  22. Ludwig H., Rebhan N., Blencke H.-M., Merzbacher M., Stülke J. 2002; Control of the glycolytic gapA operon by the catabolite control protein A in Bacillus subtilis: a novel mechanism of CcpA-mediated regulation. Mol Microbiol 45:543–553
    [Google Scholar]
  23. Meier-Wagner J., Nolden L., Jakoby M., Siewe R., Krämer R., Burkovski A. 2001; Multiplicity of ammonium uptake systems in Corynebacterium glutamicum: role of Amt and AmtB. Microbiology 147:135–143
    [Google Scholar]
  24. Meinken C., Blencke H.-M., Ludwig H., Stülke J. 2003; Expression of the glycolytic gapA operon in Bacillus subtilis: differential syntheses of proteins encoded by the operon. Microbiology 149:751–761
    [Google Scholar]
  25. Merrick M., Edwards R. A. 1995; Nitrogen control in bacteria. Microbiol Rev 59:604–622
    [Google Scholar]
  26. Ninfa A. J., Atkinson M. R. 2000; PII signal transduction proteins. Trends Microbiol 8:172–179
    [Google Scholar]
  27. Primrose S. B., Ehrlich S. D. 1981; Isolation of plasmid deletion mutants and study of their instability. Plasmid 6:193–201
    [Google Scholar]
  28. Sambrook J., Fritsch E. F., Maniatis T. 1989 Molecular Cloning: a Laboratory Manual, 2nd edn. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  29. Saxild H. H., Nygaard P. 1987; Genetic and physiological characterization of Bacillus subtilis mutants resistant to purine analogs. J Bacteriol 169:2977–2983
    [Google Scholar]
  30. Schmalisch M., Langbein I., Stülke J. 2002; The general stress protein Ctc of Bacillus subtilis is a ribosomal protein. J Mol Microbiol Biotechnol 4:495–501
    [Google Scholar]
  31. Schreier H. J., Brown S. W., Hirschi K. D., Nomellini J. F., Sonenshein A. L. 1989; Regulation of Bacillus subtilis glutamine synthetase gene expression by the product of the glnR gene. J Mol Biol 210:51–63
    [Google Scholar]
  32. Siewe R. M., Weil B., Burkovski A., Eikmanns B. J., Eikmanns M., Krämer R. 1996; Functional and genetic characterization of the (methyl)ammonium uptake carrier of Corynebacterium glutamicum. J Biol Chem 271:5398–5403
    [Google Scholar]
  33. Soupene E., He L., Yan D., Kustu S. 1998; Ammonia acquisition in enteric bacteria: physiological role of the ammonium/methylammonium transport B (AmtB) protein. Proc Natl Acad Sci U S A 95:7030–7034
    [Google Scholar]
  34. Thomas G. H., Mullins J. G. L., Merrick M. 2000a; Membrane topology of the Mep/Amt family of ammonium transporters. Mol Microbiol 37:331–344
    [Google Scholar]
  35. Thomas G. H., Coutts G., Merrick M. 2000b; The glnK amtB operon: a conserved gene pair in prokaryotes. Trends Genet 16:11–14
    [Google Scholar]
  36. van Dommelen A., Keijers V., Vanderleyden J., de Zamaroczy M. 1998; (Methyl)ammonium transport in the nitrogen-fixing bacterium Azospirillum brasilense. J Bacteriol 180:2652–2659
    [Google Scholar]
  37. Wacker I., Ludwig H., Reif I., Blencke H.-M., Detsch C., Stülke J. 2003; The regulatory link between carbon and nitrogen metabolism in Bacillus subtilis: regulation of the gltAB operon by the catabolite control protein CcpA. Microbiology 149:3001–3009
    [Google Scholar]
  38. Weinrauch Y., Msadek T., Kunst F., Dubnau D. 1991; Sequence and properties of comQ, a new competence regulatory gene of Bacillus subtilis. J Bacteriol 173:5685–5693
    [Google Scholar]
  39. Wray L. V. Jr, Atkinson M. R., Fisher S. H. 1991; Identification and cloning of the glnR locus, which is required for transcription of the glnA gene in Streptomyces coelicolor A3(2. J Bacteriol 173:7351–7360
    [Google Scholar]
  40. Wray L. V. Jr, Atkinson M. R., Fisher S. H. 1994; The nitrogen-regulated Bacillus subtilis nrgAB operon encodes a membrane protein and a protein highly similar to the Escherichia coli glnB-encoded PII protein. J Bacteriol 176:108–114
    [Google Scholar]
  41. Wray L. V. Jr, Ferson A. E., Rohrer K., Fisher S. H. 1996; TnrA, a transcription factor required for global nitrogen regulation in Bacillus subtilis. Proc Natl Acad Sci U S A 93:8841–8845
    [Google Scholar]
  42. Wray L. V. Jr, Zalieckas J. M., Fisher S. H. 2001; Bacillus subtilis glutamine synthetase controls gene expression through a protein–protein interaction with transcription factor TnrA. Cell 107:427–435
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.26512-0
Loading
/content/journal/micro/10.1099/mic.0.26512-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error