1887

Abstract

The concentration of glucose in the medium influences the regulation of cAMP levels in Growth in minimal medium with micromolar glucose results in 8- to 10-fold higher intracellular cAMP concentrations than observed during growth with excess glucose. Current models would suggest that the difference in cAMP levels between glucose-rich and glucose-limited states is due to altered transport flux through the phosphoenolpyruvate : glucose phosphotransferase system (PTS), which in turn controls adenylate cyclase. A consequence of this model is that cAMP levels should be inversely related to the saturation of the PTS transporter. To test this hypothesis, the relationship between external glucose concentration and cAMP levels inside were investigated in detail, both through direct cAMP assay and indirectly through measurement of expression of cAMP-regulated genes. Responses were followed in batch, dialysis and glucose-limited continuous culture. A sharp rise in intracellular cAMP occurred when the nutrient concentration in minimal medium dropped to approximately 0∙3 mM glucose. Likewise, addition of >0∙3 mM glucose, but not <0∙3 mM glucose, sharply reduced the intracellular cAMP level of starving bacteria. There was no striking shift in growth rate or [C]glucose assimilation in bacteria passing through the 0∙5 to 0∙3 mM concentration threshold influencing cAMP levels, suggesting that neither metabolic flux nor transporter saturation influenced the sensing of nutrient levels. The (IIA/IIBC) PTS is 96–97% saturated at 0∙3 mM glucose so these results are not easily reconcilable with current models of cAMP regulation. Aside from the transition in cAMP levels initiated above 0∙3 mM, a second shift occurred below 1 μM glucose. Approaching starvation, well below saturation of the PTS, cAMP levels either increased or decreased depending on unknown factors that differ between common K-12 strains.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-143-6-1909
1997-06-01
2021-11-30
Loading full text...

Full text loading...

/deliver/fulltext/micro/143/6/mic-143-6-1909.html?itemId=/content/journal/micro/10.1099/00221287-143-6-1909&mimeType=html&fmt=ahah

References

  1. Benner-Luger D., Boos W. 1988; The mglB sequence of Salmonella typhimurium LT2; promoter analysis by gene fusions and evidence for a divergently oriented gene coding for the mgl repressor.. Mol Gen Genet 214:579–587
    [Google Scholar]
  2. Bohannon D. E., Connell N., Keener J., Tormo A., Espinosa-Urgel M., Zambrano M. M., Kolter R. 1991; Stationary-phase-inducible ‘gearbox’ promoters: differential effects of katF mutations and role of sigma 70.. J Bacteriol 173:4482–4492
    [Google Scholar]
  3. Botsford J. L., Harman J. G. 1992; Cyclic AMP in prokaryotes.. Microbiol Rev 56:100–122
    [Google Scholar]
  4. Casabadan M. J. 1976; Transposition and fusion of the lac operon to selected promoters in E. coli using bacteriophage Lambda and Mu.. J Mol Biol 104:541–555
    [Google Scholar]
  5. Death A., Ferenci T. 1993; The importance of the binding-protein-dependent Mgl system to the transport of glucose in Escherichia coli growing on low sugar concentrations.. Res Microbiol 144:529–537
    [Google Scholar]
  6. Death A., Ferenci T. 1994; Between feast and famine: endogenous inducer synthesis in the adaptation of Escherichia coli to growth with limiting carbohydrates.. J Bacteriol 176:5101–5107
    [Google Scholar]
  7. Death A., Notley L., Ferenci T. 1993; Derepression of LamB protein facilitates outer membrane permeation of carbohydrates into Escherichia coli under conditions of nutrient stress.. J Bacteriol 175:1475–1483
    [Google Scholar]
  8. Dumay V., Danchin A., Crasnier M. 1996; Regulation of Escherichia coli adenylate cyclase activity during hexose phosphate transport.. Microbiology 142:575–583
    [Google Scholar]
  9. Epstein W., Rothman-Denes L. B., Hesse J. 1975; Adenosine 3ʹ : 5ʹ-cyclic monophosphate as mediator of catabolite repression in Escherichia coli.. Proc Natl Acad Sci USA 72:2300–2304
    [Google Scholar]
  10. Ferenci T. 1996; Adaptation to life at micromolar nutrient levels: the regulation of Escherichia coli glucose transport by endoinduction and cAMP.. FEMS Microbiol Rev 18:301–317
    [Google Scholar]
  11. Hernandez V. J., Bremer H. 1991; E. coli ppGpp synthetase II activity requires spoT.. J Biol Chem 266:5991–5999
    [Google Scholar]
  12. Hunter I. S., Kornberg H. L. 1979; Glucose transport of Escherichia coli growing in glucose-limited continuous culture.. Biochem J 178:97–101
    [Google Scholar]
  13. Joseph E., Bernsley C., Guiso N., Ullmann A. 1982; Multiple regulation of the activity of adenylate cyclase in Escherichia coli.. Mol Gen Genet 185:262–268
    [Google Scholar]
  14. Kaasen I., Falkenberg P., Styrvold O. B., Strom A. R. 1992; Molecular cloning and physical mapping of the otsBA genes, which encode the osmoregulatory trehalose pathway of Escherichia coli : evidence that transcription is activated by katF (appR).. J Bacterial 174:889–898
    [Google Scholar]
  15. Koch A. L. 1979; Microbial growth in low concentrations of nutrients. In Strategies of Microbial Life in Extreme Environments, pp.. 261–279 Edited by M. Shilo. Weinheim: Verlag Chemie..
    [Google Scholar]
  16. Kolb A., Busby S., Buc H., Garges S., Adhya S. 1993; Transcriptional regulation by cAMP and its receptor protein.. Annu Rev Biochem 62:749–795
    [Google Scholar]
  17. Levy S., Zeng G. Q., Danchin A. 1990; Cyclic AMP synthesis in Escherichia coli strains bearing known deletions in the pts phosphotransferase operon.. Gene 86:27–33
    [Google Scholar]
  18. Makman R. S., Sutherland E. W. 1965; Adenosine 3ʹ, 5ʹ-phosphate in Escherichia coli.. J Biol Chem 240:1309–1314
    [Google Scholar]
  19. Matin A., Matin M. K. 1982; Cellular levels, excretion and synthesis rates of cAMP in Escherichia coli grown in continuous culture.. J Bacteriol 149:801–817
    [Google Scholar]
  20. Miller J. 1972; Experiments in Molecular Genetics. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory..
    [Google Scholar]
  21. Notley L., Ferenci T. 1995; Differential expression of mal genes under cAMP and endogenous inducer control in nutrient stressed Escherichia coli.. Mol Microbiol 16:121–129
    [Google Scholar]
  22. Notley L., Ferenci T. 1996; Induction of RpoS-dependent functions in glucose-limited continuous culture: what level of nutrient limitation induces the stationary phase of Escherichia coli?. J Bacteriol 178:1465–1468
    [Google Scholar]
  23. Perlman R. L., De Crombrugghe B., Pastan I. 1969; Cyclic AMP regulates catabolite and transient repression in E. coli.. Nature 223:810–812
    [Google Scholar]
  24. Peterkofsky A., Gazdar C. 1975; Interaction of enzyme I of the phosphoenolpyruvate : sugar phosphotransferase system with adenylate cyclase of Escherichia coli.. Proc Natl Acad Sci USA 72:2920–2924
    [Google Scholar]
  25. Peterkofsky A., Reizer A., Reizer J., Gollop N., Zhu P. P., Amin N. 1993; Bacterial adenylyl cyclases.. Prog Nucleic Acid Res Mol Biol 44:31–65
    [Google Scholar]
  26. Postma P. W., Ruijter G. J. G., van der Vlag J., van Dam K. 1992; Control of carbohydrate metabolism in enteric bacteria: qualitative and quantitative aspects. In Molecular Mechanisms of Transport, pp.. 97–105 Edited by E. Quagliarello & F. Palmieri. Amsterdam: Elsevier..
    [Google Scholar]
  27. Postma P. W., Lengeler J. W., Jacobson G. R. 1993; Phosphoenolpyruvate: carbohydrate phosphotransferase systems of bacteria.. Microbiol Rev 57:543–594
    [Google Scholar]
  28. Postma P. W., Lengeler J. W., Jacobson G. R. 1996; Phosphoenolpyruvate : carbohydrate phosphotransferase systems. In Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, pp.. 1149–1174 Edited by F. C. Neidhardt and others. Washington, DC: American Society for Microbiology..
    [Google Scholar]
  29. Roy A., Glaser P., Danchin A. 1988; Aspects of the regulation of adenylate cyclase synthesis in Escherichia coli K12.. J Gen Microbiol 134:359–367
    [Google Scholar]
  30. Saier M. H., Jr. 1989; Protein phosphorylation and allosteric control of inducer exclusion and catabolite repression by the bacterial phosphoenolpyruvate : sugar phosphotransferase system.. Microbiol Rev 53:109–120
    [Google Scholar]
  31. Saier M. H., Jr, Feucht B. U. 1975; Coordinate regulation of adenylate cyclase and carbohydrate permeases by the phosphoenolpyruvate : sugar phosphotransferase system in Salmonella typhimurium.. J Biol Chem 250:7078–7080
    [Google Scholar]
  32. Saier M. H., Jr, Feucht B. U., McCaman M. T. 1975; Regulation of intracellular adenosine cyclic 3' :5'-monophosphate levels in Escherichia coli and Salmonella typhimurium. Evidence for energy-dependent excretion of the cyclic nucleotide.. J Biol Chem 250:7593–7601
    [Google Scholar]
  33. Saier M. H., Jr, Ramseier T. M., Reizer J. 1996; Regulation of carbon utilisation. In Escherichia coli and Salmonella: Cellular and Molecular Biology, 2nd edn, pp.. 1325–1343 Edited by F. C. Neidhardt and others. Washington, DC: American Society for Microbiology..
    [Google Scholar]
  34. Schultz J. E., Latter G. I., Matin A. 1988; Differential regulation by cyclic AMP of starvation protein synthesis in Escherichia coli.. J Bacteriol 170:3903–3909
    [Google Scholar]
  35. Schwartz M. 1987; The maltose regulon. In Escherichia coli and Salmonella: Cellular and Molecular Biology, pp.. 1482–1502 Edited by F. C. Neidhardt and others. Washington, DC: American Society for Microbiology..
    [Google Scholar]
  36. Senn H., Lendenmann U., Snozzi M., Hamer G., Egli T. 1994; The growth of Escherichia coli in glucose-limited chemostat cultures: a re-examination of the kinetics.. Biochim Biophys Acta 1201:424–436
    [Google Scholar]
  37. Tchetina E., Newman E. B. 1995; Identification of lrp-regulated genes by inverse PCR and sequencing – regulation of two mal operons of Escherichia coli by leucine-responsive regulatory protein.. J Bacteriol 177:2679–2683
    [Google Scholar]
  38. Ullmann A., Danchin A. 1983; Role of cyclic AMP in bacteria.. Adv Cyclic Nucleotide Res 15:1–53
    [Google Scholar]
  39. Wright L. F., Milne D., Knowles C. J. 1979; The regulatory effects of growth rate and cAMP levels on carbon catabolism and respiration in Escherichia coli K-12.. Biochim Biophys Acta 539:73–80
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-143-6-1909
Loading
/content/journal/micro/10.1099/00221287-143-6-1909
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

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