1887

Abstract

The regulon protects cells against superoxide and nitric oxide. Oxidation of the SoxR sensor, a [2Fe–2S]-containing transcriptional regulator, triggers the response, but the nature of the cellular signal sensed by SoxR is still a matter of debate. , the sensor is maintained in a reduced, inactive state by the activities of SoxR reductases, which employ NADPH as an electron donor. The hypothesis that NADPH levels affect deployment of the response was tested by transforming cells with genes encoding enzymes and proteins that lead to either build-up or depletion of the cellular NADPH pool. Introduction of NADP-reducing enzymes, such as wheat non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase or malic enzyme, led to NADPH accumulation, inhibition of the regulon and enhanced sensitivity to the superoxide propagator methyl viologen (MV). Conversely, expression of pea ferredoxin (Fd), a redox shuttle that can oxidize NADPH via ferredoxin-NADP(H) reductase, resulted in execution of the response in the absence of oxidative stress, and in higher tolerance to MV. Processes that caused NADPH decline, including oxidative stress and Fd activity, correlated with an increase in total (NADP+NADPH) stocks. SoxS expression can be induced by Fd expression or by MV in anaerobiosis, under conditions in which NADPH is oxidized but no superoxide can be formed. The results indicate that activation of the regulon in cells exposed to superoxide-propagating compounds can be triggered by depletion of the NADPH stock rather than accumulation of superoxide itself. They also suggest that bacteria need to finely regulate homeostasis of the NADP(H) pool to enable proper deployment of this defensive response.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.039461-0
2011-04-01
2024-03-28
Loading full text...

Full text loading...

/deliver/fulltext/micro/157/4/957.html?itemId=/content/journal/micro/10.1099/mic.0.039461-0&mimeType=html&fmt=ahah

References

  1. Andersen K. B., von Meyenburg K. 1977; Charges of nicotinamide adenine nucleotides and adenylate energy charge as regulatory parameters of the metabolism in Escherichia coli . J Biol Chem 252:4151–4156
    [Google Scholar]
  2. Apel K., Hirt H. 2004; Reactive oxygen species: metabolism, oxidative stress, and signal transduction. Annu Rev Plant Biol 55:373–399
    [Google Scholar]
  3. Blanchard J. L., Wholey W. Y., Conlon E. M., Pomposiello P. J. 2007; Rapid changes in gene expression dynamics in response to superoxide reveal soxRS -dependent and independent transcriptional networks. PLoS ONE 2:e1186
    [Google Scholar]
  4. Bologna F. P., Andreo C. S., Drincovich M. F. 2007; Escherichia coli malic enzymes: two isoforms with substantial differences in kinetic properties, metabolic regulation, and structure. J Bacteriol 189:5937–5946
    [Google Scholar]
  5. Brumaghim J. L., Li Y., Henle E., Linn S. 2003; Effects of hydrogen peroxide upon nicotinamide nucleotide metabolism in Escherichia coli : changes in enzyme levels and nicotinamide nucleotide pools and studies of the oxidation of NAD(P)H by Fe(III. J Biol Chem 278:42495–42504
    [Google Scholar]
  6. Bustos D. M., Iglesias A. A. 2002; Non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase is post-translationally phosphorylated in heterotrophic cells of wheat ( Triticum aestivum . FEBS Lett 530:169–173
    [Google Scholar]
  7. Carrillo N., Ceccarelli E. A. 2003; Open questions in ferredoxin-NADP+ reductase catalytic mechanism. Eur J Biochem 270:1900–1915
    [Google Scholar]
  8. Catalano Dupuy D. L., Rial D. V., Ceccarelli E. A. 2004; Inhibition of pea ferredoxin-NADP(H) reductase by Zn-ferrocyanide. Eur J Biochem 271:4582–4593
    [Google Scholar]
  9. Dietrich L. E. P., Price-Whelan A., Petersen A., Whiteley M., Newman D. K. 2006; The phenazine pyocyanin is a terminal signalling factor in the quorum sensing network of Pseudomonas aeruginosa . Mol Microbiol 61:1308–1321
    [Google Scholar]
  10. Ding H., Hidalgo E., Demple B. 1996; The redox state of the [2Fe–2S] clusters in SoxR protein regulates its activity as a transcription factor. J Biol Chem 271:33173–33175
    [Google Scholar]
  11. Fuhrer T., Sauer U. 2009; Different biochemical mechanisms ensure network-wide balancing of reducing equivalents in microbial metabolism. J Bacteriol 191:2112–2121
    [Google Scholar]
  12. Gaudu P., Fontecave M. 1994; The NADPH : sulfite reductase of Escherichia coli is a paraquat reductase. Eur J Biochem 226:459–463
    [Google Scholar]
  13. Gaudu P., Dubrac S., Touati D. 2000; Activation of SoxR by overproduction of desulfoferrodoxin: multiple ways to induce the soxRS regulon. J Bacteriol 182:1761–1763
    [Google Scholar]
  14. Giró M., Carrillo N., Krapp A. R. 2006; Glucose-6-phosphate dehydrogenase and ferredoxin-NADP(H) reductase contribute to damage repair during the soxRS response of Escherichia coli . Microbiology 152:1119–1128
    [Google Scholar]
  15. Gorodetsky A. A., Dietrich L. E., Lee P. E., Demple B., Newman D. K., Barton J. K. 2008; DNA binding shifts the redox potential of the transcription factor SoxR. Proc Natl Acad Sci U S A 105:3684–3689
    [Google Scholar]
  16. Grose J. H., Joss L., Velick S. F., Roth J. R. 2006; Evidence that feedback inhibition of NAD kinase controls responses to oxidative stress. Proc Natl Acad Sci U S A 103:7601–7606
    [Google Scholar]
  17. Iddar A., Valverde F., Assobhei O., Serrano A., Soukri A. 2005; Widespread occurrence of non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase among Gram-positive bacteria. Int Microbiol 8:251–258
    [Google Scholar]
  18. Imlay J. A. 2008; Cellular defenses against superoxide and hydrogen peroxide. Annu Rev Biochem 77:755–776
    [Google Scholar]
  19. Kobayashi K., Tagawa S. 1999; Isolation of reductase for SoxR that governs an oxidative response regulon from Escherichia coli . FEBS Lett 451:227–230
    [Google Scholar]
  20. Koo M. S., Lee J. H., Rah S. Y., Yeo W. S., Lee J. W., Lee K. L., Koh Y. S., Kang S. O., Roe J. H. 2003; A reducing system of the superoxide sensor SoxR in Escherichia coli . EMBO J 22:2614–2622
    [Google Scholar]
  21. Krapp A. R., Rodríguez R. E., Poli H. O., Paladini D. H., Palatnik J. F., Carrillo N. 2002; The flavoenzyme ferredoxin (flavodoxin)-NADP(H) reductase modulates NADP(H) homeostasis during the soxRS response of Escherichia coli . J Bacteriol 184:1474–1480
    [Google Scholar]
  22. Liochev S. I., Fridovich I. 1992; Fumarase C, the stable fumarase of Escherichia coli , is controlled by the soxRS regulon. Proc Natl Acad Sci U S A 89:5892–5896
    [Google Scholar]
  23. Liochev S. I., Hausladen A., Beyer W. F. Jr, Fridovich I. 1994; NADPH : ferredoxin oxidoreductase acts as a paraquat diaphorase and is a member of the soxRS regulon. Proc Natl Acad Sci U S A 91:1328–1331
    [Google Scholar]
  24. Manchado M., , Michán C., Pueyo C. 2000; Hydrogen peroxide activates the soxRS regulon in vivo. J Bacteriol 182:6842–6844
    [Google Scholar]
  25. Martínez E., Bartolomé B., de la Cruz F. 1988; pACYC184-derived cloning vectors containing the multiple cloning site and lacZα reporter gene of pUC8/9 and pUC18/19 plasmids. Gene 68:159–162
    [Google Scholar]
  26. Miller J. H. 1992 A Short Course in Bacterial Genetics: a Laboratory Manual for E. coli and Related Bacteria Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  27. Nunoshiba T., Hidalgo E., Amábile Cuevas C. F., Demple B. 1992; Two-stage control of an oxidative stress regulon: the Escherichia coli SoxR protein triggers redox-inducible expression of the soxS regulatory gene. J Bacteriol 174:6054–6060
    [Google Scholar]
  28. Nunoshiba T., deRojas-Walker T., Wishnok J. S., Tannenbaum S. R., Demple B. 1993; Activation by nitric oxide of an oxidative-stress response that defends Escherichia coli against activated macrophages. Proc Natl Acad Sci U S A 90:9993–9997
    [Google Scholar]
  29. Paterson E. S., Boucher S. E., Lambert I. B. 2002; Regulation of the nfsA gene in Escherichia coli by SoxS. J Bacteriol 184:51–58
    [Google Scholar]
  30. Pomposiello P. J., Bennik M. H., Demple B. 2001; Genome-wide transcriptional profiling of the Escherichia coli responses to superoxide stress and sodium salicylate. J Bacteriol 183:3890–3902
    [Google Scholar]
  31. Privalle C. T., Kong S. E., Fridovich I. 1993; Induction of manganese-containing superoxide dismutase in anaerobic Escherichia coli by diamide and 1,10-phenanthroline: sites of transcriptional regulation. Proc Natl Acad Sci U S A 90:2310–2314
    [Google Scholar]
  32. Sedmak J. J., Grossberg S. E. 1977; A rapid, sensitive, and versatile assay for protein using Coomassie brilliant blue G250. Anal Biochem 79:544–552
    [Google Scholar]
  33. Singh R., Mailloux R. J., Puiseux-Dao S., Appanna V. D. 2007; Oxidative stress evokes a metabolic adaptation that favors increased NADPH synthesis and decreased NADH production in Pseudomonas fluorescens . J Bacteriol 189:6665–6675
    [Google Scholar]
  34. Slater T. F., Sawyer B. 1962; A colorimetric method for estimating the pyridine nucleotide content of small amounts of animal tissue. Nature 193:454–456
    [Google Scholar]
  35. Watanabe S., Kita A., Kobayashi K., Miki K. 2008; Crystal structure of the [2Fe–2S] oxidative-stress sensor SoxR bound to DNA. Proc Natl Acad Sci U S A 105:4121–4126
    [Google Scholar]
  36. Woodmansee A. N., Imlay J. A. 2002; Reduced flavins promote oxidative DNA damage in non-respiring Escherichia coli by delivering electrons to intracellular free iron. J Biol Chem 277:34055–34066
    [Google Scholar]
  37. Wu J., Weiss B. 1992; Two-stage induction of the soxRS (superoxide response) regulon of Escherichia coli . J Bacteriol 174:3915–3920
    [Google Scholar]
  38. Zheng M., Doan B., Schneider T. D., Storz G. 1999; oxyR and soxRS regulation of fur . J Bacteriol 181:4639–4643
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.039461-0
Loading
/content/journal/micro/10.1099/mic.0.039461-0
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