1887

Abstract

possesses two distinct thioredoxin proteins (Trx1 and Trx2) which may play important roles in the ability of this bacterium to survive oxidative stress. Trx1 has previously been shown to be an electron donor for alkyl-hydroperoxide reductase (AhpC), one of three members of the peroxiredoxin family of antioxidant peroxidases present in . In this study, mutants in the and genes encoding Trx1 and Trx2, respectively, and in the and genes, which encode the remaining two members of the peroxiredoxin family, were constructed in order to determine their roles in resistance to damage by reactive oxygen and nitrogen species. Mutation of led to a pronounced increase in sensitivity to oxygen, hydrogen peroxide and the superoxide generator paraquat, as well as to the nitric oxide (NO) releasers sodium nitroprusside (SNP) and -nitrosoglutathione (GSNO), consistent with an role for Trx1 as a reductant for AhpC. A single mutant grew normally in an atmosphere of 2 % (v/v) O but grew very poorly in 10 % (v/v) O. It showed slight increases in killing by hydrogen peroxide, paraquat, SNP and GSNO compared to the wild-type, but was significantly more sensitive to cumene hydroperoxide in disc-diffusion assays. A double mutant was very sensitive to all of the oxidative and nitrosative stresses applied. Comparison of the phenotypes of the and mutants showed that Tpx plays a significant role in peroxide and superoxide resistance in , while the role of Bcp is minimal. No evidence was obtained for a role for either Tpx or Bcp in resistance to the toxic effects of NO. The results show that a functional thioredoxin system is necessary for both oxidative and nitrosative stress resistance in but, surprisingly, is not essential for viability despite the absence of glutathione and a glutaredoxin system in this bacterium.

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2003-01-01
2020-08-04
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References

  1. Akopyants N. S, Eaton K. A., Berg D. E. 1995; Adaptive mutation and co-colonization during infection of gnotobiotic piglets. Infect Immun63:116–121
    [Google Scholar]
  2. Alm R. A, Ling L.-S. L, Moir D. T.. 20 other authors 1999; Genomic sequencing comparison of two unrelated isolates of the human gastric pathogen Helicobacter pylori. Nature 397:176–180
    [Google Scholar]
  3. Andersen L. P., Wadström T. others 2001; Basic bacteriology and culture. In Helicobacter pylori: Physiology and Genetics pp27–52 Edited by Mobley H. L. T.. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  4. Baker L. M. S, Raudonikiene A, Hoffman P. S., Poole L. B. 2001; Essential thioredoxin-dependent peroxiredoxin system from Helicobacter pylori : genetic and kinetic characterization. J Bacteriol183:1961–1973
    [Google Scholar]
  5. Bryk R, Griffin P., Nathan C. 2000; Peroxynitrite reductase activity of bacterial peroxiredoxins. Nature407:211–215
    [Google Scholar]
  6. Costa Seaver L., Imlay J. A. 2001; Alkyl hydroperoxide reductase is the primary scavenger of endogenous hydrogen peroxide in Escherichia coli. J Bacteriol183:7173–7181
    [Google Scholar]
  7. Dixon M. F. others 2001; Pathology of gastritis and peptic ulceration. In Helicobacter pylori: Physiology and Genetics pp459–470 Edited by Mobley H. L. T.. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  8. Ferrero R. L, Cussac V, Courcoux P., Labigne-Roussel A. 1992; Construction of isogenic urease-negative mutants of Helicobacter pylori by allelic exchange. J Bacteriol174:4212–4217
    [Google Scholar]
  9. Forman D, Newell D. G, Fullerton F, Yarnell J. W. G, Stacey A. R, Wald N., Sitas F. 1991; Association between infection with Helicobacter pylori and risk of gastric cancer: evidence from a prospective investigation. Br Med J302:1302–1305
    [Google Scholar]
  10. Goodwin A, Kersulyte D, Sisson G, Veldhuyzen van Zanten S. J. O, Berg D. E., Hoffman P. S. 1998; Metronidazole resistance in Helicobacter pylori is due to null mutations in a gene ( rdxA ) that encodes an oxygen-insensitive NADPH nitroreductase. Mol Microbiol28:383–393
    [Google Scholar]
  11. Hughes M. N. 1999; Relationships between nitric oxide, nitroxyl ion, nitrosonium cation and peroxynitrite. Biochim Biophys Acta1411:263–272
    [Google Scholar]
  12. Hughes N. J, Chalk P. A, Clayton C. L., Kelly D. J. 1995; Identification of carboxylation enzymes and characterization of a novel four-subunit pyruvate : flavodoxin oxidoreductase from Helicobacter pylori. J Bacteriol177:3953–3959
    [Google Scholar]
  13. Hughes N. J, Clayton C. L, Chalk P. A., Kelly D. J. 1998; Helicobacter pylori porCDAB and oorDABC genes encode distinct pyruvate : flavodoxin and 2-oxoglutarateacceptor oxidoreductases which mediate electron transport to NADP. J Bacteriol180:1119–1128
    [Google Scholar]
  14. Jeong W, Cha M.-K., Kim I.-H. 2000; Thioredoxin dependent hydroperoxidase activity of bacterioferritin comigratory protein (BCP) as a new member of the thiol-specific antioxidant protein (TSA)/alkyl hydroperoxide peroxidase C (AhpC) family. J Biol Chem275:2924–2930
    [Google Scholar]
  15. Jordan A., Reichard P. 1998; Ribonucleotide reductases. Annu Rev Biochem67:71–98
    [Google Scholar]
  16. Jungblut P. R, Bumann D, Haas G, Zimny-Arndt U, Holland P, Lamer S, Siejak F, Aebischer A., Meyer T. F. 2000; Comparative proteome analysis of Helicobacter pylori. Mol Microbiol36:710–725
    [Google Scholar]
  17. Kelly D. J. 1998; The physiology and metabolism of the human gastric pathogen Helicobacter pylori. Adv Microb Phys40:137–189
    [Google Scholar]
  18. Lundstrom A. M., Bolin I. 2000; A 26 kDa protein of Helicobacter pylori shows alkyl hydroperoxide reductase (AhpC) activity and the mono-cistronic transcription of the gene is affected by pH. Microb Pathog29:257–266
    [Google Scholar]
  19. Marmur J. 1961; A procedure for the isolation of deoxyribonucleic acid from microorganisms. J Mol Biol3:208–218
    [Google Scholar]
  20. Nagata K, Yu H, Nishikawa M, Kashiba M, Nakamura A, Sato E. F, Tamura T., Inouye M. 1998; Helicobacter pylori generates superoxide radicals and modulates nitric oxide metabolism. J Biol Chem273:14071–14073
    [Google Scholar]
  21. Olczak A. A, Olson J. W., Maier R. J. 2002; Oxidative stress resistance mutants of Helicobacter pylori. J Bacteriol184:3186–3193
    [Google Scholar]
  22. Pittman M. S, Goodwin M., Kelly D. J. 2001; Chemotaxis in the human gastric pathogen Helicobacter pylori : different roles for CheW and the three CheV paralogues, and evidence for CheV2 phosphorylation. Microbiology147:2493–2504
    [Google Scholar]
  23. Ritz D., Beckwith J. 2001; Roles of thiol-redox pathways in bacteria. Annu Rev Microbiol55:21–48
    [Google Scholar]
  24. Schröder E., Ponting C. P. 1998; Evidence that peroxiredoxins are novel members of the thioredoxin fold superfamily. Protein Sci7:2465–2468
    [Google Scholar]
  25. Sellars M. J, Hall S. J., Kelly D. J. 2002; Growth of Campylobacter jejuni supported by respiration of fumarate, nitrate, nitrite, trimethylamine- N -oxide or dimethylsulphoxide requires oxygen. J Bacteriol184:4187–4196
    [Google Scholar]
  26. Storz G., Zheng M. 2000; Oxidative stress. In Bacterial Stress Responses pp47–60 Edited by Storz G., Hengge-Aronis R.. Washington, DC: American Society for Microbiology;
    [Google Scholar]
  27. Tomb J.-F, White O, Kerlavage A. R.. 39 other authors 1997; The complete genome sequence of the gastric pathogen Helicobacter pylori. Nature 388:539–547
    [Google Scholar]
  28. Wan X.-Y, Zhou Y, Yan Z.-Y, Wang H.-L, Hu Y.-D., Jin D.-Y. 1997; Scavengase p20: a novel family of bacterial antioxidant enzymes. FEBS Lett407:32–36
    [Google Scholar]
  29. Wang Y., Taylor D. E. 1990; Chloramphenicol resistance in Campylobacter coli – nucleotide-sequence, expression, and cloning vector construction. Gene94:23–28
    [Google Scholar]
  30. Windle H. J, Fox A, Ni Eidhin D., Kelleher D. 2000; The thioredoxin system of Helicobacter pylori. J Biol Chem275:5081–5089
    [Google Scholar]
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