Skip to main content
PMC home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1997 Aug;179(16):5188–5194. doi: 10.1128/jb.179.16.5188-5194.1997

Protection of DNA during oxidative stress by the nonspecific DNA-binding protein Dps.

A Martinez 1, R Kolter 1
PMCID: PMC179379  PMID: 9260963

Abstract

Reactive oxygen species can damage most cellular components, but DNA appears to be the most sensitive target of these agents. Here we present the first evidence of DNA protection against the toxic and mutagenic effects of oxidative damage in metabolically active cells: direct protection of DNA by Dps, an inducible nonspecific DNA-binding protein from Escherichia coli. We demonstrate that in a recA-deficient strain, expression of Dps from an inducible promoter prior to hydrogen peroxide challenge increases survival and reduces the number of chromosomal single-strand breaks. dps mutants exhibit increased levels of the G x C-->T x A mutations characteristic of oxidative damage after treatment with hydrogen peroxide. In addition, expression of Dps from the inducible plasmid reduces the frequency of spontaneous G x C-->T x A and A x T-->T x A mutations and can partially suppress the mutator phenotype of mutM (fpg) and mutY alleles. In a purified in vitro system, Dps reduces the number of DNA single-strand breaks and Fpg-sensitive sites introduced by hydrogen peroxide treatment, indicating that the protection observed in vivo is a direct effect of DNA binding by Dps. The widespread conservation of Dps homologs among prokaryotes suggests that this may be a general strategy for coping with oxidative stress.

Full Text

The Full Text of this article is available as a PDF (2.0 MB).

Selected References

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

  1. Almirón M., Link A. J., Furlong D., Kolter R. A novel DNA-binding protein with regulatory and protective roles in starved Escherichia coli. Genes Dev. 1992 Dec;6(12B):2646–2654. doi: 10.1101/gad.6.12b.2646. [DOI] [PubMed] [Google Scholar]
  2. Altuvia S., Almirón M., Huisman G., Kolter R., Storz G. The dps promoter is activated by OxyR during growth and by IHF and sigma S in stationary phase. Mol Microbiol. 1994 Jul;13(2):265–272. doi: 10.1111/j.1365-2958.1994.tb00421.x. [DOI] [PubMed] [Google Scholar]
  3. Ames B. N. Understanding the causes of aging and cancer. Microbiologia. 1995 Sep;11(3):305–308. [PubMed] [Google Scholar]
  4. Ananthaswamy H. N., Eisenstark A. Repair of hydrogen peroxide-induced single-strand breaks in Escherichia coli deoxyribonucleic acid. J Bacteriol. 1977 Apr;130(1):187–191. doi: 10.1128/jb.130.1.187-191.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Asad N. R., Leitão A. C. Effects of metal ion chelators on DNA strand breaks and inactivation produced by hydrogen peroxide in Escherichia coli: detection of iron-independent lesions. J Bacteriol. 1991 Apr;173(8):2562–2568. doi: 10.1128/jb.173.8.2562-2568.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chen L., Helmann J. D. Bacillus subtilis MrgA is a Dps(PexB) homologue: evidence for metalloregulation of an oxidative-stress gene. Mol Microbiol. 1995 Oct;18(2):295–300. doi: 10.1111/j.1365-2958.1995.mmi_18020295.x. [DOI] [PubMed] [Google Scholar]
  7. Cupples C. G., Miller J. H. A set of lacZ mutations in Escherichia coli that allow rapid detection of each of the six base substitutions. Proc Natl Acad Sci U S A. 1989 Jul;86(14):5345–5349. doi: 10.1073/pnas.86.14.5345. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Czeczot H., Tudek B., Lambert B., Laval J., Boiteux S. Escherichia coli Fpg protein and UvrABC endonuclease repair DNA damage induced by methylene blue plus visible light in vivo and in vitro. J Bacteriol. 1991 Jun;173(11):3419–3424. doi: 10.1128/jb.173.11.3419-3424.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Demple B., Harrison L. Repair of oxidative damage to DNA: enzymology and biology. Annu Rev Biochem. 1994;63:915–948. doi: 10.1146/annurev.bi.63.070194.004411. [DOI] [PubMed] [Google Scholar]
  10. Farr S. B., Kogoma T. Oxidative stress responses in Escherichia coli and Salmonella typhimurium. Microbiol Rev. 1991 Dec;55(4):561–585. doi: 10.1128/mr.55.4.561-585.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Guzman L. M., Belin D., Carson M. J., Beckwith J. Tight regulation, modulation, and high-level expression by vectors containing the arabinose PBAD promoter. J Bacteriol. 1995 Jul;177(14):4121–4130. doi: 10.1128/jb.177.14.4121-4130.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Imlay J. A., Chin S. M., Linn S. Toxic DNA damage by hydrogen peroxide through the Fenton reaction in vivo and in vitro. Science. 1988 Apr 29;240(4852):640–642. doi: 10.1126/science.2834821. [DOI] [PubMed] [Google Scholar]
  13. Imlay J. A., Linn S. Bimodal pattern of killing of DNA-repair-defective or anoxically grown Escherichia coli by hydrogen peroxide. J Bacteriol. 1986 May;166(2):519–527. doi: 10.1128/jb.166.2.519-527.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Imlay J. A., Linn S. DNA damage and oxygen radical toxicity. Science. 1988 Jun 3;240(4857):1302–1309. doi: 10.1126/science.3287616. [DOI] [PubMed] [Google Scholar]
  15. Kato T., Watanabe M., Ohta T. Induction of the SOS response and mutations by reactive oxygen-generating compounds in various Escherichia coli mutants defective in the mutM, mutY or soxRS loci. Mutagenesis. 1994 May;9(3):245–251. doi: 10.1093/mutage/9.3.245. [DOI] [PubMed] [Google Scholar]
  16. Kuhnlein U., Penhoet E. E., Linn S. An altered apurinic DNA endonuclease activity in group A and group D xeroderma pigmentosum fibroblasts. Proc Natl Acad Sci U S A. 1976 Apr;73(4):1169–1173. doi: 10.1073/pnas.73.4.1169. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Levin D. E., Ames B. N. Classifying mutagens as to their specificity in causing the six possible transitions and transversions: a simple analysis using the Salmonella mutagenicity assay. Environ Mutagen. 1986;8(1):9–28. doi: 10.1002/em.2860080103. [DOI] [PubMed] [Google Scholar]
  18. Ley R. D. Postreplication repair in an excision-defective mutant of Escherichia coli: ultraviolet light-induced incorporation of bromodeoxyuridine into parental DNA. Photochem Photobiol. 1973 Aug;18(2):87–95. doi: 10.1111/j.1751-1097.1973.tb06397.x. [DOI] [PubMed] [Google Scholar]
  19. Ljungman M., Hanawalt P. C. Efficient protection against oxidative DNA damage in chromatin. Mol Carcinog. 1992;5(4):264–269. doi: 10.1002/mc.2940050406. [DOI] [PubMed] [Google Scholar]
  20. Lomovskaya O. L., Kidwell J. P., Matin A. Characterization of the sigma 38-dependent expression of a core Escherichia coli starvation gene, pexB. J Bacteriol. 1994 Jul;176(13):3928–3935. doi: 10.1128/jb.176.13.3928-3935.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Luo Y., Han Z., Chin S. M., Linn S. Three chemically distinct types of oxidants formed by iron-mediated Fenton reactions in the presence of DNA. Proc Natl Acad Sci U S A. 1994 Dec 20;91(26):12438–12442. doi: 10.1073/pnas.91.26.12438. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. McGrath R. A., Williams R. W. Reconstruction in vivo of irradiated Escherichia coli deoxyribonucleic acid; the rejoining of broken pieces. Nature. 1966 Oct 29;212(5061):534–535. doi: 10.1038/212534a0. [DOI] [PubMed] [Google Scholar]
  23. Michaels M. L., Miller J. H. The GO system protects organisms from the mutagenic effect of the spontaneous lesion 8-hydroxyguanine (7,8-dihydro-8-oxoguanine). J Bacteriol. 1992 Oct;174(20):6321–6325. doi: 10.1128/jb.174.20.6321-6325.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Nghiem Y., Cabrera M., Cupples C. G., Miller J. H. The mutY gene: a mutator locus in Escherichia coli that generates G.C----T.A transversions. Proc Natl Acad Sci U S A. 1988 Apr;85(8):2709–2713. doi: 10.1073/pnas.85.8.2709. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Peña M. M., Bullerjahn G. S. The DpsA protein of Synechococcus sp. Strain PCC7942 is a DNA-binding hemoprotein. Linkage of the Dps and bacterioferritin protein families. J Biol Chem. 1995 Sep 22;270(38):22478–22482. doi: 10.1074/jbc.270.38.22478. [DOI] [PubMed] [Google Scholar]
  26. STACEY K. A., SIMSON E. IMPROVED METHOD FOR THE ISOLATION OF THYMINE-REQUIRING MUTANTS OF ESCHERICHIA COLI. J Bacteriol. 1965 Aug;90:554–555. doi: 10.1128/jb.90.2.554-555.1965. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Sanchez-Salas J. L., Santiago-Lara M. L., Setlow B., Sussman M. D., Setlow P. Properties of Bacillus megaterium and Bacillus subtilis mutants which lack the protease that degrades small, acid-soluble proteins during spore germination. J Bacteriol. 1992 Feb;174(3):807–814. doi: 10.1128/jb.174.3.807-814.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Setlow B., Hand A. R., Setlow P. Synthesis of a Bacillus subtilis small, acid-soluble spore protein in Escherichia coli causes cell DNA to assume some characteristics of spore DNA. J Bacteriol. 1991 Mar;173(5):1642–1653. doi: 10.1128/jb.173.5.1642-1653.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Setlow P. Mechanisms for the prevention of damage to DNA in spores of Bacillus species. Annu Rev Microbiol. 1995;49:29–54. doi: 10.1146/annurev.mi.49.100195.000333. [DOI] [PubMed] [Google Scholar]
  30. Toyokuni S., Sagripanti J. L. Iron-mediated DNA damage: sensitive detection of DNA strand breakage catalyzed by iron. J Inorg Biochem. 1992 Aug 15;47(3-4):241–248. doi: 10.1016/0162-0134(92)84069-y. [DOI] [PubMed] [Google Scholar]
  31. Valdivia R. H., Falkow S. Bacterial genetics by flow cytometry: rapid isolation of Salmonella typhimurium acid-inducible promoters by differential fluorescence induction. Mol Microbiol. 1996 Oct;22(2):367–378. doi: 10.1046/j.1365-2958.1996.00120.x. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES