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The Helicobacter pylori MutS protein confers protection from oxidative DNA damage.
- Source :
-
Molecular Microbiology . Oct2005, Vol. 58 Issue 1, p166-176. 11p. - Publication Year :
- 2005
-
Abstract
- The human gastric pathogenic bacterium Helicobacter pylori lacks a MutSLH-like DNA mismatch repair system. Here, we have investigated the functional roles of a mutS homologue found in H. pylori, and show that it plays an important physiological role in repairing oxidative DNA damage. H. pylori mutS mutants are more sensitive than wild-type cells to oxidative stress induced by agents such as H2O2, paraquat or oxygen. Exposure of mutS cells to oxidative stress results in a significant (∼10-fold) elevation of mutagenesis. Strikingly, most mutations in mutS cells under oxidative stress condition are G:C to T:A transversions, a signature of 8-oxoguanine (8-oxoG). Purified H. pylori MutS protein binds with a high specific affinity to double-stranded DNA (dsDNA) containing 8-oxoG as well as to DNA Holliday junction structures, but only weakly to dsDNA containing a G:A mismatch. Under oxidative stress conditions, mutS cells accumulate higher levels (approximately threefold) of 8-oxoG DNA lesions than wild-type cells. Finally, we observe that mutS mutant cells have reduced colonization capacity in comparison to wild-type cells in a mouse infection model. [ABSTRACT FROM AUTHOR]
- Subjects :
- *HELICOBACTER pylori
*PROTEINS
*DNA damage
*OXIDATIVE stress
*PHYSIOLOGY
*MUTAGENESIS
Subjects
Details
- Language :
- English
- ISSN :
- 0950382X
- Volume :
- 58
- Issue :
- 1
- Database :
- Academic Search Index
- Journal :
- Molecular Microbiology
- Publication Type :
- Academic Journal
- Accession number :
- 18257776
- Full Text :
- https://doi.org/10.1111/j.1365-2958.2005.04833.x