title: Association of Helicobacter pylori antioxidant activities with host colonization proficiency.
abstract: To assess the importance of two separate antioxidant activities in Helicobacter pylori, we tested the abilities of strains with mutations in either tpx (encoding thiolperoxidase) or ahpC (encoding alkyl hydroperoxide reductase [AhpC]) to colonize the stomachs of mice. The tpx strain was clearly more sensitive than the parent strain to both oxygen and cumene hydroperoxide. The strain colonized only 5% of the inoculated mice. Two different classes of oxygen-sensitive ahpC mutants in the type strain (ATCC 43504) were recently described (A. A. Olczak, J. W. Olson, and R. J. Maier, J. Bacteriol. 184:3186-3193, 2002). The same two classes of mutants were recovered upon ahpC mutagenesis of the mouse-adapted strain, SS1. Neither of these mutants was able to colonize mouse stomachs, whereas 78% of the mice inoculated with the parent strain became H. pylori positive.
authors.affiliation: Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA.
authors.forename: Adriana A
authors.initials: AA
authors.lastname: Olczak
authors.forename: Richard W
authors.initials: RW
authors.lastname: Seyler
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Olson
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Maier
mesh_terms: D000818:Animals; D001555:Benzene Derivatives / Q000494:pharmacology; D016481:Helicobacter Infections / Q000382:microbiology; D016480:Helicobacter pylori / Q000235:genetics / Q000254:growth & development*; D051379:Mice; D008810:Mice, Inbred C57BL; D008826:Microbial Sensitivity Tests; D009154:Mutation; D018384:Oxidative Stress; D010100:Oxygen / Q000494:pharmacology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D054464:Peroxiredoxins; D010940:Plant Proteins; D013270:Stomach / Q000382:microbiology*
chemical_list: D001555:Benzene Derivatives; D010940:Plant Proteins; D010544:Peroxidases; D054464:Peroxiredoxins; C087772:TPX1 protein, Lycopersicon esculentum; C007164:cumene hydroperoxide; D010100:Oxygen