Factors contributing to hydrogen peroxide resistance in Streptococcus pneumoniae include pyruvate oxidase (SpxB) and avoidance of the toxic effects of the fenton reaction.

ABSTRACT: Aerobic growth of Streptococcus pneumoniae results in production of amounts of hydrogen peroxide (H(2)O(2)) that may exceed 1 mM in the surrounding media. H(2)O(2) production by S. pneumoniae has been shown to kill or inhibit the growth of other respiratory tract flora, as well as to have cytotoxic effects on host cells and tissue. The mechanisms allowing S. pneumoniae, a catalase-deficient species, to survive endogenously generated concentrations of H(2)O(2) that are sufficient to kill other bacterial species is unknown. In the present study, pyruvate oxidase (SpxB), the enzyme responsible for endogenous H(2)O(2) production, was required for survival during exposure to high levels (20 mM) of exogenously added H(2)O(2). Pretreatment with H(2)O(2) did not increase H(2)O(2) resistance in the

SUBMITTER: Pericone CD 

PROVIDER: S-EPMC262707 | biostudies-literature | 2003 Dec

REPOSITORIES: biostudies-literature