Structure-function analyses of alkylhydroperoxidase D from Streptococcus pneumoniae reveal an unusual three-cysteine active site architecture.

ABSTRACT: During aerobic growth, the Gram-positive facultative anaerobe and opportunistic human pathogen Streptococcus pneumoniae generates large amounts of hydrogen peroxide that can accumulate to millimolar concentrations. The mechanism by which this catalase-negative bacterium can withstand endogenous hydrogen peroxide is incompletely understood. The enzyme alkylhydroperoxidase D (AhpD) has been shown to contribute to pneumococcal virulence and oxidative stress responses in vivo We demonstrate here that SpAhpD exhibits weak thiol-dependent peroxidase activity and, unlike the previously reported Mycobacterium tuberculosis AhpC/D system, SpAhpD does not mediate electron transfer to SpAhpC. A 2.3-Å resolution crystal structure revealed several unusual struct

SUBMITTER: Meng Y 

PROVIDER: S-EPMC7062192 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature