Superoxide radicals have a protective role during H2O2 stress.

ABSTRACT: Reactive oxygen species (ROS) consist of potentially toxic, partly reduced oxygen species and free radicals. After H(2)O(2) treatment, yeast cells significantly increase superoxide radical production. Respiratory chain complex III and possibly cytochrome b function are essential for this increase. Disruption of complex III renders cells sensitive to H(2)O(2) but not to the superoxide radical generator menadione. Of interest, the same H(2)O(2)-sensitive mutant strains have the lowest superoxide radical levels, and strains with the highest resistance to H(2)O(2) have the highest levels of superoxide radicals. Consistent with this correlation, overexpression of superoxide dismutase increases sensitivity to H(2)O(2), and this phenotype is partially rescued by addition of small concentrations o

SUBMITTER: Thorpe GW 

PROVIDER: S-EPMC3771949 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature