ADAPTIVE RESPONSE OF SCHIZOSACCHAROMYCES-POMBE TO HYDROGEN-PEROXIDE

Schizosaccharomyces pombe becomes resistant to killing by high concent ration of hydrogen peroxide and other severe stresses including oxidan ts, high temperature and high concentration of ethanol when pretreated with nonlethal levels of hydrogen peroxide. In the presence of the pr otein synthesis inhibitor, cycloheximide, during hydrogen peroxide pre treatment, the cell obtained partial resistance to a higher level of h ydrogen peroxide. The partial resistance to hydrogen peroxide in the p resence of cycloheximide was acquired within 30 min of pretreatment bu t complete resistance obtained with de novo protein synthesis was not attained before 45 min of pretreatment. During adaptation to hydrogen peroxide, at least 15 polypeptides are induced, as analyzed by two-dim ensional gel electrophoresis. Catalase activity is induced eight-fold by treatment with a nonlethal level of hydrogen peroxide.