Growth of catalase A and catalase T deficient mutant strains of Saccharomyces cerevisiae on ethanol and oleic acid

Abstract

The parental strain (A+T+) of Saccharomyces cerevisiae and mutants, deficient in catalase T (A+T−), catalase A (A−T+) or both catalases (A−T−), grew on ethanol and oleic acid with comparable doubling times. Specific activities of catalase were low in glucose- and ethanol-grown cells. In the two oleic acid-grown A+-strains (A+T+ and A+T−) high catalase activities were found; catalase activity invariably remained low in the A−T+ strain and was never detected in the A−T− strain. The levels of β-oxidation enzymes in oleic acid-grown cells of the parental and all mutant strains were not significantly different. However, cytochrome C peroxidase activity had increased 8-fold in oleic acid grown A− strains (A−T+ and A−T−) compared to parental strain cells. The degree of peroxisomal proliferation was comparable among the different strains. Catalase A was shown to be located in peroxisomes. Catalase T is most probably cytosolic in nature and/or present in the periplasmic space.