Fatty Acid beta-Oxidation System in Microbodies of n-Alkane-Grown Candida tropicalis

Abstract

Localization of fatty acid .beta.-oxidation system in microbodies of C. tropicalis cells growing on n-alkanes was studied. Microbodies isolated from the yeast cells showed palmitate-dependent activities of NAD reduction, acetyl-CoA formation and O2 consumption. When sodium azide, an inhibitor of catalase, was added to the system, palmitate-dependent formation of H2O2 was observed. Stoichiometric study revealed that 2 mol of NAD were reduced per 1 mol of O2 consumed in the absence of sodium azide and the presence of the inhibitor doubled the O2 consumption by microbodies without an appreciable change in NAD reduction. Apparently the yeast microbodies contain .beta.-oxidation system of fatty acid and the catalase located in the organelles participates in the degradation of H2O2 formed at the step of dehydrogenation of acyl-CoA.