Immunoelectron Microscopic Localization of Thiolases, β-Oxidation Enzymes of an n-Alkane-Utilizable Yeast, Candida tropicalis

Abstract

The location of acetoacetyl-CoA thiolase (T-I) and 3-ketoacyI-CoA thiolase (T-III), enzymes of the fatty acid, β-oxidation system, was studied in n-alkane-grown Candida tropicalis cells by immunoelectron microscopy using a post-embedding method with colloidal gold conjugated IgG. The deposition of gold particles for T-I was detected in the microbodies and cytoplasm and that of gold particles for T-III specifically in the mi-crobodies. The double labeling technique confirmed that T-I and T-III occurred concurrently in a microbody and T-I also in cytoplasm. These results were consistent with the biochemical data based on subcellular fractionation and indicated that the yeast β-oxidation system operates efficiently only in the microbodies. © 1992, Japan Society for Cell Biology. All rights reserved.