title: Induction and subcellular localization of enzymes participating in propionate metabolism in Candida tropicalis.
abstract: Candida tropicalis, a representative alkane- and higher fatty acid-utilizing yeast, can grow on propionate used as sole carbon and energy source. Initial pH of the medium markedly affected the growth of the yeast on propionate. In propionate-grown cells, several enzymes associated with peroxisomes and/or participating in propionate metabolism were induced in connection with the appearance of the characteristic peroxisomes. Acetate-grown cells of this yeast had only few peroxisomes, while alkane-grown cells contained conspicuous numbers of the organelles. As compared with alkane-grown cells, some specific features were observed in peroxisomes and enzymes associated with the organelles of propionate-grown cells: The shape of peroxisomes was large but the number was small; unlike localization of catalase in peroxisomes of alkane-grown cells, the enzyme of propionate-grown cells was mainly localized in cytoplasm; as for carnitine acetyltransferase localized almost equally in peroxisomes and mitochondria in alkane-grown cells, propionate-grown cells contained mainly the mitochondrial type enzyme. A propionate-activating enzyme, which was different from acetyl-CoA synthetase, was also induced in cytoplasm of propionate-grown cells. The role of carnitine acetyltransferase and the propionate-activating enzyme in propionate metabolism is discussed in comparison with the role of carnitine acetyltransferase and acetyl-CoA synthetase in acetate metabolism.
mesh_terms: D002175:Candida / Q000201:enzymology*; D002332:Carnitine O-Acetyltransferase / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D004790:Enzyme Induction; D006863:Hydrogen-Ion Concentration; D008854:Microscopy, Electron; D011422:Propionates / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D011422:Propionates; D002374:Catalase; D002332:Carnitine O-Acetyltransferase