Fatty acids induced uncoupling of Saccharomyces cerevisiae mitochondria requires an intact ADP/ATP carrier.
Fatty acids stimulate the oxidation rate of mitochondria isolated from the wild-type Saccharomyces cerevisiae, but do not affect significantly the respiration of mitochondria isolated from mutants, in which the ADP/ATP carrier (AAC) was either modified (R96H) or deleted (delta aac2). Similarly as in mammalian mitochondria, the transmembrane electrical potential difference (delta psi) in the wild-type yeast mitochondria was dissipated by low concentrations of free fatty acids, and this was partially inhibited by bongkrecate. In contrast to the wild-type mitochondria, the addition of increasing concentrations of fatty acids to the op1 (R96H) mutant mitochondria abolished only a small portion of delta psi, as compared to the change induced by classical uncouplers. The different effects of fatty acids on both, the respiration and the delta psi of mitochondria isolated from the wild-type and the aac mutants, respectively, demonstrates that the intact AAC is essential for the fatty acids induced H+ permeability of mitochondrial membrane.
Polcic
P
P
Department of Biochemistry, Faculty of Sciences, Comenius University, Bratislava, Slovakia.
Sabová
L
L
Kolarov
J
J
D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone / Q000494:pharmacology; D005227:Fatty Acids / Q000494:pharmacology*; D017353:Gene Deletion; D008564:Membrane Potentials; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism*; D000226:Mitochondrial ADP, ATP Translocases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016296:Mutagenesis; D019301:Oleic Acid / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects; D019308:Palmitic Acid / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D013329:Structure-Activity Relationship; D014475:Uncoupling Agents / Q000494:pharmacology*
D005227:Fatty Acids; D014475:Uncoupling Agents; D019301:Oleic Acid; D019308:Palmitic Acid; D002258:Carbonyl Cyanide m-Chlorophenyl Hydrazone; D000226:Mitochondrial ADP, ATP Translocases