Effect of anisotropic inhibitors of ATP synthesis in mitochondria of Saccharomyces cerevisiae. Comparison between a wild-type and a mutant strain altered in the stoichiometry of the MT DNA encoded proteolipids of ATP synthase.
The effect of a group of non-usual inhibitors of ATP synthesis was investigated in yeast mitochondria. Tetraphenylphosphonium, tetraphenylarsonium and ethidium decreased the rate of ATP synthesis but did not decrease the ATP/O ratio. They did not inhibit the ATPase activity and the translocase, and did not decrease the proton-motive force. They inhibited phosphate transport under conditions in which it was strictly energy-dependent, but did not under conditions in which it was energy-independent. These inhibitors had a poor effect on ATP synthesis in mitochondria isolated from a nuclear mutant which contained a reduced amount of the subunits 8 and 6 of the Fo part of the ATP synthase as compared to wild-type and which were unable to support any energy-dependent phosphate-transport. Thus, it appeared that the phosphate-dependence of ATP synthesis was altered in the same way by both tetraphenylphosphonium and the mutation.
Institut de Biochimie Cellulaire du CNRS, Université de Bordeaux II, France.
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D000255:Adenosine Triphosphate / Q000096:biosynthesis*; D000970:Antineoplastic Agents / Q000633:toxicity; D001152:Arsenicals / Q000494:pharmacology*; D003470:Culture Media; D004272:DNA, Mitochondrial / Q000235:genetics; D004996:Ethidium / Q000494:pharmacology*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009154:Mutation; D009861:Onium Compounds / Q000494:pharmacology*; D009943:Organophosphorus Compounds / Q000494:pharmacology*; D010766:Phosphorylation; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
D000970:Antineoplastic Agents; D001152:Arsenicals; D003470:Culture Media; D004272:DNA, Mitochondrial; D009861:Onium Compounds; D009943:Organophosphorus Compounds; C009439:tetraphenylarsonium; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases; D004996:Ethidium; C013289:tetraphenylphosphonium