Oligomycin-dependent ionophoric protein subunit of mitochondrial adenosinetriphosphatase.
A proteolipid isolated from yeast mitochondrial adenosinetriphosphatase (subunit 9) (ATP phosphohydrolase; EC 3.6.1.3) by chloroform/methanol extraction has been shown to discharge photo-induced potentials across a planar phospholipid membrane containing bacteriorhodopsin. Oligomycin, a specific inhibitor of oxidative phosphorylation which binds to this protein, allows the potential gradient to be reestablished. When proteolipid was isolated from an oligomycin-resistant strain, ionophoric activity was still obtained but the effect was not reversed by oligomycin. These studies suggest that the hydrophobic subunit-9 polypeptide is the ionophoric component linking ATP synthesis (hydrolysis) with proton translocation.
D000251:Adenosine Triphosphatases; D001436:Bacteriorhodopsins; D055598:Chemical Phenomena; D002621:Chemistry; D004352:Drug Resistance, Microbial; D005374:Filtration; D005656:Fungal Proteins / Q000032:analysis*; D007476:Ionophores / Q000032:analysis*; D008055:Lipids; D008567:Membranes, Artificial; D008928:Mitochondria / Q000201:enzymology*; D009840:Oligomycins / Q000494:pharmacology*; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D013997:Time Factors
D005656:Fungal Proteins; D007476:Ionophores; D008055:Lipids; D008567:Membranes, Artificial; D009840:Oligomycins; D001436:Bacteriorhodopsins; D000251:Adenosine Triphosphatases