Syroeshkin A V, Vasilyeva E A, Vinogradov A D
Department of Biochemistry, School of Biology, Moscow State University, Russian Federation.
FEBS Lett. 1995 Jun 5;366(1):29-32. doi: 10.1016/0014-5793(95)00487-t.
The ADP(Mg2+)-deactivated oligomycin-sensitive F1-F0 ATPase of coupled submitochondrial particles treated with the substoichiometric amount of oligomycin was studied to test whether ATP synthesis and hydrolysis proceed in either direction through the same intermediates. The initial rates of ATP hydrolysis, oxidative phosphorylation, ATP-dependent, succinate-supported NAD+ reduction, and ATP-induced delta microH+ generation were measured using deactivated ATPase trapped by azide [Biochem. J. (1982) 202, 15-23]. Three ATP consuming reactions were strongly inhibited when azide was present in the assay mixtures, whereas ATP synthesis was not altered by azide. The unidirectional effect of azide is not consistent with three alternating binding sites mechanism operating in ATP synthesis and support our hypothesis on the existence of nucleotide(Mg2+)-controlled 'synthase' and 'hydrolase' states of the mitochondrial F1-F0 ATPase.
用亚化学计量的寡霉素处理的偶联亚线粒体颗粒的 ADP（Mg2+）失活的寡霉素敏感 F1-F0 ATP 合酶，被用于研究 ATP 的合成和水解是否通过相同的中间体在任一方向上进行。使用叠氮化物捕获的失活 ATP 合酶来测量 ATP 水解、氧化磷酸化、ATP 依赖性琥珀酸支持的 NAD+还原以及 ATP 诱导的 ΔμH+产生的初始速率[《生物化学杂志》（1982 年）202 卷，15 - 23 页]。当测定混合物中存在叠氮化物时，三个消耗 ATP 的反应受到强烈抑制，而 ATP 的合成不受叠氮化物影响。叠氮化物的单向作用与在 ATP 合成中起作用的三个交替结合位点机制不一致，并支持我们关于线粒体 F1-F0 ATP 合酶存在核苷酸（Mg2+）控制的“合成酶”和“水解酶”状态的假设。
