Kiehl R, Hanstein W G
Biochim Biophys Acta. 1984 Aug 31;766(2):375-85. doi: 10.1016/0005-2728(84)90253-6.
Energy transduction in an ATPase complex (complex V) has been studied in two reactions catalyzed by this system, i.e., ATP-dependent spectral shift of oxonol VI, and ATP-Pi exchange activity. Aurovertin alone inhibits 50% of the oxonol shift at 2 microM, and no further inhibition occurs at up to 12 microM. In combination with even weakly effective uncouplers, 4 microM aurovertin fully abolishes the oxonol response. No such effects are observed in the presence of oligomycin and uncouplers. No pH gradient is detectable by quenching of 9-amino-6-chloro-2-methoxyacridine; and nigericin is without effect on the oxonol response. Valinomycin is inhibitory even in the absence of added potassium, due to ammonium ions introduced during the purification steps. Thiocyanate inhibits the dye response by only 10-27%, depending on the preparation. The extent of the oxonol response depends on the ATP/ADP ratio rather than the phosphorylation potential. The dye response in the ATPase complex is 4-7-times less sensitive to bile salts than in submitochondrial particles. The inhibition by cardiolipin can be reversed by the addition of phospholipids. The possibility is discussed that the oxonol response in the ATPase complex reflects, at least in part, a more local, ATP-dependent and energy-related process.
已在由该系统催化的两个反应中研究了ATP酶复合体（复合体V）中的能量转导，即奥克诺尔VI的ATP依赖性光谱位移和ATP-磷酸交换活性。单独的金褐霉素在2 microM时可抑制50%的奥克诺尔位移，在高达12 microM时不会进一步抑制。与即使是低效的解偶联剂联合使用时，4 microM金褐霉素可完全消除奥克诺尔反应。在存在寡霉素和解偶联剂的情况下未观察到此类效应。通过9-氨基-6-氯-2-甲氧基吖啶的猝灭无法检测到pH梯度；尼日利亚菌素对奥克诺尔反应无影响。缬氨霉素即使在未添加钾的情况下也具有抑制作用，这是由于纯化步骤中引入的铵离子所致。硫氰酸盐对染料反应的抑制作用仅为10%-27%，具体取决于制剂。奥克诺尔反应的程度取决于ATP/ADP比值而非磷酸化电位。ATP酶复合体中的染料反应对胆盐的敏感性比对线粒体亚颗粒中的染料反应低4-7倍。心磷脂的抑制作用可通过添加磷脂来逆转。文中讨论了一种可能性，即ATP酶复合体中的奥克诺尔反应至少部分反映了一个更局部的、ATP依赖性的和与能量相关的过程。
