F₁ domain of ATP synthase is a rotary ATPase complex in which rotation of central γ-subunit proceeds in 120° steps against a surrounding α₃β₃ fueled by ATP hydrolysis. How the ATP hydrolysis reactions occurring in three catalytic αβ dimers are coupled to mechanical rotation is a key outstanding question. Here we describe catalytic intermediates of the F₁ domain in F_oF₁ synthase from Bacillus PS3 sp. during ATP mediated rotation captured using cryo-EM. The structures reveal that three catalytic events and the first 80° rotation occur simultaneously in F₁ domain when nucleotides are bound at all the three catalytic αβ dimers. The remaining 40° rotation of the complete 120° step is driven by completion of ATP hydrolysis at α_Dβ_D, and proceeds through three sub-steps (83°, 91°, 101°, and 120°) with three associated conformational intermediates. All sub-steps except for one between 91° and 101° associated with phosphate release, occur independently of the chemical cycle, suggesting that the 40° rotation is largely driven by release of intramolecular strain accumulated by the 80° rotation. Together with our previous results, these findings provide the molecular basis of ATP driven rotation of ATP synthases.

ATP 合酶的F ₁结构域是一种旋转 ATP 酶复合物，其中中心 γ 亚基以 120° 步长相对于周围由ATP 水解推动的α ₃ β _{3进行旋转。}三个催化 αβ 二聚体中发生的 ATP 水解反应如何与机械旋转耦合是一个关键的悬而未决的问题。在这里，我们描述了来自芽孢杆菌 PS3 sp 的F _o F _{1合酶中 F 1}结构域的催化中间体。使用冷冻电镜捕获 ATP 介导的旋转期间。_{该结构揭示了 F 1}中三个催化事件和第一个 80° 旋转同时发生当核苷酸结合在所有三个催化 αβ 二聚体上时，该结构域被称为“结构域”。_{完整的 120° 步骤的剩余 40° 旋转由 α D} β _D处的 ATP 水解完成驱动，并通过三个相关的构象中间体进行三个子步骤（83°、91°、101° 和 120°）。除了与磷酸盐释放相关的 91° 和 101° 之间的一个子步骤之外，所有子步骤都独立于化学循环而发生，这表明 40° 旋转很大程度上是由 80° 旋转积累的分子内应变的释放驱动的。与我们之前的结果一起，这些发现提供了 ATP 驱动的 ATP 合酶旋转的分子基础。