Fo-driven Rotation in the ATP Synthase Direction against the Force of F1 ATPase in the FoF1 ATP Synthase.
Fo-driven Rotation in the ATP Synthase Direction against the Force of F1 ATPase in the FoF1 ATP Synthase.
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Fo 驱动的 ATP 合酶方向旋转对抗 FoF1 ATP 合酶中 F1 ATP 酶的力。
DOI：
10.1074/jbc.m115.646430
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Frasch,WayneD
中科院分区：
文献类型：
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作者：
Martin,James;Hudson,Jennifer;Hornung,Tassilo;Frasch,WayneD
生物体依靠 FoF1ATP 合酶来维持 ATP 到 ADP 和磷酸盐的非平衡化学梯度，为细胞过程提供主要能量来源。 Fomotor 如何使用跨膜电化学离子梯度来产生顺时针扭矩，从而克服高 ATP 下 F1ATPase 驱动的逆时针扭矩，这是一个尚未解决的主要问题。使用嵌入脂质双层纳米盘中的单个 FoF1 分子，我们现在报告观察到 c10 环在 ATP 合酶（顺时针）方向上依赖 Fo 的旋转，与 ATP 酶驱动的逆时针旋转力相反，这种旋转是在与 Fostator 亚基 a 形成束缚时发生的。突变研究表明，束缚对于 ATP 合酶活性很重要，并支持残基 aGlu-196 和 cArg-50 参与细胞质质子半通道以促进束缚形成的机制。
Living organisms rely on the FoF1ATP synthase to maintain the non-equilibrium chemical gradient of ATP to ADP and phosphate that provides the primary energy source for cellular processes. How the Fomotor uses a transmembrane electrochemical ion gradient to create clockwise torque that overcomes F1ATPase-driven counterclockwise torque at high ATP is a major unresolved question. Using single FoF1molecules embedded in lipid bilayer nanodiscs, we now report the observation of Fo-dependent rotation of the c10 ring in the ATP synthase (clockwise) direction against the counterclockwise force of ATPase-driven rotation that occurs upon formation of a leash with Fostator subunit a. Mutational studies indicate that the leash is important for ATP synthase activity and support a mechanism in which residues aGlu-196 and cArg-50 participate in the cytoplasmic proton half-channel to promote leash formation.