Energy transduction in the F1 motor of ATP synthase
Energy transduction in the F1 motor of ATP synthase
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DOI：
10.1038/24409
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发表时间：
1998-11
期刊：
影响因子：
64.8
通讯作者：
Hongyun Wang;G. Oster
中科院分区：
文献类型：
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作者：
Hongyun Wang;G. Oster
ATP 合酶是一种通用酶，它利用跨膜质子动力梯度产生的能量，从 ADP 和磷酸盐生产 ATP。它还可以自行反转并水解 ATP，以逆着电化学梯度泵送质子。 ATP 合酶通过旋转机制进行合成和水解循环。在分离蛋白质的可溶性 F1 部分并可视化酶的中心“轴”相对于分子其余部分的实际旋转之后，这一点在水解方向得到了证实，使 ATP 合酶成为世界上最小的旋转发动机。在这里，我们提出了该发动机的模型，该模型解释了其在水解和合成方向上的机械化学行为。我们得出的结论是，F1 电机实现了高机械扭矩和几乎 100% 的效率，因为它将 ATP 结合的自由能转化为弹性应变，然后通过协调的动力学和紧密耦合的构象机制释放弹性应变，以产生旋转扭矩。
ATP synthase is the universal enzyme that manufactures ATP from ADP and phosphate by using the energy derived from a transmembrane protonmotive gradient. It can also reverse itself and hydrolyse ATP to pump protons against an electrochemical gradient. ATP synthase carries out both its synthetic and hydrolytic cycles by a rotary mechanism,,,. This has been confirmed in the direction of hydrolysis, after isolation of the soluble F1portion of the protein and visualization of the actual rotation of the central ‘shaft’ of the enzyme with respect to the rest of the molecule, making ATP synthase the world's smallest rotary engine. Here we present a model for this engine that accounts for its mechanochemical behaviour in both the hydrolysing and synthesizing directions. We conclude that the F1motor achieves its high mechanical torque and almost 100% efficiency because it converts the free energy of ATP binding into elastic strain, which is then released by a coordinated kinetic and tightly coupled conformational mechanism to create a rotary torque.