Muench Stephen P, Huss Markus, Song Chun Feng, Phillips Clair, Wieczorek Helmut, Trinick John, Harrison Michael A
Institute of Membrane and Systems Biology, Faculty of Biological Sciences, University of Leeds, LS2 9JT, UK.
J Mol Biol. 2009 Mar 6;386(4):989-99. doi: 10.1016/j.jmb.2009.01.014.
The vacuolar H+-ATPase (V-ATPase) is an ATP-driven rotary molecular motor that is a transmembrane proton pump in all eukaryotic cells. Although its activity is fundamental to many physiological processes, our understanding of the structure and mechanism of the V-ATPase is poor. Using cryo-electron microscopy of the tobacco hornworm (Manduca sexta) enzyme, we have calculated the first 3D reconstruction of the intact pump in its native state. The resolution of 16.5 A is significantly higher than that of previous cryo-electron microscopy models of either V-ATPase or the related F1F0-ATPase. A network of four stalk structures connecting the V1 catalytic domain and the V0 membrane domain is now fully resolved, demonstrating substantially greater complexity than that found in the F-ATPase. Three peripheral stator stalks connect these domains to a horizontal collar that partly encircles the region between V1 and V0. The fourth stalk is a central axle that connects to V0 but makes minimal contact with V1. Several subunit crystal structures can be fit accurately into the reconstruction. The model thus provides new insights into the organisation of key components involved in mechanical coupling between the domains and regulation of activity.
液泡H⁺-ATP酶（V-ATP酶）是一种由ATP驱动的旋转分子马达，是所有真核细胞中的跨膜质子泵。尽管其活性对许多生理过程至关重要，但我们对V-ATP酶的结构和机制了解甚少。通过对烟草天蛾（烟草天蛾）酶进行冷冻电子显微镜观察，我们首次计算出了完整泵在其天然状态下的三维重建结构。16.5埃的分辨率显著高于之前V-ATP酶或相关F1F0-ATP酶的冷冻电子显微镜模型。连接V1催化结构域和V0膜结构域的四个柄结构网络现已完全解析，显示出比F-ATP酶更大的复杂性。三个外周定子柄将这些结构域连接到一个水平环，该环部分环绕V1和V0之间的区域。第四个柄是一个中心轴，它连接到V0，但与V1的接触最少。几个亚基晶体结构可以准确地拟合到重建结构中。因此，该模型为深入了解结构域之间机械偶联和活性调节所涉及的关键组件的组织提供了新的见解。
