Iino Ryota, Noji Hiroyuki
Department of Applied Chemistry, the University of Tokyo, Tokyo, Japan.
Biochim Biophys Acta. 2012 Oct;1817(10):1732-9. doi: 10.1016/j.bbabio.2012.03.011. Epub 2012 Mar 16.
F(1)-ATPase is a rotary motor protein in which 3 catalytic β-subunits in a stator α(3)β(3) ring undergo unidirectional and cooperative conformational changes to rotate the rotor γ-subunit upon adenosine triphosphate hydrolysis. The prevailing view of the mechanism behind this rotary catalysis elevated the γ-subunit as a "dictator" completely controlling the chemical and conformational states of the 3 catalytic β-subunits. However, our recent observations using high-speed atomic force microscopy clearly revealed that the 3 β-subunits undergo cyclic conformational changes even in the absence of the rotor γ-subunit, thus dethroning it from its dictatorial position. Here, we introduce our results in detail and discuss the possible operating principle behind the F(1)-ATPase, along with structurally related hexameric ATPases, also mentioning the possibility of generating hybrid nanomotors. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).
F(1)-ATP酶是一种旋转马达蛋白，在定子α(3)β(3)环中的3个催化β亚基在三磷酸腺苷水解时会发生单向协同构象变化，从而使转子γ亚基旋转。这种旋转催化背后机制的主流观点认为，γ亚基是一个“独裁者”，完全控制着3个催化β亚基的化学和构象状态。然而，我们最近使用高速原子力显微镜的观察结果清楚地表明，即使在没有转子γ亚基的情况下，3个β亚基也会发生周期性构象变化，从而将其从独裁地位上拉下马。在这里，我们详细介绍我们的结果，并讨论F(1)-ATP酶以及结构相关的六聚体ATP酶背后可能的工作原理，还提及了生成混合纳米马达的可能性。本文是名为“第17届欧洲生物能量学会议（EBEC 2012）”特刊的一部分。
