Yasuda R, Noji H, Kinosita K, Yoshida M
Department of Physics, Faculty of Science and Technology, Keio University, Yokohama, Japan.
Cell. 1998 Jun 26;93(7):1117-24. doi: 10.1016/s0092-8674(00)81456-7.
A single molecule of F1-ATPase, a portion of ATP synthase, is by itself a rotary motor in which a central gamma subunit rotates against a surrounding cylinder made of alpha3beta3 subunits. Driven by three catalytic betas, each fueled with ATP, gamma makes discrete 120 degree steps, occasionally stepping backward. The work done in each step is constant over a broad range of imposed load and is close to the free energy of hydrolysis of one ATP molecule.
F1-ATP酶（ATP合酶的一部分）的单个分子本身就是一个旋转马达，其中央γ亚基围绕由α3β3亚基组成的周围圆柱体旋转。由三个催化β亚基驱动，每个β亚基由ATP提供能量，γ亚基进行离散的120度步移，偶尔也会向后步移。在广泛的外加负载范围内，每个步移所做的功是恒定的，并且接近一个ATP分子水解的自由能。
