Rotation of the c subunit oligomer in fully functional F1Fo ATP synthase
Rotation of the c subunit oligomer in fully functional F1Fo ATP synthase
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DOI：
10.1073/pnas.031564198
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发表时间：
2001-01-30
影响因子：
11.1
通讯作者：
Capaldi, RA
中科院分区：
文献类型：
--
作者：
Tsunoda, SP;Aggeler, R;Capaldi, RA
F1 F0型ATP合酶是已知最小的运动酶。先前的研究已经确定，在催化过程中，F-1部分的中心γ和γ亚基相对于α（3）β（3）和δ亚基的定子旋转。我们现在证明F-0部分的c亚基环沿着与γ和γ亚基一起移动。这通过将三个转子亚基与半胱氨酸残基之间的二硫桥连接来证明，所述半胱氨酸残基在γ、γ和c亚基之间的界面处遗传地引入。通过使用CuCl 2诱导氧化，实现了γ、γ和c亚基的基本上完全交联。这三个亚基的固定在一起对ATP水解，质子转运或ATP合成没有显着影响，并且这些功能中的每一个都保留了抑制剂的敏感性。这些结果毫不含糊地将c亚基寡聚体放置在这个分子机器的转子部分。
The F1F0-type ATP synthase is the smallest motor enzyme known. Previous studies had established that the central gamma and epsilon subunits of the F-1 part rotate relative to a stator of alpha (3)beta (3) and delta subunits during catalysis. We now show that the ring of c subunits in the F-0 part moves along with the gamma and epsilon subunits. This was demonstrated by linking the three rotor subunits with disulfide bridges between cysteine residues introduced genetically at the interfaces between the gamma, epsilon, and c subunits. Essentially complete cross-linking of the gamma, epsilon, and c subunits was achieved by using CuCl2 to induce oxidation. This fixing of the three subunits together had no significant effect on ATP hydrolysis, proton translocation, or ATP synthesis, and each of these functions retained inhibitor sensitivity. These results unequivocally place the c subunit oligomer in the rotor part of this molecular machine.