Controlled rotation of the F₁-ATPase reveals differential and continuous binding changes for ATP synthesis.
Controlled rotation of the F₁-ATPase reveals differential and continuous binding changes for ATP synthesis.
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DOI：
10.1038/ncomms2026
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发表时间：
2012
影响因子：
16.6
通讯作者：
中科院分区：
文献类型：
--
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F1-ATP酶是ATP驱动的旋转分子马达，当反向旋转时合成ATP。为了阐明ATP合成的机制，我们成像的结合和释放的荧光标记的ADP和ATP，同时旋转电机在任一方向的磁铁。在这里，我们报告了360°旋转角的三个催化位点中的每一个的结合和释放速率。我们发现，速率并不显着依赖于旋转方向，表明ATP合成的直接逆转的水解驱动的旋转。ADP和ATP在角度依赖性结合中有区别，但在释放中没有区别。磷酸盐以ADP结合对ATP合成至关重要的角度阻断ATP结合。在合成旋转中，对ADP的亲和力增加>104，然后转变为高ATP亲和力，最后对ATP的亲和力降低>104。所有这些角度变化是渐进的，暗示转子角度和位置亲和力之间的紧密耦合。F1-ATP酶的反向旋转导致ATP的合成，而不是水解。阿达奇等人表明，ATP合成的分子机制是水解驱动的马达旋转的逆过程，ADP和ATP通过角度依赖性结合来区分。
F1-ATPase is an ATP-driven rotary molecular motor that synthesizes ATP when rotated in reverse. To elucidate the mechanism of ATP synthesis, we imaged binding and release of fluorescently labelled ADP and ATP while rotating the motor in either direction by magnets. Here we report the binding and release rates for each of the three catalytic sites for 360° of the rotary angle. We show that the rates do not significantly depend on the rotary direction, indicating ATP synthesis by direct reversal of the hydrolysis-driven rotation. ADP and ATP are discriminated in angle-dependent binding, but not in release. Phosphate blocks ATP binding at angles where ADP binding is essential for ATP synthesis. In synthesis rotation, the affinity for ADP increases by >104, followed by a shift to high ATP affinity, and finally the affinity for ATP decreases by >104. All these angular changes are gradual, implicating tight coupling between the rotor angle and site affinities. Reverse rotation of the F1-ATPase results in the synthesis, rather than hydrolysis of ATP. Adachi et al. show that the molecular mechanism of ATP synthesis is the reverse of hydrolysis-driven rotation of the motor, and that ADP and ATP are discriminated by angle-dependent binding.
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影响因子：
--
作者：
Oosawa, F;Hayashi, S
通讯作者：
Hayashi, S
影响因子：
3.4
作者：
Sakaki, N;Shimo-Kon, R;Kinosita, K
通讯作者：
Kinosita, K
影响因子：
16.8
作者：
Ariga, Takayuki;Muneyuki, Eiro;Yoshida, Masasuke
通讯作者：
Yoshida, Masasuke
影响因子：
16.8
作者：
Masaike, Tomoko;Koyama-Horibe, Fumie;Nishizaka, Takayuki
通讯作者：
Nishizaka, Takayuki
DOI：
10.1073/pnas.2434983100
发表时间：
2003-12-09
影响因子：
11.1
作者：
Shimabukuro, K;Yasuda, R;Yoshida, M
通讯作者：
Yoshida, M