Abstract：
The light-induced transthylakoid membrane potential (ΔΨm) can function as a driving force to help catalyzing the formation of ATP molecules, proving a tight connection between ΔΨm and the ATP synthase. Naturally, a question can be raised on the effects of altered functioning of ATP synthases on regulating ΔΨm, which is attractive in the area of photosynthetic research. Lots of findings, when making efforts of solving this difficulty, can offer an in-depth understanding into the mechanism behind. However, the functional network on modulating ΔΨm is highly interdependent. It is difficult to comprehend the consequences of altered activity of ATP synthases on adjusting ΔΨm because parameters that have influences on ΔΨm would themselves be affected by ΔΨm. In this work, a computer model was applied to check the kinetic changes in polarization/depolarization across the thylakoid membrane (TM) regulated by the modified action of ATP synthases. The computing data revealed that under the extreme condition by numerically \"switching off\" the action of the ATP synthase, the complete inactivation of ATP synthase would markedly impede proton translocation at the cytb6f complex. Concurrently, the KEA3 (CLCe) porter, actively pumping protons into the stroma, further contributes to achieving a sustained low level of ΔΨm. Besides, the quantitative consequences on every particular component of ΔΨm adjusted by the modified functioning of ATP synthases were also explored. By employing the model, we bring evidence from the theoretical perspective that the ATP synthase is a key factor in forming a transmembrane proton loop thereby maintaining a propriate steady-state ΔΨm to meet variable environmental conditions.
摘要：
光诱导的类囊体膜电位（ΔΦm）可以作为驱动力来帮助催化ATP分子的形成，证明了ΔWm和ATP合酶之间的紧密联系。自然,可以提出一个关于ATP合酶功能改变对调节ΔkW的影响的问题，这在光合研究领域很有吸引力。很多发现,在努力解决这个困难时，可以深入了解背后的机制。然而,调制ΔkW的功能网络是高度相互依赖的。很难理解ATP合酶活性改变对调整ΔkWm的影响，因为对ΔkWm有影响的参数本身会受到ΔkWm的影响。在这项工作中,应用计算机模型来检查由ATP合酶的修饰作用调节的类囊体膜（TM）上极化/去极化的动力学变化。计算数据显示，在极端条件下，通过数值“关闭”ATP合酶的作用，ATP合酶的完全失活将显著阻碍cytb6f复合物的质子易位。同时,KEA3(CLCe)搬运工，积极地将质子泵入基质，进一步有助于实现持续的低水平ΔkW。此外,还探索了通过ATP合酶的功能改变而调节的ΔkW的每个特定成分的定量结果。通过使用该模型，我们从理论角度提供了证据，表明ATP合酶是形成跨膜质子环的关键因素，从而保持适当的稳态Δwm以满足可变的环境条件。
