The evolution of A-, F-, and V-type ATP synthases and ATPascs:: reversals in function and changes in the H+/ATP coupling ratio
The evolution of A-, F-, and V-type ATP synthases and ATPascs:: reversals in function and changes in the H+/ATP coupling ratio
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DOI：
10.1016/j.febslet.2004.08.065
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发表时间：
2004-10-08
期刊：
影响因子：
3.5
通讯作者：
Müller, V
中科院分区：
文献类型：
--
作者：
Cross, RL;Müller, V
ATP合成酶和ATPase的F0F1、A(0)A(1)和V0V1家族成员至少经历了两次初级功能逆转。第一个是从质子泵ATPase的前体到质子驱动的ATP合成酶。第二项研究涉及将合成酶重新转化为质子泵ATPase。如早先提出的[FEBS Lett.259(1990)227]，这些逆转需要将H+/ATP偶联比从ATPase功能的最佳值约2改变到ATP合成酶功能的约4。通过复制编码核苷酸结合催化亚基的基因，然后失去其中一个基因的功能，发生在ATPase到合成酶转变过程中的比率加倍。在Synthaseto-ATPase转变过程中发生的比率减半是通过编码质子结合转运体亚单位的基因的复制/融合实现的，随后是双倍大小的蛋白质的一半功能丧失。这些事件允许保存四元结构，同时保持足够的驱动力以维持足够的磷酸化电位或电化学梯度。在这里，我们描述了中间的进化步骤和H+/ATP偶联比率的微调，以优化合酶功能以响应不同的环境。此外，我们提出了第三种功能逆转，从ATPase回到ATP合成酶。与需要部分功能损失的前两个反转相反，第三个反转所需的耦合比的变化由功能增益来解释。(C)2004年欧洲生化学会联合会。爱思唯尔出版，版权所有。
Members of the F0F1, A(0)A(1) and V0V1 family of ATP synthases and ATPases have undergone at least two reversals in primary function. The first was from a progenitor proton-pumping ATPase to a proton-driven ATP synthase. The second involved transforming the synthase back into a proton-pumping ATPase. As proposed earlier [FEBS Lett. 259 (1990) 227], these reversals required changes in the H+/ATP coupling ratio from an optimal value of about 2 for an ATPase function to about 4 for an ATP synthase function. The doubling of the ratio that occurred at the ATPase-to-Synthase transition was accomplished by duplicating the gene that encodes the nucleotide-binding catalytic subunits followed by loss of function in one of the genes. The halving of the ratio that occurred at the Synthaseto-ATPase transition was achieved by a duplication/fusion of the gene that encodes the proton-binding transporter subunits, followed by a loss of function in one half of the double-sized protein. These events allowed conservation of quaternary structure, while maintaining a sufficient driving force to sustain an adequate phosphorylation potential or electrochemical gradient. Here, we describe intermediate evolutionary steps and a fine-tuning of the H+/ATP coupling ratio to optimize synthase function in response to different environments. In addition, we propose a third reversal of function, from an ATPase back to an ATP synthase. In contrast to the first two reversals which required a partial loss in function, the change in coupling ratio required for the third reversal is explained by a gain in function. (C) 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.