National Research Center "Kurchatov Institute", Moscow, 123182, Russia.
Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia.
Biochemistry (Mosc). 2022 Feb;87(2):179-190. doi: 10.1134/S0006297922020092.
In this review, we discuss the mechanisms of generation of membrane-bound protons using different energy sources in model and natural systems. Analysis of these mechanisms revealed that all three types of reactions include the same principal stage, which is dissociation of electrically neutral Brønsted acids at the interface during transition from the hydrophobic phase to water with a low dielectric constant. Special attention is paid to the fact that in one of the analyzed model systems, membrane-bound protons provide energy for the reaction of ATP synthesis. Similar mechanism for the generation of membrane-bound protons has been found in natural membranes involved in oxidative phosphorylation, in particular, on the membranes of mitoplasts and mitochondria. The energy of oxidative reactions required for ATP synthesis, is stored at the intermediate stage not only in the form of transmembrane electrochemical potential of protons, but also and perhaps mostly, as protons attached to the inner mitochondrial membrane. The process of energy storage in mitochondria is linked to the transfer of protons that simultaneously perform two functions. Protons on the membrane surface carry free energy and, at the same time, act as substrates facilitating the movement of FF-ATP-synthase biological machine.
在这篇综述中，我们讨论了使用不同能量源在模型和天然系统中产生膜结合质子的机制。对这些机制的分析表明，所有三种类型的反应都包括相同的主要阶段，即在疏水性相到低介电常数水的转变过程中，电中性布朗斯台德酸在界面处的离解。特别值得注意的是，在分析的一个模型系统中，膜结合质子为 ATP 合成反应提供能量。在涉及氧化磷酸化的天然膜中，特别是在线粒体和线粒体的类线粒体膜中，发现了产生膜结合质子的类似机制。氧化反应所需的能量用于 ATP 合成，不仅以质子跨膜电化学势的形式，而且可能主要以附着在内膜上的质子的形式储存在中间阶段。在线粒体中能量的储存与质子的转移有关，质子同时执行两个功能。膜表面上的质子携带自由能，同时作为促进 FF-ATP 合酶生物机器运动的底物。
