Ivanishchev Viktor V
Department of Biology and Technologies of Living Systems, Tula State Lev Tolstoy Pedagogical University, Lenin Ave., 125, Tula, 300026, Russia.
Biosystems. 2025 Aug;254:105493. doi: 10.1016/j.biosystems.2025.105493. Epub 2025 May 19.
The work is devoted to description of processes that provide fundamental conditions for ATP synthesis in vivo. The work presents information on the basis of which a general fundamental picture of formation of electrochemical gradient on the mitochondrial (or chloroplast) membrane and its use for ATP-synthase operation is described. An attempt was made to explain the order of appearance of electrical and chemical gradients, as well as the feedback between electrical and chemical components of the driving force in mitochondria and chloroplasts based on Nath's two-ion theory. The results of the analysis allowed us to conclude that a series of sequential events (which are separated in time and space) is necessary for ATP synthesis in vivo, namely: formation of electrical potential, formation of chemical potential, their use for ATP synthase operation. The electrical component is formed due to light energy (chloroplast) or metabolite-associated processes (mitochondria) by pumping of H by the electron transport chain. Formation of chemical gradients occur only upon collapse of the electrical gradient by counterion translocation. As a result of their interaction, a driving force (plus change in the conformation of membrane components) is formed on the membrane, which makes ATP-synthase work. The reasons for significant differences in the values of the chemical and electrical components of the gradient on the membranes of mitochondria and chloroplasts are shown (explained). Analysis of the active transport of metabolites from the mitochondria allows us to conclude that it is possible to "break" the concentration flow of Krebs cycle metabolites into mitochondria in vivo, which can be maintained by cytoplasmic malate.
这项工作致力于描述为体内ATP合成提供基本条件的过程。该工作呈现了相关信息,在此基础上描述了线粒体(或叶绿体)膜上电化学梯度形成的一般基本情况及其用于ATP合酶运作的情况。基于纳特的双离子理论,试图解释电势和化学势出现的顺序,以及线粒体和叶绿体中驱动力的电学和化学组分之间的反馈。分析结果使我们得出结论,体内ATP合成需要一系列连续事件(在时间和空间上是分开的),即:电势的形成、化学势的形成、它们用于ATP合酶的运作。电学组分是由于光能(叶绿体)或与代谢物相关的过程(线粒体)通过电子传递链泵出H而形成的。化学梯度仅在通过抗衡离子转运使电势梯度崩溃时才会形成。由于它们的相互作用,在膜上形成了驱动力(加上膜组分构象的变化),这使得ATP合酶发挥作用。展示(解释)了线粒体和叶绿体膜上梯度的化学和电学组分值存在显著差异的原因。对线粒体中代谢物主动转运的分析使我们得出结论,有可能在体内“打破”三羧酸循环代谢物进入线粒体的浓度流,而这可以由细胞质苹果酸维持。