Tedeschi H
Biochim Biophys Acta. 1981 Dec 30;639(3-4):157-96. doi: 10.1016/0304-4173(81)90009-4.
The present paper has reviewed several factors related to ion transport and examined the properties of cation transport in mitochondria. The analysis suggests that: (1) The concept that a metabolically dependent electrical potential across the mitochondrial membrane plays a role in determining ion fluxes and steady-state concentrations is not justified and the data indicate that such exchanges are generally electroneutral. (2) Generally, the influx and efflux of an ion proceed by the same mechanism with at least one exception. (3) There are indications that some of the steps in transport are common to several cations. (4) The idea that carrier or ionophoric molecules are involved in cation transport has been examined in some detail together with the possible involvement of some known mitochondrial components. In particular, a model has been introduced in which local charge imbalances produced by H+ fluxes serve as the driving force of transport. The molecules of the complex are arranged in series in a tripartite arrangement including a filter or gate, a nonselective channel and an H+-transferring portion linked to either electron transport or the ATPase. Parts of this model have been introduced by other investigators. Models in which different portions of channels have differing functions have been proposed previously for other transport systems.
本文回顾了与离子转运相关的几个因素，并研究了线粒体中阳离子转运的特性。分析表明：（1）认为跨线粒体膜的代谢依赖性电势在决定离子通量和稳态浓度中起作用的观点是不合理的，数据表明此类交换通常是电中性的。（2）一般来说，离子的流入和流出通过相同的机制进行，至少有一个例外。（3）有迹象表明，转运过程中的一些步骤是几种阳离子共有的。（4）已经详细研究了载体或离子载体分子参与阳离子转运的观点以及一些已知线粒体成分可能的参与情况。特别是，引入了一个模型，其中H⁺通量产生的局部电荷失衡作为转运的驱动力。该复合物的分子以三方排列串联排列，包括一个过滤器或门、一个非选择性通道以及与电子传递或ATP酶相连的H⁺转移部分。该模型的部分内容已由其他研究人员提出。先前已针对其他转运系统提出了通道不同部分具有不同功能的模型。
