Department of Cell Biology, University of Kaiserslautern, Erwin-Schrödinger-Strasse 13, 67663 Kaiserslautern, Germany.
J Biol Chem. 2012 Feb 10;287(7):4426-33. doi: 10.1074/jbc.R111.270678. Epub 2011 Dec 6.
99% of all mitochondrial proteins are synthesized in the cytosol, from where they are imported into mitochondria. In contrast to matrix proteins, many proteins of the intermembrane space (IMS) lack presequences and are imported in an oxidation-driven reaction by the mitochondrial disulfide relay. Incoming polypeptides are recognized and oxidized by the IMS-located receptor Mia40. Reoxidation of Mia40 is facilitated by the sulfhydryl oxidase Erv1 and the respiratory chain. Although structurally unrelated, the mitochondrial disulfide relay functionally resembles the Dsb (disufide bond) system of the bacterial periplasm, the compartment from which the IMS was derived 2 billion years ago.
线粒体的 99%的蛋白质都是在细胞质中合成的，然后再被运送到线粒体中。与基质蛋白不同，许多膜间空间（IMS）的蛋白质缺乏前导序列，它们通过线粒体的二硫键中继物的氧化驱动反应进行输入。输入的多肽被位于 IMS 中的受体 Mia40 识别和氧化。Mia40 的再氧化由硫氧还蛋白 Erv1 和呼吸链协助完成。尽管在结构上没有关系，但线粒体的二硫键中继物在功能上类似于细菌周质的 Dsb（二硫键）系统，而 IMS 就是从 20 亿年前的这个区域衍生而来的。
