The proton-translocating NADH-quinone oxidoreductase in the respiratory chain: The secret unlocked
The proton-translocating NADH-quinone oxidoreductase in the respiratory chain: The secret unlocked
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DOI：
10.1021/bi027158b
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发表时间：
2003-03-04
期刊：
影响因子：
2.9
通讯作者：
Matsuno-Yagi, A
中科院分区：
文献类型：
--
作者：
Yagi, T;Matsuno-Yagi, A
哺乳动物线粒体的呼吸链由四种酶复合物组成，如图1所示。这些复合物都位于哺乳动物的线粒体内膜中，被称为质子转运NADH-醌氧化还原酶（复合物I）、琥珀酸-醌氧化还原酶（复合物II）、bc 1复合物（复合物III）和细胞色素c氧化酶（复合物IV）。复合物I由至少46个不同的亚基（1）组成，总分子量约为1 MDa。这种酶复合物跨越线粒体内膜，带有一个非共价结合的FMN和八个铁硫簇（2）。它将质子从膜的基质侧转移到细胞质侧，产生穿过线粒体内膜的质子梯度。由于复合物I能够与底物的氧化一起泵送质子，因此它构成了氧化磷酸化系统的能量偶联位点1。除了存在于哺乳动物线粒体中，复合物I也存在于植物和真菌线粒体中
The respiratory chain of mammalian mitochondria is composed of four enzyme complexes as depicted in Figure 1. These complexes, which are all located in the mammalian inner-mitochondrial membrane, are referred to as the protontranslocating NADH-quinone oxidoreductase (complex I), 1 the succinate-quinone oxidoreductase (complex II), the bc1 complex (complex III), and cyt c oxidase (complex IV). Complex I is composed of at least 46 different subunits (1) with a total molecular mass of approximately 1 MDa. This enzyme complex, which spans the inner-mitochondrial membrane, bears one noncovalently bound FMN and eight iron-sulfur clusters (2). It translocates protons from the matrix side of the membrane to the cytoplasmic side, generating a proton gradient across the inner-mitochondrial membrane. Because of its ability to pump protons in concert with oxidation of a substrate, complex I constitutes the energy coupling site 1 of the oxidative phosphorylation system. In addition to being present in mammalian mitochondria, complex I is also present in plant and fungal mitochondria