Dudkina Natalia V, Eubel Holger, Keegstra Wilko, Boekema Egbert J, Braun Hans-Peter
Department of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Proc Natl Acad Sci U S A. 2005 Mar 1;102(9):3225-9. doi: 10.1073/pnas.0408870102. Epub 2005 Feb 15.
Mitochondria are central to the efficient provision of energy for eukaryotic cells. The oxidative-phosphorylation system of mitochondria consists of a series of five major membrane complexes: NADH-ubiquinone oxidoreductase (commonly known as complex I), succinate-ubiquinone oxidoreductase (complex II), ubiquinol-cytochrome c oxidoreductase (cytochrome bc1 complex or complex III), cytochrome c-O2 oxidoreductase (complex IV), and F1F0-ATP synthase (complex V). Several lines of evidence have recently suggested that complexes I and III-V might interact to form supercomplexes. However, because of their fragility, the structures of these supercomplexes are still unknown. A stable supercomplex consisting of complex I and dimeric complex III was purified from plant mitochondria. Structural characterization by single-particle EM indicates a specific type of interaction between monomeric complex I and dimeric complex III in a 1:1 ratio. We present a model for how complexes I and III are spatially organized within the I+III2 supercomplex.
线粒体对于真核细胞高效提供能量至关重要。线粒体的氧化磷酸化系统由一系列五个主要膜复合物组成：NADH-泛醌氧化还原酶（通常称为复合物I）、琥珀酸-泛醌氧化还原酶（复合物II）、泛醇-细胞色素c氧化还原酶（细胞色素bc1复合物或复合物III）、细胞色素c-O2氧化还原酶（复合物IV）和F1F0-ATP合酶（复合物V）。最近有几条证据表明复合物I和III-V可能相互作用形成超复合物。然而，由于它们的脆弱性，这些超复合物的结构仍然未知。从植物线粒体中纯化出了一种由复合物I和二聚体复合物III组成的稳定超复合物。单颗粒电子显微镜的结构表征表明单体复合物I和二聚体复合物III以1:1的比例存在特定类型的相互作用。我们提出了一个关于复合物I和III在I+III2超复合物中如何进行空间组织的模型。
