Arnold I, Pfeiffer K, Neupert W, Stuart R A, Schägger H
Institut für Physiologische Chemie der Universität München, D-80336 München, Germany.
EMBO J. 1998 Dec 15;17(24):7170-8. doi: 10.1093/emboj/17.24.7170.
Using the technique of blue native gel electrophoresis, the oligomeric state of the yeast mitochondrial F1F0-ATP synthase was analysed. Solubilization of mitochondrial membranes with low detergent to protein ratios led to the identification of the dimeric state of the ATP synthase. Analysis of the subunit composition of the dimer, in comparison with the monomer, revealed the presence of three additional small proteins. These dimer-specific subunits of the ATP synthase were identified as the recently described subunit e/Tim11 (Su e/Tim11), the putative subunit g homolog (Su g) and a new component termed subunit k (Su k). Although, as shown here, these three proteins are not required for the formation of enzymatically active ATP synthase, Su e/Tim11 and Su g are essential for the formation of the dimeric state. Su e/Tim11 appears to play a central role in this dimerization process. The dimer-specific subunits are associated with the membrane bound F0-sector. The F0-sector may thereby be involved in the dimerization of two monomeric F1F0-ATP synthase complexes. We speculate that the F1F0-ATP synthase of yeast, like the other complexes of oxidative phosphorylation, form supracomplexes to optimize transduction of energy and to enhance the stability of the complex in the membrane.
运用蓝色非变性凝胶电泳技术，对酵母线粒体F1F0 - ATP合酶的寡聚状态进行了分析。以低去污剂与蛋白质比例溶解线粒体膜，从而鉴定出ATP合酶的二聚体状态。与单体相比，对二聚体的亚基组成进行分析，发现存在另外三种小蛋白质。ATP合酶的这些二聚体特异性亚基被鉴定为最近描述的亚基e/Tim11（亚基e/Tim11）、假定的亚基g同源物（亚基g）和一种新成分，称为亚基k（亚基k）。尽管如此处所示，这三种蛋白质并非形成具有酶活性的ATP合酶所必需，但亚基e/Tim11和亚基g对于二聚体状态的形成至关重要。亚基e/Tim11似乎在这个二聚化过程中发挥核心作用。二聚体特异性亚基与膜结合的F0部分相关联。F0部分可能因此参与两个单体F1F0 - ATP合酶复合物的二聚化。我们推测，酵母的F1F0 - ATP合酶与氧化磷酸化的其他复合物一样，形成超复合物以优化能量转导并增强复合物在膜中的稳定性。
