Eco-Bio, Instituto de Investigação Científica Tropical, Av. da República, Oeiras, Portugal.
Biochimie. 2011 Mar;93(3):418-25. doi: 10.1016/j.biochi.2010.10.014. Epub 2010 Oct 30.
The organization of respiratory chain complexes in supercomplexes has been shown in the mitochondria of several eukaryotes and in the cell membranes of some bacteria. These supercomplexes are suggested to be important for oxidative phosphorylation efficiency and to prevent the formation of reactive oxygen species. Here we describe, for the first time, the identification of supramolecular organizations in the aerobic respiratory chain of Escherichia coli, including a trimer of succinate dehydrogenase. Furthermore, two heterooligomerizations have been shown: one resulting from the association of the NADH:quinone oxidoreductases NDH-1 and NDH-2, and another composed by the cytochrome bo(3) quinol:oxygen reductase, cytochrome bd quinol:oxygen reductase and formate dehydrogenase (fdo). These results are supported by blue native-electrophoresis, mass spectrometry and kinetic data of wild type and mutant E . coli strains.
呼吸链复合物在超复合物中的组织形式已在几种真核生物的线粒体和一些细菌的细胞膜中得到证实。这些超复合物被认为对氧化磷酸化效率很重要，并能防止活性氧的形成。在这里，我们首次描述了好氧呼吸链在大肠杆菌中的超分子结构的鉴定，包括琥珀酸脱氢酶的三聚体。此外，还显示了两种异源寡聚化：一种是由 NADH：醌氧化还原酶 NDH-1 和 NDH-2 组成，另一种是由细胞色素 bo(3)醌：氧还原酶、细胞色素 bd 醌：氧还原酶和甲酸脱氢酶（fdo）组成。这些结果得到了野生型和突变型大肠杆菌菌株的蓝色非变性电泳、质谱和动力学数据的支持。
