The flexible chain: regulation of structure and activity of ETC complexes defines rate of ATP synthesis and sites of superoxide generation.

This review highlights current insights into the regulation of the mitochondrial respiratory chain (electron transport chain, ETC) activity. The regulation of ETC properties optimizes ATP synthesis and controls the generation of the superoxide anion radical (O ) which can be converted into other reactive oxygen species (ROS) playing a dual role by initiating signaling cascades or contributing to oxidative stress. We examine how ETC activity is influenced by the structure and conformation of its complexes, their allosteric or post-translational modifications, and their interactions with membrane lipids.