Formation of Reactive Oxygen Species in Mitochondria
Living organisms obtain energy from the oxidation of various biomolecules, including carbohydrates, lipids and the carbon skeletons of amino acids. Under aerobic conditions, the reducing coenzymes produced during these reactions are re-oxidized in the electron transport chain, transferring electrons to molecular oxygen (E°= +800 mV) through a series of electron carriers in the respiratory chain. This electrochemical energy is converted into a proton gradient which, in turn, operates a rotor-type enzymatic complex (ATP synthase or Complex V), inducing conformational changes which cause ADP and inorganic phosphate to bind to the active site and ATP to be released (Noji and Yoshida 2001).
KeywordsReactive Oxygen Species Respiratory Chain Reactive Oxygen Species Formation Heart Mitochondrion Phospholipid Hydroperoxide Glutathione Peroxidase
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