Copyright information:Taken from "Mitochondrial Oxidative Damage in Aging and Alzheimer's Disease: Implications for Mitochondrially Targeted Antioxidant Therapeutics"Journal of Biomedicine and Biotechnology 2006;2006():-.Published online 11 Apr 2006PMCID:PMC1559913. In the respiratory chain, complexes 1 and 3 leak electrons to oxygen, producing primarily superoxide radicals (or ). The are dismutated by manganese superoxide dismutase to generate and oxygen. Complex 1 generates only toward the matrix. Complex 3, on the other hand, generates toward both the intermembrane space and the matrix. The components of tricarboxylic acid, including α-ketoglutarate dehydrogenase, also generate in the matrix. Free radicals are generated in the outer mitochondrial membrane (monoamine oxidase) and catalyze the oxidative deamination of primary aromatic amines, leading to the generation of .