Mitochondrial electron transport chain

Mitochondrial electron transport chainIllustration with English labellingSchematic of the mitochondrial electron transport chain with the different complexes (I, II, III und IV) and the ATP-synthase (complex V) in the inner membrane of the mitochondria.

Top row: Electron insertion through complex I (NADH-dehydrogenase) via oxidation of NADH to NAD+. The electrons are transported to complex III (cytochrome bc1) by coenzyme Q and then via Cytochrome c to complex IV (cytochrome c oxidase) where they reduce oxygen (O2) to water.

Bottom row: Electron insertion through complex II (succinate dehydrogenase) via oxidation of succinate to fumarate. Then the electrons take the same path thorugh coenzyme Q, complex III and cytochrome c to comlex IV to water.

author: Klaus Hoffmeier via wikipedia