Ubiquinone |
Synonyms: Coenzyme Q10, Q10
Ubiquinione or Q10 is a fat-soluble, electron-transporting co-enzyme found in the electron-transport chain in mitochondria. Ubiquinone is a quinone which cyclically can change from an oxidized to a reduced form. The long isoprenoid chain of ubiquinone renders the molecule so nonpolar that it readily resides in the nonpolar phase of the mitochondrial lipid membrane. Several ubiquinones is known where the only difference is the lenght of the isoprenoid side chain. In animal tissues the length is 10 isoprene units therefore the shorthand notation: Q10. In plants the plastoquinines is found in the photosynthetic electron-transport chain where they perform a similar action as the Q10's in mitochondria. Ubiquinone has an absorption band at 270-290 nm which disappears when the molecule is reduced to its quinol-form. In the laboratory this change is used to follow the cyclic oxidation and reduction of ubiquinone.
Ubiquinone
3D structure of ubiquinone
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