Abstract
The second segment of the respiratory chain of mitochondria (b-c1 complex, complex III or ubiquinol-cytochrome c reductase, E.C. 1.10.2.2) is an oligomeric integral protein of approx. 240 kDa in a monomeric form, which catalyses the transfer of electrons from ubiquinol or synthetic analogs to ferricytochrome c. The flow of reducing equivalents from dehydrogenase or quinols to cytochrome c, along the b-c1 complex, results in the effective translocation of two protons from the matrix space (Negative phase) to the outer space (Positive phase); two additional protons, deriving from the scalar oxidation of a hydrogen donor, are released in the P phase, thus giving an overall H+/2e− stoicheiometry of 4.
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© 1989 Plenum Press, New York
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Lorusso, M., Cocco, T., Boffoli, D. (1989). The Mitochondrial b-c1 Complex: Polypeptide Composition and Enzymatic Activities. In: Tager, J.M., Azzi, A., Papa, S., Guerrieri, F. (eds) Organelles in Eukaryotic Cells. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-0545-3_15
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DOI: https://doi.org/10.1007/978-1-4613-0545-3_15
Publisher Name: Springer, Boston, MA
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