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Catalytic reduction of O2 by cytochrome C using a synthetic model of cytochrome C oxidase.

ABSTRACT: Cytochrome c oxidase (CcO) catalyzes the four-electron reduction of oxygen to water, the one-electron reductant Cytochrome c (Cytc) being the source of electrons. Recently we reported a functional model of CcO that electrochemically catalyzes the four-electron reduction of O(2) to H(2)O (Collman et al. Science 2007, 315, 1565). The current paper shows that the same functional CcO model catalyzes the four-electron reduction of O(2) using the actual biological reductant Cytc in a homogeneous solution. Both single and steady-state turnover kinetics studies indicate that O(2) binding is rate-determining and that O-O bond cleavage and electron transfer from reduced Cytc to the oxidized model complex are relatively fast.

SUBMITTER: Collman JP

PROVIDER: S-EPMC2743311 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Catalytic reduction of O2 by cytochrome C using a synthetic model of cytochrome C oxidase.

Collman James P JP Ghosh Somdatta S Dey Abhishek A Decréau Richard A RA Yang Ying Y

Journal of the American Chemical Society 20090401 14

Cytochrome c oxidase (CcO) catalyzes the four-electron reduction of oxygen to water, the one-electron reductant Cytochrome c (Cytc) being the source of electrons. Recently we reported a functional model of CcO that electrochemically catalyzes the four-electron reduction of O(2) to H(2)O (Collman et al. Science 2007, 315, 1565). The current paper shows that the same functional CcO model catalyzes the four-electron reduction of O(2) using the actual biological reductant Cytc in a homogeneous solut ...[more]

PMID: 19317484

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