Electron transfer process in cytochrome oxidase after pulse radiolysis
نویسندگان
چکیده
منابع مشابه
Electron transfer in milk xanthine oxidase as studied by pulse radiolysis.
Electron transfer within milk xanthine oxidase has been examined by the technique of pulse radiolysis. Radiolytically generated N-methylnicotinamide radical or 5-deazalumiflavin radical has been used to rapidly and selectively introduce reducing equivalents into the enzyme so that subsequent equilibration among the four redox-active centers of the enzyme (a molybdenum center, two iron-sulfur ce...
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Cytochrome c oxidase mediates the final step of electron transfer reactions in the respiratory chain, catalyzing the transfer between cytochrome c and the molecular oxygen and concomitantly pumping protons across the inner mitochondrial membrane. We investigate the electron transfer reactions in cytochrome c oxidase, particularly the control of the effective electronic coupling by the nuclear t...
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Cytochrome oxidase catalyzes the four-electron reduction of O2 to water and conserves the substantial free energy of the reaction in the form of a protonmotive force. For each electron, two full charges are translocated across the membrane, resulting in a voltage. One of the mechanisms to generate the charge separation in cytochrome oxidase is via a proton pump. A single reaction cycle can be m...
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Electron transfer within rat neuronal nitric-oxide synthase (nNOS) was investigated by pulse radiolysis. Radiolytically generated 1-methyl-3-carbamoyl pyridinium (MCP) radical was found to react predominantly with the heme of the enzyme with a second-order rate constant for heme reduction of 3 x 10(8) m(-1) s(-1). In the calmodulin (CaM)-bound enzyme a subsequent first-order phase was observed ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1989
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(18)83138-6