Model for cytochrome oxidase
- Rice Univ., Houston, TX
A model is proposed for the active center of cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) in which cytochrome a is a low-spin ferrihemoprotein and cytochrome a/sub 3/ is a high-spin ferrihemoprotein antiferromagnetically coupled to one of the two Cu/sup 2 +/ ions present in the enzyme. It is further proposed that reduction is accompanied by a conformational change in the enzyme thus exposing the sixth coordination site of cytochrome a/sub 3/ to ligands. With this model it is possible to account for a variety of outstanding observations including the results of magnetic circular dichroism, Mossbauer, and electron paramagnetic resonance spectroscopies, as well as magnetic susceptibility measurements.
- OSTI ID:
- 7179266
- Journal Information:
- Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 73:7
- Country of Publication:
- United States
- Language:
- English
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