1. Interaction of nitric oxide with a functional model of cytochrome c oxidase
- Author
-
Collman, James P., Dey, Abhishek, Decreau, Richard A., Yang, Ying, Hosseini, Ali, Solomon, Edward I., and Eberspacher, Todd A.
- Subjects
Nitric oxide -- Properties ,Nitric oxide -- Control ,Cytochrome oxidase -- Properties ,Cytochrome c -- Properties ,Science and technology - Abstract
Cytochrome c oxidase (CcO) is a multimetallic enzyme that carries out the reduction of [O.sub.2] to [H.subq]O and is essential to respiration, providing the energy that powers all aerobic organisms by generating heat and forming ATP. The oxygen-binding heme [a.sub.3] should be subject to fatal inhibition by chemicals that could compete with [O.sub.2] binding. Near the CcO active site is another enzyme, NO synthase, which produces the gaseous hormone NO. NO can strongly bind to heme [a.sub.3], thus inhibiting respiration. However, this disaster does not occur. Using functional models for the CcO active site, we show how NO inhibition is avoided; in fact, it is found that NO can protect the respiratory enzyme from other inhibitors such as cyanide, a classic poison. amyl nitrite | cyanide poisoning | synthetic functional model | EPR
- Published
- 2008