Carbon monoxide binding to pentacoordinate mercaptide-heme complexes: kinetic study on models for cytochrome P-450.
- 1 October 1976
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 73 (10), 3338-3342
- https://doi.org/10.1073/pnas.73.10.3338
Abstract
Mercaptide anions form exclusively pentacoordinate heme complexes [RS-.cntdot.heme] in polar and nonpolar solution over a wide range of mercaptide concentration. These complexes have a Soret peak at 408 nm and a formation constant of .apprx. 2.5 .times. 104 M-1, and combine with CO to give a CO.cntdot.cytochrome P-450 type spectrum. Kinetics of CO binding to mercaptide.cntdot.heme complexes [RS-.cntdot.heme] were studied by the flash photolysis method. Characteristic constants for this reaction suggest close similarities between [CH3-(CH2)3-S-.cntdot.heme] and cytochrome P-450. The reaction of alkoxide anion with heme was also examined but no evidence was found for the existence of the [RO-.cntdot.heme.cntdot.CO] species.This publication has 25 references indexed in Scilit:
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