On the Origin of the Low-Spin Character of Cytochrome P450cam in the Resting State-Investigations of Enzyme Models with Pulse EPR and ENDOR Spectroscopy

Hamed Aissaoui; Rainer Bachmann; Arthur Schweiger; Wolf-Dietrich Woggon

doi:10.1002/(SICI)1521-3773(19981116)37:21<2998::AID-ANIE2998>3.0.CO;2-P

On the Origin of the Low-Spin Character of Cytochrome P450_cam in the Resting State-Investigations of Enzyme Models with Pulse EPR and ENDOR Spectroscopy

Angew Chem Int Ed Engl. 1998 Nov 16;37(21):2998-3002. doi: 10.1002/(SICI)1521-3773(19981116)37:21<2998::AID-ANIE2998>3.0.CO;2-P.

Authors

Hamed Aissaoui¹, Rainer Bachmann², Arthur Schweiger², Wolf-Dietrich Woggon¹

Affiliations

¹ Institut für Organische Chemie der Universität, St.-Johanns-Ring 19, CH-4056 Basel (Switzerland), Fax: (+41) 61-267-11-02.
² Laboratorium für Physikalische Chemie, Eidgenössische Technische Hochschule, CH-8092 Zürich (Switzerland).

Abstract

The P450 enzyme model 1 is a high-spin system. EPR and ENDOR spectra reveal the coordination of water to the Fe^III center. This is the first experimental proof that coordination of water is not the single determining factor in the stabilization of the low-spin character of the cytochrome P450 resting state.

Keywords: Cytochrome P450; EPR spectroscopy; Enzyme mimetics; Porphyrinoids.