title: X-ray absorption spectroscopy of chloroperoxidase compound I: Insight into the reactive intermediate of P450 chemistry.
abstract: We report the structural characterization of a thiolate-ligated ferryl radical. Using x-ray absorption spectroscopy, we examined chloroperoxidase (CPO) compound I (CPO-I). Our results indicate that CPO-I is an authentic ferryl species with an Fe-O bond of 1.65 A. Axial-ligand interactions result in a remarkably long 2.48-A Fe-S bond. Analogous forms of cytochrome P450 and CPO have been shown to possess virtually identical coordination environments. Thus, it seems likely that our findings provide a good structural description of the elusive P450-I.
authors.affiliation: Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Kari L
authors.initials: KL
authors.lastname: Stone
authors.forename: Rachel K
authors.initials: RK
authors.lastname: Behan
authors.forename: Michael T
authors.initials: MT
authors.lastname: Green
mesh_terms: D002711:Chloride Peroxidase / Q000737:chemistry*; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry*; D011487:Protein Conformation; D013057:Spectrum Analysis; D014965:X-Rays
chemical_list: D003577:Cytochrome P-450 Enzyme System; D002711:Chloride Peroxidase