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Crystallographic and single-crystal spectral analysis of the peroxidase ferryl intermediate.

ABSTRACT: The ferryl [Fe(IV)O] intermediate is important in many heme enzymes, and thus, the precise nature of the Fe(IV)-O bond is critical in understanding enzymatic mechanisms. The 1.40 A crystal structure of cytochrome c peroxidase Compound I has been determined as a function of X-ray dose while the visible spectrum was being monitored. The Fe-O bond increases in length from 1.73 A in the low-X-ray dose structure to 1.90 A in the high-dose structure. The low-dose structure correlates well with an Fe(IV) horizontal lineO bond, while we postulate that the high-dose structure is the cryo-trapped Fe(III)-OH species previously thought to be an Fe(IV)-OH species.

SUBMITTER: Meharenna YT

PROVIDER: S-EPMC3202969 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Crystallographic and single-crystal spectral analysis of the peroxidase ferryl intermediate.

Meharenna Yergalem T YT Doukov Tzanko T Li Huiying H Soltis S Michael SM Poulos Thomas L TL

Biochemistry 20100401 14

The ferryl [Fe(IV)O] intermediate is important in many heme enzymes, and thus, the precise nature of the Fe(IV)-O bond is critical in understanding enzymatic mechanisms. The 1.40 A crystal structure of cytochrome c peroxidase Compound I has been determined as a function of X-ray dose while the visible spectrum was being monitored. The Fe-O bond increases in length from 1.73 A in the low-X-ray dose structure to 1.90 A in the high-dose structure. The low-dose structure correlates well with an Fe(I ...[more]

PMID: 20230048

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