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X-ray structure of the NO-bound Cu(B) in bovine cytochrome c oxidase.

ABSTRACT: The X-ray crystallographic structure of nitric oxide-treated bovine heart cytochrome c oxidase (CcO) in the fully reduced state has been determined at 50 K under light illumination. In this structure, nitric oxide (NO) is bound to the CcO oxygen-reduction site, which consists of haem and a Cu atom (the haem a(3)-Cu(B) site). Electron density for the NO molecule was observed close to Cu(B). The refined structure indicates that NO is bound to Cu(B) in a side-on manner.

SUBMITTER: Ohta K

PROVIDER: S-EPMC2833029 | biostudies-literature | 2010 Mar

REPOSITORIES: biostudies-literature

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X-ray structure of the NO-bound Cu(B) in bovine cytochrome c oxidase.

Ohta Kazuhiro K Muramoto Kazumasa K Shinzawa-Itoh Kyoko K Yamashita Eiki E Yoshikawa Shinya S Tsukihara Tomitake T

Acta crystallographica. Section F, Structural biology and crystallization communications 20100223 Pt 3

The X-ray crystallographic structure of nitric oxide-treated bovine heart cytochrome c oxidase (CcO) in the fully reduced state has been determined at 50 K under light illumination. In this structure, nitric oxide (NO) is bound to the CcO oxygen-reduction site, which consists of haem and a Cu atom (the haem a(3)-Cu(B) site). Electron density for the NO molecule was observed close to Cu(B). The refined structure indicates that NO is bound to Cu(B) in a side-on manner. ...[more]

PMID: 20208153

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