Nanosecond photoreduction of inducible nitric oxide synthase by a Ru-diimine electron tunneling wire bound distant from the active site.
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ABSTRACT:
SUBMITTER: Whited CA
PROVIDER: S-EPMC2700734 | biostudies-literature | 2009 Jun
REPOSITORIES: biostudies-literature
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Nanosecond photoreduction of inducible nitric oxide synthase by a Ru-diimine electron tunneling wire bound distant from the active site.
Whited Charlotte A CA Belliston-Bittner Wendy W Dunn Alexander R AR Winkler Jay R JR Gray Harry B HB
Journal of inorganic biochemistry 20090417 6
A Ru-diimine wire, [(4,4',5,5'-tetramethylbipyridine)2Ru(F9bp)]2+ (tmRu-F9bp, where F9bp is 4-methyl-4'-methylperfluorobiphenylbipyridine), binds tightly to the oxidase domain of inducible nitric oxide synthase (iNOSoxy). The binding of tmRu-F9bp is independent of tetrahydrobiopterin, arginine, and imidazole, indicating that the wire resides on the surface of the enzyme, distant from the active-site heme. Photoreduction of an imidazole-bound active-site heme iron in the enzyme-wire conjugate (k( ...[more]
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