title: Probing the heme-thiolate oxygenase domain of inducible nitric oxide synthase with Ru(II) and Re(I) electron tunneling wires.
abstract: Nitric oxide synthase (NOS) catalyzes the production of nitric oxide from L-arginine and dioxygen at a thiolate-ligated heme active site. Although many of the reaction intermediates are as yet unidentified, it is well established that the catalytic cycle begins with substrate binding and rate-limiting electron transfer to the heme. Here we show that Ru(II)-diimine and Re(I)-diimine electron tunneling wires trigger nanosecond photoreduction of the active-site heme in the enzyme. Very rapid generation of a reduced thiolate-ligated heme opens the way for direct observation of short-lived intermediates in the NOS reaction cycle.
authors.affiliation: Beckman Institute, California Institute of Technology, Pasadena, 91125, USA.
authors.forename: Charlotte A
authors.initials: CA
authors.lastname: Whited
authors.forename: Wendy
authors.initials: W
authors.lastname: Belliston-Bittner
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Dunn
authors.forename: Jay R
authors.initials: JR
authors.lastname: Winkler
authors.forename: Harry B
authors.initials: HB
authors.lastname: Gray