title: Stopped-flow spectrophotometric and resonance Raman analyses of aldoxime dehydratase involved in carbon-nitrogen triple bond synthesis.
abstract: On stopped-flow analysis of aliphatic aldoxime dehydratase (OxdA), a novel hemoprotein, a spectrum derived from a reaction intermediate was detected on mixing ferrous OxdA with butyraldoxime; it gradually changed into that of ferrous OxdA with an isosbestic point at 421 nm. The spectral change on the addition of butyraldoxime to the ferrous H320A mutant showed the formation of a substrate-coordinated mutant, the absorption spectrum of which closely resembled that of the above intermediate. These observations and the resonance Raman investigation revealed that the substrate actually binds to the heme in OxdA, forming a hexa-coordinate low-spin heme.
authors.affiliation: Institute of Applied Biochemistry and Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Oinuma
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kumita
authors.forename: Takehiro
authors.initials: T
authors.lastname: Ohta
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Konishi
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Hashimoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Higashibata
authors.forename: Teizo
authors.initials: T
authors.lastname: Kitagawa
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Shiro
authors.forename: Michihiko
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D006639:Histidine / Q000235:genetics / Q000378:metabolism; D006836:Hydro-Lyases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D015394:Molecular Structure; D009154:Mutation / Q000235:genetics; D009584:Nitrogen / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*; D013059:Spectrum Analysis, Raman
chemical_list: D006639:Histidine; D002244:Carbon; D006836:Hydro-Lyases; C412124:aldoxime dehydratase; D009584:Nitrogen