title: Heme environment in aldoxime dehydratase involved in carbon-nitrogen triple bond synthesis.
abstract: Resonance Raman spectra have been measured to characterize the heme environment in aldoxime dehydratase (OxdA), a novel hemoprotein, which catalyzes the dehydration of aldoxime into nitrile. The spectra showed that the ferric heme in the enzyme is six-coordinate low spin, whereas the ferrous heme is five-coordinate high spin. We assign a prominent vibration that occurs at 226 cm(-1) in the ferrous enzyme to the Fe-proximal histidine stretching vibration. In the CO-bound form of OxdA, the correlation between the Fe-CO stretching (512 cm(-1)) and C-O stretching (1950 cm(-1)) frequencies also supports our assignment of proximal histidine coordination.
authors.affiliation: Institute of Applied Biochemistry, The University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Oinuma
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: Michihiko
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D002244:Carbon / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry; D006418:Heme / Q000737:chemistry*; D006836:Hydro-Lyases / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D013059:Spectrum Analysis, Raman
chemical_list: D006418:Heme; D002244:Carbon; D002248:Carbon Monoxide; D006836:Hydro-Lyases; C412124:aldoxime dehydratase; D009584:Nitrogen