Stopped-flow spectrophotometric and resonance Raman analyses of aldoxime dehydratase involved in carbon-nitrogen triple bond synthesis.
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.
Oinuma
Ken-Ichi
K
Institute of Applied Biochemistry and Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Kumita
Hideyuki
H
Ohta
Takehiro
T
Konishi
Kazunobu
K
Hashimoto
Yoshiteru
Y
Higashibata
Hiroki
H
Kitagawa
Teizo
T
Shiro
Yoshitsugu
Y
Kobayashi
Michihiko
M
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
D006639:Histidine; D002244:Carbon; D006836:Hydro-Lyases; C412124:aldoxime dehydratase; D009584:Nitrogen