Thermodynamic redox properties governing the half-reduction characteristics of histamine dehydrogenase from Nocardioides simplex.

Content Provider	Semantic Scholar
Author	Tsutsumi, Maiko Fujieda, Nobutaka Tsujimura, Seiya Shirai, Osamu Kano, Kenji
Copyright Year	2008
Abstract	Histamine dehydrogenase from Nocardioides simplex is a homodimer and belongs to the family of iron-sulfur flavoproteins having one [4Fe-4S] cluster and one 6-S-cysteinyl FMN per monomer. In the reductive titration with histamine, two-electron reduction occurred per monomer at pH<9, while single-electron reduction proceeded at pH>9. The substrate-reduced histamine dehydrogenase yielded an electron paramagnetic resonance spectral signal assigned to the flavin semiquinone. The signal intensity increased with pH up to pH 9 and reached a maximum at pH>9. These unique features are explained in terms of the redox potential of the cofactors, where the redox potential was evaluated over a pH range from 7 to 10 by using a spectroelectrochemical titration method for the flavin and cyclic voltammetry for the [4Fe-4S] cluster. The bell-type pH dependence of the enzymatic activity is also discussed in terms of the pH dependence of the centers' redox potential.
Starting Page	5155
Ending Page	5167
Page Count	13
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://www.jstage.jst.go.jp/article/bbb/72/3/72_70665/_pdf
PubMed reference number	18323648v1
Volume Number	72
Issue Number	3
Journal	Bioscience, biotechnology, and biochemistry
Language	English
Access Restriction	Open
Subject Keyword	4,6-dinitro-o-cresol Electron Spin Resonance Spectroscopy Flavin Mononucleotide Flavin-Adenine Dinucleotide Flavins Flavoproteins Histamine Nocardioides PersonNameUse - assigned Thermodynamics Titration Method chemical cofactor monomer semiquinone
Content Type	Text
Resource Type	Article