Biomaterial Database

An improved spectrophotometric assay for histamine and diamine oxidase (DAO) activity. 1985

P Stoner

Diamine oxidase or its substrates can be measured using a coupled reaction with peroxidase and the chromogen 3-methyl-2-benzothiazolone hydrazone (MBTH) with an appropriate acceptor such as 3-(dimethylamino)benzoic acid (DMAB). This method provides a more rapid and sensitive method of measuring histamine than current colorimetric assays; using this system, histamine was quantitated at concentrations of 10 to 400 mumol/l. The Km of DAO was determined to be 2.9 X 10(-5) M, a lower value than previously reported.

UI	MeSH Term	Description	Entries
D002863	Chromogenic Compounds	Colorless, endogenous or exogenous pigment precursors that may be transformed by biological mechanisms into colored compounds; used in biochemical assays and in diagnosis as indicators, especially in the form of enzyme substrates. Synonym: chromogens (not to be confused with pigment-synthesizing bacteria also called chromogens).	Chromogenic Compound,Chromogenic Substrate,Chromogenic Substrates,Compound, Chromogenic,Compounds, Chromogenic,Substrate, Chromogenic,Substrates, Chromogenic
D006631	Amine Oxidase (Copper-Containing)	A group of enzymes including those oxidizing primary monoamines, diamines, and histamine. They are copper proteins, and, as their action depends on a carbonyl group, they are sensitive to inhibition by semicarbazide.	Diamine Oxidase,Histaminase,Amine Oxidase, Copper-Containing,Copper Amine Oxidase,Diaminobenzidine Oxidase,Semicarbazide-Sensitive Amine Oxidase,Xylylene Diamine Oxidase,Amine Oxidase, Copper,Amine Oxidase, Copper Containing,Amine Oxidase, Semicarbazide-Sensitive,Copper-Containing Amine Oxidase,Diamine Oxidase, Xylylene,Oxidase, Copper Amine,Oxidase, Copper-Containing Amine,Oxidase, Diamine,Oxidase, Diaminobenzidine,Oxidase, Semicarbazide-Sensitive Amine,Oxidase, Xylylene Diamine,Semicarbazide Sensitive Amine Oxidase
D006632	Histamine	An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.	Ceplene,Histamine Dihydrochloride,Histamine Hydrochloride,Peremin
D006835	Hydrazones	Compounds of the general formula R:N.NR2, as resulting from the action of hydrazines with aldehydes or ketones. (Grant & Hackh's Chemical Dictionary, 5th ed)	Hydrazone
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D013053	Spectrophotometry	The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
D013844	Thiazoles	Heterocyclic compounds where the ring system is composed of three CARBON atoms, a SULFUR and NITROGEN atoms.	Thiazole
D052160	Benzothiazoles	Compounds with a benzene ring fused to a thiazole ring.