Modification of pig kidney diamine oxidase with ethoxyformic anhydride and rose bengal: evidence for essential histidyl residue at the active site.
Purified diamine oxidase from pig kidney showed time dependent inactivation by ethoxyformic anhydride and photooxidation with Rose Bengal. Modification of histidine either by ethoxyformic anhydride or by Rose Bengal was the sole cause of enzyme inactivation. The inactivated enzyme showed no significant perturbation in structure. The protection against photooxidation of enzymatic activity and histidine residues by inhibitor (phenylenediamine hydrochloride) and substrate (putrescine) protected the photooxidation of two histidyl residues. However, kinetic analysis of photooxidation of histidyl residues and inactivation of the enzyme conclusively suggested the involvement of one histidyl residue, which seems to be located at the active site of diamine oxidase.
Shah
M A
MA
Department of Biochemistry, Faculty of Medicine, A.M.U. Aligarh, India.
Ali
R
R
D006631:Amine Oxidase (Copper-Containing) / Q000037:antagonists & inhibitors* / Q000737:chemistry; D000818:Animals; D001665:Binding Sites; D004047:Diethyl Pyrocarbonate / Q000494:pharmacology*; D006639:Histidine / Q000032:analysis*; D019811:Hydroxylamine; D006898:Hydroxylamines / Q000494:pharmacology; D007668:Kidney / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D010083:Oxidants, Photochemical / Q000737:chemistry / Q000494:pharmacology; D011700:Putrescine / Q000737:chemistry; D012395:Rose Bengal / Q000494:pharmacology; D013050:Spectrometry, Fluorescence; D013379:Substrate Specificity; D013552:Swine
D006898:Hydroxylamines; D010083:Oxidants, Photochemical; D012395:Rose Bengal; D019811:Hydroxylamine; D006639:Histidine; D006631:Amine Oxidase (Copper-Containing); D004047:Diethyl Pyrocarbonate; D011700:Putrescine