Identification by gas chromatography-mass spectrometry of an adduct between pure pig plasma benzylamine oxidase and the inhibitor 3,5-diethoxy-4-aminomethylpyridine.
3,5-Diethoxy-4-aminomethylpyridine (B24) interacts with pure pig plasma benzylamine oxidase (BAO), giving a Schiff base with the carbonyl active site. This Schiff base was reduced, isolated by chemical hydrolysis of the enzyme, purified by HPLC and identified by gas chromatography-mass spectrometry (GC-MS) after derivatization. The isolated B24 adduct had the same absorption spectrum, retention time on HPLC and GC and the same mass spectrum as B24-pyridoxamine. B24, which is a reversible enzyme inhibitor, is also a weak substrate and competes with benzylamine, which is the best substrate, for the active site. These results further indicate the presence of pyridoxal-phosphate covalently linked to the pig plasma benzylamine oxidase and involved in the active site of this enzyme.
Buffoni
F
F
Department of Pharmacology of the University of Florence, Italy.
Moneti
G
G
Pieraccini
G
G
Bertini
V
V
D000818:Animals; D001595:Benzylamine Oxidase / Q000037:antagonists & inhibitors / Q000097:blood / Q000378:metabolism*; D001596:Benzylamines / Q000378:metabolism; D001665:Binding Sites; D001667:Binding, Competitive; D002851:Chromatography, High Pressure Liquid; D008401:Gas Chromatography-Mass Spectrometry; D008956:Models, Chemical; D011485:Protein Binding; D011725:Pyridines / Q000737:chemistry / Q000378:metabolism*; D011732:Pyridoxal Phosphate / Q000378:metabolism*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013552:Swine
C094718:3,5-diethoxy-4-aminomethylpyridine; D001596:Benzylamines; D011725:Pyridines; D011732:Pyridoxal Phosphate; D001595:Benzylamine Oxidase