title: Inactivation of leucine aminotransferase with diethylpyrocarbonate and rose bengal: evidence for an active site histidine residue.
abstract: Modification of leucine aminotransferase by diethylpyrocarbonate or rose bengal-sensitized photo-oxidation caused rapid inactivation of the enzyme. The inactivation of leucine aminotransferase depended on the concentration of the reagent, the time of incubation and exhibited pseudo-first order kinetics. Rose bengal-sensitized photo-oxidation was maximum at pH 6.5 and 9. Substrates leucine and alpha-ketoglutarate protected the enzyme against inactivation by these reagents, thus suggesting participation of histidine residue at the substrate binding site.
authors.forename: U
authors.initials: U
authors.lastname: Pathre
authors.forename: A K
authors.initials: AK
authors.lastname: Singh
authors.forename: P V
authors.initials: PV
authors.lastname: Sane
mesh_terms: D001665:Binding Sites; D004047:Diethyl Pyrocarbonate; D006639:Histidine / Q000502:physiology; D007202:Indicators and Reagents; D051276:Leucine Transaminase; D010944:Plants / Q000201:enzymology*; D012395:Rose Bengal; D000637:Transaminases / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D007202:Indicators and Reagents; D012395:Rose Bengal; D006639:Histidine; D000637:Transaminases; D051276:Leucine Transaminase; D004047:Diethyl Pyrocarbonate