title: [Synthesis of tritium-labeled N,N-dimethyl-2-phenylaziridinium and its reaction with acetylcholinesterase].
abstract: The synthesis of tritium-labeled N,N-demethyl-2-phenylaziridinium has been described. The specific radioactivity of the product obtained was 1,06 TBq/mmole. Kinetics of incorporation of this radioactive label into acetylcholinesterase of cobra venom (Naja naja oxiana) has been studied at 1,05 mM ligand concentration (25 degrees C, pH 7,50. 0,15 M phosphate buffer). Under these conditions two molecules of the radioactive label have been found to react with the enzyme. One molecule incorporates fast with half-life of 4,8 min, not affecting the enzymatic activity. Incorporation of the second label is a slow reaction with half-life of 6 hr and leads to complete inactivation of acetylcholinesterase. Molecular mass of the modified enzyme is 63 +/- 4 kDa and coincides with that of native one.
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D001388:Aziridines / Q000138:chemical synthesis* / Q000378:metabolism / Q000494:pharmacology; D001389:Azirines / Q000138:chemical synthesis*; D001665:Binding Sites; D055598:Chemical Phenomena; D002621:Chemistry; D002800:Cholinesterase Inhibitors / Q000138:chemical synthesis* / Q000378:metabolism; D003039:Cobra Neurotoxin Proteins; D007700:Kinetics; D008970:Molecular Weight; D014316:Tritium
chemical_list: D001388:Aziridines; D001389:Azirines; D002800:Cholinesterase Inhibitors; D003039:Cobra Neurotoxin Proteins; D014316:Tritium; C001054:N,N-dimethyl-2-phenylaziridinium; D000110:Acetylcholinesterase
vernacular_title: Sintez mechenogo tritiem N,N-dimetil-2-fenilaziridiniia i ego reaktsiia s atsetilkholinésterazoĭ.