[Synthesis of multiple forms of brain cholinesterases]

Highly purified multiple forms of brain cholinesterase were isolated by a new method. Eight forms were identified as acetyl cholinesterases, seven forms--as butyryl cholinesterases, four forms--as mixed acetyl- and butyryl cholinesterases and four forms--as aliesterases. Biosynthesis of multiple forms of brain cholinesterase was monitored by following incorporation of 14C-glycine into the purified fractions. Cats were killed at different periods (3 hrs, 3,6 and 9 days) after intoxication with isopropyl hydroxymethyl fluorophosphate. The restoration of the enzymatic activity after the inhibition did not correspond to the incorporation of the labelled amino acid into the enzyme protein. There was a transcient increase in the incorporation of the label after an increase in acetylcholine concentration.