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Updated: Aug 11, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Alkylation of acetylcholinesterase anionic centre with aziridinium ion accelerates the enzyme acylation step
Abstract:
Affinity labelling of acetylcholinesterase (EC 3.1.1.7, acetylcholine acetylhydrolase) anionic centre with N,N-dimethyl-2-phenylaziridinium ion accelerates the hydrolysis of non-ionic acetic esters by increasing the rate of the enzyme acylation step at least 500-times while the rate of the deacylation step remains unchanged. Simultaneously, at least a 10-fold decrease of the substrate binding affinity takes place. The acceleration phenomenon can be explained by the "induced fit" mechanism as the binding of the cationic label to the enzyme anionic site brings the esteratic centre into conformation which provides extra stabilization for the transition state of the enzyme acylation reaction, probably by a more close structural fit between the substrate molecule and the enzyme active centre.
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