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Updated: Aug 19, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Torpedo acetylcholinesterase is inactivated by thiol reagents
N Steinberg1, E Roth, I Silman
1Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Abstract:
A number of sulphydryl reagents inhibit AChE of Torpedo california with pseudo-first-order kinetics, and inhibition can be retarded by quaternary ligands which bind at either the catalytic or peripheral anionic binding sites. Colorimetric determination with one of the inhibitory sulphydryl agents, 5,5'-dithiobis (2-nitrobenzoic acid), reveals the presence of a single thiol group per catalytic subunit; our data thus suggest that inhibition is achieved by reaction with the single free sulphydryl group of Cys231.
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