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Updated: Aug 18, 2026

Direct Detection of the Acetate-forming Activity of the Enzyme Acetate Kinase
Published on: December 19, 2011
Cholinesterase: substrate inhibition and substrate activation
1Institute for Medical Research and Occupational Health, Zagreb, Croatia.
Abstract:
The relationship between activities and substrate concentrations (pS-curves) was analysed for reactions of acetylcholinesterase (EC 3.1.1.7) and butyrylcholinesterase (EC 3.1.1.8). Catalytic constants Km, Kss, Vm, n and b were calculated from the Michaelis, Haldane, Hill and Webb equations in order to assess whether a given substrate also acts as an inhibitor or activator. It is suggested that the term substrate inhibition should only be attributed to substrates revealing bell-shaped pS-curves, while the terms apparent substrate inhibition or apparent substrate activation should relate to calculated values of the catalytic constants.
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