Substrate Specificity of Cholinesterases in Various Representatives of the Animal Kingdom

Abstract

This review summarizes the literature data as well as experimental results obtained at our Institute over a period of 50 years on the substrate specificity of cholinesterases–acetylcholine acetylhydrolases (EC 3.1.1.7) and acylcholine acylhydrolases (EC 3.1.1.8). The parameters of enzymatic hydrolysis of oxo- and thiocholine and β-methylcholine esters in different organs and tissues were analyzed in 66 animal species including 22 chordate, 20 insect, 1 mite, 17 mollusk, 4 nematode, and 2 flatworm species. Our substrate specificity studies and extensive data on the inhibitory specificity obtained using irreversible organophosphorous inhibitors and reversible effectors unequivocally indicate that the cholinesterase family is characterized by a clear-cut species and tissue specificity.