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Updated: Apr 29, 2026

Functional Characterization of Carboxylesterases in Insecticide Resistant House Flies, Musca Domestica
Published on: August 23, 2018
Chemoenzymatic resolution of rac-malathion
David M Hitt1, Yamina Belabassi2, Joyce Suhy2
1ATERIS Technologies, 901 N Orange Street, Missoula MT 59802, USA ; Department of Natural Sciences, Carroll College, 1601 N. Benton Ave., Helena, MT 59625, USA.
Abstract:
Malathion, diethyl 2-[(dimethoxyphosphorothioyl)sulfanyl]butanedioate, is an organophosphate used to control insect pests. Malathion contains a diethyl succinate moiety that is a known functional group susceptible to desymmetrizing enzymes such as esterases that selectively react with a single enantiomer. Purified rac-malathion was subjected to hydrolysis at the diethyl succinate moiety of malathion under various conditions using wild type pig liver esterase to form (S)-malathion (12 % ee) and ~ 3:2 mixture of α- and β-monoacids of (R)-malathion. Technical malathion could not be enriched due to the presence of esterase inhibitors. Further investigation of this resolution using a panel of six PLE isoenzymes also demonstrated formation of (S)-malathion, however, an improvement of up to 56 % ee was obtained.
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