Rapidly hydrolyzes choline released into the synapse. acetylcholine + H2O = acetate + choline + H(+) A number of strains are susceptible to insecticides while others are resistant. Insensitivity to insecticides results from a loss of sensitivity of acetylcholinesterase to organophosphates and carbamates and is due to a variant at position 97. Belongs to the type-B carboxylesterase/lipase family.