Organophosphorus and carbamate insecticides are toxic to insects and mammals by virtue of their ability to inactivate the enzyme acetylcholinesterase. This review addresses the mechanism of inhibition of acetylcholinesterase by organophosphorus and carbamate esters, focusing on structural requirements necessary for anticholinesterase activity. The inhibition of acetylcholinesterase by these com...

Organophosphorus (OP) insecticides are used worldwide to protect agricultural crops and dwellings. These chemicals phosphorylate diverse serine hydrolases, including acetylcholinesterase. Among them, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), components of the endocannabinoid signaling system (ECS) in male reproductive organs, are candidate targets of OP insecticide-i...

We have developed a novel optical biosensor device using recombinant methyl parathion hydrolase (MPH) enzyme immobilized on agarose by metal-chelate affinity to detect organophosphorus (OP) compounds with a nitrophenyl group. The biosensor principle is based on the optical measurement of the product of OP catalysis by MPH (p-nitrophenol). Briefly, MPH containing six sequential histidines (6 × H...

Variants of human paraoxonase 1 (PON1) are being developed as catalytic bioscavengers for the organophosphorus chemical warfare agents (OP). It is preferable that the new PON1 variants have broad spectrum hydrolase activities to hydrolyze both G- and V-class OPs. H115W PON1 has shown improvements over wild type PON1 in its capacity to hydrolyze some OP compounds. We improved upon these activiti...

Paraoxonase 1 (PON1) is a member of a tandem 3-gene family localized on human chromosome 7q21-22.1 High-density lipoprotein-associated PON12,3 and PON34,5 are synthesized primarily in the liver, whereas PON2 is ubiquitously expressed.1 PON1 was initially characterized and named for its ability to hydrolyze paraoxon, the toxic oxon metabolite of parathion.6 Although Aldridge6 proposed in 1953 th...