Carboxy lesterase

Wadkins, R.M., et al. 2004. Discovery of novel selective inhibitors of human intestinal carboxy-lesterase for the amelioration of irinotecan-induced diarrhea Synthesis, quantitative structure-activity relationship analysis, and biological activity. Mol Pharmacol 65 1336. 

Carboxylamidase activity toward p-nitroacetanilide has been detected in different insect species from the orders Lepidoptera, Orthoptera, and Dictyoptera. The carboxylamidase from fall army worm larvae has been purified. The purified enzyme is a monomer with a molecular weight of 59,000-60,000 Da. The enzyme is inhibited by the hydrolase inhibitors paraoxon, triphenyl phosphate, eserine, and phenylmethylsulfonyl fluoride, showing I50 values of 4.7 iM, 0.2 mM, 16 iM, and 90 iM, respectively. Activity is also completely inhibited by the organophosphorus insecticides profenfos and dichlorvos at 0.1 mM. The enzyme is active toward other amides, such as acetanilide and phenacetin, and various a- and p-naphtholic esters. Based on the purification factor, substrate specificity, and sensitivity to hydrolase inhibitors, the carboxylamidase appears to be different from carboxy-lesterases in the fall army worm (Yu and Nguyen, 1998). 

Hydrolases. Hydrolases constitute a very complex ensemble of enzymes many of which are known or suspected to be involved in xenobiotic metabolism. Relevant enzymes among the serine hydrolases include carboxy-lesterases (carboxylic-ester hydrolase EC... 

As reported by Russel et al., carried out metabolic smdies showed that pyrethroids are mainly metabolized by oxidation and ester cleavage, which are mediated by cytochrome isoforms and carboxylesterases, respectively (Russel et al. 2011). The biodegradation of synthetic pyrethroids is involved in the resistance of insects, in addition carboxylesterases, cytochromes P450 (CYPs) and GSTs (glutathione-5 -transferases) have all been implicated in this resistance. Intense bands of carboxy-lesterase activity in nondenaturing polyacrylamide gel had been associated with resistance to synthetic pyrethroids in various species, however, resistance... 

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