Review on Microbial Carboxylesterase: General Properties and Role in Organophosphate Pesticides Degradation

Abstract

Abstract - Carboxylesterases (CEs) are a family of enzymes that are important in the hydrolysis of a large number of endogenous and xenobiotic ester-containing compounds, such as organophosphorus (OP) pesticides. Recently, research activities in this area have shown that a diverse range of enzymes isolated from microbes are available for the biodegradation of OP. This review examines uses of microbial CE activity in environmental monitoring with a specific emphasis on pesticides. This article serves to introduce CEs, their classification, biochemical characterization, structure and their role in detoxification reactions. In addition, recent advances in enhancing enzyme activity for efficient biodegradation of OP are presented. Keywords - Carboxylesterase, Classification, Biochemical Characterization, Organophosphate Pesticides 1. Introduction Introduction of synthetic pesticides especially organophosphates and its application for eradication of pest has led its exposure to target and non-target organism. These pesticides possess ester bonds which are inactivated by hydrolysis involving CE. Due to its wide spread application and subsequent exposure, the pressure to remove the OP pesticides has led to the evolution of hydrolysis enzymatic system especially the CEs. Such enzymes form the basis of several bioremediation strategies intended to reduce the environmental impacts of pesticide residues. This review describes CEs which are among the major enzymes employed in the bioremediation of pesticide residues and some of the strategies by which they are employed. Many man-made pesticides are ester compounds. Hydrolysis, photolysis, and oxidation reactions with minerals and microbial degradation are some of the important environmental processes that may convert pesticides into non toxic or less toxic compound. Applying enzymes to transform or degrade pesticides is an innovative treatment technique for removal of these chemicals from polluted environments. Furthermore, enzymatic degradation of pesticides provides the possibility of both environmentally friendly and