Recent perspectives on biotechnological production, modulation and applications of glycerophosphoryl diester phosphodiesterases

Abstract

Organophosphate (OP) compounds have been extensively employed as pesticides, insecticides and nerve agents. Stockpiles of chemical warfare agents must be destroyed as recommended by Chemical Weapon Convention (CWC). Toxicity of OP compounds to insects and mammals is due to their ability to inhibit the activity of acetylcholinesterase. Accumulation of acetylcholine leads to overstimulation of nerves, leading to convulsion, paralysis or even death. There is a dire need to decontaminate OP contaminated sites by using inexpensive and eco-friendly agents. Recently, OP hydrolyzing enzymes such as glycerophosphoryl diester phosphodiesterases (GDPDs) emerged as appealing agents to clean-up OP contaminated environmental sites. GDPDs are well known for enzymatic generation of glycerol 3-phosphate and corresponding alcoholic moiety from glycerophosphodiesters. Additionally, they are also involved in hydrolysis of OP compounds and degradative products of nerve agents. In the current review, structural and functional characteristics of GDPDs have been elaborated. Production of GDPDs from natural sources is quiet low so the current study aims at recombinant production of GDPDs from various sources. Comparative analysis of biochemical characteristics of various GDPDs indicated that thermostable GDPDs are active over broad temperature and pH range. In addition, thermostable GDPDs are resistant to high concentrations of organic solvents as well as metal ions. In order to enhance their practical utility, different engineering approaches (directed evolution, rational design and site-saturation mutagenesis) as well as immobilization strategies can be utilized to improve catalytic properties of GDPDs. Thus, the current review highlights the utilization of recombinant engineered free or immobilized GDPDs as tools in OP bioremediation.