Hydrolysis of organophosphorus pesticides in soil: New opportunities with ecocompatible immobilized His6-OPH

Immobilized biocatalyst developed on the basis of hexahistidine-tagged organophosphorus hydrolase (His(6)-OPH) was tried for bioremediation of various soil samples heavily contaminated by pesticides. Various cellulose-containing carriers being agricultural wastes were applied for His(6)-OPH immobilization enabling stabilization of the enzyme and its retention in the organophosphonis pesticides destruction zone. Straw-based immobilized enzymatic preparation ensured the decomposition of 630 mg Paraoxon or 850 mg Diazinon or 185 mg Parathion per kg soil in less than 10 days; meanwhile, the half-life of active biocatalyst in sand was estimated as 130 days. Immobilized His(6)-OPH allowed to hydrolyze pesticide in the case of its reintroduction into soil samples. The influence of soil type on the kinetics of organophosphorus pesticides destruction was revealed. (C) 2011 Elsevier Ltd. All rights reserved.