Study on the Degradation Effect of Three Organophosphorus Hydrolase Mutant on Sarin

¹ 66072 PLA troops, 100043, Beijing, China
² Institute of NBC Defense, 102205, Beijing, China
³ State Key Laboratory of NBC prevention for Civilian, 102205, Beijing, China ;

^a Corresponding author: gqm@nbcde.cn
^b fhxihl@163.com
^c lm@nbcde.con

Abstract

Organophosphorus hydrolase can effectively degrade organic phosphorus compounds such as sarin. In this study, we constructed a recombinant Bacillus subtilis mutant expressing organophosphorus hydrolase, measured the effect of the mutant on the degradation rate of nerve agent sarin, and selected the optimal mutation scheme. Three different hydrolase mutant genes, 257L, 257Y and 303T, were ligated to PMA0911 vector and transferred into Bacillus subtilis WB800 to construct the target recombinant strain successfully. The recombinant bacteria secreted the target protein by fermentation. The effect of enzyme protein on the degradation of sarin was determined by the benzidine method. The optimal mutant was screened, and its enzymatic performance was explored. The effects of three organophosphorus hydrolase mutants on the hydrolysis rate of sarin were detected. The results showed that the 257Y mutant accelerated the hydrolysis of sarin significantly. Point mutation can improve the enzyme activity of wild-type organophosphorus hydrolase to a certain extent, laying the foundation for subsequent in-depth research.