The invention provides a phosphotriesterase
mutant as well as a preparation method and application of the phosphotriesterase
mutant. According to the invention, a
mutant with phosphotriesterase activity markedly improved is finally obtained by starting from a phosphotriesterase
gene which is from
Geobacillus kaustophilus HTA426 of thermophilic
bacteria and then carrying out rounds of
mutation and screening through an error-prone PCR (
Polymerase Chain Reaction) method; and the mutations involved in
amino acid sequence of the mutant are Phe28Ile, Tyr99Leu, Thr171Ser, Phe228Leu, Asn269Ser, Val270Gly, Trp271Cys and Gly273Asp. Compared with common organic phosphorous insecticides, the
wild type specific activity of the mutant is markedly improved and the mutant has wide application prospect in the field of
biodegradation of organic phosphorous poisions.