Expression of a Novel Hydrolase from Klebsiella oxytoca for Carbendazim Residue Degradation on the Surface of Fruit and Vegetable

In order to explore enzymatic method for pesticide residue degradation on surface of fruits,a novel carbendazim degradation bacteria was isolated and the carbendazim hydrolase coding gene was amplified. The results showed that a novel Klebsiella oxytoca KO-1 which was able to survive with carbendazim as the sole carbon source was screened and identified. Moreover,a 837 bp hydrolase coding gene was amplified by PCR using degenerate primers,and hydrolase KY-1 that catalyzing carbendazim degradation was expressed and purified in E. coli BL 21.KY-1 successfully catalyzed carbendazim into 2-aminobenzimidazole depends on HPLC-MS analysis results,and the relative enzymatic activity was 36.8 U/mg. The enzyme preparation of KY-1 successfully accelerated carbendazim degradation rate on the surface of cucumber,potato,tomato and strawberry,and the highest acceleration rate was 37.3%. In conclusion,a carbendazim degradation bacterium was isolated and the enzyme preparation was prepared. Moreover,this work lay the foundation for the enzymatic restoration of pesticide contaminated fruits.