Abstract
A novel pyrethroid-degrading esterase gene pytY was isolated from the genomic library of Ochrobactrum anthropi YZ-1. It possesses an open reading frame (ORF) of 897 bp. Blast search showed that its deduced amino acid sequence shares moderate identities (30% to 46%) with most homologous esterases. Phylogenetic analysis revealed that PytY is a member of the esterase VI family. pytY showed very low sequence similarity compared with reported pyrethroid-degrading genes. PytY was expressed, purified, and characterized. Enzyme assay revealed that PytY is a broad-spectrum degrading enzyme that can degrade various pyrethroids. It is a new pyrethroid-degrading gene and enriches genetic resource. Kinetic constants of Km and Vmax were 2.34 mmol·L−1 and 56.33 nmol min−1, respectively, with lambda-cyhalothrin as substrate. PytY displayed good degrading ability and stability over a broad range of temperature and pH. The optimal temperature and pH were of 35°C and 7.5. No cofactors were required for enzyme activity. The results highlighted the potential use of PytY in the elimination of pyrethroid residuals from contaminated environments.
Highlights
One positive clone was obtained from the remaining genomic library of strain Ochrobactrum anthropi YZ-1
PytY is the second degrading gene isolated from the strain of O. anthropi YZ-1
In the center of the motif, the Ser162 residue acts as nucleophile that catalyzes the hydrolysis of ester bond [36], which is a typical feature of esterase
Summary
They play an important role in control of agriculture, forestry, and indoor pests. Pyrethroids are a large class of synthetic compounds based on the structure of pyrethrin, which is a natural insecticidal toxin from Chrysanthemum cinerariaefolium flowers [1]. Since the discovery and commercial production, pyrethroids have been used for more than 30 years and have accounted for almost 25% of the global pesticide market [2]. They are low toxicity to mammals and have been considered as ideal replacements for some highly toxic pesticides. Traditional organochlorine and organophosphorus pesticides have been phased out due to high toxicity and recalcitrant characteristics. Thereby, the demand for pyrethroid pesticides continues to increase [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
