Cloning of an organophosphorus hydrolase (opdD) gene of Lactobacillus sakei WCP904 isolated from chlorpyrifos-impregnated kimchi and hydrolysis activities of its gene product for organophosphorus pesticides

Md Azizul Haque,Soo Young Hong,Su Cheol Kim,Kye Man Cho,Chung Eun Hwang

doi:10.1007/s13765-018-0397-x

Abstract

Chlorpyrifos (CP) residues are absorbed from soil and often found in Korean cabbages that are being used to make kimchi. Lactobacillus sakei WCP904, harboring the organophosphorus (OP) hydrolase gene opdD, was isolated from CP-impregnated mulkimchi. The cloned gene opdD from strain CP904 comprises 825 base-pair nucleotides that encode 274 amino acids. The recombinant Escherichia coli harboring the opdD gene depleted 73% of CP after 6 days in M9 medium. In fact, the OpdD protein is a novel member of the GHSQG family of esterolytic enzymes or lactic acid bacterial Opd groups. The molecular weight of the OpdD protein was estimated to be 31 kDa using SDS-PAGE. Broad-spectrum activities of the OpdD protein were obtained against OP insecticides containing both P–O and P–S bonds. The OpdD protein exhibits maximum activity at 30 °C with pH 6. No enzyme activities of the mutated OpdD (Ser116 → Ala116) protein toward ρ-nitrophenyl butyrate and CP substrates were observed. These results suggested that the strain WCP904 scavenges insecticide residues from mulkimchi vegetables, thus abolishing health hazards by secreting OP hydrolase during fermentation.

Highlights

Chlorpyrifos (CP) is an organophosphorus (OP) insecticide being extensively applied on agricultural crops and vegetables worldwide [1]
The isolated L. sakei WCP904 was screened for its ability to degrade OP insecticides
When the yeolmu-mulkimchi was fermented contaminated with CP, Cho et al [7] observed a higher population of L. sakei WCP904

Summary

Introduction

Chlorpyrifos (CP) is an organophosphorus (OP) insecticide being extensively applied on agricultural crops and vegetables worldwide [1]. CP residues are gradually impregnated into the environment and persist for an unpredictable period [2], which poses a great threat to human health [3]. The fate of CP in the environment has been widely studied, and its half-life in soil varies from 10 to 120 days [3, 4], resulting in 3,5,6-trichloro-2-pyridinol (TCP) as the major degradation product. Hwang and Moon [5] recently published data, reporting that the residual CP ratios in Korean cabbage were 0.93–6.01 and 0.57–2.61%, respectively. Was used in the detoxification of these insecticides on vegetables [6]. Cho et al [7] reported that lactic acid bacteria (LAB) such as Leuconostoc mesenteroides WCP907, Lactobacillus brevis WCP902, Lactobacillus plantarum WCP931, and Lactobacillus sakei WCP904 utilize OP insecticides as the sole sources of carbon and phosphorus and scavenged the insecticides from yeolmumulkimchi vegetables during fermentation

Methods

Results

Conclusion