Isolation and characterization of a novel native Bacillus thuringiensis strain BRC-HZM2 capable of degrading chlorpyrifos

摘要

Studies were carried out to isolate chlorpyrifos degrading Bacillus thuringiensis (Bt) strains from chlorpyrifos-contaminated samples. Six Bt strains (isolation rate 2.7%) were isolated by modified sodium acetate antibiotic heat treatment, and one novel strain (BRC-HZM2) was selected for further analysis. Phenotype and phylogeny analysis of this strain was conducted on the basis of biochemical reactions, antibiotic sensitivity, 16s rRNA genes, plasmid profile, insecticidal crystal protein profiles, and PCR-RFLP for cry and cyt genes. The degradation rate of chlorpyrifos in liquid culture was estimated during 48h of incubation for the isolate BRC-HZM2. More than 50% of the initial chlorpyrifos concentration degraded within 12h, 88.9% after 48h. These results highlight the potential of the Bt strain for biological control and the bioremediation of environments contaminated with chlorpyrifos.