Detection and identification of vegetative insecticidal proteins vip3 genes of Bacillus thuringiensis strains using polymerase chain reaction-high resolution melt analysis.

In this study, vegetative insecticidal proteins vip3 genes from Bacillus thuringiensis strains were detected based on polymerase chain reaction-high resolution melt (PCR-HRM) analysis. A pair of primers was designed according to the conservative sequences in 150 bp region of the known vip3 subfamily. The 150 bp regions of difference vip3 genes have only a few nucleotide difference vip3 genes were detected in 8 of 11 standard B. thuringiensis strains, and vip3Aa genes, vip3Af genes and vip3Ba gene can be distinguished as different melting curves by this method. The results demonstrate the utility of the HRM assay for mutant screening using vip3 gene. The PCR-HRM method may be a valuable and reliable tool for specific detection and identification of vip3 genes.