Bacillus thuringiensis bel protein enhances the toxicity of Cry1Ac protein to Helicoverpa armigera larvae by degrading insect intestinal mucin.

ABSTRACT: Bacillus thuringiensis has been used as a bioinsecticide to control agricultural insects. Bacillus cereus group genomes were found to have a Bacillus enhancin-like (bel) gene, encoding a peptide with 20 to 30% identity to viral enhancin protein, which can enhance viral infection by degradation of the peritrophic matrix (PM) of the insect midgut. In this study, the bel gene was found to have an activity similar to that of the viral enhancin gene. A bel knockout mutant was constructed by using a plasmid-free B. thuringiensis derivative, BMB171. The 50% lethal concentrations of this mutant plus the cry1Ac insecticidal protein gene were about 5.8-fold higher than those of the BMB171 strain. When purified Bel was mixed with the Cry1Ac protein and fed to Helicoverpa armigera larvae, 3 mug/ml Cry

SUBMITTER: Fang S 

PROVIDER: S-EPMC2725464 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature