Use of a pooled clone method to isolate a novel Bacillus thuringiensis Cry2A toxin with activity against Ostrinia furnacalis

J Invertebr Pathol. 2013 Sep;114(1):31-3. doi: 10.1016/j.jip.2013.05.005. Epub 2013 May 24.

Abstract

A pooled clone method was developed to screen for cry2A genes. This metagenomic method avoids the need to analyse isolated Bacillus thuringiensis strains by performing gene specific PCR on plasmid-enriched DNA prepared from a pooled soil sample. Using this approach the novel holotype gene cry2Ah1 was cloned and characterized. The toxin gene was over-expressed in Escherichia coli Rosetta (DE3) and the expressed toxin accumulated in both the soluble and insoluble fractions. The soluble Cry2Ah1 was found to have a weight loss activity against Ostrinia furnacalis, and a growth inhibitory activity to both Cry1Ac-susceptible and resistant Helicoverpa armigera populations.

Keywords: Bacillus thuringiensis; Cry1Ac-resistance; Cry2Ah1; Helicoverpa armigera.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacillus thuringiensis Toxins
  • Bacterial Proteins / isolation & purification*
  • Cloning, Molecular / methods
  • Endotoxins / isolation & purification*
  • Escherichia coli / genetics
  • Hemolysin Proteins / isolation & purification*
  • Insecticides / isolation & purification*
  • Moths*
  • Pest Control, Biological

Substances

  • Bacillus thuringiensis Toxins
  • Bacterial Proteins
  • Endotoxins
  • Hemolysin Proteins
  • Insecticides
  • insecticidal crystal protein, Bacillus Thuringiensis