Applied and Environmental Microbiology (2020) 86 (12 - e00476-20)

From Pestinfo-Wiki
Jump to: navigation, search
Bt-toxin-crystals.jpgSelected publication
you are invited to contribute to
the discussion section (above tab)
Javier Caballero, Nerea Jiménez-Moreno, Irene Orera, Trevor Williams, Ana B. Fernández, Maite Villanueva, Juan Ferré, Primitivo Caballero and Carmen Ancín-Azpilicueta (2020)
Unraveling the composition of insecticidal crystal proteins in Bacillus thuringiensis: a proteomics approach
Applied and Environmental Microbiology 86 (12 - e00476-20)
Abstract: Bacillus thuringiensis (Bt) is the most widely used active ingredient for biological insecticides. The composition of δ-endotoxins (Cry and Cyt proteins) in the parasporal crystal determines the toxicity profile of each Bt strain. However, a reliable method for their identification and quantification has not been available, due to the high sequence identity of the genes that encode the δ-endotoxins and the toxins themselves. Here, we have developed an accurate and reproducible mass spectrometry-based method (liquid chromatography-tandem mass spectrometry-multiple reaction monitoring [LC-MS/MS-MRM]) using isotopically labeled proteotypic peptides for each protein in a particular mixture to determine the relative proportion of each δ-endotoxin within the crystal. To validate the method, artificial mixtures containing Cry1Aa, Cry2Aa, and Cry6Aa were analyzed. Determination of the relative abundance of proteins (in molarity) with our method was in good agreement with the expected values. This method was then applied to the most common commercial Bt-based products, DiPel DF, XenTari GD, VectoBac 12S, and Novodor, in which between three and six δ-endotoxins were identified and quantified in each product. This novel approach is of great value for the characterization of Bt-based products, not only providing information on host range, but also for monitoring industrial crystal production and quality control and product registration for Bt-based insecticides.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Database assignments for author(s): Trevor Williams, Juan Ferre, Primitivo Caballero

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

Pest and/or beneficial records:

Beneficial Pest/Disease/Weed Crop/Product Country Quarant.
Bacillus thuringiensis Cry1A-toxin (entomopathogen)
Bacillus thuringiensis Cry2A-toxin (entomopathogen)
Bacillus thuringiensis Cry6A-toxin (against nematodes)