A Bacillus thuringiensis ΔcdsR-based expression system for insecticidal proteins identified using AlphaFold3

Area of Science:

• Agricultural Science
• Microbiology
• Biotechnology

Background:

• Bacillus thuringiensis (Bt) biopesticides are crucial for Integrated Pest Management (IPM).
• Discovering new pesticidal proteins is advancing through genomics and bioinformatics.
• Existing Bt formulations face challenges in efficacy and stability.

Purpose of the Study:

• To identify novel pesticidal protein genes using structure prediction.
• To engineer a versatile Bt chassis strain for expressing these new proteins.
• To improve biopesticide efficacy, stability, and environmental safety.

Main Methods:

• Utilized AlphaFold3 for structure-based identification of candidate pesticidal genes.
• Developed a novel Bt chassis strain with a deleted cdsR gene and a controllable cell death pathway.
• Engineered the chassis for cytoplasmic hyperexpression of recombinant proteins, decoupling toxin production from sporulation.

Main Results:

• Identified several novel pesticidal protein candidates.
• The engineered Bt chassis strain demonstrated successful hyperexpression and encapsulation of recombinant proteins.
• Expressed proteins showed insecticidal activity, superior UV stability, and enhanced environmental safety compared to conventional Bt.

Conclusions:

• The developed Bt chassis strain offers a versatile platform for next-generation biopesticide discovery and production.
• This approach advances sustainable pest management through innovative biocontrol solutions.
• The findings support the development of more effective and environmentally friendly pest control strategies.