Antimicrobial peptide-based biopesticide formulation from natural sources

Overview

This research proposes the development of a biopesticide formulation based on Snakin antimicrobial peptides (AMPs) identified in garlic, mango, and eucalyptus. Cationic host defense peptides are naturally produced by bacteria, fungi, plants, and animals, and exhibit a broad spectrum of antimicrobial activity against viruses, bacteria, fungi, and parasites. The project focuses on recombinant production of these peptides to enable scalable, sustainable crop protection solutions that reduce reliance on conventional chemical pesticides.

Technical specifications

Core technology:

• Recombinant expression of Snakin peptides (SN-1 and homologs) from garlic, mango, and eucalyptus
• Peptide sequences share 47%, 83%, and 77% identity with garlic SN-1, respectively, with conserved secondary structures and disulfide bridges
• 12 characteristic cysteines preserved across all target peptides, maintaining structural integrity

Expression system:

• Bacterial recombinant expression using YkgR or MBP fusion tags, plus His6X affinity tags
• Strategy designed to improve transport to the periplasmic space, reduce inclusion body formation, and minimize cytotoxicity toward the expression host while enhancing solubility

Formulation enhancements:

• Incorporation of non-canonical (unconventional) amino acids to improve peptide stability
• Nanoencapsulation using biodegradable materials to ensure prolonged release and field persistence
• Cytotoxicity evaluation to confirm safety profile

Target pathogens for validation:

• Fungi: Aspergillus flavus, Aspergillus niger
• Bacteria: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Klebsiella sp., Salmonella typhimurium, Citrobacter sp.

Technology readiness level

The project is at an early-to-mid stage of development. Sequence identification and in-silico modeling have been completed, confirming structural conservation of the Snakin peptides across target species. Recombinant expression constructs have been designed and cloning is underway. Future validation will include in vitro antimicrobial and fungicidal testing against key crop pathogens, followed by expression with non-canonical amino acids, cytotoxicity assessment, and nanoencapsulation studies. The technology is currently at laboratory validation stage, with formulation optimization and field readiness remaining as next steps.