Aim: Aim: Develop shelf-stable, region-specific recombinant antivenoms for Pakistani snake species using AI-driven protein design.
Potential impact: Address the 40,000-50,000 annual snakebite cases and 8,200 deaths in Pakistan. Replace expensive imported antivenoms with locally-manufacturable alternatives, reducing costs while eliminating refrigeration dependency critical for rural areas.
Previous work: As a proof of concept, we employed existing approaches to design de novo binders against Russell's viper PLA₂ toxin, achieving reasonable structural confidence (pLDDT 94, pTM 0.87) with sub-micromolar binding affinity (Kd ~1.6 µM).
Method: Create consensus venom peptides from Pakistan's four most common venomous snakes, then deploy RFdiffusion for backbone generation, ProteinMPNN for sequence optimization, and AlphaFold2/Rosetta validation to generate 40 top binder candidates per target. Express and purify selected candidates using Gibson assembly and E. coli expression systems.
Current progress: Currently deploying advanced diffusion-based protein design tools and optimizing computational pipeline for large-scale, multi-target binder generation.
Next Steps: Generate consensus peptides, screen top 3 highest-affinity binders, and validate through recombinant expression and in vitro neutralization assays over 18 months.
a. Structure of venom protein 3FTxs59 (Protein Data Bank (PDB) 1QKD) b. Representation of type IA cytotoxin60 (dark pink) (PDB 5NQ4) interacting with a lipid bilayer. d. Schematic showing α-cobratoxin binder design using RFdiffusion. Starting from a random distribution of residues around the specified β-strands in the target toxin (dark purple), successive RFdiffusion denoising steps progressively removed the noise leading at the end of the trajectory to a folded structure interacting with α-cobratoxin β-strands. Image credit: Torres et al. (2024)
(Left) Overlay of PLA₂ (grey) and the de novo binder (blue) from the top AlphaFold-Multimer model. High pTM (0.866) and ipTM (0.805) suggest a reliable, well-defined interface. (Right) Contact-dot view showing extensive inter-chain contacts (≤ 4 Å, red dots), with ~1,117 Ų buried surface area. Predicted binding energy: ΔG_bind = –7.9 kcal/mol; K_d ≈ 1.6 µM (PRODIGY).