COMPUTATIONAL DOCKING AND STRUCTURAL ANALYSIS OF THE SSPC STORAGE PROTEIN FROM PIGEON PEA (CAJANUS CAJAN) FOR ALLERGENICITY AND DOMAIN MODULATION

ABSTRACT Pigeonpea (Cajanus cajan) is a nutritionally important legume, yet seed storage proteins (SSPs) such as SSPC may contribute to allergenicity. This study employed an integrative in silico approach to investigate the structural characteristics, allergenic potential, and ligand interactions of SSPC. The amino acid sequence of SSPC was analyzed using PSIPRED, SOPMA, AlphaFold2, SWISS-MODEL, and I-TASSER, with 3D structures validated via PROCHECK, ERRAT, Verify3D, and ProSA-web, and potential binding pockets identified using CASTp, PrankWeb, and COACH. GC-MS analysis of C. cajan extracts identified fifteen phytochemical compounds, six of which including quercetin, kaempferol, and ferulic acid showed favorable docking interactions with SSPC, stabilizing key residues such as Asn3. Molecular docking and pharmacokinetic analyses indicated positive human intestinal absorption, non-inhibition of CYP2D6, and, in most cases, blood–brain barrier permeability, suggesting bioavailability and safety. The study concludes that SSPC possesses well-defined ligand-binding sites and that selected phytochemicals can potentially modulate allergenic epitopes. In silico approaches provide a rapid, cost-effective, and ethical method to predict allergenic potential and guide protein modulation. Based on these findings, further experimental validation through in vitro and in vivo assays, structural modulation studies, bioactive compound development, expanded computational screening, and integration into pigeonpea breeding programs is recommended to enhance nutritional quality while reducing allergenicity. This work highlights the value of combining computational modeling and phytochemical analysis to inform future research and food safety strategies.