In-silico Studies Calculated a New Chitin Oligomer Binding Site Inside Vicilin: A Potent Antifungal and Insecticidal Agent

Abstract

Vicilins are major seed storage proteins and show differential binding affinities toward sugar moieties of fungal cell wall and insect gut epithelium. Hence, purpose of study is the thorough in-silico characterization of interactions between vicilin and chitin oligomer followed by fungal and insecticidal bioassays. This work covers the molecular simulation studies explaining the interactions between Pisum sativum vicilin ( PsV) and chitin oligomer followed by protein bioassay against different pathogens. LC-MS/MS of purified PsV (∼50 kDa) generated residual data along high pea vicilin homology (UniProtKB ID; P13918). Predicted model ( PsV) indicated the characteristic homotrimer joined through head-to-tail association and each monomer is containing a bicupin domain. PsV site map analysis showed a new site (Site 4) into which molecular docking confirmed the strong binding of chitin oligomer (GlcNAc)4. Molecular dynamics simulation data (50 ns) indicated that chitin-binding site was comprised of 8 residues (DKEDRNEN). However, aspartate and glutamate significantly contributed in the stability of ligand binding. Computational findings were further verified via significant growth inhibition of Aspergillus flavus, A. niger, and Fusarium oxysporum against PsV. Additionally, the substantial adult population of Brevicoryne brassicae was reduced and different life stages of Tribolium castaneum also showed significant mortality.

Seed storage proteins and seed coat compounds additively influence Callosobruchus maculatus Fab. tolerance in selected cowpea (Vigna unguiculata L. Walp.) varieties

“…Not surprisingly, this fraction is associated with the vicilin family as mentioned by several authors (Saeed et al, 2022;Salgado et al, 2002). Other studies have also implicated vicilin as a protein that protects the cowpea seed against the damaging effect of the cowpea C. maculatus (Kpoviessi et al, 2021;Miranda et al, 2020;Rangel et al, 2003;Saeed et al, 2022). We infer that the presence of this protein plays a crucial role in C. maculatus tolerance in cowpea.…”

“…In the current study, only a 51 kDa fraction was observed to be associated with two C. maculatus tolerance measures, PAE and H.S.I., whereas other fractions were associated with one measure or the other singly. Not surprisingly, this fraction is associated with the vicilin family as mentioned by several authors (Saeed et al, 2022;Salgado et al, 2002). Other studies have also implicated vicilin as a protein that protects the cowpea seed against the damaging effect of the cowpea C. maculatus (Kpoviessi et al, 2021;Miranda et al, 2020;Rangel et al, 2003;Saeed et al, 2022).…”