Targeting Crimean-Congo hemorrhagic fever virus: computational and MD-driven discovery of Moringa oleifera peptides against the RdRp-embedded OTU protease.

Crimean-Congo Hemorrhagic Fever Virus (CCHFV) is a tick-borne pathogen causes hemorrhagic disease with high fatality rates, and no approved vaccines/antivirals currently exist. The viral L protein contains a unique ovarian tumor (OTU) protease domain that cleaves ubiquitin and ubiquitin-like modifiers from host proteins, thereby aiding immune evasion and viral replication. Targeting the OTU domain represents a promising strategy for therapeutic intervention. Peptides obtained from Moringa oleifera proteome that mimic the binding mode of the endogenous ubiquitin molecule. These peptides were computationally screened for their ability to bind the OTU protease domain, incorporating both conventional cysteine protease inhibitors and protein-protein interaction interface mimetics. This study revealed Pep31 with a strong balance of binding affinity, solubility, and structural stability, highlighting its potential as a novel OTU protease inhibitor. While our findings are computational, they provide a foundation for experimental validation and the future development of peptide-based antivirals targeting CCHFV.