In silico pharmacological analysis of Tinospora cordifolia compounds targeting African swine fever virus B175L

Abstract

African swine fever virus (ASFV) is a highly lethal DNA virus that suppresses the hosts immune response by establishing infection. B175L, one of its key immune evasion proteins, directly inhibits STING-mediated type I interferon (IFN-I) signaling, preventing antiviral defense activation. Thus, targeting B175L could be a promising strategy for antiviral drug development as effective ASFV inhibitors remain unidentified. In this study, we investigated the potential of the Tinospora cordifolia plants bioactive compounds to disrupt B175Ls function, restoring immune signaling. Gas chromatography-mass spectrometry (GC-MS) analysis of T. cordifolia stems methanol extract identified 124 compounds, of which 52 met SwissADME and DataWarrior criteria for drug-likeness and safety. We generated a highly accurate 3D B175L model with strong confidence scores for the structure accuracy, utilizing AlphaFold3. Virtual screening was performed using PyRx 0.8, and the top 4 ligands with binding affinities exceeding -6 kcal/mol advanced to CB-Dock2 and UCSF Chimera. Among them, Benzaldehyde, 5-bromo-2-hydroxy-, (5-trifluoromethyl-2pyridyl)hydrazone exhibited the highest binding affinity (-8.2 kcal/mol), confirming its strong interactions at the active site of B175L. Molecular dynamics (MD) simulations demonstrated the compounds stability, with root mean square deviation and fluctuation (RMSD, RMSF) indicating minimal conformational changes (<2 [A]). The compound maintained stable hydrogen bonds and hydrophobic interactions, reinforcing structural robustness. Taken together, these results clearly emphasize T. cordifolia-derived Benzaldehyde, 5-bromo-2-hydroxy-, (5-trifluoromethyl-2-pyridyl)hydrazone as a promising B175L inhibitor, advancing exploration towards effective antiviral solutions for ASFV.