Discovery of a potent inhibitor, D-132, targeting AsfvPolX, via protein-DNA complex‐guided pharmacophore screening and in vitro molecular characterizations

• Published in: Virus research 2024-06, Vol.344, p.199359-199359, Article 199359
• Main Authors: Wu, Yi-Chen, Lai, Hui-Xiang, Li, Ji-Min, Fung, Kit-Man, Tseng, Tien-Sheng
• Format: Article
• Language: English
• Subjects: Antiviral inhibitor; ASFV; AsfvPolX; Drug discovery; Fluorescence polarization; LSPR; Molecular docking; Pharmacophore-based inhibitor screening
• ISSN: 0168-1702; 1872-7492
• DOI: 10.1016/j.virusres.2024.199359

•Inhibiting AsfvPolX disrupts ASFV replication, offering a strategy to control infections.•D-132 strongly binds (KD = 6.9 µM) and disrupts (IC50 = 2.8 µM) AsfvPolX-DNA complex.•D-132 interacts with key residues (R42, N48, Q98, E100, F102, and F116) of AsfvPolX.•D-132 holds promise as a lead compound against ASFV infections. The heightened transmissibility and capacity of African swine fever virus (ASFV) induce fatal diseases in domestic pigs and wild boars, posing significant economic repercussions and global threats. Despite extensive research efforts, the development of potent vaccines or treatments for ASFV remains a persistent challenge. Recently, inhibiting the AsfvPolX, a key DNA repair enzyme, emerges as a feasible strategy to disrupt viral replication and control ASFV infections. In this study, a comprehensive approach involving pharmacophore-based inhibitor screening, coupled with biochemical and biophysical analyses, were implemented to identify, characterize, and validate potential inhibitors targeting AsfvPolX. The constructed pharmacophore model, Phar-PolX-S, demonstrated efficacy in identifying a potent inhibitor, D-132 (IC50 = 2.8 ± 0.2 µM), disrupting the formation of the AsfvPolX-DNA complex. Notably, D-132 exhibited strong binding to AsfvPolX (KD = 6.9 ± 2.2 µM) through a slow-on-fast-off binding mechanism. Employing molecular modeling, it was elucidated that D-132 predominantly binds in-between the palm and finger domains of AsfvPolX, with crucial residues (R42, N48, Q98, E100, F102, and F116) identified as hotspots for structure-based inhibitor optimization. Distinctively characterized by a 1,2,5,6-tetrathiocane with modifications at the 3 and 8 positions involving ethanesulfonates, D-132 holds considerable promise as a lead compound for the development of innovative agents to combat ASFV infections.