Repurposing GS-441524 to inhibit biofilm formation and virulence of Bacillus cereus.

Bacillus cereus is a resilient foodborne pathogen, with biofilm formation and virulence regulated by quorum sensing (QS). This study evaluates GS-441524, the active metabolite of remdesivir, as an anti-virulence agent against B. cereus. At sub-inhibitory concentrations, GS-441524 dose-dependently reduced protease, lipase, hemolysin, and AI-2 production, impaired motility, and inhibited biofilm formation. Gene expression analysis showed downregulation of key QS (papR, luxS, plcR) and toxin (hblD, cytK, nprB) genes. Molecular docking indicated strong binding to HblD. In a Galleria mellonella model, GS-441524 enhanced survival upon B. cereus challenge. These findings demonstrate that GS-441524 disrupts QS and virulence, offering a promising strategy to control B. cereus.