Quinlan, Joseph E.Soleymani, GhazalShimozono, Tori M.Yang, ZhaominSantos, Webster L.2026-02-182026-02-182025-06-042046-2069PMC12138345d5ra02702k (PII)https://hdl.handle.net/10919/141284Antimicrobial resistance is an imminent health threat worldwide. Development of alternative treatments for drug-resistant microbes is of paramount importance. Targeting virulence factors, such as the type IV pilus construction enzyme PilB, is a strategy of treatment. Recently, we reported the discovery of a potent inhibitor of PilB, the FDA approved drug benserazide (IC<inf>50</inf> = 3.68 μM). Herein, we report the structure-activity relationship profiling of benserazide analogues and identify key moieties that enable PilB inhibition. We found that bis-hydroxyl groups on the ortho position of the aryl ring, a rigid imine, and exchange of the serine for a thiol have resulted in marked improvement in potency. Our studies identified 11c as a PilB inhibitor with an IC<inf>50</inf> of 580 nM and selectivity for PilB over an unrelated ATPase, apyrase. These compounds provide the chemical tools to validate virulence factors as antibacterial mechanisms of action.Pages 18986-1899914 page(s)application/pdfenCreative Commons Attribution-NonCommercial 4.0 InternationalArticle - Refereedhttps://doi.org/10.1039/d5ra02702k1524Santos, Webster [0000-0002-4731-8548]Yang, Zhaomin [0000-0002-2044-6793]404762372046-2069