Metallo-β-lactamase–producing Enterobacterales: cyanide-containing efflux pump inhibitors as potential dual-activity inhibitors

CCCP, FCCP and KCN exhibited inhibitory activity against VIM-1-like MBLs, restoring imipenem susceptibility in E. coli at very low concentrations (0.04-19.55 µM). Thus, certain efflux pump inhibitors, as well as the gaseous biological mediator cyanide, have a novel action as inhibitors of MBL enzymatic activity, which, in turn, renders them potentially useful as adjunct antibacterial agents.