Structure-Based Development of (1-(3'-Mercaptopropanamido)methyl)boronic Acid Derived Broad Spectrum, Dual-Action Inhibitors of Metallo- and Serine-β-lactamases

The emergence and spread of bacterial pathogens acquired metallo-beta-lactamase (MBL) and serine-beta-lactamase (SBL) medicated beta-lactam resistance gives rise to an urgent need for the development of new dual-action MBL/SBL inhibitors. Application of a pharmacophore fusion strategy led to the identification of (2'S)-(1-(3'-mercapto-2'-methylpropanamido)methyl)boronic acid (MSO1) as a new dual-action inhibitor, which manifests broad-spectrum inhibition to representative MBL/ SBL enzymes, including the widespread VIM-2 and KPC-2. Guided by the VIM-2:MS01 and KPC-2:MS01 complex structures, further structural optimization yielded new, more potent dual-action inhibitors. Selectivity studies indicated that the inhibitors had no apparent inhibition to human angiotensin-converting enzyme-2 and showed selectivity across serine hydrolyases in E. coli and human HEK293T cells labeled by the activity-based probe TAMRA-FP. Moreover, the inhibitors displayed potentiation of meropenem efficacy against MBL- or SBL-positive clinical isolates without apparent cytotoxicity. This work will aid efforts to develop new types of clinically useful dual-action inhibitors targeting MBL/SBL enzymes.