Antibacterial Discovery via Phenotypic DNA-Encoded Library Screening.

The global rise of multidrug resistant infections poses an imminent, existential threat. Numerous pipelines have failed to convert biochemically active molecules into bona fide antibacterials, owing to a lack of chemical material with antibacterial-like physical properties in high-throughput screening compound libraries. Here, we demonstrate scalable design and synthesis of an antibacterial-like solid-phase DNA-encoded library (DEL, 7488 members) and facile hit deconvolution from whole-cell Escherichia coli and Bacillus subtilis cytotoxicity screens. The screen output identified two low-micromolar inhibitors of B. subtilis growth and recapitulated known structure-activity relationships of the fluoroquinolone antibacterial class. This phenotypic DEL screening strategy is also potentially applicable to adherent cells and will broadly enable the discovery and optimization of cell-active molecules.