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Office, E.

Publications and source records attributed to Office, E..

2 recordsLinked to original sources

Discovery of a novel synergistic antimycobacterial combination targeting EfpA using large-scale chemical-genetics

The efficacies of all antibiotics against tuberculosis are eventually eroded by resistance. New strategies to discover drugs or drug combinations with higher barriers to resistance are needed. Previously, we reported the application of a large-scale chemical-genetic interaction screening strategy called PROSPECT to the discovery of new Mycobacterium tuberculosis inhibitors, which resulted in identification of the small molecule BRD-8000, an inhibitor of a novel target, EfpA. Leveraging the chemical genetic interaction profile of BRD-8000, we identified BRD-9327, another, structurally distinct small molecule EfpA inhibitor. We show that the two compounds are synergistic and display collateral sensitivity because of their distinct modes of action and resistance mechanisms. High-level resistance to one increases the sensitivity to and reduces the emergence of resistance to the other. Thus, the combination of BRD-9327 and BRD-8000 represents a proof-of-concept for the novel strategy of leveraging chemical-genetics in the design of antimicrobial combination chemotherapy in which mutual collateral sensitivity is exploited.\n\n\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC=\"FIGDIR/small/772459v2_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (34K):\norg.highwire.dtl.DTLVardef@18da0eaorg.highwire.dtl.DTLVardef@13f76eforg.highwire.dtl.DTLVardef@1996766org.highwire.dtl.DTLVardef@5398ef_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

New inhibitors of Mycobacterium tuberculosis identified using systems chemical biology

New antibiotics are needed to combat rising resistance, with new Mycobacterium tuberculosis (Mtb) drugs of highest priority. Conventional whole-cell and biochemical antibiotic screens have failed. We developed a novel strategy termed PROSPECT (PRimary screening Of Strains to Prioritize Expanded Chemistry and Targets) in which we screen compounds against pools of strains depleted for essential bacterial targets. We engineered strains targeting 474 Mtb essential genes and screened pools of 100-150 strains against activity-enriched and unbiased compounds libraries, measuring > 8.5-million chemical-genetic interactions. Primary screens identified >10-fold more hits than screening wild-type Mtb alone, with chemical-genetic interactions providing immediate, direct target insight. We identified > 40 novel compounds targeting DNA gyrase, cell wall, tryptophan, folate biosynthesis, and RNA polymerase, as well as inhibitors of a novel target EfpA. Chemical optimization yielded EfpA inhibitors with potent wild-type activity, thus demonstrating PROSPECTs ability to yield inhibitors against novel targets which would have eluded conventional drug discovery.

microbiology↗