title: Synthesis and evaluation of inhibitors of bacterial drug efflux pumps of the major facilitator superfamily.
abstract: Inhibitors of drug efflux pumps have great potential as pharmacological agents that restore the drug susceptibility of multidrug resistant bacterial pathogens. Most attention has been focused on the discovery of small molecules that inhibit the resistance nodulation division (RND) family drug efflux pumps in Gram-negative bacteria. The prototypical inhibitor of RND-family efflux pumps in Gram-negative bacteria is MC-207,110 (Phe-Arg-β-naphthylamide), a C-capped dipeptide. Here, we report that C-capped dipeptides inhibit two chloramphenicol-specific efflux pumps in Streptomyces coelicolor, a Gram-positive bacterium that is a relative of the human pathogen Mycobacterium tuberculosis. Diversity-oriented synthesis of a library of structurally related C-capped dipeptides via an Ugi four component reaction and screening of the resulting compounds resulted in the discovery of a compound that is threefold more potent as a suppressor of chloramphenicol resistance in S. coelicolor than MC-207,110. Since chloramphenicol resistance in S. coelicolor is mediated by major facilitator superfamily drug efflux pumps, our findings provide the first evidence that C-capped dipeptides can inhibit drug efflux pumps outside of the RND superfamily.
authors: Department of Chemistry, Brown University, 324 Brook Street, Providence, RI 02912, United States.
authors: Babajide O
authors: BO
authors: Okandeji
authors: Daniel M
authors: DM
authors: Greenwald
authors: Jessica
authors: J
authors: Wroten
authors: Jason K
authors: JK
authors: Sello
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000378:metabolism*; D002701:Chloramphenicol / Q000494:pharmacology*; D004151:Dipeptides / Q000737:chemistry* / Q000494:pharmacology*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D006801:Humans; D026901:Membrane Transport Proteins / Q000378:metabolism*; D048372:Streptomyces coelicolor / Q000187:drug effects* / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004151:Dipeptides; D026901:Membrane Transport Proteins; C419365:phenylalanine arginine beta-naphthylamide; D002701:Chloramphenicol