Extrusion of drugs or drug-like compounds through bacterial efflux pumps is a serious health
issue that leads to loss in drug efficacy. Combinatorial therapies of low-efficacy drugs with
efflux pump inhibitors may help to restore the activities of such drugs. In this quest, natural
products are attractive molecules, since in addition to their wide range of bioactivities they
may inhibit efflux pumps. The current work repurposed the bioactive alkaloid roemerine as a
potential efflux pump inhibitor. In Bacillus subtilis, both Bmr and BmrA, belonging to the …