Figure 1.

High-throughput screening for BrpR inhibitors. (A) A schematic demonstration of high-throughput screening of small molecules. An E. coli reporter strain contains pJN1601 expressing BrpR under arabinose-inducible promoter P_BAD and pSH2103 carrying the luxCDABE genes under BrpR-repressible promoter P_{VV1_2288}. RLUs of the reporter strain were observed after the 20 μM addition of small molecules. (B–D) Each bar represents the RLU of E. coli containing pJN1601 and pSH2103 (B), V. vulnificus containing pSH2103 (C), and V. vulnificus containing pJN1606 carrying the luxCDABE genes under BrpR-inducible promoter P _brpT (D) in the presence of hit molecules as indicated. Error bars represent the SD from biological triplicates. Statistical significance was determined by the student’s t-test (^*p < 0.05, ^**p < 0.005, and ^***p < 0.0005; ns, not significant). Positive, RLUs from E. coli without arabinose (B) or V. vulnificus JN111 brpR mutant (C,D); negative, RLUs from E. coli with arabinose (B) or V. vulnificus JN111 (C,D); RLU, relative luminescence unit.