Figure 4

Reporter assays of PLuxR-GFP. The results show the changes in the fluorescence intensities of the cultures with pSB-GFP, Placq-GFP, or PLuxR-GFP dependent on the input of 4.5 nM AHL. Cells were cultured for 8 hours after the induction. In the presence of AHL, the culture with PLuxR-GFP showed 6.8-fold higher fluorescence intensity than that in the absence of AHL. The culture with pSB-GFP, which does not express GFP, was used as a negative control. The culture with Placq-GFP, which constitutively expresses GFP, was used as a positive control. The assays were performed in triplicate. Error bars indicate the standard deviation.