Fig. 3. Comparison of the bioactivity associated with the PQS probe 10, the HHQ probe 11, and the negative control 12 with native PQS and HHQ in stimulating PqsR-dependent transcription from the PqsA promoter (left panel) and in promoting PqsR-independent production of pyoverdine (right panel). Percentage PqsA:LacZ transcription was compared relative to 60 nM PQS for the PQS probe 10 (black bar), and to 1 μM HHQ for the HHQ probe 11 (grey bar) and negative control probe 12. ± Represents standard deviation of three independent biological replicates.