Fig. 3. Gene expression and pyocyanin production in P. aeruginosa. (a) Effect of compounds 1 (10 μM) and 3 (100 μM) on the gene expression of las-controlled genes in P. aeruginosa. Gene expression of lasA in the presence of non-irradiated compound 3, λ = 365 nm irradiated 3 and compound 1 in the ΔlasI (gray) and ΔlasRI (black) strains. All samples are compared to the control sample. Data is plotted as mean and standard deviation of two biological replicates each performed in duplo. (b) The effect of compounds 1 (50 μM) and 3 (2 × 50 μM) on pyocyanin production in cultures of P. aeruginosa ΔlasI before and after λ = 365 nm light-irradiation. Data is plotted as mean and standard deviation of three experiments consisting of two biological replicates.