Fig. 4

Membrane permealization. P. aeruginosa cells were exposed to 4× MIC of TP359 for 4 h. Cultures were centrifuged at 2000 × g for 10 min, pellets were washed, incubated and re-suspended in 0.85 % NaCl. Cells were then incubated in the dark for 45 min in a 2× stock solution of the baclight staining reagent before fluorescence was captured by the Nikon Eclipse TE200. a and d show untreated mucoid and non-mucoid P. aeruginosa, respectively; b and e show TP359 treated mucoid and non-mucoid P. aeruginosa, respectively. Images are representatives of separate experiments. For c and f random portions were selected for both treated and untreated samples using the NIS element 3.1 software and counted before extrapolating the percentage of damaged membranes in the mucoid and non-mucoid strains of P. aeruginosa, respectively. This data is a representative of three separate experiments and significance was established at *P < 0.05 and **P < 0.01