Depolarization of P. aeruginosa membranes upon incubation with magainin 2, pre-elafin/trappin-2 or derived peptides. Fluorescence emission (arbitrary units) of the probe NPN inserted into the outer membrane (top panel) or the probe DiSC3 inserted into the inner membrane (bottom panel) of P. aeruginosa upon addition of the indicated peptides. The controls were performed in phosphate buffer alone. Pre-elafin/trappin-2 and elafin were used at 20 μM, cementoin at 100 μM and magainin 2 at 10 μM. The arrow indicates the time-point for the addition of the various peptides.