FIG 5.

Short-term treatments with combinations of low concentrations of peptide 1018 and ciprofloxacin still inhibited biofilm formation. Peptide 1018 (0.8 μg/ml) and ciprofloxacin (40 ng/ml) were injected for 2 h at the beginning of P. aeruginosa PA14 biofilm formation or into 2-day-old P. aeruginosa PA14 biofilms for 1 h on day 2 or for 1 h on day 2 plus 1 h on day 3. After 3 days, bacteria were stained green with the all-bacteria stain Syto-9 and red with the dead-bacteria stain propidium iodide (merge shows as a color change from yellow to red) prior to confocal imaging. Each panel shows reconstructions from the top in the large panel and sides in the right and bottom panels (x-y, y-z, and x-z dimensions, respectively). ATB, antibiotic (ciprofloxacin).