Figure 3.

Cyclic lipopeptides prevented biofilm formation and eradicated existing biofilms of Gram-negative and Gram-positive bacterial pathogens. Inhibition of biofilm formation was tested by immediately adding 4.4 μM (4 μg/mL) of each cyclic lipopeptide 1–3 into the flow-through medium of the flow cell apparatus, and subsequently monitoring biofilm formation for a total of 3 days. Eradication experiments involved growing biofilms untreated for two days before the addition of peptides into flow-through medium. After 3 days, all bacteria were stained green with stain Syto-9, while dead-bacteria were stained red with propidium iodide (merge shown as 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 (xy, yz and xz dimensions). (A to C) shows inhibition of biofilm formation. (D–F) shows eradication of preformed biofilms. (G) shows untreated bacteria.