Figure 3.

Potassium permanganate does not strongly stain biofilm eDNA. Pseudomonas aeruginosa PittD biofilm stained with BacLIght LIVE/DEAD and KMnO₄. (A) The green signal from the Syto 9 shows brightly stained individual bacterial rods (a representative group indicated by the white filled arrow and two cells inside the white circle) as well as diffuse, less intense, staining between the cells (light and dark green arrows indicate less and more intense areas of diffuse staining, respectively). The diffuse staining surrounding cells is consistent with that of eDNA. (B) The blue reflected signal from the KMnO₄ shows a weak reflected signal in these same areas, but shows strong signal in areas where there are no significant amounts of eDNA (blue arrows). There is a weak reflected signal from the individual cells (white circle). (C) Overlay of the two images show the eDNA and KMnO₄ staining are not colocalized. Images A and B are raw tiff files.