FIG. 5.

Treatment of P. aeruginosa biofilms with EDTA and divalent cations. Spinning disk reactor biofilms of P. aeruginosa PAO1 were treated for 24 h at 37°C. (Top) Total (planktonic plus biofilm) viable counts. (Bottom) Percentage of viable cells present in the biofilm (gray) or the planktonic phase (white). Treatments were PBS alone or PBS plus EDTA (50 mM), EDTA-Ba (50 mM), EDTA-Mg (50 mM), EDTA-Ca (50 mM) or EDTA-Fe (50 mM). The viable cells, which remained attached to the disks after the treatment, were counted as biofilm cells. The viable planktonic cells were the detached cells in suspension in the treated wells. Data are means from two disks from each of two spinning reactors. Error bars, standard deviations.