Fig. 3.

Effect of polyP3 on the growth and biofilm formation of the four bacterial species in a mixed culture. (A) To assess the total growth (planktonic and biofilm bacterial growth), the biofilm bacterial cells were dispersed, mixed thoroughly with planktonic bacterial cells, and OD₆₀₀ of the suspension was measured. The suspension was diluted 2 to 10 times, and OD₆₀₀ of the diluted suspension was also measured. The amount of biofilm formed by the mixed bacterial species was quantitated by crystal violet staining. Readings were expressed as mean %OD₆₀₀ (%OD₆₀₀ = OD₆₀₀ ∕ mean OD₆₀₀ of control × 100). One-way ANOVA with Tukey’s post-hoc tests p < 0.001, versus control (0% polyP3). (B) SEM images of the biofilms at a magnification of 20 000 × (left) and 100 000 × (right).