FIG 5.

The ΔkatA mutant exhibits a defect in biofilm EPS production. (A to D) Representative SEM images of 20-h biofilms formed by the WT (A), the ΔkatA mutant (B), the WT plus bovine catalase (C), and the ΔkatA mutant plus bovine catalase (D). (E to G) The WT (black circles) and ΔkatA mutant (white circles) were incubated for 20 h with aeration or kept stationary to generate planktonic suspensions (PS) and biofilm (BS) suspensions. EPS was further extracted from the biofilm suspension to generate a cellular fraction (CF) and EPS fraction (EF) for measurement of eDNA (E), protein (F), and carbohydrate (G). Box and whisker plots display the combined data from 3 independent experiments with 3 technical replicates each. ***, P < 0.001 (by two-way ANOVA with Sidak’s test for multiple comparisons).