FIG 4.

Role of PrpA in pellicle and biofilm formation in response to illumination at 24°C. (A) Pellicle formation by the parental strain (17978) and the prpA insertion mutant (prpA) on the surface of SB cultures statically incubated at 24°C in darkness. (B) Biofilm formation by the same two strains and the complemented prpA derivative (prpA.CV) on microtiter plate wells statically incubated at 24°C under darkness or illumination. Horizontal bars identify statistically different values (**, P ≤ 0.01; ***, P ≤ 0.001), and error bars represent the standard errors of each data set.