Fig. 4: Outer membrane charge is unaffected in ∆cydAB biofilm cells.

Outer membrane charge was investigated by measuring the binding of cationic cytochrome c to planktonic and biofilm cells. Data were analyzed by a two-tailed unpaired t-test. Data are representative of at least three biological replicates, and are presented as mean ± SEM. Each dot represents a biological replicate. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.