Fig. 3.

BetT1 and BetT3, but not CbcXWV, are involved in early choline uptake. Uptake of 1 mM [¹⁴C]choline by P. aeruginosa PA14 and various mutants is shown. Cells were grown in MOPS-P, incubated for 6 h in the presence or absence of 20 mM choline as an inducer, washed three times in an isomolar medium (M9 without glucose), and evaluated for uptake in MOPS-P containing 20 mM glucose in a 5-min assay. Black bars represent uninduced cultures, and white bars represent cultures preinduced with choline. Values are mean initial uptake rates ± standard errors of the means (n = 3 or 6).