Figure 6.

Effect of CCCP and DCCD on the accumulation of [³H]l-alanine in the l-alanine-loaded inverted membrane vesicles under an uphill solute potential. [³H]l-alanine accumulation was determined after 5 min of incubation as described in Materials and Methods. The AlaE-mediated [³H]l-alanine (38 Ci mmol⁻¹) accumulation was calculated by subtracting values obtained with MLA301ΔalaE vesicles from those in MLA301ΔalaE/pAlaE in the presence of NADH. Solid black bar, control; hatched bar, 20 μmol/L CCCP; solid gray bar, 50 μmol/L DCCD. Values presented are the means of three independent experiments with standard deviations (unpaired Student t-test, **<0.001).