Figure 5.

Accumulation of [³H]l-alanine (60 Ci mmol⁻¹) in the l-alanine-loaded inverted membrane vesicles under an uphill solute potential. Inverted membrane vesicles were prepared from MLA301ΔalaE/pAlaE and MLA301ΔalaE. The extravesicular l-alanine concentration for the transport assay was 0.34 μmol/L. Transport assays were performed without NADH (A) and with 2.5 mmol/L NADH (B). Dotted line in (B) shows AlaE-mediated l-alanine accumulation obtained by subtracting the values in MLA301ΔalaE from those in MLA301ΔalaE/pAlaE in the presence of NADH. Values presented are the means of three independent experiments with standard deviations. Symbols: ○, MLA301ΔalaE/pAlaE; ●, MLA301ΔalaE.