Fig. 2.

Time course of intracellular (A) and extracellular (B) concentrations of l-alanine. Cells of the Ala-Ala-hypersensitive mutant LAX12 harboring pSTV29 (open circles), pYeaS (solid circles), pYddG (solid triangles), pYtfF (solid squares), or pYgaW (solid diamonds) and MLA301 harboring pSTV29 (open triangles) were incubated in minimal medium containing 6 mM Ala-Ala. The intra- and extracellular fractions were recovered by the silicone oil method at the time intervals indicated. l-Alanine in both fractions was determined by high-performance liquid chromatography. Data are means of results from two (LAX12 harboring pSTV29, pYddG, or pYgaW and MLA301 harboring pSTV29) or three (LAX12 harboring pYeaS or pYtfF) independent experiments. Vertical bars indicate the standard errors of the means.