FIGURE 5.

Effect of amino acid competitors on Pro and GABA uptake and OC8HSL degradation. A, uptake of 1 μm l-[³H]proline (left) and [³H]GABA (right) was assayed by the rapid filtration method in cultures of A. tumefaciens mutants atu2422(atu2422-F77A), atu2422(atu2422), and atu2422(6000). Competing solutes were added to a final concentration of 10 μm. B, the OC8HSL concentration (added at 400 nm) was measured in cell cultures grown in AB medium supplemented with GABA (0.1 mm) in the presence of competing solutes added at final concentration of 1 mm. Experiments were done in duplicate.