FIG 3.

Effects of Ptr2 mutations on cell growth. 3HA-tagged wild-type or Ptr2 mutant proteins were expressed in ptr2Δ cells. The cells were incubated at 25°C for 20 h in SD (40 μg · ml⁻¹ tryptophan) (A), Ala-Trp medium containing 20 or 100 μg · ml⁻¹ Ala-Trp in the absence of free tryptophan (B), or Leu-Trp medium containing 23 μg · ml⁻¹ Leu-Trp in the absence of free tryptophan (C). The starting OD₆₀₀ value was 0.04.