Figure 3.

Suppression of Cd²⁺ hypersensitivity of S. cerevisiae ycf1Δ mutant strain DTY167 by plasmid-borne AtPCS1. Yeast ycf1Δ strain DTY167 was transformed with pYES3-AtPCS∷FLAG (O) or empty pYES3 vector (●). Cells were grown at 30°C to an OD₆₀₀ of approximately 1.8 in AHC medium supplemented with glucose and tryptophan before aliquots were inoculated into 2-ml volumes of the same medium containing different concentrations of heavy-metal salts. OD₆₀₀ was measured after growth for 36 h. Similar growth assays in liquid media containing AsO₄³⁻, AsO₂⁻, Cu²⁺, or Hg²⁺ demonstrated that plasmid-borne AtPCS1∷FLAG increased the concentrations of these metal ions or their oxides required for 50% attenuation of cell density from 300, 200, 250, and 4 μM to 550, 325, 600, and 6.3 μM, respectively.