Figure 2.

A, Ca²⁺ tolerance assay of K667 mutant yeast-expressing vector alone (▴), sCAX1 (●), or lCAX1 (⋄). Yeast strains were grown in selection media overnight at 30°C and diluted to an optical density at 600 nm (OD₆₀₀) of 1.0, then inoculated into fresh yeast peptone dextrose (YPD) media containing a range of CaCl₂ concentrations from 100 to 200 mm. Yeast cells were grown for 16 h at 30°C in flat-bottomed 24-well dishes. Cell density was determined by measurements at OD₆₀₀. B, K667 yeast strains expressing vector alone, sCAX1, and lCAX1 were grown in selection media overnight at 30°C and diluted to an OD₆₀₀ of 1.5, then spotted onto YPD media alone and YPD media containing 200 mm CaCl₂. Yeast growth on YPD alone and YPD with 200 mm CaCl₂ was photographed after 1 and 3 d, respectively.