Fig. 5.

Chemical complementation in yeast and human hepatoma cells. (a) Relative resistance of M to 2 mM atenolol and 10 μM cisplatin and relative resistance of Y to 4 mM lithium chloride in media supplemented with water (red), 1 mM cysteine (green), and 1 mM glutathione (yellow). Resistance of Y is set to 1 for atenolol and cysteine and to 0.08 for lithium chloride. (b) Resistance of HepG2 cell lines to 4 mM atenolol, 32 μM cisplatin, and 60 mM lithium chloride after 48 h of growth in media supplemented with water (red) and 20 mM l-cysteine (green). Resistance is measured by OD₅₇₀ from an MTT assay, which is proportional to the number of viable cells.