Fig. 4

Metal binding by yeast strains expressing chimeric proteins on the outer surface. (a) 5 × 10⁸ yeast cells of each indicated strain (parental (WT) or carrying the pYSD-6xHis plasmid), were used for Ni²⁺ binding experiments as described, and ICP-EOS assays were performed to quantify the nmoles of metal ions, reported in the graphs. The ratio between values of modified and parental strains (YSD/WT) is indicated for each strain. (b) Similar experiments were performed using double (10⁹) amount of yeast cells. (c) As in (a), 5 × 10⁸ yeast cells, either parental (WT) or carrying the pYSD-yCup1 plasmid, were used for Cu²⁺ binding experiments, and Cu²⁺ ions quantification data are presented as nmoles of Cu²⁺ normalized to mg of CDW. In all panels, each column represents the mean ± SEM of 5 independent experiments (n = 5; **p < 0,01, Mann Whitney T-test was applied for statistical analysis)