(a) Annexin V and PI staining of S. cerevisiae after C816 treatment for 10 and 24 h. Green: Annexin V. Red: PI. After 10 h only Annexin V staining is observed. PI staining is observed but after 24 h of treatment. Scale bar = 10 µm (b) Apoptosis determination by flow cytometry in S. cerevisiae after C816 treatment for 10 h. The toxin induced a dose dependent increase in Annexin V stained cells. Representative results are shown. (c) Quantification of Annexin V positive cells detected by flow cytometry. * Significant differences respect to control p < 0.01, n = 3. (d) Survival plating assay for cells treated as those analyzed by flow cytometry. After C816 treatment for 10 h, cells were serially diluted, plated and incubated at 30 °C. Colonies were counted after 48 h. * Significant differences respect to control p < 0.01, n = 3, ** significant differences respect to control p < 0.05, n = 3.