FIGURE 6.
Inhibition of RTA and Stx2 by pteroic acid (PTA) and 8-methyl-9-oxoguanine (9OG). Yeast ribosomes (7 pmol) were incubated with RTA or Stx2 at 1 nM for 5 min at 30°C in the presence of PTA at final concentrations of 3.3, 10, 30, 89, 266, and 800 μM or with RTA at 1 nM in the presence of 9OG at 12, 37, 111, 333, and 1000 μM. rRNA was extracted, precipitated, and equal amounts were used in qRT-PCR. The fold increase in depurination relative to the no inhibitor reactions was determined by the comparative CT method and used to set the activity for each toxin to 100%. RTA and Stx2 inhibition by PTA is depicted with closed diamonds and open circles, respectively. RTA inhibition by 9OG is depicted with open triangles. Data are the mean ±SD of triplicate reactions.