FIGURE 6.

Effects of posttranslational modifications on structural and functional status of AtAPX1. Comparison of peroxidase and chaperone activity of AtAPX1 protein treated with (A) GSNO (50–1,000 μM) for 30 min at 25°C in dark (S-nitrosylation), (B) NaHS (0.01–100 μM) for 30 min at 4°C in dark (S-sulfhydration), and (C) SIN-1 (0.5–10 mM) for 1 h at 37°C in dark (tyrosine nitration). The activities of treated protein were compared to non-treated protein whose activity was set to 100%. The black bars represent peroxidase activity and gray bars represent chaperone activity. Data are means (±) standard deviation of three independent experiments. Different letters indicate significant differences at P < 0.05 between non-treated and treated protein samples by one-way ANOVA with Tukey’s test.