Figure 7.

Sensitivity of NcAA9C and LsAA9A for oxidative damage. The graph shows product levels obtained after a 2 min reaction containing 1 mM AscA and various amounts of H₂O₂. Reaction mixtures containing 1 μM LsAA9A (purple) or 1 μM NcAA9C (blue), 1 mM Glc₅, and varying H₂O₂ concentrations (25–1000 μM) were pre-incubated for 1 min, after which the reaction was started by adding the reductant. In reactions not showing signs of enzyme inactivation, product levels were slightly higher than the amount of added H₂O₂ due to the combination of AscA-mediated H₂O₂ generation and a small systematic error in the concentration of the H₂O₂ stock solution.