Figure 8

NADPH-dependent peroxidase activity of EcAhpC and C-terminal variants.

(A) Active site of a typical FF active site of reduced StAhpC, where the C-terminal tail folds into the active site and forms weak interactions with the active site residues. The residues S86 and T88 hold the C-terminal tail through hydrogen bond interactions with I187′. (B) NADPH oxidation of wild type EcAhpC and its C-terminal variants at 30 μM of H₂O₂ is shown as a representative of other measurements done with different concentrations of H₂O₂. The background oxidation of EcTrxR and EcTrx without EcAhpC is taken as a control. Michaelis-Menten plots for (C) EcAhpC_I187G, (D) EcAhpC_S86A,T88A, (E) EcAhpC_1–172 were done with various concentrations of H₂O₂.