Skip to main content
. Author manuscript; available in PMC: 2017 Mar 13.
Published in final edited form as: J Am Chem Soc. 2017 Jan 27;139(5):1900–1911. doi: 10.1021/jacs.6b11324

Figure 6. The catalase activity of coproheme decarboxylase is strongly enhanced in the Lys149Ala and Tyr145Ser mutants.

Figure 6

(A) The progress of the coproheme decarboxylase reaction over time [coproheme (red), harderoheme III (green), heme b (blue)] measured previously22 is shown superimposed on the time course for O2 production (orange) (10 μM enzyme-coproheme, 120 μM H2O2, 50 mM KPi, pH 7.4, 25 °C). The generation of ~10 μM O2 via the catalase reaction suggests that ~20 μM H2O2 was consumed during the same time window in which coproheme converted to heme b. (B) Initial rates of O2 production were measured as a function of [H2O2] and fit to eqn (5) for the WT (black), Tyr145Ser (cyan), and Lys149Ala (purple) decarboxylases. The resulting steady state parameters describing catalase activity are tabulated in the inset.