Figure 2.

FGE_4C‐catalyzed product formation as a function of time (○) in reactions containing 0.5 μm FGE_4C, 200 μm substrate, 0.5 μm CuSO₄, 2 mm DTT, 50 mm EDTA, 50 mm NaCl and 50 mm Tris (pH 8). The reaction mixtures were supplemented with 5 μm A) FGE_S266A, B) FGE_C274S, C) FGE_C269S, D) BSA, or E) FGE_S290K, one minute after initiation with FGE_4C (▴). In A), ▴ data were fitted to the function [P]=A(1−exp(−k ${}_{\mathrm{off},\mathrm{Cu}{}^{\mathrm{I}}}$ t))+m ₁ t (—), and the ○ data were fitted to [P]=m ₂ t (‐ ‐ ‐ ‐), where A is the concentration of product formed until Cu^I redistribution between FGE_4C and FGES_266A is complete (4.0 μm), k ${}_{\mathrm{off},\mathrm{Cu}{}^{\mathrm{I}}}$ is the rate at which the FGE_4C:Cu^I complex decays (0.07 min⁻¹), m ₁ is the residual activity after Cu^I redistribution (m ₁/[FGE_4C]=0.05 min⁻¹), and m ₂ is the activity of Cu^I‐complemented FGE_4C (m ₂/[FGE_4C]=0.8 min⁻¹). The data are averaged values from two or more independent experiments.