Fig. 6: Kinetic studies of the oxidation of 6 by 1 catalyzed by 2. [Se] = 2^.[2].

All experiments were conducted in 1 M Tris pH 7.5, at 25 °C. a Dependence of the reaction rate from [Se]. [1] = 7.5 mM, [6] = 5 mM, [Se] = 0.1–1 mM. The dependence in logarithmic coordinates was fit linearly by equation y = a + bx; a = −3.0 ± 0.2, b = 0.84 ± 0.02. b Dependence of the reaction rate on the concentration of 6 in experiments with different [Se] concentrations. [1] = 7.5 mM, [6] = 0.5–10 mM, [Se] are shown above each graph. Data for each set were fitted by equation r = V_max^.S/(K_M + S): [Se] = 0.05 mM, V_max = 1.5 ± 0.1·10⁻⁵M s⁻¹, K_M = 7.8 ± 1.6·10⁻⁴ M; [Se] = 0.1 mM, V_max = 2.8 ± 0.2·10⁻⁵M s⁻¹, K_M = 11 ± 1.6·10⁻⁴M; [Se] = 0.2 mM, V_max = 4.5 ± 0.2·10⁻⁵M s⁻¹, K_M = 8.4 ± 1.5·10⁻⁴M. (See Supplementary Fig. 11 for the full range of [Se].) c Dependence of the reaction rate on the concentration of 6 in experiments with different concentrations of 1. [Se] = 0.2 mM, [6] = 0.5–10 mM, [1] is shown above each graph. Data for each set were fitted by equation r = V_max^.S/(K_M + S): [1] = 3 mM, V_max = 1.9 ± 0.1·10^-5M s⁻¹, K_M = 3.8 ± 0.8^.10^-4M; [1] = 7.5 mM, V_max = 4.5 ± 0.2^.10⁻⁵ M s⁻¹, K_M = 8.4 ± 1.5·10⁻⁴M; [1] = 12 mM, V_max = 6.9 ± 0.3·10⁻⁵M s⁻¹, K_M = 14.5 ± 1.0·10⁻⁴M. d Inhibition of the reaction by [9]. [1] = 7.5 mM, [6] = 5 mM, [Se] = 0.2 mM, [9] = 0–100 mM. Data were fitted by equation y = 2.2·10⁻⁷/(0.006 + ax), a = 0.11 ± 0.01. Error bars in all plots represent standard deviations based on three independent experiments.