. Author manuscript; available in PMC: 2014 Aug 28.

Published in final edited form as: J Am Chem Soc. 2013 Aug 15;135(34):10.1021/ja405725f. doi: 10.1021/ja405725f

Table 1.

Square-scheme Rate Constants from the Reduction of K79H Variants of Iso-1-Cytc by Co(terpy)₂²⁺.

pH	k_ET^a (mM⁻¹ s⁻¹)	Direct ET intercept^a (s⁻¹)	k_b^b (s⁻¹)	k_f^b (s⁻¹)	k_ET(Alk)^b (mM⁻¹ s⁻¹)
WT*K79H
5.0	6.8 ± 0.1	0.4 ± 0.4	0.49 ± 0.02	0.9 ± 0.2	0.038 ± 0.003
5.5	7.3 ± 0.2	1.2 ± 0.6	0.50 ± 0.02	1.2 ± 0.2	0.029 ± 0.003
6.0	10.0 ± 0.4	1.0 ± 1.5	0.52 ± 0.02	2.1 ± 0.4	0.027 ± 0.004
6.5	11.1 ± 0.2	4.6 ± 0.7	0.56 ± 0.02	3.5 ± 0.4	0.024 ± 0.004
7.0	13.6 ± 0.7	10 ± 2	0.57 ± 0.03	4.1 ± 0.6	0.037 ± 0.005
7.5	14.4 ± 1.0	14 ± 3	0.61 ± 0.04	4.5 ± 0.9	0.047 ± 0.008
8.0	13.3 ± 1.3	19 ± 4	0.70 ± 0.08	6.8 ± 1.8	0.045 ± 0.012

yK79H
5.0	6.0 ± 0.2	−0.1 ± 0.4	0.542 ± 0.003	1.07 ± 0.02	0.024 ± 0.001
7.5	9.7 ± 0.7	9 ± 2	0.76 ± 0.03	4.0 ± 0.3	0.013 ± 0.004

Reported errors are the standard error of parameters obtained from a fit of k_obs,1 versus Co(terpy)₂²⁺ concentration to a linear equation, as reported by SigmaPlot.

Reported errors are the standard error of parameters obtained from a fit of k_obs,2 versus Co(terpy)₂²⁺ concentration to eq 4, as reported by SigmaPlot.