Table 1.

Values obtained from binding and stability experiments

	Isothermal titration calorimetry					Low affinity						Thermofluor
	High affinity
	Kd (μM)	ΔH (kcal/mol)	–TΔS (kcal/mol)	ΔG (kcal/mol)	N	Kd (μM)	ΔH (kcal/mol)	–TΔS (kcal/mol)	ΔG (kcal/mol)	N	n	Tm (°C)	n
Wild-type apo												39.56 ± 0.21	12
Wild-type + cAMP	0.06 ± 0.02	−7.64 ± 0.66	−2.36 ± 0.66	−10.00 ± 0.17	0.11 ± 0.006	0.69 ± 0.10	−14.30 ± 0.86	5.86 ± 0.78	−8.44 ± 0.09	0.60 ± 0.01	7	39.26 ± 0.20	12
Wild-type + cGMP	0.16 ± 0.02	−4.94 ± 0.61	−4.35 ± 0.61	−9.29 ± 0.05	0.11 ± 0.01	1.74 ± 0.23	−13.64 ± 1.38	5.75 ± 1.35	−7.89 ± 0.07	0.64 ± 0.02	6	38.95 ± 0.22	12
S672R apo												39.21 ± 0.22	12
S672R + cAMP	0.53 ± 0.10	−3.83 ± 0.99	−4.81 ± 0.90	−8.64 ± 0.12	0.15 ± 0.003	5.05 ± 0.56	−16.60 ± 0.60	9.34 ± 0.61	−7.25 ± 0.07	0.85 ± 0.02	8	39.70 ± 0.23	12
S672R + cGMP	0.88 ± 0.27	−4.55 ± 0.59	−3.81 ± 0.59	−8.36 ± 0.18	0.18 ± 0.003	9.95 ± 0.58	−19.03 ± −2.85	12.19 ± 2.85	−6.83 ± 0.04	0.85 ± 0.07	5	39.38 ± 0.19	12

The table summarizes the dissociation constants (K_d) in μM for comparison of the wild-type and mutant S672R, which were obtained by ITC. The stoichiometry of the interaction (N) and the associated thermodynamic parameters (ΔG, ΔH, and TΔS) obtained by fitting are also shown here. For ITC and thermofluor experiments, the number of replicates is represented by “n” and, for the latter, the melting temperature is represented by T_m. The values represent the mean ± s.e.m.