Table 2.

Thermodynamic Parameters for the IKKβ NBD (residues 735–745) and IKKβ C-Terminal Region (residues 680–756) Binding to NEMO (residues 38–196) As Measured by Isothermal Titration Calorimetry^a

IKKβ residues	N	KA (M−1)	KD (μM)	ΔG (kcal/mol)	ΔH (kcal/mol)	−TΔS (kcal/mol)
735–745	1.16 ± 0.30	2.84 ± 0.23 × 104	35	−6.07	−1.15 ± 0.40	−5.57
680–756	0.98 ± 0.04	9.38 ± 2.26 × 105	1	−8.17	−18.47 ± 1.07	10.30

^aStoichiometry (N), association constant (K_A), and enthalpy change (ΔH) are the mean values obtained from three independent ITC experiments. K_D was determined using the relationship K_D = K_A⁻¹. ΔG and −TΔS were determined from the relationship ΔG = −RT ln K_A = ΔH − TΔS.