Table 5.

Summary of activation parameters for dissociation of protein ligand complexes^a

Variant/ ligand	koff(s−1)	ΔG‡ (kcal/mole)	ΔH‡b (kcal/mole)	-TΔS‡ (kcal/mole)
biotin
wt	0.33 ± 0.01	17.7 ± 0.4	22.9 ± 0.8	−5.1 ± 0.5
G115S	80 ± 20	14.5 ± 0.4	16 ± 2	−2 ± 2
R118G	29 ± 5	15.3 ± 0.3	24.4 ± 0.6	−9.1 ± 0.6
R119W	0.49 ± 0.04	17.7 ± 0.1	24.1 ± 0.8	−6.4 ± 0.4
bio-5`-AMP
wt	0.00027 ± .00003	22.0 ± 0.1	20 ± 4	4 ± 1
G115S	0.84 ± 0.03	16.9 ± 0.6	7 ± 1	10 ± 1
R118G	0.142 ± 0.006	18.4 ± 0.1	16 ± 3	2 ± 3
R119W	0.00009 ± 0.00001	22.3 ± 0.1	20 ± 2	−0.3 ± 1

^a Activation energies and entropies are given at 20°C.

^b For the Eyring analysis, measurements were performed in Standard Buffer (10 mM Tris-HCl, 200 mM KCl, 2.5 mM MgCl₂, pH 7.50 ± 0.01 at the working temperature) at temperatures ranging from 10 to 35°C. Data were obtained at 5° intervals.