Table 1 Binding parameters of FL1-BP and FL2-BP to mono- and difucosyllactose determined by ITC and SPR analysis.

Binding parameters of FL1-BP and FL2-BP to mono- and difucosyllactose determined by ITC and SPR analysis..

ProteinLigandITC*SPR
Ka
(×105 M−1)
Kd
(μM)
ΔG0
(kcal mol−1)
ΔH
(kcal mol−1)
TΔS0
(kcal mol−1)
ΔS0
(cal K−1 mol−1)
n
(site)
Kd
(μM)†
Rmaxχ 2 §
FL1-BP2′-FL1.05 ± 0.239.75−6.8−23.6 ± 0.516.8−56.30.85 ± 0.149.0 ± 0.714.70.09
FL2-BP2′-FL1.86 ± 0.125.40−7.2−14.2 ± 0.77.0−23.60.90 ± 0.049.9 ± 1.69.30.13
3-FL1.69 ± 0.115.95−7.1−14.0 ± 0.46.9−23.21.12 ± 0.145.9 ± 0.510.20.06
LDFT0.05 ± 0.00191.11−5.1−6.8 ± 0.51.7−5.71.02 ± 0.02163.1 ± 25.012.00.24

*Values of association constants (Ka), enthalpy of binding (ΔH), and binding stoichiometry (n) obtained in ITC analysis are expressed as means ± SD of duplicate experiments. Dissociation constants (Kd) were calculated from the reciprocal of Ka. The Gibbs free energy change (ΔG0) and the entropy change (ΔS0) were calculated from the equations ΔG0 = −RTlnKa and TΔS0 = ΔH − ΔG0, respectively (R, gas constant; T, absolute temperature).

†The Kd values obtained in the SPR analysis are means ± SD of duplicate experiments.

‡The maximum binding level from the fits to a one-site binding model.

§Statistical goodness of the fit to a one-site binding model.