Table IV.
Energetics of binding
| Carbohydrate | No. of Experiments | c Value | Stoichiometrya | Kass | ΔG0b | ΔH0b | TΔS0b |
|---|---|---|---|---|---|---|---|
| 103m−1 | kcal/mol | kcal/mol | kcal/mol | ||||
| Manc | 4 | 3.8 | 0.90 | 1.9 | −4.4 | −6.3 | −1.9 |
| ManαMec | 3 | 5.4 | 0.95 | 3.4 | −4.8 | −6.5 | −1.7 |
| Manα(1–2)Manc | 3 | 13.0 | 0.92 | 15.4 | −5.7 | −7.0 | −1.3 |
| Manα(1–3)[Man(α1–6)]Manc | 3 | 1.4 | 0.95 | 5.6 | −5.1 | −7.1 | −2.0 |
| Manα(1–3)[Manα(1–3)[Manα(1–6)]Manα(1–6)]Man (Man-5) | 3 | 2.3 | 0.95 | 6.6 | −5.2 | −8.7 | −3.5 |
| Man-9 | 2 | 2.8 | 1.0d | 23 | −5.8 | −4.8 | 1.1 |
| Soybean agglutinin | 2 | 11.2 | 0.93 | 80 | −6.7 | −4.8 | 1.9 |
a
Obtained from fitting the ITC data. The reported values for Kass, ΔG0, ΔH0, and TΔS0 are determined with n fixed at 1.0. These values do not differ significantly from those obtained when treating the number of binding sites as a variable.
b
The errors on ΔG0 and ΔH0 are of the order of magnitude of 0.1 kcal/mol while for TΔS0 they are 0.2 kcal/mol.
c
Taken from Buts et al. (2006) and included for comparison.
d
As the correct concentration of Man-9 could not be determined sufficiently accurately (due to availability of sufficient material) the number of binding sites was kept fixed at 1.0 in accordance with the data obtained from Man5 and soybean agglutinin.