Table 3. Affinity of AkCBM42 to oligosaccharide estimated by ITC.
| Protein | Ligand | Ka(×103 M−1) | ΔG (kcal·mol−1) | ΔH (kcal·mol−1) | TΔS (kcal·mol−1) | na | Mtotb (mM) | c |
|---|---|---|---|---|---|---|---|---|
| E221A | mA1 | 1.6 (±0.05)c | −4.4 | −5.0 (±0.05) | −0.6 | 2.0 | 0.6 | 1.9 |
| E221A | A3 | 2.7 (±0.2) | −4.7 | −3.6 (±0.09) | 1.1 | 2.0 | 0.4 | 2.1 |
| E221A | mX1 | NDd | ND | ND | ND | ND | ||
| E221A | X3 | ND | ND | ND | ND | ND | ||
| E221A | glucose | ND | ND | ND | ND | ND | ||
| E221A/D435A | mA1 | 8.3 (±0.3) | −5.4 | −1.0 (±0.01) | 4.4 | 1.0 | 0.2 | 1.7 |
| E221A/D488A | mA1 | 1.3 (±0.02) | −4.2 | −3.0 (±0.02) | 1.2 | 1.0 | 0.3 | 0.4 |
| E221A/D435A/D488A | mA1 | ND | ND | ND | ND | ND | ||
| E221A/D435A/D488A | A3 | ND | ND | ND | ND | ND |
aNumber of binding sites on the protein. The values were fixed for curve fitting.
bThe total protein concentration in the cell.
cValues in parentheses are S.D. from the fit.
dND, not detected.