TABLE II.
pKa values and Hill coefficients of ionizable residues in CTX A5.
| pKa | Hill coefficient | |||||
|---|---|---|---|---|---|---|
| Titratable residue | PHREM1 | PHMD2 | Expt. | PHREM1 | PHMD2 | Expt. |
| His4 | 4.5 (0.5) | 4.7 (0.5) | 5.6 | 1.02 (0.16) | 1.20 (0.81) | - |
| 4.5 (0.5) | 4.6 (0.5) | 0.81 (0.26) | 0.60 (1.01) | |||
| 4.5 (0.1) | 4.7 (0.1) | 0.87 (0.07) | 0.75 (0.07) | |||
| Glu17 | 3.8 (0.2) | 3.9 (0.3) | 4.0 | 0.93 (0.11) | 0.99 (0.27) | - |
| 3.8 (0.2) | 3.9 (0.3) | 0.87 (0.12) | 0.87 (0.30) | |||
| 3.8 (0.1) | 3.9 (0.1) | 0.89 (0.07) | 0.91 (0.07) | |||
| Asp42 | 2.3 (0.7) | 1.0 (1.9) | 3.2 | 0.89 (0.23) | 2.76 (3.39) | - |
| 2.3 (0.7) | 1.8 (2.0) | 0.64 (0.34) | 0.60 (4.02) | |||
| 2.3 (0.2) | 1.8 (0.2) | 0.62 (0.06) | 0.64 (0.12) | |||
| Asp59 | 1.3 (0.7) | 1.0 (1.3) | <2.3 | 0.92 (0.22) | 2.80 (2.60) | - |
| 1.3 (0.7) | 1.4 (1.4) | 0.64 (0.36) | 0.72 (3.33) | |||
| 1.4 (0.2) | 1.4 (0.3) | 0.68 (0.11) | 0.73 (0.11) | |||
1
Results obtained from the PHREM simulations.
2
Results obtained from the PHMD simulations.
Upper, middle and lower values for each residue are calculated with Method I, Method II and Method III, respectively. Estimated errors are indicated in the brackets.