Table 2.
pKa values for RNase Sa and its 5K mutant
| Residue | RNase Sa measured | RNase Sa estimated | 5K variant measured | 5K model estimated | 5K crystal estimated |
|---|---|---|---|---|---|
| Asp01 | 3.44 | 2.6 | Lys | Lys | Lys |
| Asp17 | 3.72 | 3.9 | Lys | Lys | Lys |
| Asp25 | 4.87 | 3.8 | Lys | Lys | Lys |
| Asp33 | 2.39 | 1.5 | 2.12 | 1.5 | 2.1 |
| Asp79 | 7.37 | 5.2 | 6.06 | 5.2 | 5.1 |
| Asp84 | 3.01 | 1.1 | 2.98 | 1.1 | 1.1 |
| Asp93 | 3.09 | 2.4 | 3.00 | 2.4 | 2.4 |
| Glu14 | 5.02 | 4.1 | 2.83 | 4.1 | 4.1 |
| Glu41 | 4.14 | 4.5 | Lys | Lys | Lys |
| Glu54 | 3.42 | 2.5 | 2.26 | 2.5 | 4.2 |
| Glu74 | 3.47 | 4.5 | Lys | Lys | Lys |
| Glu78 | 3.13 | 2.9 | 3.02 | 2.8 | 2.6 |
| His53 | 8.27 | 6.3 | 7.39 | 6.3 | 7.2 |
| His85 | 6.35 | 7.0 | 6.09 | 7.0 | 6.4 |
| Tyr30 | 11.3 | 10.1 | n.d. | 10.1 | 10.0 |
| Tyr49 | 10.6 | 10.0 | n.d. | 10.0 | 9.9 |
| Tyr 51,52,55,80,81,86 | >11.5 | 11.3 (avg) | n d. | 11.3 (avg) | 11.3 (avg) |