Table 2.
Experimental and calculated stability changes for mutations of the FBP WW domain that affect several structural elements
| Mutation | ΔGN,exp | ΔGN | ΔG1 | ΔG2 |
|---|---|---|---|---|
| W8F | 1.65 ± 0.16 | 2.39 | 0.21 | — |
| T13A | 0.81 ± 0.17 | 0.69 | 0.22 | — |
| T13G | 0.58 ± 0.22 | (1.28) | (0.56) | — |
| Y19A | 0.67 ± 0.13 | (2.65) | (1.60) | (1.01) |
| Y20F | 0.68 ± 0.18 | (−0.76) | (0.31) | (−0.45) |
| Y21A | 1.70 ± 0.10 | 2.58 | 0.56 | 1.42 |
| R24A | 0.78 ± 0.17 | (−0.23) | (−0.31) | (−0.38) |
| E27A | 1.02 ± 0.13 | (0.17) | — | (0.17) |
| T29G | 1.89 ± 0.11 | 1.47 | — | 1.14 |
| W30A | 0.76 ± 0.14 | 1.32 | — | 0.53 |
| L36A | 0.91 ± 0.14 | 0.47 | — | −0.30 |
| L36V | 0.53 ± 0.14 | (0.23) | — | (−0.34) |
Experimental data for the stability changes ΔGN,exp are from Petrovich et al. (33). The stability changes ΔGN, ΔG1, and ΔG2 for the whole protein and hairpin 1 or 2, respectively, have been calculated with the program FOLD-X (65,66). For mutations to alanine (A) or glycine (G) and the mutation W8F, native structures for the mutant proteins have been generated by truncation of atoms. For the mutations Y20F and L36V, mutant structures were generated with the program WHAT IF (74). The wild-type structure used in the calculations is model 1 of the PDB structure 1E0L (35). To calculate ΔG1 and ΔG2, substructures consisting of the residues 1–24 and 15–37 of the PDB structure have been used. The FOLD-X calculations have been performed at the ionic strength 150 mM and temperature 283 K of the experiments (33). Numbers in brackets indicate that the calculated stability changes are not reliable since ΔGN differs by more than a factor 2 from ΔGN,exp.