Table I.
Unfolding free energies of FKBP12 and 14 FKBP12.6-based variants
| Variant | ΔGu (kcal/mol)a | ΔΔGu (kcal/mol)b |
|---|---|---|
| Wild-type FKBP12 | 5.07 ± 0.02 | |
| Wild-type FKBP12.6 | 3.85c | −1.22 |
| Q3E | 4.73 ± 0.10 | −0.34 |
| R18K | 5.27 ± 0.13 | 0.20 |
| E31Q | 5.10 ± 0.13 | 0.03 |
| D32N | 5.15 ± 0.13 | 0.08 |
| E31Q/D32N | 5.53 ± 0.10 | 0.46 |
| D37S | 4.63 ± 0.10 | −0.44 |
| R42A | 4.43 ± 0.10 | −0.64 |
| D37S/R42A | 4.89 ± 0.01 | −0.18 |
| M49R | 5.21 ± 0.20 | 0.14 |
| R57K | 4.77c | −0.30 |
| H94N | 5.73 ± 0.10 | 0.66 |
| K105N | 5.21 ± 0.10 | 0.14 |
| E31Q/D32N/H94N | 5.94 ± 0.18 | 0.87 |
aData are reported as mean plus/minus standard error of measurement.
bChange in unfolding free energy relative to wild-type FKBP12.
cData from a single measurement. Since these were destabilizing variants, more precise determination of ΔGu was not pursued.