Table 1.
Thermodynamic parameters of mutant PrPs
| Core mutation | ΔG, kJ mol−1 | ΔΔG, kJ mol−1 | m, kJ mol−1 M−1 | Midpoint molar activity |
|---|---|---|---|---|
| WT | −30.99 ± 0.85 | −6.32 ± 0.16 | 2.00 ± 0.01 | |
| F175A | −28.51 ± 0.70 | 2.48 ± 1.10 | −6.12 ± 0.16 | 1.91 ± 0.09 |
| V180A | −26.10 ± 0.93 | 4.89 ± 1.26 | −6.70 ± 0.27 | 1.59 ± 0.01 |
| I184V | −30.12 ± 0.46 | 0.87 ± 0.97 | −6.58 ± 0.09 | 1.87 ± 0.003 |
| M205A | −18.06 ± 0.80 | 12.92 ± 1.17 | −4.43 ± 0.19 | 1.67 ± 0.01 |
| M206A | −24.72 ± 1.12 | 6.27 ± 1.41 | −6.33 ± 0.24 | 1.59 ± 0.01 |
| V209A | −29.74 ± 0.53 | 1.25 ± 1.01 | −6.02 ± 0.10 | 2.02 ± 0.004 |
| M213A | −17.94 ± 0.70 | 13.05 ± 1.11 | −5.13 ± 0.23 | 1.43 ± 0.02 |
The free energy change (ΔG), degree of destabilization (ΔΔG), cooperativity (m) and midpoint (Tm) of the equilibrium unfolding transition for each protein were calculated by using a 2-state model of folding. Unfolding was induced by GuHCl and monitored by CD at 222 nm, at 21.5 °C and pH 8.0. The folding midpoint is expressed as molar denaturant activity, derived from GuHCl concentration as described in SI Text.