Table 2.
Thermodynamic parameters for the thermal denaturation of intact and cleaved forms of bovine pancreatic trypsin inhibitor variants at 25°C and pH 4.3
| Protein | ΔGden (kcal/mole) | Δ(ΔGden)a (kcal/mole) | ΔTdenb (°C) | ΔGop,N (kcal/mole) | Kop,Nc |
| Leu6→Met | 12.4 | 8.8 | 37.6 | 6.1 | 3.2 • 10−5 |
| Met6-Glu* | 3.6 | ||||
| Thr11→Met | 13.1 | 8.7 | 10.8 | 6.0 | 3.8 • 10−5 |
| Met11-Gly* | 4.4 | ||||
| Lys15-Alad | 0.2 | 0.72 | |||
| Phe22→Met | 8.8 | 7.2 | 29.3 | 4.5 | 4.9 • 10−4 |
| Met22-Tyr* | 1.6 | ||||
| Leu29→Met | 13.3 | 8.5 | 39.4 | 5.8 | 5.4 • 10−5 |
| Met29-Cys* | 4.8 | ||||
| Thr32→Met | 9.3 | 6.3 | 24.4 | 3.6 | 2.2 • 10−3 |
| Met32-Phe* | 3.0 | ||||
| Arg39→Met | 12.4 | 5.7 | 17.0 | 3.0 | 6.2 • 10−3 |
| Met39-Ala* | 6.7 | ||||
| Lys46→Met | 13.8 | 12.7 | 60.3 | 10.0 | 4.4 • 10−8 |
| Met46-Ser* | 1.1e | ||||
| Glu49→Met | 12.6 | 11.4 | 56.4 | 8.7 | 5.6 • 10−7 |
| Met49-Asp* | 1.2e | ||||
| Met52-Argd | 7.3 | 4.2 • 10−6 | |||
| Arg53→Met | 12.8 | 12.4 | 68 | 9.7 | 7.2 • 10−8 |
| Met53-Thr* | 0.4e | ||||
| Thr54→Met | 12.0 | 8.1 | 36.7 | 5.4 | 1.1 • 10−4 |
| Met54-Cys* | 3.9 |
a Δ(ΔGden) = ΔGden − ΔG*den, changes in the free energy of denaturation on single peptide bond cleavage.
b ΔTden = ΔTden − ΔTden*, changes in denaturation temperature on single peptide bond cleavage.
cKop,N = e− ΔGop,N/RT.
d From Krokoszynska and Otlewski (1996).
e The value was calculated directly from the denaturation curve.