TABLE 3.
Thermal and chemical stabilities of 1AQK VLλ and 1VGE VH variants
Stabilities against thermal and chemical (GdmCl) denaturation of the different 1AQK VLλ and 1VGE VH variants are shown. Midpoints of thermal transitions are shown as Tmelt. Because GdmCl-induced unfolding transitions acquired for 1AQK VLλ were reversible, the data were fitted to a two-state equilibrium unfolding model to obtain the thermodynamic stability of unfolding (ΔGU), as well as the cooperativity parameter (m value), for a qualitative comparison of the data. When due to too less an amount of proteins, the chemical stability experiments could not be performed (NA).
| Variable domain variant | Tmelt | ΔG | M value |
|---|---|---|---|
| °C | kJ mol−1 | kJ mol−1 m−1 | |
| 1AQK VLλ-WT | 44.0 ± 0.2 | −5.7 ± 1.3 | 13.1 ± 1.1 |
| AQ-N2E | 44.9 ± 0.5 | −6.4 ± 1.7 | 15.1 ± 1.9 |
| AQ-N2S | 44.9 ± 0.4 | −11.1 ± 3.0 | 17.8 ± 3.6 |
| 1VGE-VH-WT | 46.5 ± 0.6 | NA | NA |
| VG-V2E | 43.1 ± 0.6 | NA | NA |
| VG-V2A | 43.8 ± 0.5 | NA | NA |