Figure 2.

Thermal melting of E1_5 at pH 7.0, followed by CD spectroscopy and DSC. Temperature-induced changes in MRE₂₂₂ are shown in A. Protein concentration was 30 μM. (B) The same data in the derivative mode (symbols). The best fit according to equations 1–3 with T_m = 44.2°C and ΔH_vH,CD = 130 ± 10 kJ mole⁻¹ is visualized by the continuous line. (C) Partial molar heat capacity changes upon heating at 1° min⁻¹. Protein concentration was 150 μM. The experimental data are shown as a continuous line. The broken line is the best fit for a two-state unfolding model determined with T_m = 48°C, ΔH_fit = 136 ± 5 kJ mole⁻¹ and ΔC_p = 2.0 ± 0.2 kJ K⁻¹ mole⁻¹. (D) Superposition of the excess heat capacity obtained by calorimetry (dashed line) and the temperature derivative of MRE₂₂₂ (continuous line) is shown. To facilitate the comparison, both functions were arbitrarily scaled.