Figure 7.

Temperature evolution of ¹H^N and ¹⁵N chemical shifts of the denatured ensemble. (a) The glycine-rich region of the HSQC spectrum of the denatured ensembles of human lysozyme variants. In each case the top spectrum, in red, corresponds to a temperature of 50 °C; spectra were recorded every 2.5 °C and are all shown with the same contour levels as in Figure 5. (b) Temperature coefficients of ¹H^N amide chemical shifts of glycine residues of the denatured ensemble. The temperature coefficients are determined as the slope of a linear fit of chemical shifts versus temperature. Results are shown for the WT (black), the I59T (red), and the I56T (green) variants. (c) Plot of residuals of ¹H^N and ¹⁵N chemical shifts, after subtraction of the best first-order fit. The P-value shown in the inset of each graph relates to the comparison of fits to first- and second-order polynomial functions. Only residues for which one chemical shift (¹H^N or ¹⁵N) has P < 0.05 are shown.