Fig. 5.

Diflunisal increases TTR stability to chemical denaturation. WT (A), Leu55Pro (B), and Glu51_Ser52dup (C) in the absence (Top) or presence (Bottom) of diflunisal were incubated in 0–4 M urea (color-coded light to dark) at 37 °C for up to 92 h, during which intrinsic Trp fluorescence was measured. The ratio of the emission intensity at 355 nm and 335 nm, I₃₅₅/I₃₃₅, versus time depicts the kinetics of protein unfolding. In diflunisal-containing samples, 360 μM diflunisal and a 25:1 drug/protein molar ratio were used.