Figure 6.

M-TTR undergoes a specific conformational change, while maintaining the topology, upon binding to Aβ₄₂ ADDLs. (a–c) Far-UV CD spectra of M-TTR (a), Aβ₄₂ ADDLs (b), and M-TTR plus Aβ₄₂ ADDLs (c) measured at the indicated times of incubation using a protein concentration of 0.1 mg mL^–1 (a, b) or 0.2 mg mL^–1 with a 1:1 mass ratio of M-TTR: Aβ₄₂ ADDLs (c). In panel (c), the experimental spectra (continuous lines) are compared with those obtained by summing the spectra of M-TTR alone and ADDLs alone (dashed lines). (d–h) Fluorescence spectra recorded for both M-TTR (d, e) and DACM-M-TTR (g, h) in the absence (d, g) and presence (e, h) of Aβ₄₂ ADDLs after the indicated times of incubation. Fluorescence spectra recorded for Aβ₄₂ ADDLs alone are also shown (f). (i) FRET E values of M-TTR in the absence (green) and presence (red) of Aβ₄₂ ADDLs.