FIGURE 5.
Little prevalent Aβ peptides strongly affect the behavior of predominant Aβ. ThT fluorescence was recorded in situ every 5 min at 25 °C with 50 μm Aβ and 12 μm ThT. Values represent the means of two experiments. A and C, irrespective of its concentration, Aβ1–43 (dotted gray line) reduced the lag phase for aggregation (C1) of Aβ1–40 (continuous gray line) without affecting elongation rates (C2). Aβ1–40·Aβ1–43 mixtures displayed higher fluorescence intensity after 8 h incubation (C3) than Aβ1–40 and Aβ1–43 alone. Grayscale code is as in A. B and D, titration of Aβ1–42 (dotted black line) with Aβ1–38 (continuous black line) reduced lag phase (D1) and elongation rate (D2) but increased fluorescence intensity at plateau (D3). Grayscale code is as in Fig. B. A.U., absorbance units.