Figure 3. Contribution of protein domains to self-assembly.

(A) Scattering intensity (measured as the turbidity at 340 nm) of 20 µM Δ21TgCEN1 as a function of time at 37°C in 20 mM Tris–HCl, 20 mM KCl pH 7.5 before (blue line) and upon (black line) addition of 50 µM N21 peptide in the presence of 1 mM CaCl₂. The profile of N21 peptide alone in the presence of 1 mM CaCl₂ is also shown (red line). (B) Particle-size distribution from DLS data of 10 µM Δ21TgCEN1 in 20 mM Tris–HCl, 20 mM KCl pH 7.5 at 37°C before (solid line) and upon (dotted line) addition of 50 µM N21 peptide in the presence of 1 mM CaCl₂. (C and D) Particle-size distribution from DLS data of 10 µM N-TgCEN1 and C-TgCEN1 in 20 mM Tris–HCl pH 7.5 in the presence of 1 mM CaCl₂ at selected KCl concentrations (C) and upon addition of 600 µM ANS (D).