(A) Turbidity curves showing self-assembly (7 mg/mL, PBS, pH = 7) of a set of triple-helical peptides with a type IV sequence, differing only in their terminal residues: (1) T4α5–491Y at T = 40°C, (2) T4α5–491Y′ at T = 44°C, (3) T4α5–491 at T = 40°C. Inset is the turbidity curve for the peptide T4α5–491, showing the slower kinetics of self-assembly with a timescale of hours. (B) Turbidity curves showing the temperature dependence of self-assembly for peptide T4α5–491Y (7 mg/mL, PBS, pH = 7). (C) DSC profiles of thermal unfolding of peptide T4α5–491Y′ showing two distinct transitions.