Fig. 5.

Oligomer free energies expressed relative to the monomeric state for β-sheet oligomers (a) and amorphous aggregates (b), for STVIYE^(-) (circles) and STVIYE (squares). The free energy curves were calculated from the enthalpies shown in Fig. 3 using a constant entropic cost, TΔS_n^th = −28.5 ± 1.0 kcal/mol. These free energies correspond to a 1 mM concentration of monomeric peptide—the concentration at which STVIYE^(-) and other hexapeptides form fibrils in vitro.¹⁸,²⁶