Figure 2.
(A) Amino acid sequences of single-chain fragments of H-peptide. In ACC and B-7A, Cys residues involved in the interchain disulfide bond were substituted with alanine (marked in red). (B) Comparison of de novo aggregation kinetics of ACC, B-7A, and B-SH versus H-fragment probed by fluorescence of ThT. Samples of H, ACC, and B-SH were dissolved at 2 mg/mL concentration in 50 mM NaCl, 1.33 M GdnHCl, 20 μM ThT, pH 1.9. B-SH sample contained also TCEP at 6.8 mg/mL concentration. B-7A peptide was dissolved at 1 mg/mL concentration in ∼9 vol/vol % DMSO in 50 mM NaCl, 20 μM ThT, pH 1.9. Measurements were carried out at 37 °C and 300 rpm agitation.