Figure 1. Persistence of fingerprint infrared features (amide I’ band region) characteristic for [BI] amyloid upon repeated passages of homologous seeding.

Mother [BI] amyloid (marked as 0^th generation) was obtained through spontaneous quiescent aggregation of 1 wt. % BI in 0.1 M NaCl in D₂O, pD 1.9 at 65 °C. Subsequently, amyloid fibrils of nth-generation were used to induce (n + 1)th generation of fibrils (indicated on the right side) through 96 h-long quiescent incubation at 37 °C of 1 wt % native BI in 0.1 M NaCl, D₂O, pD 1.9 in the presence of preformed sonicated seeds (1:100 mass ratio of amyloid: native BI). Samples of grown daughter fibrils were sonicated prior to FT-IR measurements in order to sharpen spectral features.