Evaluation of the structural stability of amyloid fibrils by dynamic light scattering

Amyloid fibrils, formed by protein mis-folding, consist of consecutive hydrogen bonds situated between β-strands. To date, experimental data indicate that amyloid fibrils are structured according to the cross-β structure model, wherein β-strands are oriented perpendicular to the fibril axes. Amyloid fibrils are generally 10 nm in width; however, barnase M1 variants are 20 nm in width. In this study, we performed a comparative analysis of the structural stability of amyloid formation by barnase M1 variants. Based on the results of dynamic light scattering, we propose that the presence or absence of C-terminal amino acids in barnase M1 is dependent on resistance to urea.