Dynamics and Fluidity of Amyloid Fibrils:  A Model of Fibrous Protein Aggregates

A previous experimentally defined model for the fibril formed from the core residues of the β-amyloid (Aβ) peptides of Alzheimer's disease, 10YEVHHQKLVFFAEDVGSNKGAIIGLM, Aβ(10−35) using spectroscopic and scattering analyses reports on the average structure, benefiting immensely from the homogeneous assembly of Aβ(10−35). However, the energetic constraints that contribute to fibril dynamics and stability remain poorly understood. Here we perform molecular dynamics simulations to extend the structural assignment by providing evidence for a dynamic average ensemble with transient backbone H-bonds and internal solvation contributing to the inherent stability of amyloid fibrils.