Aggregating the amyloid Aβ11-25 peptide into a four-stranded β-sheet structure (original) (raw)

We present a detailed analysis of the structural properties of one monomer of Ab 11-25 as well as of the aggregation mechanisms for four chains of Ab 11-25 using the activation-relaxation technique coupled with a generic energy potential. Starting from a random distribution of these four chains, we find that the system assembles rapidly into a random globular state that evolves into threeand four-stranded antiparallel b-sheets. The aggregation process is considerably accelerated by the presence of preformed dimers. We also find that the reptation mechanism already identified in shorter peptides plays a significant role here in allowing the structure to reorganize without having to fully dissociate. Proteins 2006;65:877-888. V V C 2006 Wiley-Liss, Inc.