Characterization of the Structural Ensembles of Aβ Monomers using a Combined MD/NMR Approach

Abstract

Amyloid ß (Aß) peptides are a primary component of fibrils and oligomers implicated in the etiology of Alzheimer's disease. However, the intrinsic flexibility of these peptides has frustrated efforts to investigate the secondary and tertiary structure of Aß monomers, whose conformational landscapes directly contribute to the kinetics and thermodynamics of Aß aggregation. In this work, de novo replica exchange molecular dynamics (REMD) simulations on the μs/replica timescale are used to characterize the structural ensembles of Aß42, Aß40, and M35-oxidized Aß42, three physiologically prevalent isoforms with substantially different aggregation properties.