title: A new structural model of Aβ40 fibrils.
abstract: The amyloid fibrils of beta-amyloid (Aβ) peptides play important roles in the pathology of Alzheimer's disease. Comprehensive solid-state NMR (SSNMR) structural studies on uniformly isotope-labeled Aβ assemblies have been hampered for a long time by sample heterogeneity and low spectral resolution. In this work, SSNMR studies on well-ordered fibril samples of Aβ(40) with an additional N-terminal methionine provide high-resolution spectra which lead to an accurate structural model. The fibrils studied here carry distinct structural features compared to previous reports. The inter-β-strand contacts within the U-shaped β-strand-turn-β-strand motif are shifted, the N-terminal region adopts a β-conformation, and new inter-monomer contacts occur at the protofilament interface. The revealed structural diversity in Aβ fibrils points to a complex picture of Aβ fibrillation.
authors: Magnetic Resonance Center (CERM), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy. ivanobertini@cerm.unifi.it
authors: Ivano
authors: I
authors: Bertini
authors: Leonardo
authors: L
authors: Gonnelli
authors: Claudio
authors: C
authors: Luchinat
authors: Jiafei
authors: J
authors: Mao
authors: Antonella
authors: A
authors: Nesi
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism; D000682:Amyloid / Q000737:chemistry* / Q000648:ultrastructure; D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000648:ultrastructure; D006801:Humans; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry* / Q000648:ultrastructure; D017433:Protein Structure, Secondary
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40)