title: Tip-Enhanced Raman Spectroscopy to Distinguish Toxic Oligomers from Aβ1-42Fibrils at the Nanometer Scale.
abstract: For the first time, natural Aβ1-42fibrils (WT) implicated in Alzheimer's disease, as well as two synthetic mutants forming less toxic amyloid fibrils (L34T) and highly toxic oligomers (oG37C), are chemically characterized at the scale of a single structure using tip-enhanced Raman spectroscopy (TERS). While the proportion of TERS features associated with amino acid residues is similar for the three peptides, a careful examination of amide I and amide III bands allows us to clearly distinguish WT and L34T fibers organized in parallel β-sheets from the small and more toxic oG37C oligomers organized in anti-parallel β-sheets.
authors.affiliation: University of Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 351 cours de la Libération, 33405, Talence cedex, France.
authors.forename: Sébastien
authors.identifier: 0000-0002-9213-7201
authors.initials: S
authors.lastname: Bonhommeau
authors.affiliation: University of Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 351 cours de la Libération, 33405, Talence cedex, France.
authors.forename: David
authors.initials: D
authors.lastname: Talaga
authors.affiliation: University of Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 351 cours de la Libération, 33405, Talence cedex, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Hunel
authors.affiliation: University of Bordeaux, Institut de Chimie et Biologie des Membranes et des Nano-objets, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac, France.
authors.forename: Christophe
authors.identifier: 0000-0003-4110-4677
authors.initials: C
authors.lastname: Cullin
authors.affiliation: University of Bordeaux, Institut de Chimie et Biologie des Membranes et des Nano-objets, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Lecomte
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics; D000682:Amyloid / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods; D009154:Mutation; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics / Q000648:ultrastructure; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D000682:Amyloid; D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)
keywords: amide bands; amyloid fibrils; oligomers; tip-enhanced Raman spectroscopy; toxicity