University of Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 351 cours de la Libération, 33405, Talence cedex, France.
University of Bordeaux, Institut de Chimie et Biologie des Membranes et des Nano-objets, CNRS UMR 5248, Allée Geoffroy Saint Hilaire, 33600, Pessac, France.
Angew Chem Int Ed Engl. 2017 Feb 6;56(7):1771-1774. doi: 10.1002/anie.201610399. Epub 2017 Jan 10.
For the first time, natural Aβ fibrils (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.
首次使用尖端增强拉曼光谱（TERS）对涉及阿尔茨海默病的天然 Aβ 纤维（WT）以及两种形成毒性较低的淀粉样纤维（L34T）和毒性较高的寡聚物（oG37C）的两种合成突变体进行了化学表征。尽管与三种肽相关的 TERS 特征的比例相似，但仔细检查酰胺 I 和酰胺 III 带允许我们清楚地区分 WT 和 L34T 纤维组织成平行β-折叠，而较小且毒性较高的 oG37C 寡聚物则组织成反平行β-折叠。
