The primary pathological characteristic of Alzheimer's disease is the presence in the brain of self-assembled beta amyloid (Abeta) protein fibrils, consisting of 35-43 amino acid residues. The toxicity of the aggregated protein structures has previously been proposed to be related to the interaction of Abeta fibrils with neuronal membranes (phospholipid bilayers). Here, surfaces consisting of self-assembled alkanethiol monolayers with different end groups--supported on Au--are used to test the effect of surface chemistry on the structure and morphology of aggregates formed from an active fragment (Abeta10-35) of the Abeta peptide. The influence of monolayer nature (end group) on the aggregation of Abeta10-35 was examined using reflection-absorption infrared spectroscopy (RAIRS) and scanning force microscopy (SFM). Evaluation of the SFM and RAIRS data reveals the presence of Abeta10-35 protein on the various monolayer surfaces, with the surface protein possessing predominantly beta-sheet and random-coil conformations. Time-dependent studies of the extent of Abeta10-35 aggregation and deposition on the various surfaces and the effect of the monolayers on seeding of Abeta10-35 aggregates in solution are also discussed.

中文翻译：

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β-淀粉样蛋白肽在金上被共取代的烷硫醇单分子层表面诱导的聚集作用。

阿尔茨海默氏病的主要病理特征是大脑中存在由35-43个氨基酸残基组成的自组装β淀粉样蛋白（Abeta）蛋白原纤维。先前已提出聚集蛋白结构的毒性与Abeta原纤维与神经元膜（磷脂双层）的相互作用有关。在这里，由Au支撑的具有不同端基的自组装烷硫醇单层组成的表面用于测试表面化学对由Abeta活性片段（Abeta10-35）形成的聚集体的结构和形态的影响肽。使用反射吸收红外光谱（RAIRS）和扫描力显微镜（SFM）检查了单层性质（端基）对Abeta10-35聚集的影响。对SFM和RAIRS数据的评估表明，在各种单层表面上都存在Abeta10-35蛋白，该表面蛋白主要具有beta-sheet和无规卷曲构象。还讨论了与时间有关的Abeta10-35聚集和沉积在各种表面上的程度以及单层对溶液中Abeta10-35聚集体播种的影响。