Suvorina Mariya Yu, Selivanova Olga M, Grigorashvili Elizaveta I, Nikulin Alexey D, Marchenkov Victor V, Surin Alexey K, Galzitskaya Oxana V
Institute of Protein Research, Russian Academy of Science, Pushchino, Moscow Region, Russia.
State Research Center for Applied Microbiology & Biotechnology, Obolensk, Serpukhov District, Moscow Region, Russia.
J Alzheimers Dis. 2015;47(3):583-93. doi: 10.3233/JAD-150147.
The aim of this study was to investigate the process of amyloidogenesis of amyloid-β (Aβ)42 peptide, by means of fluorescence spectroscopy, electron microscopy, X-ray diffraction, and mass spectrometry. It has been repeatedly reported in the literature that the process of fibril formation by Aβ42 peptide depends considerably not only upon the specific conditions (ionic conditions, pH, temperature, mixing, etc.), as well as the manufacturing route (synthetic or recombinant), but also on the methods of synthesis and purification. We have, for the first time, systematically analyzed samples of Aβ42 peptide supplied by five different companies (Anaspec, Invitrogen, Enzo, Sigma-Aldrich, and SynthAssist) and obtained evidence of significant variability, including lot to lot variations. All studied samples formed amyloid-like fibrils at pH3-6, and the fibrils contained cross-β structures. Samples from Anaspec, Invitrogen, and Enzo formed one particular type of amyloid-like fibrils, while the samples from Sigma-Aldrich and SynthAssist formed another distinct type of fibrils. The observed polymorphism emphasizes the capacity of the Aβ42 peptide to act as a prion agent with varying structural characteristics. The presented data have allowed us to propose a possible mechanism of formation of amyloid-like fibrils.
本研究的目的是通过荧光光谱法、电子显微镜、X射线衍射和质谱法，研究β淀粉样蛋白（Aβ）42肽的淀粉样蛋白生成过程。文献中多次报道，Aβ42肽形成原纤维的过程不仅在很大程度上取决于特定条件（离子条件、pH值、温度、混合等）以及制造途径（合成或重组），还取决于合成和纯化方法。我们首次系统分析了由五家不同公司（Anaspec、Invitrogen、Enzo、Sigma-Aldrich和SynthAssist）提供的Aβ42肽样品，并获得了显著变异性的证据，包括批次间的差异。所有研究样品在pH3 - 6时均形成淀粉样原纤维，且这些原纤维含有交叉β结构。来自Anaspec、Invitrogen和Enzo的样品形成了一种特定类型的淀粉样原纤维，而来自Sigma-Aldrich和SynthAssist的样品则形成了另一种不同类型的原纤维。观察到的多态性强调了Aβ42肽作为具有不同结构特征的朊病毒样因子的能力。所呈现的数据使我们能够提出一种可能的淀粉样原纤维形成机制。
