Department of Biochemistry and Molecular Pharmacology, Instituto di Ricerche Farmacologiche "Mario Negri", 20156 Milano, Italy.
Anal Biochem. 2011 Apr 15;411(2):297-9. doi: 10.1016/j.ab.2010.12.032. Epub 2010 Dec 24.
Preparing reliable, seed-free stock solutions of the highly amyloidogenic peptides amyloid-β (Aβ) is difficult. Besides the formation of aggregates during synthesis and storage, dissolution of the peptide is a critical step because vortexing can induce aggregation. To overcome this, synthesis of the more water-soluble depsi-Aβ(1-42) peptide, from which the native sequence is easily obtained, has been suggested. We further refined this technique, including a cutoff filtration step and switching the depsipeptide in basic conditions, to stabilize the formed native peptide. The obtained solutions of native Aβ(1-40) and Aβ(1-42) peptides were homogeneous and aggregate free, as indicated by thioflavin T and circular dichroism analysis.
制备高淀粉样蛋白的肽淀粉样β（Aβ）可靠、无种子的储备溶液是困难的。除了在合成和储存过程中形成聚集体之外，肽的溶解也是一个关键步骤，因为涡旋会诱导聚集。为了克服这个问题，建议合成更水溶性的 depsi-Aβ（1-42）肽，从该肽很容易获得天然序列。我们进一步改进了这项技术，包括过滤步骤和在碱性条件下切换 depsi 肽，以稳定形成的天然肽。通过硫黄素 T 和圆二色性分析表明，所获得的天然 Aβ（1-40）和 Aβ（1-42）肽溶液是均相的，没有聚集体。
