貝它糊蛋白寡聚體被認為與阿茲海默症有很大的關聯。在前人研究中認為可溶性寡聚體毒性比纖維狀寡聚體更具毒性，因此本文中我們以分子動力學研究可溶性貝它糊蛋白球型寡聚體的結構與毒性關係。根據前人研究中認為可溶性球寡聚體會以二聚體為一個單元聚集成更大的寡聚體，且認為二聚體、四聚體、六聚體為中間態，十二聚體為穩定態。因此我們針對二聚體、四聚體、六聚體、十二聚體等四種聚集模型，將其置入水溶液中進行結構模擬與分析。研究結果顯示，二聚體在模擬過程中會有折疊現象，在C端與N端還是能保有大部分的Beta-sheet結構。在各寡聚體比較中發現十二聚體均方根誤差、迴轉半徑、都比中間態的寡聚體振動幅度較小能量也較低，平均氫鍵數較多。因此我們認為相較於其他寡聚體，十二聚體是最穩定且最具神經毒性的寡聚體。

The assembly of amyloid beta (Aβ) protein into oligomers is linked to Alzheimer’s disease. In this study, structure-neurotoxicity relationship of soluble Aβ globulomer was performed using molecular dynamics simulations. According to previos research suggest that souble globular oligomers contains a peptide dimer-repeating unit, and then dimer, tetramer and hexamer were intermediate state, dodecamer was stable state. The solvated Aβ oligomers including dimer, tetramer, hexamer and dodecamer are studied and further analyzed. Our result show that dimer was fold, but it beta-sheet structure were protected in N-terminal and C-terminal. To compare every oligomers find that dodecamer oligomer possesses the most stable structure and further induces strong neurotoxicity.

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