4.6 Article

Aggregation Pathways of the Amyloid β(1-42) Peptide Depend on Its Colloidal Stability and Ordered β-Sheet Stacking

期刊

LANGMUIR
卷 28, 期 35, 页码 12711-12721

出版社

AMER CHEMICAL SOC
DOI: 10.1021/la3021436

关键词

-

资金

  1. NINDS [SC1MS0701555-01]
  2. NSF [1112105]
  3. ACS-Petroleum Research Funds [49390-UR10]
  4. NSF-CREST [JRD-0932421]
  5. NIH-NCMHD [P20 MD001089-03]
  6. Direct For Mathematical & Physical Scien
  7. Division Of Chemistry [1112105] Funding Source: National Science Foundation
  8. Division Of Human Resource Development
  9. Direct For Education and Human Resources [0932421] Funding Source: National Science Foundation

向作者/读者索取更多资源

Amyloid beta (A beta) fibrils are present as a major component in senile plaques, the hallmark of Alzheimer's disease (AD). Diffuse plaques (nonfibrous, loosely packed A beta aggregates) containing amorphous A beta aggregates are also formed in brain. This work examines the influence of Cu2+ complexation by A beta on the aggregation process in the context of charge and structural variations. Changes in the surface charges of A beta molecules due to Cu2+ binding, measured with a zeta-potential measurement device, were correlated with the aggregate morphologies examined by atomic force microscopy. As a result of the charge variation, the colloid-like stability of the aggregation intermediates, which is essential to the fibrillation process, is affected. Consequently, Cu2+ enhances the amorphous aggregate formation. By monitoring variations in the secondary structures with circular dichroism spectroscopy, a direct transformation from the unstructured conformation to the beta-sheet structure was observed for all types of aggregates observed (oligomers, fibrils, and/or amorphous aggregates). Compared to the A beta aggregation pathway in the absence of Cu2+ and taking other factors affecting A beta aggregation (i.e., pH and temperature) into account, our investigation indicates that formations of amorphous and fibrous aggregates diverge from the same beta-sheet-containing partially folded intermediate. This study suggests that the hydrophilic domain of A beta also plays a role in the A beta aggregation process. A kinetic model was proposed to account for the effects of the Cu2+ binding on these two aggregation pathways in terms of charge and structural variations.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.6
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据