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Updated: Jul 10, 2026

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Biochemical Purification and Proteomic Characterization of Amyloid Fibril Cores from the Brain
Published on: April 28, 2022
Linking folding with aggregation in Alzheimer's beta-amyloid peptides
Jana Khandogin1, Charles L Brooks
1Department of Molecular Biology,Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Summary
Alzheimer's beta-amyloid (Abeta) peptides aggregate more readily in acidic endosomal environments. This suggests Abeta oligomers may form inside cells before contributing to disease pathology.
Area of Science:
- Neuroscience
- Biochemistry
- Computational Biology
Background:
- Alzheimer's disease (AD) is linked to beta-amyloid (Abeta) peptides.
- Abeta peptides are generated in early endosomes.
- Small Abeta oligomers are considered the primary toxic species in AD.
Purpose of the Study:
- Investigate the effect of pH on Abeta conformational changes.
- Determine how endosomal acidity influences Abeta aggregation.
Main Methods:
- Constant pH molecular dynamics simulations.
- Studied two model peptides: Abeta(1-28) and Abeta(10-42).
Main Results:
- Solution pH significantly modulates the Abeta folding landscape.
- Hydrophobically driven Abeta aggregation is most favorable at pH 6.
- Endosomal pH conditions promote Abeta conformational changes conducive to aggregation.
Conclusions:
- Abeta oligomers may form intracellularly within endosomes.
- Intracellular Abeta oligomers could precede extracellular plaque formation.
- Early intracellular aggregation may contribute to AD pathogenesis.
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