Related Experiment Video
Updated: Jun 16, 2026
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Amyloid-beta42 oligomer structures from fibrils: a systematic molecular dynamics study.
Anselm H C Horn1, Heinrich Sticht
1Bioinformatik, Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
The Journal of Physical Chemistry. B
|January 29, 2010
Summary
Small amyloid-beta42 oligomers are key in Alzheimer's disease. Simulations show larger oligomers (trimer-pentamer) are stable, while dimers change shape, suggesting multiple drug targets for Alzheimer's disease treatment.
Area of Science:
- Neuroscience
- Biochemistry
- Computational Biology
Background:
- Soluble amyloid-beta42 (Aβ42) oligomers are implicated in Alzheimer's disease pathogenesis.
- These oligomers possess neurotoxic properties and can initiate fibril formation.
Purpose of the Study:
- To investigate the structural stability and conformational dynamics of Aβ42 oligomers (monomer to pentamer).
- To understand the relationship between oligomer structure and their role in Alzheimer's disease progression and fibril seeding.
Main Methods:
- All-atom molecular dynamics simulations in explicit solvent.
- Simulations were performed on five Aβ42 oligomers, from monomer to pentamer, initiated from fibril conformations.
- Total simulation time of 0.7 microseconds.
Main Results:
- Aβ42 trimers to pentamers remained stable, preserving key beta-sheet structures similar to fibrils.
- Aβ42 dimers exhibited significant C-terminal conformational changes, forming an antiparallel beta-sheet to shield hydrophobic residues.
- Larger oligomers were stabilized by interchain salt bridges (D23-K28), while dimers showed a D23-N27 interaction.
Conclusions:
- The structural similarity of trimers and tetramers to fibrils explains their potent seeding activity.
- The distinct conformations of dimers suggest they may represent a separate therapeutic target.
- Targeting structurally diverse Aβ42 oligomers may be necessary for effective Alzheimer's disease drug design.
Related Concept Videos
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
01:22Protein Folding
Overview
02:15Protein and Protein Structure
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...