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Updated: Aug 9, 2026
09:06
Amyloid and the Cross-Beta Architecture
Published on: February 13, 2026
Interaction-based evaluation of the propensity for amyloid formation with cross-beta structure
Masatoshi Saiki1, Takeo Konakahara, Hisayuki Morii
1National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 6, Tsukuba, Ibaraki 305-8566, Japan.
Biochemical and Biophysical Research Communications
|April 4, 2006
Summary
A new prediction method identifies amino acid sequences prone to forming amyloid fibrils. This method accurately predicts amyloid structures based on specific interaction conditions, aiding in understanding amyloidogenicity.
Area of Science:
- Biochemistry
- Structural Biology
- Computational Biology
Background:
- Amyloid fibrils are associated with various diseases.
- Understanding the sequence requirements for amyloid formation is crucial for disease research.
Purpose of the Study:
- To develop a novel prediction method for identifying amino acid sequences prone to forming amyloid fibrils.
- To validate a structural model for amyloidogenicity based on specific residue interactions.
Main Methods:
- Developed a prediction system based on a structural model of amyloids.
- Introduced two conditions: antiparallel beta-strand interactions along a fibril axis and line-matching hydrophobic interactions on protofibril faces.
- Evaluated peptide sequences using the developed scoring system.
Main Results:
- Peptides with high scores readily formed amyloid fibrils when combined with a turn-inducing structure.
- Low-scoring native sequences and modified sequences (null score) did not form amyloids.
- Predicted high-scoring regions aligned with known putative amyloid core regions.
Conclusions:
- The developed method accurately predicts amyloid structures and sequence propensity.
- The study supports the proposed structural model for amyloid formation.
- This predictive tool aids in understanding the molecular basis of amyloid diseases.
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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...
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