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Characterization of pH-Dependent Reversible Self-Assembly of Amyloid Beta 1-40-Coated Gold Colloids
Published on: March 21, 2025
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Chemical catalysis by biological amyloids
1Department of Life Sciences, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
Biochemical Society Transactions
|September 25, 2023
Summary
Natural amyloids, including those linked to diseases like Alzheimer's, can surprisingly catalyze chemical reactions. This newly discovered catalytic activity in amyloid fibers may offer insights into disease mechanisms and potential therapeutic strategies.
Area of Science:
- Biochemistry
- Molecular Biology
- Neuroscience
Background:
- Protein and peptide aggregation into amyloid fibers underlies numerous human diseases.
- Amyloids, characterized by a cross-β fold, are implicated in both pathology and biological functions.
- Traditionally viewed as chemically inert, recent findings challenge this perception.
Purpose of the Study:
- To explore the catalytic potential of natural amyloid structures.
- To investigate the connection between amyloid catalytic activity and metabolic changes in amyloid-related diseases.
- To highlight catalytic activity as a potential gain-of-function in disease-associated amyloids.
Main Methods:
- In vitro studies using model substrates.
- Analysis of amyloid-β, α-synuclein, and glucagon amyloid systems.
- Comparison of catalytic activity with enzymes and synthetic catalytic amyloids.
Main Results:
- Amyloid-β, α-synuclein, and glucagon amyloids demonstrated catalytic activity on biologically relevant reactions.
- The observed catalytic efficiency was lower than enzymes but comparable to designed catalytic amyloids.
- This suggests catalytic activity is an intrinsic property of natural amyloids.
Conclusions:
- Natural amyloids possess previously unrecognized catalytic functions.
- This catalytic activity may be linked to metabolic alterations in amyloid diseases.
- All biological amyloids might harbor undiscovered catalytic capabilities influenced by their specific structures.
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