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Updated: Aug 26, 2025
08:53
Characterization of pH-Dependent Reversible Self-Assembly of Amyloid Beta 1-40-Coated Gold Colloids
Published on: March 21, 2025
847
Nonequilibrium Amyloid Polymers Exploit Dynamic Covalent Linkage to Temporally Control Charge-Selective Catalysis
Surashree Goswami1, Antara Reja1, Sumit Pal1
1Department of Chemical Sciences and Centre for Advanced Functional Materials, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, West Bengal, India.
Journal of the American Chemical Society
|October 11, 2022
Summary
A novel amyloid peptide forms dynamic microphases with coenzymes, enabling tunable catalysis. This self-assembly and disassembly process mimics natural enzymes by controlling surface charge over time.
Area of Science:
- Biochemistry
- Materials Science
- Chemical Biology
Background:
- Proteins utilize charged coenzymes for biological functions.
- Amyloid peptides can self-assemble into functional structures.
Purpose of the Study:
- To investigate amyloid peptide-coenzyme interactions.
- To explore the dynamic catalytic properties of amyloid microphases.
Main Methods:
- Amyloid peptide synthesis and characterization.
- Coenzyme binding and polymerization studies.
- Surface charge analysis and catalytic activity assays.
Main Results:
- Amyloid peptide reversibly binds coenzymes via covalent linkage, forming amyloid microphases.
- Hydrolysis of coenzymes triggers depolymerization and alters assembly surface charge.
- Dynamic surface charge modulation leads to time-dependent catalytic activity.
Conclusions:
- Amyloid microphases can serve as artificial enzymes.
- Reversible polymerization and dynamic charge control are key to tunable biocatalysis.
- This system offers insights into the evolution of protein catalysis.
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