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Related Experiment Video

Updated: Jun 27, 2025

Rapid Generation of Amyloid from Native Proteins In vitro

Rapid Generation of Amyloid from Native Proteins In vitro

Published on: December 5, 2013

Catalysis driven by an amyloid-substrate complex.

Taka Sawazaki¹, Daisuke Sasaki¹, Youhei Sohma¹

¹Department of Medicinal Chemistry, School of Pharmaceutical Sciences, Wakayama Medical University, Wakayama 640-8156, Japan.

Proceedings of the National Academy of Sciences of the United States of America

|May 1, 2024

Summary

This summary is machine-generated.

A novel amyloid catalyst system (CASL) activates ammonium ions for amine modification reactions under acidic conditions. This breakthrough enables common chemical transformations previously hindered by low pH.

Keywords:

amyloid amyloid catalyst catalysis nucleophilic reaction

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Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain

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Published on: August 28, 2012

Area of Science:

Chemical Biology
Organic Chemistry
Biocatalysis

Background:

Amine modification is crucial in chemistry and biology.
Alkyl amines are poorly nucleophilic in acidic buffers due to ammonium ion formation.
Existing methods struggle with amine modification under acidic, biorelevant conditions.

Purpose of the Study:

To develop a novel catalytic system for amine modification in acidic buffer.
To overcome the limitations of ammonium ion nucleophilicity at acidic pH.
To demonstrate the versatility of amyloid catalysts in promoting amine transformations.

Main Methods:

Development of a catalysis driven by amyloid-substrate complex (CASL) system.
Utilizing a specific amyloid catalyst (NL6) derived from islet amyloid polypeptide (IAPP).
Employing crystallographic analysis and chemical modification studies to elucidate the catalytic mechanism.

Main Results:

CASL effectively promotes various amine modifications (acylation, arylation, cyclization, alkylation) in acidic buffer.
The carbonyl oxygen of the Phe-Gly amide bond in NL6 is key for activating substrate amines via hydrogen bonding.
Selective conversion of substrates with similar amine reactivity was achieved using amyloid catalysts.
Demonstrated the utility of CASL for amine modifications under acidic conditions.

Conclusions:

CASL represents a unique molecular transformation system for amine modification.
Amyloid catalysts can activate ammonium ions, enabling reactions previously difficult at acidic pH.
This method offers a new approach for amine functionalization in chemistry and biology.