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Updated: May 25, 2026
05:54
Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization
Published on: September 8, 2023
Spontaneous inter-conversion of insulin fibril chirality
Dmitry Kurouski1, Rina K Dukor, Xuefang Lu
1Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave., Albany, NY 12222, USA.
Chemical Communications (Cambridge, England)
|January 14, 2012
Summary
A minor pH shift can trigger a change in insulin fibrils, altering their structure and morphology. This study reveals how amyloid fibril polymorphs transform and overturn supramolecular chirality.
Area of Science:
- Biochemistry
- Structural Biology
- Neuroscience
Background:
- Amyloid fibrils are implicated in neurodegenerative diseases.
- These fibrils represent a stable, energetically favorable protein conformation.
Purpose of the Study:
- To investigate the impact of small environmental changes on amyloid fibril structure.
- To explore the transformation dynamics between different fibril polymorphs.
Main Methods:
- Induction of fibril transformation using a controlled pH shift.
- Characterization of morphological and structural changes in insulin fibrils.
Main Results:
- A small pH alteration induced spontaneous transformation of insulin fibrils.
- The transformation resulted in a change from one fibril polymorph to another.
- Supramolecular chirality of the fibrils was overturned, accompanied by morphological and structural shifts.
Conclusions:
- Environmental factors like pH can significantly influence amyloid fibril structure and polymorph.
- Fibril supramolecular chirality is sensitive to and can be reversed by pH-induced transformations.
- Understanding these transformations is crucial for neurodegenerative disease research.
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