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Rapid Generation of Amyloid from Native Proteins In vitro
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Understanding the Formation of Apoferritin Amyloid Fibrils
Rocío Jurado1, Jozef Adamcik2, Antoni Sánchez-Ferrer2
1Department of Inorganic Chemistry, University of Granada, 18071 Granada, Spain.
Biomacromolecules
|April 6, 2021
Summary
Researchers optimized conditions to create long, rigid apoferritin amyloid fibrils. Protein unfolding and hydrolysis into peptide fragments are essential for forming these amyloid-like structures.
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Apoferritin is a protein shell involved in iron storage.
- Amyloid fibrils are associated with various diseases and are studied for their unique structures.
- Understanding protein fibrillation pathways is crucial for both understanding disease mechanisms and developing novel biomaterials.
Purpose of the Study:
- To optimize experimental conditions for producing long, rigid apoferritin protein amyloid fibrils.
- To elucidate the fibrillation pathway of apoferritin.
- To investigate the role of protein unfolding and hydrolysis in fibril formation.
Main Methods:
- Atomic Force Microscopy (AFM) for morphology and fibril growth.
- Transmission Electron Microscopy (TEM) for ultrastructural analysis.
- Dynamic Light Scattering (DLS), Circular Dichroism (CD), Fourier-Transform Infrared Spectroscopy (FTIR), and Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) for biochemical and structural characterization.
Main Results:
- Optimized conditions yielded small aggregates, medium, and long apoferritin fibrils.
- Extended incubation led to protein unfolding and hydrolysis into short peptide fragments.
- AFM, SDS-PAGE, and CD data supported a common fibrillation mechanism involving hydrolyzed fragments.
Conclusions:
- Protein unfolding and hydrolysis are essential for the formation of apoferritin amyloid-like fibrils.
- A universal fibrillation mechanism involving peptide fragments was identified.
- The study provides insights into the structural transformation of apoferritin into amyloid structures.
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