Creating an Amyloid 'Kaleidoscope' Using Short Iodinated Peptides

Area of Science:

• Biomaterials Science
• Structural Biology
• Nanotechnology

Background:

• Peptide fibrils, including amyloid structures, offer diverse morphologies and properties for bionanomaterial applications.
• A lack of atomic-level understanding hinders the design of peptide fibrils with predictable structures and functions.

Purpose of the Study:

• To elucidate the atomic-level structural basis of peptide fibril assembly and diversity.
• To investigate how chemical modifications, specifically iodination, impact fibril structure and thermostability.
• To design novel peptide fibrils with enhanced properties based on structural insights.

Main Methods:

• Cryogenic electron microscopy (cryo-EM) was employed to determine high-resolution structures.
• Chemical modifications, including site-specific iodination, were introduced to peptide sequences.
• Structure-property relationships were analyzed to understand the impact of modifications on fibril assembly and stability.

Main Results:

• The structural basis for the reversible assembly of the hnRAC1 peptide fibril was revealed.
• Site-specific iodination induced diverse halogen bonding patterns, leading to distinct fibril structures.
• Designed iodinated peptides self-assembled into novel fibril structures with significantly improved thermostability.

Conclusions:

• Atomic-level structural insights enable precise control over peptide fibril assembly and properties.
• Iodination serves as a powerful tool for modulating fibril morphology and enhancing stability.
• This work establishes a framework for designing tunable amyloid nanostructures for advanced bionanomaterial applications.