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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Chirality of amyloid suprastructures.
Noa Rubin1, Emanuel Perugia, Michal Goldschmidt
1Department of Structural Biology, Weizmann Institute of Science, Rehovot, Israel 76100.
Journal of the American Chemical Society
|March 15, 2008
Summary
Amyloid fibrils exhibit distinct helical structures. Researchers found that while most amyloids form left-handed helices, serum amyloid A peptides create right-handed ones, revealing structural organization influences chirality.
Area of Science:
- Biochemistry
- Structural Biology
- Biophysics
Background:
- Amyloids are protein aggregates linked to over 20 diseases.
- Amyloid fibers possess a characteristic cross-beta structure forming helical suprastructures.
Purpose of the Study:
- To investigate the chirality of amyloid suprastructures using high-resolution microscopy.
- To determine if molecular chirality dictates supramolecular helical organization in amyloids.
Main Methods:
- High-resolution Scanning Electron Microscopy (SEM).
- Cryo-Scanning Electron Microscopy (Cryo-SEM).
Main Results:
- Amyloids of Abeta1-40 and hen lysozyme exclusively form left-handed helices.
- Serum amyloid A (SAA1-12) peptides form exclusively right-handed helices.
- Peptide enantiomers ((R)-amino acids) aggregate into left-handed helices.
Conclusions:
- The right-handedness of SAA1-12 amyloids is an intrinsic peptide feature.
- Left-handed helices align with the conventional beta-sheet model.
- Right-handed SAA1-12 helices suggest its cross-beta structure may not involve beta-sheets, highlighting structural organization's role in supramolecular chirality.
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