A fibril-like assembly of oligomers of a peptide derived from β-amyloid.

ABSTRACT: A macrocyclic β-sheet peptide containing two nonapeptide segments based on Aβ(15-23) (QKLVFFAED) forms fibril-like assemblies of oligomers in the solid state. The X-ray crystallographic structure of macrocyclic β-sheet peptide 3 was determined at 1.75 Å resolution. The macrocycle forms hydrogen-bonded dimers, which further assemble along the fibril axis in a fashion resembling a herringbone pattern. The extended β-sheet comprising the dimers is laminated against a second layer of dimers through hydrophobic interactions to form a fibril-like assembly that runs the length of the crystal lattice. The second layer is offset by one monomer subunit, so that the fibril-like assembly is composed of partially overlapping dimers, rather than discrete tetramers. In aqueous solution, macrocyclic β-she

SUBMITTER: Pham JD 

PROVIDER: S-EPMC4183627 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature