Designed peptides that assemble into cross-α amyloid-like structures.

ABSTRACT: Amyloids adopt 'cross-β' structures composed of long, twisted fibrils with β-strands running perpendicular to the fibril axis. Recently, a toxic peptide was proposed to form amyloid-like cross-α structures in solution, with a planar bilayer-like assembly observed in the crystal structure. Here we crystallographically characterize designed peptides that assemble into spiraling cross-α amyloid-like structures, which resemble twisted β-amyloid fibrils. The peptides form helical dimers, stabilized by packing of small and apolar residues, and the dimers further assemble into cross-α amyloid-like fibrils with superhelical pitches ranging from 170 Å to 200 Å. When a small residue that appeared critical for packing was converted to leucine, it resulted in structural rearrangement to a helical poly

SUBMITTER: Zhang SQ 

PROVIDER: S-EPMC6497057 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature