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Square channels formed by a peptide derived from transthyretin.

ABSTRACT: High-resolution structures of peptide supramolecular assemblies are key to understanding amyloid diseases and designing peptide-based materials. This paper explores the supramolecular assembly of a macrocyclic ?-sheet peptide derived from transthyretin (TTR). The peptide mimics the ?-hairpin formed by the ?-strands G and H of TTR, which form the interface of the TTR tetramer. X-ray crystallography reveals that the peptide does not form a tetramer, but rather assembles to form square channels. The square channels are formed by extended networks of ?-sheets and pack in a "tilted windows" pattern. This unexpected structure represents an emergent property of the peptide and broadens the scope of known supramolecular assemblies of ?-sheets.

SUBMITTER: Yoo S

PROVIDER: S-EPMC5355858 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Square channels formed by a peptide derived from transthyretin.

Yoo Stan S Kreutzer Adam G AG Truex Nicholas L NL Nowick James S JS

Chemical science 20160801 12

High-resolution structures of peptide supramolecular assemblies are key to understanding amyloid diseases and designing peptide-based materials. This paper explores the supramolecular assembly of a macrocyclic β-sheet peptide derived from transthyretin (TTR). The peptide mimics the β-hairpin formed by the β-strands G and H of TTR, which form the interface of the TTR tetramer. X-ray crystallography reveals that the peptide does not form a tetramer, but rather assembles to form square channels. Th ...[more]

PMID: 28451128

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