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An alpha/beta-peptide helix bundle with a pure beta3-amino acid core and a distinctive quaternary structure.

ABSTRACT: Helix bundles are among the most widely studied tertiary and quaternary structural motifs in proteins. Here we present the crystal structure of an alpha/beta-peptide foldamer that adopts a tetrameric helix-bundle quaternary structure with a hydrophobic core composed solely of beta-amino acids. The structure displays features that are unprecedented among all known helix bundles composed of either alpha-peptides or peptidic foldamers. The tetramer is characterized by an asymmetry of interaction between neighboring helices, and the side-chain packing within the hydrophobic core differs fundamentally from the knobs-into-holes arrangement typical of most helix bundles.

SUBMITTER: Giuliano MW

PROVIDER: S-EPMC2724756 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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An alpha/beta-peptide helix bundle with a pure beta3-amino acid core and a distinctive quaternary structure.

Giuliano Michael W MW Horne W Seth WS Gellman Samuel H SH

Journal of the American Chemical Society 20090701 29

Helix bundles are among the most widely studied tertiary and quaternary structural motifs in proteins. Here we present the crystal structure of an alpha/beta-peptide foldamer that adopts a tetrameric helix-bundle quaternary structure with a hydrophobic core composed solely of beta-amino acids. The structure displays features that are unprecedented among all known helix bundles composed of either alpha-peptides or peptidic foldamers. The tetramer is characterized by an asymmetry of interaction be ...[more]

PMID: 19580264

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