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Structural mimicry of the ?-helix in aqueous solution with an isoatomic ?/?/?-peptide backbone.

ABSTRACT: Artificial mimicry of ?-helices offers a basis for development of protein-protein interaction antagonists. Here we report a new type of unnatural peptidic backbone, containing ?-, ?-, and ?-amino acid residues in an ?????? repeat pattern, for this purpose. This unnatural hexad has the same number of backbone atoms as a heptad of ? residues. Two-dimensional NMR data clearly establish the formation of an ?-helix-like conformation in aqueous solution. The helix formed by our 12-mer ?/?/?-peptide is considerably more stable than the ?-helix formed by an analogous 14-mer ?-peptide, presumably because of the preorganized ? and ? residues employed.

SUBMITTER: Sawada T

PROVIDER: S-EPMC3141811 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Structural mimicry of the α-helix in aqueous solution with an isoatomic α/β/γ-peptide backbone.

Sawada Tomohisa T Gellman Samuel H SH

Journal of the American Chemical Society 20110426 19

Artificial mimicry of α-helices offers a basis for development of protein-protein interaction antagonists. Here we report a new type of unnatural peptidic backbone, containing α-, β-, and γ-amino acid residues in an αγααβα repeat pattern, for this purpose. This unnatural hexad has the same number of backbone atoms as a heptad of α residues. Two-dimensional NMR data clearly establish the formation of an α-helix-like conformation in aqueous solution. The helix formed by our 12-mer α/β/γ-peptide is ...[more]

PMID: 21520956

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