?-Sheet 13C structuring shifts appear only at the H-bonded sites of hairpins.
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ABSTRACT:
SUBMITTER: Shu I
PROVIDER: S-EPMC3146544 | biostudies-literature | 2011 Feb
REPOSITORIES: biostudies-literature
Publications
β-Sheet 13C structuring shifts appear only at the H-bonded sites of hairpins.
Shu Irene I Stewart James M JM Scian Michele M Kier Brandon L BL Andersen Niels H NH
Journal of the American Chemical Society 20110107 5
The (13)C chemical shifts measured for designed β-hairpins indicate that the structuring shifts (upfield for Cα and C', downfield for Cβ) previously reported as diagnostic for β-structuring in proteins appear only at the H-bonded strand residues. The resulting periodicity of structuring shift magnitudes is not, however, a consequence of H-bonding status; rather, it reflects a previously unrecognized alternation in the backbone torsion angles of β-strands. This feature of hairpins is also likely ...[more]
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