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Selective aromatic interactions in beta-hairpin peptides.

Chad D Tatko·Marcey L Waters
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Abstract

To probe the selectivity possible in hydrophobic clusters, we have compared the cross-strand interactions of phenylalanine (Phe) and cyclohexylalanine (Cha) in a beta-hairpin peptide. We have found a preference for self-association among the aromatic residues, which provides 0.55 kcal/mol in stability relative to Cha-Cha cross-strand pair. NMR analysis of the Phe-Phe cross-strand pair indicates that it interacts in an edge-face interaction, despite the fact that it is highly solvent-exposed. The interaction geometry as well as the enthalpic and entropic values for the peptide containing the Phe-Phe cross-strand pair suggest that the preference for self-association arises from inherent differences in the nature of aromatic and aliphatic interactions in water.

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PeptidesStatic ElectricityThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Chad D Tatko, Marcey L Waters. 2002-08-14. Selective aromatic interactions in beta-hairpin peptides.. https://doi.org/10.1021/ja0262481

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