New Insights into alfa-GalNAc-Ser Motif: Influence of Hydrogen Bonding versus Solvent Interactions on the Preferred Conformation
- Corzana, F. 1
- Busto, J.H. 1
- Jiménez-Osés, G. 1
- Asensio, J.L. 2
- Jiménez-Barbero, J. 3
- Peregrina, J.M. 1
- Avenoza, A. 1
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1
Universidad de La Rioja
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2
Instituto de Química Orgánica General
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3
Centro de Investigaciones Biológicas
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ISSN: 0002-7863
Année de publication: 2006
Volumen: 128
Número: 45
Pages: 14640-14648
Type: Article
D'autres publications dans: Journal of the American Chemical Society
Résumé
The structural features of the mucin-type simplest model, namely, the glycopeptide α-O-GalNAc-L-Ser diamide, have been investigated by combining NMR spectroscopy, molecular dynamics simulations, and DFT calculations. In contrast to previous reports, the study reveals that intramolecular hydrogen bonds between sugar and peptide residues are very weak and, as a consequence, not strong enough to maintain the well-defined conformation of this type of molecule. In fact, the observed conformation of this model glycopeptide can be satisfactorily explained by the presence of water pockets/bridges between the sugar and the peptide moieties. Additionally, DFT calculations reveal that not only the bridging water molecules but also the surrounding water molecules in the first hydration shell are essential to keep the existing conformation. © 2006 American Chemical Society.