Carbohydrate recognition of gramicidin S analogues in aqueous medium

We have designed and synthesized of carbohydrate-binding peptides, gramicidin S analogues. Asn/Asp/Gln and Trp residues in the peptides were employed as the binding sites for carbohydrates by hydrogen-bonding interaction and the creation units for hydrophobic pocket to promote the interaction, respectively. The data of fluorescence spectroscopy and affinity column chromatography indicated that the peptides possessed the binding ability for some carbohydrates in aqueous medium. As a result of 1H NMR study, nuclear Overhauser effects between aromatic side chains of a peptide, [Gln1,1′,Trp3,3′]-gramisidin S and mannose were observed, indicating that the interaction of the peptide with the sugar occurred in the hydrophobic environment formed by Trp and Phe residues.