NMR evidence for the nucleation of a β-hairpin peptide conformation in water by an Asn-Gly type I′ β-turn sequence

The contribution of the beta-turn sequence to the folding and stability of a peptide beta-hairpin in water has been analysed from studies of a truncated peptide lacking one beta-strand and hence the majority of the interstrand hydrophobic interactions; NMR analysis shows that the Asn-Gly type I' beta-turn conformation is significantly populated, suggesting that the intrinsic conformation preference of the turn sequence may play an important role in nucleating hairpin folding.