【摘 要】
：
Five hybrid tetrapeptides,each consisting a central dipeptide segment of α-amino acid residues flanked by two aromatic γ-amino acid residues,are found to fold into well-definedβ-hairpin conformations as shown by NMR,computational study,and X-ray structure
【机 构】
：
College of Chemistry,Beijing Normal University,Beijing 100875,China;Department of Chemistry,Universi
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Five hybrid tetrapeptides,each consisting a central dipeptide segment of α-amino acid residues flanked by two aromatic γ-amino acid residues,are found to fold into well-definedβ-hairpin conformations as shown by NMR,computational study,and X-ray structures.The turn loop of thisβ-hairpin motif ac-commodates different two-residue α-amino acid sequences from the highly flexible Gly-Gly,to the more restricted D-Pro-Gly.The presence of α-amino acid side chains enhances the stabilities of the β-hairpins with the exception of D-Pro-Gly-which results in destabilization.Based on this hairpin/turn motif,a va-riety of different dipeptide sequences of α-amino acids which rarely occur inβ-turns can be introduced and presented as two-residue loops.
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