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Nucleation effects in peptide foldamers.

ABSTRACT: Oligomers composed of ?(3)-amino acid residues and a mixture of ?- and ?(3)-residues have emerged as proteolytically stable structural mimics of ?-helices. An attractive feature of these oligomers is that they adopt defined conformations in short sequences. In this manuscript, we evaluate the impact of ?(3)-residues as compared to their ?-amino acid analogs in prenucleated helices. Our hydrogen-deuterium exchange results suggest that heterogeneous sequences composed of "????" repeats are conformationally more rigid than the corresponding homogeneous ?-peptide helices, with the macrocycle templating the helical conformation having a significant influence.

SUBMITTER: Patgiri A

PROVIDER: S-EPMC3399945 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Nucleation effects in peptide foldamers.

Patgiri Anupam A Joy Stephen T ST Arora Paramjit S PS

Journal of the American Chemical Society 20120705 28

Oligomers composed of β(3)-amino acid residues and a mixture of α- and β(3)-residues have emerged as proteolytically stable structural mimics of α-helices. An attractive feature of these oligomers is that they adopt defined conformations in short sequences. In this manuscript, we evaluate the impact of β(3)-residues as compared to their α-amino acid analogs in prenucleated helices. Our hydrogen-deuterium exchange results suggest that heterogeneous sequences composed of "αααβ" repeats are conform ...[more]

PMID: 22715982

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