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Environment- and sequence-dependence of helical type in membrane-spanning peptides composed of ?3-amino acids.

ABSTRACT: Transmembrane (TM) ?-peptides comprised of acyclic ?(3)-amino acids demonstrate equilibrium between 12- and 14-helical structures in an environment- and sequence-dependent manner. Circular dichroism (CD) spectra of TM ?(3)-peptides may be described as linear combinations of the 12- and 14-helical CD spectra. The apparent malleability of ?(3)-substituted acyclic ?-peptides has practical implications for foldamer design, as it suggests that both the 14-helix and 12-helix might be reasonable platforms for molecular recognition.

SUBMITTER: Korendovych IV

PROVIDER: S-EPMC3124938 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Environment- and sequence-dependence of helical type in membrane-spanning peptides composed of β3-amino acids.

Korendovych Ivan V IV Shandler Scott J SJ Montalvo Geronda L GL DeGrado William F WF

Organic letters 20110609 13

Transmembrane (TM) β-peptides comprised of acyclic β(3)-amino acids demonstrate equilibrium between 12- and 14-helical structures in an environment- and sequence-dependent manner. Circular dichroism (CD) spectra of TM β(3)-peptides may be described as linear combinations of the 12- and 14-helical CD spectra. The apparent malleability of β(3)-substituted acyclic β-peptides has practical implications for foldamer design, as it suggests that both the 14-helix and 12-helix might be reasonable platfo ...[more]

PMID: 21651308

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