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Trapping a folding intermediate of the alpha-helix: stabilization of the pi-helix.

ABSTRACT: We report the design, synthesis, and characterization of a short peptide trapped in a pi-helix configuration. This high-energy conformation was nucleated by a preorganized pi-turn, which was obtained by replacing an N-terminal intramolecular main chain i and i + 5 hydrogen bond with a carbon-carbon bond. Our studies highlight the nucleation parameter as a key factor contributing to the relative instability of the pi-helix and allow us to estimate fundamental helix-coil transition parameters for this conformation.

SUBMITTER: Chapman R

PROVIDER: S-EPMC7183248 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Trapping a folding intermediate of the alpha-helix: stabilization of the pi-helix.

Chapman Ross R Kulp John L JL Patgiri Anupam A Kallenbach Neville R NR Bracken Clay C Arora Paramjit S PS

Biochemistry 20080313 14

We report the design, synthesis, and characterization of a short peptide trapped in a pi-helix configuration. This high-energy conformation was nucleated by a preorganized pi-turn, which was obtained by replacing an N-terminal intramolecular main chain i and i + 5 hydrogen bond with a carbon-carbon bond. Our studies highlight the nucleation parameter as a key factor contributing to the relative instability of the pi-helix and allow us to estimate fundamental helix-coil transition parameters for ...[more]

PMID: 18335996

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