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