1. Trapping a folding intermediate of the alpha-helix: stabilization of the pi-helix
- Author
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Ross N. Chapman, Anupam Patgiri, Paramjit S. Arora, Neville R. Kallenbach, Clay Bracken, and John L. Kulp
- Subjects
chemistry.chemical_classification ,Models, Molecular ,Protein Folding ,Chemistry ,Hydrogen bond ,Circular Dichroism ,Molecular Sequence Data ,Nucleation ,Peptide ,Trapping ,Biochemistry ,Instability ,Protein Structure, Secondary ,Article ,Folding (chemistry) ,Crystallography ,Intramolecular force ,Helix ,Amino Acid Sequence ,Peptides ,Nuclear Magnetic Resonance, Biomolecular - 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.
- Published
- 2008