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Updated: Mar 19, 2026

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
12/14/14-Helix Formation in 2:1 α/β-Hybrid Peptides Containing Bicyclo[2.2.2]octane Ring Constraints
Baptiste Legrand1, Christophe André1, Laure Moulat1
1Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS-Université Montpellier-ENSCM, 15 avenue Charles Flahault, 34093, Montpellier, cedex 5, France.
Abstract:
The highly constrained β-amino acid ABOC induces different types of helices in β urea and 1:1 α/β amide oligomers. The latter can adopt 11/9- and 18/16-helical folds depending on the chain length in solution. Short peptides alternating proteinogenic α-amino acids and ABOC in a 2:1 α/β repeat pattern adopted an unprecedented and stable 12/14/14-helix. The structure was established through extensive NMR, molecular dynamics, and IR studies. While the 1:1 α-AA/ABOC helices diverged from the canonical α-helix, the helix formed by the 9-mer 2:1 α/β-peptide allowed the projection of the α-amino acid side chains in a spatial arrangement according to the α-helix. Such a finding constitutes an important step toward the conception of functional tools that use the ABOC residue as a potent helix inducer for biological applications.
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