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Updated: Aug 16, 2026

Solid-phase Submonomer Synthesis of Peptoid Polymers and their Self-Assembly into Highly-Ordered Nanosheets
Published on: November 2, 2011
Surface active properties of amphiphilic sequential isopeptides: Comparison between alpha-helical and beta-sheet
Régine Maget-Dana1, Dominique Lelièvre, André Brack
1Centre de Biophysique Moléculaire, CNRS, 45071 Orléans Cedex 2, France.
Abstract:
Poly(Leu-Lys-Lys-Leu) and poly(Leu-Lys) are sequential amphiphilic peptide isomers that adopt respectively an alpha-helical conformation and a beta-sheet structure in saline solutions and at the air/water interface. The surface active properties of LKKL and LK sequential isopeptides containing 16, 20, and n residues have been compared in order to evaluate the contributions of the alpha-helical and beta-sheet conformations. Both have a natural tendency to spread at the surface of a saline solution and the values of the equilibrium spreading pressure pi(e) lie in the same range. When dissolved in a saline solution, alpha-helical peptides diffuse faster and adsorb faster at the interface than the beta-sheet isomers. From the compression isotherms of LKKL and LK peptide monolayers it is possible to extract parameters that characterize the behavior of alpha-helical and beta-sheet conformations: beta-sheet peptide monolayers are more stable and less compressible than the monolayers formed with the alpha-helical isomers. The LK peptides differ also by their high degree of self-association at the air/water interface. Copyright 1999 John Wiley & Sons, Inc.
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