Single turn peptide alpha helices with exceptional stability in water

J Am Chem Soc. 2005 Mar 9;127(9):2974-83. doi: 10.1021/ja0456003.


Cyclic pentapeptides are not known to exist in alpha-helical conformations. CD and NMR spectra show that specific 20-membered cyclic pentapeptides, Ac-(cyclo-1,5) [KxxxD]-NH(2) and Ac-(cyclo-2,6)-R[KxxxD]-NH(2), are highly alpha-helical structures in water and independent of concentration, TFE, denaturants, and proteases. These are the smallest alpha-helical peptides in water.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Circular Dichroism
  • Drug Stability
  • Humans
  • Hydrogen Bonding
  • Models, Molecular
  • Nuclear Magnetic Resonance, Biomolecular
  • Oligopeptides / chemistry*
  • Peptide Hydrolases / chemistry
  • Peptide Hydrolases / metabolism
  • Peptides, Cyclic / chemistry*
  • Protein Denaturation
  • Protein Structure, Secondary
  • Solvents
  • Temperature
  • Water / chemistry*


  • Oligopeptides
  • Peptides, Cyclic
  • Solvents
  • Water
  • Peptide Hydrolases