Coherent two dimensional infrared spectroscopy of a cyclic decapeptide antamanide. A simulation study of the amide-I and A bands

J Phys Chem B. 2008 Oct 2;112(39):12479-90. doi: 10.1021/jp801493y. Epub 2008 Sep 9.

Abstract

The two-dimensional infrared photon echo spectrum of Antamanide (- (1)Val- (2)Pro- (3)Pro- (4)Ala- (5)Phe- (6)Phe- (7)Pro- (8)Pro- (9)Phe- (10)Pro-) in chloroform is calculated using an explicit solvent molecular dynamics (MD) simulation combined with a density functional theory (DFT) map for the effective vibrational Hamiltonian. Evidence for a strong intramolecular hydrogen bonding network is found. Comparison with experimental absorption allows the identification of the dominant conformation. Multidimensional spectroscopy reveals intramolecular couplings and gives information on its dynamics. A two-color amide-I and amide-A crosspeak is predicted and analyzed in terms of local structure.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Absorption
  • Amides / chemistry*
  • Amino Acid Sequence
  • Color
  • Hydrogen Bonding
  • Models, Molecular
  • Peptides, Cyclic / chemistry*
  • Protein Conformation
  • Solvents / chemistry
  • Spectrophotometry, Infrared

Substances

  • Amides
  • Peptides, Cyclic
  • Solvents
  • antamanide