Amide I vibrational circular dichroism of dipeptide: Conformation dependence and fragment analysis.
The amide I vibrational circular dichroic response of alanine dipeptide analog (ADA) was theoretically investigated and the density functional theory calculation and fragment analysis results are presented. A variety of vibrational spectroscopic properties, local and normal mode frequencies, coupling constant, dipole, and rotational strengths, are calculated by varying two dihedral angles determining the three-dimensional ADA conformation. Considering two monopeptide fragments separately, we show that the amide I vibrational circular dichroism of the ADA can be quantitatively predicted. For several representative conformations of the model ADA, vibrational circular dichroism spectra are calculated by using both the density functional theory calculation and fragment analysis methods.
Department of Chemistry and Center for Multidimensional Spectroscopy, Division of Chemistry and Molecular Engineering, Korea University, Seoul 136-701, Korea.
Jun-Ho
JH
Choi
Minhaeng
M
Cho
D000577:Amides / Q000032:analysis / Q000737:chemistry*; D002942:Circular Dichroism / Q000379:methods; D003198:Computer Simulation; D004151:Dipeptides / Q000032:analysis / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D010446:Peptide Fragments / Q000737:chemistry*; D011487:Protein Conformation; D014732:Vibration
D000577:Amides; D004151:Dipeptides; D010446:Peptide Fragments