Experimental and computational infrared CD studies of prototypical peptide conformations.
The infrared vibrational circular dichroism (VCD) spectral features of prototypical peptide secondary structures were reported previously by Yasui and Keiderling [Yasui, S.C., & Keiderling, T.A. (1986) Biopolymers 25, 5]. These results demonstrated that the "random coil" peptide conformation exhibits VCD signals which are approximately mirror-image features of those exhibited by alpha-helical conformers. We report here a comparison of observed VCD spectra with those computed for several secondary structures, using the extended coupled oscillator formalism employed previously to compute VCD spectra of model DNA [Zhong et al. (1990) Biochemistry 29, 7485]. These studies suggest that the so-called random-coil peptide conformation has distinct short-range order and appears to be a left-handed, helical structure.
Birke
S S
SS
Department of Chemistry, Hunter College, City University of New York 10021.
Agbaje
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I
Diem
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D002942:Circular Dichroism; D008433:Mathematics; D010455:Peptides / Q000737:chemistry*; D011487:Protein Conformation; D013055:Spectrophotometry, Infrared; D014732:Vibration
D010455:Peptides