High field 17O solid-state NMR study of alanine tripeptides.
(17)O chemical shifts of Ala-Ala-Ala, with parallel and anti-parallel beta-sheet structures, are observed using a 930-MHz high-resolution solid-state NMR spectrometer. Ala-Ala-Ala serves as a model sheet-forming peptide because it can be easily prepared as either a parallel or an anti-parallel beta-sheet structure. Spectral differences between the two samples are observed which arise from molecular packing differences between the two sheet structures. DFT chemical shift calculations are performed for the two samples, and the calculated spectra are in good agreement with the experimental spectra. The DFT calculations provide insight into the nature of the chemical shift differences observed between the two sheet structures.
Department of Biotechnology, Tokyo University of Agriculture and Technology, Naka-cho 2-24-16, Koganei-shi, Tokyo, Japan.
Kazuo
K
Yamauchi
Michi
M
Okonogi
Hiromichi
H
Kurosu
Masataka
M
Tansho
Tadashi
T
Shimizu
Terry
T
Gullion
Tetsuo
T
Asakura
D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D009842:Oligopeptides / Q000737:chemistry*; D010103:Oxygen Isotopes; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary
D009842:Oligopeptides; D010103:Oxygen Isotopes; D010455:Peptides; C039944:alanyl-alanyl-alanine