Three-dimensional structure determination of a uniformly labeled molecule by frequency-selective dipolar recoupling under magic-angle spinning.
The complete three-dimensional (3D) structure of a glycylisoleucine (Gly-Ile) molecule was determined by individually measuring six dihedral angles with a frequency-selective homonuclear dipolar recoupling method, R2TR (rotational resonance in the tilted rotating frame), using a powder sample of diluted uniformly 13C,15N-labeled Gly-Ile. Each dihedral angle was obtained by recoupling a dipolar interaction between three or four bonds distant spins concerned or observing a dipolar correlation 2D powder pattern. The 3D structure of a Gly-Ile molecule was also determined by X-ray crystallography, and a good agreement with the NMR result was obtained. The results demonstrate that the R2TR method in a uniformly labeled powder sample can provide the 3D structure without the need to prepare a lot of selectively labeled samples.
Department of Chemistry, Graduate School of Science, Kyoto University, Japan.
K
K
Nomura
K
K
Takegoshi
T
T
Terao
K
K
Uchida
M
M
Kainosho
D002247:Carbon Isotopes; D004151:Dipeptides / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry*; D007532:Isoleucine / Q000737:chemistry*; D015394:Molecular Structure; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*
D002247:Carbon Isotopes; D004151:Dipeptides; D009587:Nitrogen Isotopes; D007532:Isoleucine; D005998:Glycine