Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5407358 | Journal of Magnetic Resonance | 2007 | 9 Pages |
Abstract
5-Fluoro-dl-tryptophan (5F-Trp) is a very sensitive probe used to investigate orientation and dynamics of biomacromolecules at the in situ level. In order to establish a 19F NMR strategy, the crystal structure and 19F chemical shielding tensor of 5F-Trp are reported. A novel approach was developed to use F-F homonuclear dipole-dipole coupling information to analyze single-crystal NMR data without determining crystal orientations. The measured values for the principal components of the shielding tensor are Ï11Â =Â 0.9, Ï22Â =Â â63.3, and Ï33Â =Â â82.9Â ppm relative to TFA in D2O. The principal axes of the shielding tensors coincide with the indole ring symmetry, which makes it a straightforward and powerful tool to monitor protein alignment in oriented environments. Hartree-Fock (HF) and density functional theory (DFT) calculations of the chemical shielding tensors are also reported.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Xingang Zhao, Jeffrey S. DeVries, Robert McDonald, Brian D. Sykes,