Enhanced signal dispersion in saturation transfer difference experiments by conversion to a 1D-STD-homodecoupled spectrum.
The saturation transfer difference (STD) experiment is a rich source of information on topological aspects of ligand binding to a receptor. The epitope mapping is based on a magnetization transfer after signal saturation from the receptor to the ligand, where interproton distances permit this process. Signal overlap in the STD spectrum can cause difficulties to correctly assign and/or quantitate the measured enhancements. To address this issue we report here a modified version of the routine experiment and a processing scheme that provides a 1D-STD homodecoupled spectrum (i.e. an experiment in which all STD signals appear as singlets) with line widths similar to those in original STD spectrum. These refinements contribute to alleviate problems of signal overlap. The experiment is based on 2D-J-resolved spectroscopy, one of the fastest 2D experiments under conventional data sampling in the indirect dimension, and provides excellent sensitivity, a key factor for the difference experiments.
Martín-Pastor
Manuel
M
Laboratorio Integral de Dinámica e Estructura de Biomoléculas José R. Carracido, Unidade de Resonancia Magnética, Edificio CACTUS, RIAIDT, Universidade de Santiago de Compostela, 15706, Santiago de Compostela, Spain.
Vega-Vázquez
Marino
M
De Capua
Antonia
A
Canales
Angeles
A
André
Sabine
S
Gabius
Hans-Joachim
HJ
Jiménez-Barbero
Jesús
J
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003198:Computer Simulation; D008956:Models, Chemical; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*