Título: NMR characterization of differential binding of sugar anomers by lectins
Autor: El Biari, Khouzaima; Calle Jiménez, Luis Pablo; Ribeiro, João P.; Jiménez-Barbero, Jesús; Cañada, F. Javier; Dierks, T.; André, Sabine; Gabius, Hans-Joachim
Resumen: Reducing carbohydrates can be characterized in two different structures depending of
the configuration at the anomeric position of the reducing end. Anomeric selectivity has been
observed and studied in enzymes involved in carbohydrate transformations by diverse kinetic
approaches since long time ago1, however those approaches are not possible in the case of
just binding studies of carbohydrate in solution. Lectins and other carbohydrates receptors do
not modified their ligands, thus do not generate time dependent responses feasible of
monitoring. Taking into account that free anomers equilibrate in no more than a few hours,
many of the available biophysical techniques in solution only provide a mean macroscopic
view of the recognition event involving the mixture of anomers in equilibrium. The direct
discrimination of the recognition of each anomer is not an easy task, and NMR can be
technique of choice because it allows observing independent signals for each anomer in spite
of they are in chemical equilibrium exchange. In fact, 13C NMR has been used to show the -
anomer preference of bacterial chemotaxis sugar binding proteins 2 and more exotic tritium 3H
-NMR has been used to study anomeric preference in maltose binding protein 3. In the present
work we have applied STD–NMR strategies, to obtain quantitative information on the
individual interaction of each anomer, combined with molecular modeling in order to
characterize the differential monosaccharide anomer affinity by some selected lectins.
Descripción: 1 p.
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