Characterization of the Galectin-1 Carbohydrate Recongnition Domain in termms of Solvent Occupancy

DI LELLA, SANTIAGO; MARTÍ, MARCELO A.; ÁLVAREZ, MA. ROSA; ESTRÍN, DARÍO A.; DÍAZ RICCI, JUAN C.

JOURNAL OF PHYSICAL CHEMISTRY B

American Chemical Society

Lugar: Washington DC, USA; Año: 2007 vol. 12 p. 130 - 145

1089-5647

Human Galectin-1, a galactosil-terminal sugar binding soluble protein, is a potent multifunctional effector that participates in specific protein-carbohydrate and protein-protein interactions. Recent studies revealed that it plays a key role as a modulator of cellular differentiation and immunological response. In this work, we have investigated the solvation properties of the carbohydrate recognition domain (CRD) of Gal-1 by means of molecular dynamics simulations. Water sites (ws) were identified in terms of radial and angular distribution functions, and properties such as water residence times, interaction energies and free-energy contributions were evaluated for those sites. Our results allowed us to correlate the thermodynamic properties of the ws and their binding pattern with the N-acetilgalactoside ligand. These results let us further infer that the water molecules located at the ws, which exhibit much more favorable binding free energies, are the ones replaced by -OH groups of the sugar.