title: Thermodynamic evidence for Ca2+-mediated self-aggregation of Lewis X gold glyconanoparticles. A model for cell adhesion via carbohydrate-carbohydrate interaction.
abstract: Thermodynamic evidence for the selective Ca(2+)-mediated self-aggregation via carbohydrate-carbohydrate interactions of gold glyconanoparticles functionalized with the disaccharides lactose (lacto-Au) and maltose (malto-Au), or the biologically relevant trisaccharide Lewis X (Le(X)-Au), was obtained by isothermal titration calorimetry. The aggregation process was also directly visualized by atomic force microscopy. It was shown in the case of the trisaccharide Lewis X that the Ca(2+)-mediated aggregation is a slow process that takes place with a decrease in enthalpy of 160 +/- 30 kcal mol(-)(1), while the heat evolved in the case of lactose and maltose glyconanoparticles was very low and thermal equilibrium was quickly achieved. Measurements in the presence of Mg(2+) and Na(+) cations confirm the selectivity for Ca(2+) of Le(X)-Au glyconanoparticles. The relevance of this result to cell-cell adhesion process mediated by carbohydrate-carbohydrate interactions is discussed.
authors.affiliation: Grupo de Carbohidratos, Laboratory of Glyconanotechnology, IIQ/CSIC, Americo Vespucio 49, 41092 Seville, Spain.
authors.forename: Jesús M
authors.initials: JM
authors.lastname: de la Fuente
authors.forename: Peter
authors.initials: P
authors.lastname: Eaton
authors.forename: Africa G
authors.initials: AG
authors.lastname: Barrientos
authors.forename: Margarita
authors.initials: M
authors.lastname: Menéndez
authors.forename: Soledad
authors.initials: S
authors.lastname: Penadés
mesh_terms: D000818:Animals; D002118:Calcium / Q000737:chemistry*; D002151:Calorimetry / Q000379:methods; D002240:Carbohydrate Sequence; D002413:Cations, Divalent / Q000737:chemistry; D002448:Cell Adhesion / Q000502:physiology; D002642:Chick Embryo; D006046:Gold / Q000737:chemistry*; D007785:Lactose / Q000737:chemistry; D016256:Lewis X Antigen / Q000031:analogs & derivatives; D008274:Magnesium / Q000737:chemistry; D008320:Maltose / Q000737:chemistry; D018625:Microscopy, Atomic Force; D008969:Molecular Sequence Data; D049329:Nanostructures / Q000737:chemistry*; D009474:Neurons / Q000166:cytology; D009844:Oligosaccharides / Q000737:chemistry; D011161:Porifera / Q000166:cytology; D012160:Retina / Q000166:cytology; D013816:Thermodynamics; D014312:Trisaccharides / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D016256:Lewis X Antigen; D009844:Oligosaccharides; D014312:Trisaccharides; C110530:galactosyl-(1,4)-fucopyranosyl-(1,3)-N-acetylglucosamine; D008320:Maltose; D006046:Gold; D008274:Magnesium; D007785:Lactose; D002118:Calcium