Solution dynamics of the oligosaccharide moiety of ganglioside GM1: comparison of solution conformations with the bound state conformation in association with cholera toxin B-pentamer.

The solution dynamics of the oligosaccharide moiety of ganglioside GM1 have been determined by use of a combination of 1H rotating frame Overhauser effect measurements and restrained molecular dynamics simulations. It is found that the Galbeta1-3 and NeuNAc moieties which are primarily recognized by cholera toxin both exhibit considerable torsional flexibility about their respective glycosidic linkages. A comparison with the bound state conformation of the ganglioside in association with cholera toxin B-pentamer, shows that a low energy conformation of the oligosaccharide, which closely approximates the global minimum, is selected upon binding.