title: Semisynthetic preparation of N-glycolylneuraminic acid containing GM1 ganglioside: chemical characterization, physico-chemical properties and some biochemical features.
abstract: N-Glycolylneuraminic acid containing GM1, GM1(NeuGc), was prepared by semisynthetic procedure. The procedure makes use of GM1 ganglioside deacetylated at the level of sialic acid residue (deAc-GM1) and of 1,3-dioxalan-2,4-dione. DeAc-GM1 is prepared from GM1 by alkaline hydrolysis in the presence of tetramethylammonium hydroxide and the glycolylating compound by reaction of glycolic acid with phosgene in dioxane, followed by cyclization under vacuum. Mass spectrometric and nuclear magnetic resonance spectroscopy analyses clearly indicated the presence, in the neosynthesized ganglioside of a glycolic group in the sialic acid residue. Laser-light scattering measurements show that GM1(NeuGc) aggregates in aqueous media being present in solution as micelles with a molecular weight of 576,000 and a hydrodynamic radius of 62.4 A as determined at 25 degrees C. GM1(NeuGc) promotes neurite outgrowth in N-2a cells to a similar degree as GM1(NeuAc), but shows different behaviour under treatment with sialidase from Arthrobacter ureafaciens.
authors: Department of Medical Chemistry and Biochemistry, Medical School, University of Milan, Italy.
authors: S
authors: S
authors: Sonnino
authors: D
authors: D
authors: Acquotti
authors: G
authors: G
authors: Fronza
authors: L
authors: L
authors: Cantù
authors: V
authors: V
authors: Chigorno
authors: M
authors: M
authors: Pitto
authors: G
authors: G
authors: Kirschner
authors: G
authors: G
authors: Tettamanti
mesh_terms: D001173:Arthrobacter / Q000201:enzymology; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D005677:G(M1) Ganglioside / Q000138:chemical synthesis*; D008401:Gas Chromatography-Mass Spectrometry; D007202:Indicators and Reagents; D008823:Micelles; D008969:Molecular Sequence Data; D009438:Neuraminic Acids; D009439:Neuraminidase / Q000378:metabolism
chemical_list: D007202:Indicators and Reagents; D008823:Micelles; D009438:Neuraminic Acids; C032592:N-glycolylneuraminic acid; D005677:G(M1) Ganglioside; D009439:Neuraminidase