title: Structural elucidation of underivatized gangliosides by electrospray-ionization tandem mass spectrometry (ESIMS/MS).
abstract: The structural characterization of intact polysialogangliosides by electrospray-ionization mass spectrometry (ESIMS) and tandem mass spectrometry (MS/MS) is described. The negative-ion ESI mass spectra of gangliosides, such as a tetrasialoganglioside GQ1b, showed molecularly related ions with high sensitivity and accuracy. Collision-induced dissociation (CID) MS/MS provided adequate information to characterize the number and positions of sialic acids. ESIMS and CIDMS/MS techniques were applied successfully also in the positive-ion mode for characterization of intact gangliosides. Two isomeric disialogangliosides, GD1a and GD1b, are distinguishable from one another by CIDMS/MS in both negative- and positive-ion modes. The technique is readily applicable to structural analyses such as determining the positional isomers of glycoconjugates.
authors.affiliation: Frontier Research Program, Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ii
authors.forename: Y
authors.initials: Y
authors.lastname: Ohashi
authors.forename: Y
authors.initials: Y
authors.lastname: Nagai
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002417:Cattle; D005732:Gangliosides / Q000737:chemistry*; D006001:Glycoconjugates / Q000737:chemistry; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D015394:Molecular Structure; D012794:Sialic Acids / Q000737:chemistry
chemical_list: D005732:Gangliosides; D006001:Glycoconjugates; D012794:Sialic Acids; C025447:sialogangliosides