title: Energy-resolved structural details obtained from gangliosides.
abstract: Gangliosides, a family of glycosphingolipids (GSLs) that comprise sialic acid residue(s), are an important class of molecules that exist on the outer surface of the plasma membrane. To assess the functions of a particular series of gangliosides that play important roles in brain functions, their structures and localizations need to be investigated. We studied the structures of these gangliosides by collision-induced dissociation using quadrupole ion-trap mass spectrometry. The dissociation processes were investigated in detail based on energy-resolved mass spectrometry using sodiated molecules. The decision of utilization of the positive mode was based on the assumption that it was the generally applicable method for GSLs, including neutral ones. In this investigation, sialic acid residues were esterified to stabilize the linkages and to generate multiple fragment ions for successful structural investigations. A detailed analysis of a series of sodiated species of gangliosides based on energy-resolved mass spectrometry revealed that the GM1-equivelent fragments generated from the precursor ions under low energy CID conditions had the structural characteristics of their individual precursors. It was suggested that this information will be useful in determining the structures of their precursor gangliosides.
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4529 Nagatsuta-cho, Midori-ku, Yokohama 226-0018, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Shioiri
authors.forename: Ayako
authors.initials: A
authors.lastname: Kurimoto
authors.forename: Takuro
authors.initials: T
authors.lastname: Ako
authors.forename: Shusaku
authors.initials: S
authors.lastname: Daikoku
authors.forename: Atsuko
authors.initials: A
authors.lastname: Ohtake
authors.forename: Hideharu
authors.initials: H
authors.lastname: Ishida
authors.forename: Makoto
authors.initials: M
authors.lastname: Kiso
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Suzuki
authors.forename: Osamu
authors.initials: O
authors.lastname: Kanie
mesh_terms: D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002518:Ceramides / Q000737:chemistry; D005732:Gangliosides / Q000737:chemistry*; D006027:Glycosides / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D019158:N-Acetylneuraminic Acid / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D002518:Ceramides; D005732:Gangliosides; D006027:Glycosides; D019158:N-Acetylneuraminic Acid