title: Evidence for linkage position determination in cobalt coordinated pentasaccharides using ion trap mass spectrometry.
abstract: A methodology to determine the linkage position of oligosaccharides is presented. In order to illustrate this technique, several oligosaccharides and disaccharides were ionized by electrospray and analyzed in a Paul trap mass spectrometer. Multiple stage tandem mass spectrometry experiments were used to determine linkage and structural information for the following four cobalt coordinated and singly charged ([M + Co-H]+) pentasaccharides: Lacto-N-fucopentaose I, II, III, and V. In order to differentiate between linkage positions, multiple low energy collision induced experiments with mass selected C type ions have been carried out in an ion trap mass spectrometer. Because of the coordination with cobalt, which directs the dissociation pathways, these C type ions undergo specific fragmentation reactions upon low energy collision induced dissociation. These dissociation pathways are unambiguously dependent on their linkage position, thus allowing differentiation between 1-->2, 1-->3, 1-->4, and 1-->6 linkage positions throughout the oligomers. Studies on various linked disaccharides and N-acetyl-disaccharides, which are smaller constituents of the pentasaccharides, were used to verify and confirm the results obtained from the pentasaccharides.
authors.affiliation: College of Chemistry, University of California, Berkeley 94720-1460, USA.
authors.forename: S
authors.initials: S
authors.lastname: König
authors.forename: J A
authors.initials: JA
authors.lastname: Leary
mesh_terms: D002240:Carbohydrate Sequence; D003035:Cobalt / Q000737:chemistry*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*
chemical_list: D009844:Oligosaccharides; D003035:Cobalt