Collision-induced dissociation of branched oligosaccharide ions with analysis and calculation of relative dissociation thresholds.
Collision-induced dissociation (CID) is used in an external source Fourier transform mass spectrometer (FTMS) equipped with matrix-assisted laser desorption/ionization (MALDI) to study a number of complex, branched oligosaccharides. The relative dissociation thresholds for various oligosaccharide fragmentation pathways have been calculated in terms of kinetic and center-of-mass frame energy. For two isomers of difucosyllacto-N-hexaose, the loss of the fucose sugar is always the lowest energy fragment observed and occurs at the same energy for both isomers when the oligosaccharide is coordinated to a sodium ion. When the oligosaccharide is complexed to cesium, the threshold for the removal of the fucose moiety increases, indicating that the cesium is involved in a coordination complex that stabilizes the sugar. MS/ MS/MS is performed on a sugar, mannose core, which does not readily fragment during MALDI. In all the sugars examined, CID produces additional structural information relative to MALDI/FTMS.
Penn
S G
SG
Department of Chemistry, University of California, Davis 95616, USA.
Cancilla
M T
MT
Lebrilla
C B
CB
D002240:Carbohydrate Sequence; D007700:Kinetics; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D009844:Oligosaccharides