A conformational study of oligosaccharides investigated by tandem mass spectrometry and molecular modeling

The purpose of this paper is to introduce the simplified linkage position d etermination method using tandem mass spectrometry combined with molecular modeling study. Using low energy tandem mass spectrometric experiments and molecular modeling, it has been suggested that significant differences in g lycosidic bond cleavage may occur due not only to ionic considerations but also may have contributions from steric hindrance of the absorbance of coll ision energy, leading to a statistically higher bond cleavage for stericall y crowded linkages. Permethylated derivatives of the linkage-isomeric trisa ccharides give useful fragmentation ratios and product-ions, including a 3- linkage specific ion. The ratios of fragment ions are related to the abilit y of each linkage position in the oligosaccharide to absorb collisional ene rgy.