Characterization of the sulfated fucose-containing trisaccharides by fast atom bombardment tandem mass spectrometry in the study of the acrosome reaction-inducing substance of the starfish, Asterias amurensis

Fast atom bombardment mass spectrometry (FABMS) and collision-induced dissociation tandem mass spectrometry (CID-MS/MS) were applied to the investigation of the anomeric isomerism of synthetic trisaccharides consisting of xylose, galactose and sulfated fucose {Xyl1--3Gal alpha 1--3(4-OSO3Na)Fuc} and {Xyl1--3Gal alpha 1--4(3-OSO3Na)Fuc} and the linkage position of the sulfate group. It was possible to differentiate between various glycosidic linkages in several synthetic trisaccharides. The position of a sulfate group in synthetic methyl O-sulfo-alpha-L-fucopyranoside isomers was elucidated from the fragmentation patterns. Comparing the data from the synthetic sulfated trisaccharides with the spectra from the natural compound derived from glycan chains of the acrosome reaction-inducing substance (ARIS) from starfish, the anomeric structure and the position of the sulfate group in the natural sample were determined without ambiguity as Xyl beta 1--3Gal alpha 1--3(4-OSO3-)Fuc, in agreement with the result from an independent study based on nuclear magnetic resonance.