Differentiation of type 1 and type 2 chain linkages of native glycosphingolipids by positive-ion fast-atom bombardment mass spectrometry with collision-induced dissociation and linked scanning.
Two underivatized glycosphingolipids, Le(b) and Le(y), isomeric in carbohydrate structure (Fuc alpha 1-->2Gal beta 1--> 3[Fuc alpha 1-->4]GlcNAc beta 1-->3Gal beta 1-->4Glc beta 1-->1Cer and Fuc alpha 1-->2Gal beta 1-->4[Fuc alpha 1-->3]GlcNAc beta 1-->3Gal beta 1--> 4Glc beta 1-->1Cer, respectively), were analyzed by positive-ion fast-atom bombardment (FAB) mass spectrometry with high energy collision-induced dissociation (CID) and linked scanning. The two isomers were distinguishable by the abundance of product ions derived from the non-reducing terminal tetrasaccharide fragment via sequential beta-eliminations of vicinally linked saccharide residues. Following earlier studies from other laboratories, which have dealt primarily with positive-ion FAB-CID mass spectrometry of simple model oligosaccharides, these results exemplify the practical application of two-sector methodology to underivatized complex glycoconjugates commonly encountered in the biomedical field.
Salyan
M E
ME
Biomembrane Institute, Seattle, WA 98119.
Stroud
M R
MR
Levery
S B
SB
D002236:Carbohydrate Conformation; D005647:Fucosyltransferases / Q000378:metabolism; D006028:Glycosphingolipids / Q000032:analysis* / Q000096:biosynthesis; D007536:Isomerism; D016339:Spectrometry, Mass, Fast Atom Bombardment
D006028:Glycosphingolipids; D005647:Fucosyltransferases