Chemoenzymic synthesis of sialylated and fucosylated oligosaccharides having an N-acetyllactosaminyl core.
Several sialylated and fucosylated oligosaccharides, based upon the N-acetyllactosaminyl core structure, have been synthesized from a single trisaccharide glycoside, beta-D-GlcNAc-(1-->3)-beta-D-Gal-(1-->4)-beta-D-GlcNAc-OCH2(CH2)++ +7CO2CH3, by the sequential use of several glycosyltransferases and one sialidase. In these chemoenzymic syntheses, selective internal monofucosylation of a dimeric N-acetyl-lactosaminyl tetrasaccharide is achieved via two routes. It is demonstrated that the pentasaccharide beta-D-Gal-(1-->4)-beta-D-GlcNAc-(1-->3)-beta-D-Gal-(1-->4)-[alpha- L-Fuc-(1-->3)]-beta-D-GlcNAc-OCH2(CH2)7-CO2CH3 is an acceptor for the rat liver beta-D-Gal-(1-->3/4)-D-Glc-NAc alpha 2,3- and beta-D-Gal-(1-->4)-D-GlcNAc alpha 2,6-sialyltransferases. Among the structures obtained is the terminal hexasaccharide of the CD-65/VIM-2 epitope.
Kashem
M A
MA
Alberta Research Council, Carbohydrate Research Program, Edmonton, Canada.
Wlasichuk
K B
KB
Gregson
J M
JM
Venot
A P
AP
D002240:Carbohydrate Sequence; D005643:Fucose / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D019158:N-Acetylneuraminic Acid; D009844:Oligosaccharides / Q000138:chemical synthesis*; D012794:Sialic Acids / Q000737:chemistry*
D009844:Oligosaccharides; D012794:Sialic Acids; D005643:Fucose; D019158:N-Acetylneuraminic Acid