title: Use of the "core-2"-N-acetylglucosaminyltransferase in the chemical-enzymatic synthesis of a sialyl-LeX-containing hexasaccharide found on O-linked glycoproteins.
abstract: A simple preparation of the "core-II" N-acetylglucosaminyltransferase (UDP-D-GlcpNAc:beta-D-Galp-(1-->3)-alpha-D-GalpNAc (GlcNAc to GalNAc) beta-(1-->6)-GlcNAc-transferase, GlcNAcT, EC 2.4.1.102) from commercial mouse kidney acetone powder is reported. The enzyme obtained in a single step of affinity chromatography is suitable for use in preparative oligosaccharide synthesis. In conjunction with previously described preparations of beta-(1-->4)-galactosyltransferase (EC 2.4.1.22), alpha-(2-->3)-sialytransferase (EC 2.4.99.6) and alpha-(1-->3/4)-fucosyltransferase (EC 2.4.1.65), the GlcNAcT was used in the first step of a sequence which converted the disaccharide beta-D-Galp-(1-->3)-alpha-D-GalpNAc-OR into the sialyl-LeX-containing structure alpha-D-NeupAc-(2-->3)-beta-D-Galp- (1-->4)-[alpha-L-Fucp-(1-->3)]-beta-D-GlcpNAc-(1-->6)-[beta-D-Galp - (1-->3)]-alpha-D-GalpNAc-OR (5), where R = (CH2)8CO2Me. Hexasaccharide 5, thus assembled in only one week once the enzymes were prepared, was characterized by 1H and 13C NMR spectroscopy and fast-atom bombardment mass spectrometry, as were all intermediate oligosaccharides. The core II GlcNAcT thus joins the expanding repertoire of readily available reagents for the rapid assembly of oligosaccharides.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Oehrlein
authors.forename: O
authors.initials: O
authors.lastname: Hindsgaul
authors.forename: M M
authors.initials: MM
authors.lastname: Palcic
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002417:Cattle; D006023:Glycoproteins / Q000737:chemistry*; D006602:Hexosyltransferases / Q000378:metabolism; D007668:Kidney / Q000201:enzymology; D016256:Lewis X Antigen; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008969:Molecular Sequence Data; D017351:N-Acetylglucosaminyltransferases / Q000378:metabolism*; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D006023:Glycoproteins; D016256:Lewis X Antigen; D009844:Oligosaccharides; D006602:Hexosyltransferases; D017351:N-Acetylglucosaminyltransferases; C053024:beta-1,3-galactosyl-O-glycosyl-glycoprotein beta-1,6-acetylglucosaminyl transferase