title: All-aqueous, regiospecific transglycosylation synthesis of 3-O-alpha-L-fucopyranosyl-2-acetamido-2-deoxy-D-glucopyranose, a building block for the synthesis of branched oligosaccharides.
abstract: A transglycosylation reaction, carried out in an aqueous medium and catalyzed by a crude preparation of alpha-fucosidase (E.C. 3.2.1.51) from Aspergillus niger, allowed for the regiospecific synthesis of the disaccharide 3-O-alpha-L-fucopyranosyl-2-acetamido-2-deoxy-D-glucopyranose using p-nitrophenyl-alpha-L-fucopyranose as the donor and 2-acetamido-2-deoxy-D-glucopyranose as the acceptor. The chemical identity of the product obtained was demonstrated by HPLC, ion spray mass spectrometry and NMR spectroscopy. Further transglycosylation using a beta-galactosidase (E.C. 3.2.1.23) yielded the branched oligosaccharide 2-acetamido-2-deoxy-3-O-(alpha-L-fucopyranosyl)-4-O-(beta-D-galactopyran osyl)-D-glucopyranose, i.e., the Lewis(x) antigen.
authors.affiliation: Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Italy. vetere@univ.trieste.it
authors.forename: A
authors.initials: A
authors.lastname: Vetere
authors.forename: C
authors.initials: C
authors.lastname: Galateo
authors.forename: S
authors.initials: S
authors.lastname: Paoletti
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D004187:Disaccharides / Q000096:biosynthesis* / Q000737:chemistry; D006031:Glycosylation; D016256:Lewis X Antigen / Q000096:biosynthesis / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009844:Oligosaccharides / Q000096:biosynthesis*; D014867:Water; D005644:alpha-L-Fucosidase / Q000378:metabolism
chemical_list: D004187:Disaccharides; D016256:Lewis X Antigen; D009844:Oligosaccharides; D014867:Water; C106531:3-O-fucopyranosyl-2-acetamido-2-deoxyglucopyranose; D005644:alpha-L-Fucosidase