title: alpha-Mannosidase-catalyzed synthesis of a (1-->2)-alpha-D-rhamnodisaccharide derivative.
abstract: Enzymatic transglycosylation using p-nitrophenyl alpha-D-rhamnopyranoside as the glycosyl donor and 6equiv of ethyl 1-thio-alpha-D-rhamnopyranoside as the glycosyl acceptor yielded a D-rhamnooligosaccharide derivative. The reaction was catalyzed by jack bean alpha-mannosidase in a 1:1 (v/v) mixture of 0.1 M sodium citrate buffer (pH4.5)-MeCN at 25 degrees C. The enzyme exhibited high catalytic activity for the reaction, to afford in 32.1% isolated yield (based on donor substrate) ethyl alpha-D-rhamnopyranosyl-(1-->2)-1-thio-alpha-D-rhamnopyranoside, which is a derivative of the common oligosaccharide unit of the antigenic lipopolysaccharides from Pseudomonas.
authors.affiliation: Laboratory of Bio-organic Chemistry, College of Bioresource Sciences, Nihon University, 1866 Kameino, Fujisawa-shi, Kanagawa 252-8510, Japan. nishio@brs.nihon-u.ac.jp
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nishio
authors.forename: Shigeki
authors.initials: S
authors.lastname: Hoshino
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kondo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ogawa
authors.forename: Yukari
authors.initials: Y
authors.lastname: Matsuishi
authors.forename: Mai
authors.initials: M
authors.lastname: Kitagawa
authors.forename: Ryu
authors.initials: R
authors.lastname: Kawachi
authors.forename: Tadatake
authors.initials: T
authors.lastname: Oku
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004187:Disaccharides / Q000096:biosynthesis* / Q000737:chemistry*; D006031:Glycosylation; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D043323:alpha-Mannosidase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004187:Disaccharides; C494284:ethyl rhamnopyranosyl-(1-2)-1-thiorhamnopyranoside; D043323:alpha-Mannosidase