Enzymic synthesis of di- and tri-saccharide glycosides, using glycosidases and beta-D-galactoside 3-alpha-sialyl-transferase.
The following disaccharide glycosides were obtained in yields of 10-35% from the appropriate donor and acceptor glycosides by employing glycosidases as catalysts: alpha-D-Galp-(1----3)-alpha-D-GalpNAc-OEt (alpha-D-galactosidase), beta-D-Galp-(1----3)-alpha-D-GalpNAc-OEt and beta-D-Galp-(1----3)-beta-D-GalpNAc-OEtBr (beta-D-galactosidase), beta-D-GlcpNAc-(1----6)-beta-D-Galp-OMe and beta-D-GlcpNAc-(1----6)-alpha-D-Manp-OMe (beta-N-acetylglucosaminidase). With beta-D-GlcpNAc-OEtSiMe3 as the acceptor, beta-D-galactosidase gave beta-D-Galp-(1----3)-beta-D-GlcpNAc-OEtSiMe3 almost exclusively, whereas, with beta-D-GlcpNAc-OMe as the acceptor, beta-D-Galp-(1----3)-beta-D-GlcpNAc-OMe was formed in only slightly excess over teh analogous beta-(1----4)-linked glycoside. The use of beta-D-galactosidase and beta-D-galactoside 3-alpha-sialyltransferase in sequence provided a convenient route to the trisaccharide glycosides alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-alpha-D-GalpNAc-OEt, alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-beta-D-GalpNAc-OE tBr, and alpha-D-Neup5Ac-(2----3)-beta-D-Galp-(1----3)-beta-D-GlcpNAc-OMe.
Nilsson
K G
KG
Carbohydrates International, Arlöv, Sweden.
D000118:Acetylglucosaminidase / Q000378:metabolism; D000818:Animals; D004187:Disaccharides / Q000138:chemical synthesis*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D009904:Optical Rotation; D012799:Sialyltransferases / Q000378:metabolism*; D013363:Submandibular Gland / Q000201:enzymology; D013379:Substrate Specificity; D013552:Swine; D014312:Trisaccharides / Q000138:chemical synthesis*; D000519:alpha-Galactosidase / Q000378:metabolism; D001616:beta-Galactosidase / Q000378:metabolism; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
D004187:Disaccharides; D007202:Indicators and Reagents; D014312:Trisaccharides; D012799:Sialyltransferases; D006026:Glycoside Hydrolases; D000519:alpha-Galactosidase; D001616:beta-Galactosidase; D000118:Acetylglucosaminidase; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase