Structural analyses of new tri- and tetrasaccharides produced from disaccharides by transglycosylation of purified Trichoderma viride beta-glucosidase.
A new beta-glucosidase was partially purified from Trichoderma viride cellulase. This beta-glucosidase catalyzed a transglycosylation reaction of cellobiose to give beta-D-Glc-(1-->6)-beta-D-Glc-(1-->4)-D-Glc (1, yield: 18.8%) and beta-D-Glc-(1-->6)-beta-D-Glc-(1-->6)-beta-D-Glc-(1-->4)-D-Glc (2, 3.7%), regioselectively. Furthermore, the enzyme regioselectively converted laminaribiose and gentiobiose into beta-D-Glc-(1-->6)-beta-D-Glc-(1-->3)-D-Glc (3, 15.3%) and beta-D-Glc-(1-->6)-beta-D-Glc-(1-->6)-D-Glc (4, 20.2%), respectively. The structures (1-4) of the products were determined by 1H and 13C NMR spectroscopies. This high regio- and stereoselectively of the beta-glucosidase could be applied for oligosaccharide synthesis.
Kono
H
H
Division of Molecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo, Japan. kohno@dove-mc.eng.hokudai.ac.jp
Kawano
S
S
Tajima
K
K
Erata
T
T
Takai
M
M
D002240:Carbohydrate Sequence; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry*; D013379:Substrate Specificity; D013696:Temperature; D014242:Trichoderma / Q000201:enzymology*; D001617:beta-Glucosidase / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism
D009844:Oligosaccharides; D001617:beta-Glucosidase