209977-51-5Relevant articles and documents
ENZYMIC SYNTHESIS OF DISACCHARIDES BY USE OF THE REVERSED HYDROLYSIS ACTIVITY OF β-D-GALACTOSIDASES
Ajisaka, Katsumi,Fujimoto, Hiroshi,Nishida, Hiroko
, p. 35 - 42 (1988)
D-Galactosyl disaccharides have been synthesized by utilizing the reversed hydrolysis activity of β-D-galactosidases from E. coli and from A. oryzae, respectively.In order to shift the equilibrium towards the formation of disaccharide, solutions of monosaccharides were circulated through columns of immobilized β-D-galactosidase and activated carbon in series.After 24 h, the disaccharides were eluted with aqueous 50 percent ethanol from the column of activated carbon and analyzed by h.p.l.c. and 13C-n.m.r. spectroscopy.In this way, β-D-galactosyl-D-glucose, β-D-galactosyl-2-acetamido-2-deoxy-D-glucose, and β-D-galactosyl-D-fructose were produced in yields of 6.0, 16.0, and 11.3 percent, respectively, when the immobilized β-D-galactosidase from E. coli was used.The possible mechanism of the synthesis of the disaccharides is discussed.
The Heyns rearrangement revisited: An exceptionally simple two-step chemical synthesis of D-lactosamine from lactulose
Wrodnigg, Tanja M.,Stuetz, Arnold E.
, p. 827 - 828 (1999)
Disaccharides containing D-glucosamine at the reducing end can be conveniently synthesized in good yields from O-glycosylated D-fructoses by the title reaction [Eq. (a)]. With all the disaccharides investigated, the method proceeded-presumably because of
Optimised N-acetyl-D-lactosamine synthesis using Thermus thermophilus β-galactosidase in bio-solvents
Sandoval, Manuel,Civera, Concepción,Berenguer, José,García-Blanco, Francisco,Hernaiz, María J.
, p. 1148 - 1152 (2013/02/25)
Synthesis of N-acetyl-D-lactosamine (Gal-β[1→4]GlcNAc, LacNAc) catalyzed by β-galactosidase from Thermus thermophilus (TTP0042) is affected by side reactions that give as result very low yields (about 20%) of LAcNAc when the reaction is performed in buffer. The process is improved (up to 91% of disaccharide yield) when the reaction takes place in the presence of solvents from biomass (bio-solvents) at 2.0 M concentration. Most of the solvents tested increased the LacNAc synthesis and reduced the undesired side reactions. In order to understand the possible effects of these solvents over the enzyme regioselectivity, we developed a conformational study of the enzyme structure in the presence of a selected bio-solvent by circular dichroism and fluorescence. According to this study, we were able to conclude that the presence of bio-solvents in the reaction media modifies the enzyme secondary and tertiary structure and this may be the cause of the regioselectivity changes observed in the transglycosylation reaction.
Solvents derived from glycerol modify classical regioselectivity in the enzymatic synthesis of disaccharides with Biolacta β-galactosidase
Perez-Sanchez, Maria,Sandoval, Manuel,Cortes-Cabrera, Alvaro,Garcia-Marin, Hector,Sinisterra, Jose V.,Garcia, Jose I.,Hernaiz, Maria J.
experimental part, p. 2810 - 2817 (2011/12/05)
Green solvents made from glycerol change the classical regioselectivity of Biolacta No 5 β-galactosidase, from β(1→4) to β(1→6) linkages when a 2 M concentration was used. In order to explain these results, the non-proteic compounds present in
