Chemoenzymatic synthesis of Galα1-3Gal, Galα1-3Galβ1-4GlcNAc and their PEG-conjugates.
摘要:
Gal alpha 1-3Gal-pNP was prepared enzymatically from Gal-pNP using alpha-galactosidase from coffee beans. PEG was attached after the reduction of nitro group into amino group to give Gal alpha 1-3Gal-PEG conjugate. After removing the pNP group in Gal alpha 1-3Gal-pNP, the obtained disaccharide was used for the synthesis of Gal alpha 1-3Gal beta 1-4GlcNAc and corresponding trisaccharide-PEG conjugate. (C) 1997, Elsevier Science Ltd.
α-Galactobiosyl units: thermodynamics and kinetics of their formation by transglycosylations catalysed by the GH36 α-galactosidase from Thermotoga maritima
作者:Anna S. Borisova、Dina R. Ivanen、Kirill S. Bobrov、Elena V. Eneyskaya、Georgy N. Rychkov、Mats Sandgren、Anna A. Kulminskaya、Michael L. Sinnott、Konstantin A. Shabalin
DOI:10.1016/j.carres.2014.11.003
日期:2015.1
a limiting factor for application of the enzyme in the directed synthesis of oligogalactosides. However, this property can be used as a convenient tool in studies of thermodynamics of a glycosidic bond. Here, a novel approach to energy difference estimation is suggested. Both transglycosylation and hydrolysis of three types of galactosidic linkages were investigated using total kinetics of formation
We show that the yields in saccharide synthesis by tranglycosylation with alpha-galactosidase from green coffee beans can be greatly enhanced when working in ice. Thus, methyl alpha-D-galactopyranosyl-(1-->3)-alpha-D-galactopyranoside (3a) produced by reaction of alpha-D-galactopyranosyl fluoride 1 with methyl alpha-D-galactopyranoside (2) is obtained with 51% yield in ice while only 29% is synthesized at 37 degreesC. This result, already previously found by others with proteases and by us with a P-galactosidase appears to be a general property of hydrolases. (C) 2002 Elsevier Science Ltd. All rights reserved.
Chemoenzymatic synthesis of Galα1-3Gal, Galα1-3Galβ1-4GlcNAc and their PEG-conjugates.
Gal alpha 1-3Gal-pNP was prepared enzymatically from Gal-pNP using alpha-galactosidase from coffee beans. PEG was attached after the reduction of nitro group into amino group to give Gal alpha 1-3Gal-PEG conjugate. After removing the pNP group in Gal alpha 1-3Gal-pNP, the obtained disaccharide was used for the synthesis of Gal alpha 1-3Gal beta 1-4GlcNAc and corresponding trisaccharide-PEG conjugate. (C) 1997, Elsevier Science Ltd.