title: Microwave-Assisted Synthesis of Glycoconjugates by Transgalactosylation with Recombinant Thermostable β-Glycosidase from Pyrococcus.
abstract: The potential of the hyperthermophilic β-glycosidase from Pyrococcus woesei (DSM 3773) for the synthesis of glycosides under microwave irradiation (MWI) at low temperatures was investigated. Transgalactosylation reactions with β-N-acetyl-d-glucosamine as acceptor substrate (GlcNAc-linker-tBoc) under thermal heating (TH, 85 °C) and under MWI at 100 and 300 W resulted in the formation of (Galβ(1,4)GlcNAc-linker-tBoc) as the main product in all reactions. Most importantly, MWI at temperatures far below the temperature optimum of the hyperthermophilic glycosidase led to higher product yields with only minor amounts of side products β(1,6-linked disaccharide and trisaccharides). At high acceptor concentrations (50 mM), transgalactosylation reactions under MWI at 300 W gave similar product yields when compared to TH at 85 °C. In summary, we demonstrate that MWI is useful as a novel experimental set-up for the synthesis of defined galacto-oligosaccharides. In conclusion, glycosylation reactions under MWI at low temperatures have the potential as a general strategy for regioselective glycosylation reactions of hyperthermophilic glycosidases using heat-labile acceptor or donor substrates.
authors: Laboratory for Biomaterials, Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, 52074 Aachen, Germany. m.henze@biotec.rwth-aachen.de.
authors: Manja
authors: M
authors: Henze
authors: Laboratory for Biomaterials, Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, 52074 Aachen, Germany. d.merker@biotec.rwth-aachen.de.
authors: Dorothee
authors: D
authors: Merker
authors: Laboratory for Biomaterials, Institute of Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, 52074 Aachen, Germany. l.elling@biotec.rwth-aachen.de.
authors: Lothar
authors: L
authors: Elling
mesh_terms: D002384:Catalysis; D004795:Enzyme Stability; D006001:Glycoconjugates / Q000138:chemical synthesis* / Q000737:chemistry; D006026:Glycoside Hydrolases / Q000737:chemistry*; D006031:Glycosylation; D006358:Hot Temperature; D006868:Hydrolysis; D008872:Microwaves; D008970:Molecular Weight; D019711:Pyrococcus / Q000201:enzymology*; D011994:Recombinant Proteins
chemical_list: D006001:Glycoconjugates; D011994:Recombinant Proteins; D006026:Glycoside Hydrolases
keywords: Pyrococcus; biocatalysis; carbohydrates; glycoconjugates; glycosidase; microwave irradiation; transgalactosylation