Modification of linear (β1→3)-linked gluco-oligosaccharides with a novel recombinant β-glucosyltransferase (trans-β-glucosidase) enzyme from Bradyrhizobium diazoefficiens
| Autor: | Jakob K. Kristjansson, Jón Örvar G. Jónsson, Olafur H. Fridjonsson, Gerrit J. Gerwig, Hildegard Watzlawick, Josef Altenbuchner, Lubbert Dijkhuizen, Gudmundur O. Hreggvidsson, Arnthor Aevarsson, Justyna M. Dobruchowska, Johannis P. Kamerling |
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| Přispěvatelé: | Host-Microbe Interactions |
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
030106 microbiology Oligosaccharides Biochemistry 03 medical and health sciences chemistry.chemical_compound non-Leloir beta-glucosyltransferase Glycoside hydrolase Bradyrhizobium structural analysis Laminaribiose Bradyrhizobium diazoefficiens chemistry.chemical_classification Azotobacter biology oligosaccharide synthesis beta-Glucosidase Pseudomonas Oligosaccharide biology.organism_classification Recombinant Proteins 030104 developmental biology Enzyme chemistry biology.protein Biocatalysis Glucosyltransferase beta-D-glucans |
| Zdroj: | Glycobiology, 26(11), 1157-1170. Oxford University Press |
| ISSN: | 0959-6658 |
| Popis: | Recently, we have shown that glycoside hydrolases enzymes of family GH17 from proteobacteria (genera Pseudomonas, Azotobacter) catalyze elongation transfer reactions with laminari-oligosaccharides generating (β1→3) linkages preferably and to a lesser extent (β1→6) or (β1→4) linkages. In the present study, the cloning and characterization of the gene encoding the structurally very similar GH17 domain of the NdvB enzyme from Bradyrhizobium diazoefficiens, designated Glt20, as well as its catalytic properties are described. The Glt20 enzyme was strikingly different from the previously investigated bacterial GH17 enzymes, both regarding substrate specificity and product formation. The Azotobacter and Pseudomonas enzymes cleaved the donor laminari-oligosaccharide substrates three or four moieties from the non-reducing end, generating linear oligosaccharides. In contrast, the Glt20 enzyme cleaved donor laminari-oligosaccharide substrates two glucose moieties from the reducing end, releasing laminaribiose and transferring the remainder to laminari-oligosaccharide acceptor substrates creating only (β1→3)(β1→6) branching points. This enables Glt20 to transfer larger oligosaccharide chains than the other type of bacterial enzymes previously described, and helps explain the biologically significant formation of cyclic β-glucans in B. diazoefficiens. |
| Databáze: | OpenAIRE |
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