title: Lactose- and cellobiose-derived branched trisaccharides and a sucrose-containing trisaccharide produced by acceptor reactions of Weissella confusa dextransucrase.
abstract: Dextran-producing Weissella have received significant attention. However, except for maltose, the acceptor reactions of Weissella dextransucrases with different sugars have not been investigated. The action of recombinant Weissella confusa VTT E-90392 dextransucrase was tested with several potential acceptors, particularly, analogs lactose and cellobiose. The major acceptor products of both disaccharides were identified as branched trisaccharides, with a glucosyl residue α-(1 → 2)-linked to the acceptor's reducing end. An additional product, isomelezitose (6(Fru)-α-Glcp-sucrose), was also produced when using lactose as an acceptor. This is the first report of the synthesis of isomelezitose by a dextransucrase. The NMR spectra of the three trisaccharides were fully assigned, and their structures were confirmed by selective enzymatic hydrolysis. The trisaccharides prepared from (13)C6(glc) sucrose and lactose were analyzed by ESI-MS(n), and the fragmentation patterns of these compounds were characterized.
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland. Electronic address: qiao.shi@helsinki.fi.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Shi
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland.
authors.forename: Minna
authors.initials: M
authors.lastname: Juvonen
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland.
authors.forename: Yaxi
authors.initials: Y
authors.lastname: Hou
authors.affiliation: VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Finland.
authors.forename: Ilkka
authors.initials: I
authors.lastname: Kajala
authors.affiliation: VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Nyyssölä
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland.
authors.forename: Ndegwa Henry
authors.initials: NH
authors.lastname: Maina
authors.affiliation: VTT Technical Research Centre of Finland, P.O. Box 1000, FI-02044 VTT, Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Maaheimo
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland.
authors.forename: Liisa
authors.initials: L
authors.lastname: Virkki
authors.affiliation: Department of Food and Environmental Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland.
authors.forename: Maija
authors.initials: M
authors.lastname: Tenkanen
mesh_terms: D002475:Cellobiose / Q000737:chemistry*; D003911:Dextrans / Q000737:chemistry; D005964:Glucosyltransferases / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008958:Models, Molecular; D013395:Sucrose / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014312:Trisaccharides / Q000737:chemistry*; D058836:Weissella / Q000737:chemistry*
chemical_list: D003911:Dextrans; D014312:Trisaccharides; D002475:Cellobiose; D013395:Sucrose; D005964:Glucosyltransferases; C020025:dextransucrase
keywords: Dextransucrase; Isomelezitose; NMR; Oligosaccharide; Tandem mass spectrometry; Weissella; α-(1→2)-Linkage