title: Converting bulk sugars into prebiotics: semi-rational design of a transglucosylase with controlled selectivity.
abstract: Despite the growing importance of prebiotics in nutrition and gastroenterology, their structural variety is currently still very limited. The lack of straightforward procedures to gain new products in sufficient amounts often hampers application testing and further development. Although the enzyme sucrose phosphorylase can be used to produce the rare disaccharide kojibiose (α-1,2-glucobiose) from the bulk sugars sucrose and glucose, the target compound is only a side product that is difficult to isolate. Accordingly, for this biocatalyst to become economically attractive, the formation of other glucobioses should be avoided and therefore we applied semi-rational mutagenesis and low-throughput screening, which resulted in a double mutant (L341I_Q345S) with a selectivity of 95% for kojibiose. That way, an efficient and scalable production process with a yield of 74% could be established, and with a simple yeast treatment and crystallization step over a hundred grams of highly pure kojibiose (>99.5%) was obtained.
authors: Centre for Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium. tom.desmet@ugent.be.
authors: Tom
authors: T
authors: Verhaeghe
authors: Centre for Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium. tom.desmet@ugent.be.
authors: Karel
authors: K
authors: De Winter
authors: Unité Fonctionnalité et Ingénierie des Protéines (UFIP), UMR CNRS 6286, Université de Nantes, 2, rue de la Houssinière, 44322 Nantes Cedex 3, France.
authors: Magali
authors: M
authors: Berland
authors: SynBioC Research Group, Department of Sustainable Organic Chemistry and Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors: Rob
authors: R
authors: De Vreese
authors: SynBioC Research Group, Department of Sustainable Organic Chemistry and Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
authors: Matthias
authors: M
authors: D'hooghe
authors: Unité Fonctionnalité et Ingénierie des Protéines (UFIP), UMR CNRS 6286, Université de Nantes, 2, rue de la Houssinière, 44322 Nantes Cedex 3, France.
authors: Bernard
authors: B
authors: Offmann
authors: Centre for Industrial Biotechnology and Biocatalysis, Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium. tom.desmet@ugent.be.
authors: Tom
authors: T
authors: Desmet
mesh_terms: D002241:Carbohydrates / Q000737:chemistry*; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D005964:Glucosyltransferases / Q000737:chemistry* / Q000378:metabolism; D015394:Molecular Structure; D056692:Prebiotics
chemical_list: D002241:Carbohydrates; D004187:Disaccharides; D056692:Prebiotics; C008237:kojibiose; D005964:Glucosyltransferases; C025901:sucrose phosphorylase