title: Identification of Bacillus selenitireducens MLS10 maltose phosphorylase possessing synthetic ability for branched α-D-glucosyl trisaccharides.
abstract: We discovered an inverting maltose phosphorylase (Bsel2056) belonging to glycoside hydrolase family 65 from Bacillus selenitireducens MLS10, which possesses synthetic ability for α-D-glucosyl disaccharides and trisaccharides through the reverse phosphorolysis with β-D-glucose 1-phosphate as the donor. Bsel2056 showed the flexibility for monosaccharide acceptors with alternative C2 substituent (2-amino-2-deoxy-D-glucose, 2-deoxy-D-arabino-hexose, 2-acetamido-2-deoxy-D-glucose, D-mannose), resulting in production of 1,4-α-D-glucosyl disaccharides with strict regioselectivity. In addition, Bsel2056 synthesized two maltose derivatives possessing additional D-glucosyl residue bound to C2 position of the D-glucose residue at the reducing end, 1,4-α-D-glucopyranosyl-[1,2-α-D-glucopyranosyl]-D-glucose and 1,4-α-D-glucopyranosyl-[1,2-β-D-glucopyranosyl]-D-glucose, from 1,2-α-D-glucopyranosyl-D-glucose (kojibiose) and 1,2-β-D-glucopyranosyl-D-glucose (sophorose), respectively, as the acceptors. These results suggested that Bsel2056 possessed a binding space to accommodate the bulky C2 substituent of D-glucose.
authors.affiliation: Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Nihira
authors.forename: Yuka
authors.initials: Y
authors.lastname: Saito
authors.forename: Motomitsu
authors.initials: M
authors.lastname: Kitaoka
authors.forename: Ken'ichi
authors.initials: K
authors.lastname: Otsubo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakai
mesh_terms: D001407:Bacillus / Q000201:enzymology*; D055162:Biocatalysis; D002236:Carbohydrate Conformation; D003001:Cloning, Molecular; D004187:Disaccharides / Q000096:biosynthesis / Q000737:chemistry; D005964:Glucosyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008320:Maltose / Q000031:analogs & derivatives / Q000096:biosynthesis / Q000737:chemistry; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature; D014312:Trisaccharides / Q000096:biosynthesis* / Q000737:chemistry*
chemical_list: D004187:Disaccharides; D011994:Recombinant Proteins; D014312:Trisaccharides; D008320:Maltose; D005964:Glucosyltransferases; C021535:maltose phosphorylase