title: A novel two-step enzymatic synthesis of blastose, a β-d-fructofuranosyl-(2↔6)-d-glucopyranose sucrose analogue.
abstract: Blastose, a natural disaccharide found in honey, is usually found as a byproduct of fructo-oligosaccharide synthesis from sucrose with fructosyltransferases. In this study, we describe a novel two-step biosynthetic route to obtain blastose, designed from a detailed observation of B. subtilis levansucrase (SacB) acceptor structural requirements for fructosylation. The strategy consisted first in the synthesis of the trisaccharide O-β-d-Fruf-(2↔6)-O-α-d-Glcp-(1↔1)-α-d-Glcp, through a regioselective β-d-transfructosylation of trehalose (Tre) which acts as acceptor in a reaction catalyzed by SacB using sucrose or levan as fructosyl donor. In this reaction, levansucrase (LS) transfers regioselectively a fructosyl residue to either C6-OH group of the glucose residues in Tre. The resulting trisaccharide obtained in 23% molar yield based on trehalose, was purified and fully characterized by extensive NMR studies. In the second step, the trisaccharide is specifically hydrolyzed by trehalase, to obtain blastose in 43.2% molar yield based on the trisaccharide. This is the first report describing the formation of blastose through a sequential transfuctosylation-hydrolysis reaction.
authors.affiliation: Departamento Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, C.P. 62209 Cuernavaca-Mor., Mexico.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Miranda-Molina
authors.affiliation: Departamento Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, C.P. 62209 Cuernavaca-Mor., Mexico.
authors.forename: Edmundo
authors.initials: E
authors.lastname: Castillo
authors.affiliation: Departamento Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, C.P. 62209 Cuernavaca-Mor., Mexico. Electronic address: agustin@ibt.unam.mx.
authors.forename: Agustin
authors.initials: A
authors.lastname: Lopez Munguia
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology; D001426:Bacterial Proteins / Q000378:metabolism; D004186:Disaccharidases / Q000378:metabolism*; D005630:Fructans / Q000378:metabolism; D006602:Hexosyltransferases / Q000378:metabolism*; D006868:Hydrolysis; D013395:Sucrose / Q000378:metabolism; D014199:Trehalose / Q000378:metabolism*; D014312:Trisaccharides / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D005630:Fructans; D014312:Trisaccharides; C000618994:blastose; D013395:Sucrose; C072599:levan; D014199:Trehalose; D006602:Hexosyltransferases; C021513:levansucrase; D004186:Disaccharidases
keywords: Blastose; Erlose (PubChem CID: 193471); Lactosucrose (PubChem CID: 174626); Levan (PubChem CID: 440946); Levanobiose (PubChem CID: 439555); Levansucrase; Neokestose (PubChem CID: 107452); Prebiotics; Regioselectivity; Sucrose (PubChem CID: 5988); Trehalase; Trehalose; Trehalose (PubChem CID: 7427); d-Fructose (PubChem CID: 5984); d-Galactose (PubChem CID: 6036); d-Glucose (PubChem CID:5793); dl-Xylose (PubChem CID: 644160)