title: Transglycosylation specificity of Acremonium sp. α-rhamnosyl-β-glucosidase and its application to the synthesis of the new fluorogenic substrate 4-methylumbelliferyl-rutinoside.
abstract: Transglycosylation potential of the fungal diglycosidase α-rhamnosyl-β-glucosidase was explored. The biocatalyst was shown to have broad acceptor specificity toward aliphatic and aromatic alcohols. This feature allowed the synthesis of the diglycoconjugated fluorogenic substrate 4-methylumbelliferyl-rutinoside. The synthesis was performed in one step from the corresponding aglycone, 4-methylumbelliferone, and hesperidin as rutinose donor. 4-Methylumbelliferyl-rutinoside was produced in an agitated reactor using the immobilized biocatalyst with a 16% yield regarding the sugar acceptor. The compound was purified by solvent extraction and silica gel chromatography. MALDI-TOF/TOF data recorded for the [M+Na](+) ions correlated with the theoretical monoisotopic mass (calcd [M+Na](+): 507.44 m/z; obs. [M+Na](+): 507.465 m/z). 4-Methylumbelliferyl-rutinoside differs from 4-methylumbelliferyl-glucoside in the rhamnosyl substitution at the C-6 of glucose, and this property brings about the possibility to explore in nature the occurrence of endo-β-glucosidases by zymographic analysis.
authors.affiliation: INCITAP-CONICET, Departamento de Química, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Av. Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Mazzaferro
authors.forename: Lucrecia
authors.initials: L
authors.lastname: Piñuel
authors.forename: Rosa
authors.initials: R
authors.lastname: Erra-Balsells
authors.forename: Silvana L
authors.initials: SL
authors.lastname: Giudicessi
authors.forename: Javier D
authors.initials: JD
authors.lastname: Breccia
mesh_terms: D000164:Acremonium / Q000201:enzymology*; D004187:Disaccharides / Q000138:chemical synthesis* / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry*; D005959:Glucosidases / Q000378:metabolism*; D006027:Glycosides / Q000138:chemical synthesis* / Q000737:chemistry*; D006031:Glycosylation; D006923:Hymecromone / Q000138:chemical synthesis / Q000737:chemistry / Q000031:analogs & derivatives; D012995:Solubility; D012997:Solvents / Q000737:chemistry; D013379:Substrate Specificity; D014867:Water / Q000737:chemistry
chemical_list: C571836:4-methylumbelliferyl-rutinoside; D004187:Disaccharides; D005456:Fluorescent Dyes; D006027:Glycosides; D012997:Solvents; D014867:Water; D006923:Hymecromone; D005959:Glucosidases