Transglycosylation specificity of Acremonium sp. alpha-rhamnosyl-beta-glucosidase and its application to the synthesis of the new fluorogenic substrate 4-methylumbelliferyl-rutinoside

LAURA S. MAZZAFERRO; LUCRECIA PIÑUEL; ROSA ERRA-BALSELLS; SILVANA GIUDICESSI; JAVIER D. BRECCIA

CARBOHYDRATE RESEARCH

ELSEVIER SCI LTD

Año: 2012 vol. 347 p. 69 - 75

0008-6215

Transglycosylation potential of the fungal diglycosidase a-rhamnosyl-b-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-ruti- noside. The synthesis was performed in one step from the corresponding aglycone, 4-methylumbellifer- one, 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-b-glucosidases by zymographic analysis.