Extracellular monoenzyme deglycosylation system of 7-O-linked flavonoid beta-rutinosides and its disaccharide transglycosylation activity from Stilbella fimetaria

Arch Microbiol. 2010 May;192(5):383-93. doi: 10.1007/s00203-010-0567-7. Epub 2010 Apr 1.


We screened for microorganisms able to use flavonoids as a carbon source; and one isolate, nominated Stilbella fimetaria SES201, was found to possess a disaccharide-specific hydrolase. It was a cell-bound ectoenzyme that was released to the medium during conidiogenesis. The enzyme was shown to cleave the flavonoid hesperidin (hesperetin 7-O-alpha-rhamnopyranosyl-beta-glucopyranoside) into rutinose (alpha-rhamnopyranosyl-beta-glucopyranose) and hesperetin. Since only intracellular traces of monoglycosidase activities (beta-glucosidase, alpha-rhamnosidase) were produced, the disaccharidase alpha-rhamnosyl-beta-glucosidase was the main system utilized by the microorganism for hesperidin hydrolysis. The enzyme was a glycoprotein with a molecular weight of 42224 Da and isoelectric point of 5.7. Even when maximum activity was found at 70 degrees C, it was active at temperatures as low as 5 degrees C, consistent with the psychrotolerant character of S. fimetaria. Substrate preference studies indicated that the enzyme exhibits high specificity toward 7-O-linked flavonoid beta-rutinosides. It did not act on flavonoid 3-O-beta-rutinoside and 7-O-beta-neohesperidosides, neither monoglycosylated substrates. In an aqueous medium, the alpha-rhamnosyl-beta-glucosidase was also able to transfer rutinose to other acceptors besides water, indicating its potential as biocatalyst for organic synthesis. The monoenzyme strategy of Acremonium sp. SES201 = DSM 24697, [corrected] as well as the enzyme substrate preference for 7-O-beta-flavonoid rutinosides, is unique characteristics among the microbial flavonoid deglycosylation systems reported.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA, Ribosomal / chemistry
  • DNA, Ribosomal / genetics
  • Disaccharides / metabolism*
  • Enzyme Stability
  • Fungal Proteins / chemistry
  • Fungal Proteins / isolation & purification
  • Fungal Proteins / metabolism
  • Genes, rRNA
  • Glucosidases / chemistry
  • Glucosidases / isolation & purification
  • Glucosidases / metabolism
  • Hesperidin / metabolism*
  • Hypocreales / classification
  • Hypocreales / enzymology*
  • Hypocreales / growth & development
  • Hypocreales / metabolism*
  • Isoelectric Point
  • Molecular Sequence Data
  • Molecular Weight
  • RNA, Fungal / genetics
  • RNA, Ribosomal, 18S / genetics
  • Sequence Analysis, DNA
  • Substrate Specificity
  • Temperature


  • DNA, Fungal
  • DNA, Ribosomal
  • Disaccharides
  • Fungal Proteins
  • RNA, Fungal
  • RNA, Ribosomal, 18S
  • rutinose
  • Hesperidin
  • Glucosidases
  • hesperetin

Associated data

  • GENBANK/FJ939394
  • GENBANK/FJ939395