3-O-α-D-glucopyranosyl-L-rhamnose phosphorylase from Clostridium phytofermentans

Carbohydr Res. 2012 Mar 1;350:94-7. doi: 10.1016/j.carres.2011.12.019. Epub 2011 Dec 29.


We found an unreported activity of phosphorylase catalyzed by a protein (Cphy1019) belonging to glycoside hydrolase family 65 (GH65) from Clostridium phytofermentans. The recombinant Cphy1019 produced in Escherichia coli did not phosphorolyze α-linked glucobioses, such as trehalose (α1-α1), kojibiose (α1-2), nigerose (α1-3), and maltose (α1-4), which are typical substrates for GH65 enzymes. In reverse phosphorolysis, Cphy1019 utilized only l-rhamnose as the acceptor among various sugars examined with β-d-glucose 1-phosphate as the donor. The reaction product was determined to be 3-O-α-d-glucopyranosyl-l-rhamnose, indicating strict α1-3 regioselectivity. We propose 3-O-α-d-glucopyranosyl-l-rhamnose: phosphate β-d-glucosyltransferase as the systematic name and 3-O-α-d-glucopyranosyl-l-rhamnose phosphorylase as the short name for this novel GH65 phosphorylase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Clostridium / enzymology*
  • Disaccharides / chemistry
  • Disaccharides / metabolism*
  • Glucosyltransferases / chemistry
  • Glucosyltransferases / metabolism*
  • Hydrogen-Ion Concentration
  • Kinetics
  • Phosphorylases / genetics
  • Phosphorylases / isolation & purification
  • Phosphorylases / metabolism*
  • Stereoisomerism
  • Substrate Specificity
  • Temperature


  • Disaccharides
  • 3-O-alpha-D-glucopyranosyl-L-rhamnose phosphate beta-D-glucosyltransferase, Clostridium phytofermentans
  • Glucosyltransferases
  • Phosphorylases