Beta-glucosidase, exo-beta-glucanase and pyridoxine transglucosylase activities of rice BGlu1

Biochem J. 2004 Apr 1;379(Pt 1):125-31. doi: 10.1042/BJ20031485.

Abstract

The bglu1 cDNA for a beta-glucosidase cloned from rice (Oryza sativa L.) seedlings was expressed as a soluble and active protein in Escherichia coli and designated BGlu1. This enzyme hydrolysed beta-1,4-linked oligosaccharides with increasing catalytic efficiency (kcat/Km) values as the DP (degree of polymerization) increased from 2 to 6. In contrast, hydrolysis of beta-1,3-linked oligosaccharides decreased from DP 2 to 3, and polymers with a DP greater than 3 were not hydrolysed. The enzyme also hydrolysed p -nitrophenyl beta-D-glycosides and some natural glucosides but with lower catalytic efficiency than beta-linked oligosaccharides. Pyridoxine 5'-O-beta-D-glucoside was the most efficiently hydrolysed natural glycoside tested. BGlu1 also had high transglucosylation activity towards pyridoxine, producing pyridoxine 5'-O-beta-D-glucopyranoside in the presence of the glucose donor p-nitrophenyl beta-D-glucoside.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Carbohydrate Conformation
  • Chromatography, High Pressure Liquid
  • DNA, Complementary / genetics
  • DNA, Plant / genetics
  • Glucan 1,4-beta-Glucosidase / genetics
  • Glucan 1,4-beta-Glucosidase / isolation & purification
  • Glucan 1,4-beta-Glucosidase / metabolism*
  • Glucosides / metabolism
  • Glucosyltransferases / genetics
  • Glucosyltransferases / isolation & purification
  • Glucosyltransferases / metabolism*
  • Glycosides / metabolism
  • Hordeum / enzymology
  • Hydrolysis
  • Kinetics
  • Molecular Sequence Data
  • Nuclear Magnetic Resonance, Biomolecular
  • Oligosaccharides / chemistry
  • Oligosaccharides / metabolism
  • Oryza / enzymology*
  • Oryza / genetics
  • Plant Proteins / genetics
  • Plant Proteins / isolation & purification
  • Plant Proteins / metabolism*
  • Pyridoxine / analogs & derivatives*
  • Pyridoxine / metabolism
  • Seedlings / enzymology
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Species Specificity
  • Substrate Specificity
  • beta-Glucosidase / genetics
  • beta-Glucosidase / isolation & purification
  • beta-Glucosidase / metabolism*

Substances

  • DNA, Complementary
  • DNA, Plant
  • Glucosides
  • Glycosides
  • Oligosaccharides
  • Plant Proteins
  • 4-nitrophenyl beta-D-glucoside
  • 5'-O-(glucopyranosyl)pyridoxine
  • Glucosyltransferases
  • beta-Glucosidase
  • Glucan 1,4-beta-Glucosidase
  • Pyridoxine

Associated data

  • GENBANK/U28047