Overexpression of D-psicose 3-epimerase from Ruminococcus sp. in Escherichia coli and its potential application in D-psicose production

Biotechnol Lett. 2012 Oct;34(10):1901-6. doi: 10.1007/s10529-012-0986-4. Epub 2012 Jul 4.

Abstract

The D-psicose 3-epimerase (DPE) gene from Ruminococcus sp. was cloned and overexpressed in Escherichia coli. The recombinant protein was purified and characterized. It was optimally active at pH 7.5-8.0 and 60 °C. Activity was not dependent on the presence of metal ions; however, it became more thermostable with added Mn(2+). The K (m) of the enzyme for D-psicose (48 mM) was lower than that for D-tagatose (230 mM), suggesting that D-psicose is the optimum substrate. More importantly, the thermostability of the novel DPE from Ruminococcus is the strongest among all of the D-psicose and D-tagatose 3-epimerases and may be suitable for the industrial production of D-psicose from fructose.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / biosynthesis*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Carbohydrate Epimerases / biosynthesis*
  • Carbohydrate Epimerases / chemistry
  • Carbohydrate Epimerases / genetics
  • Carbohydrate Epimerases / metabolism
  • Cloning, Molecular
  • Enzyme Stability
  • Escherichia coli / enzymology
  • Escherichia coli / genetics*
  • Fructose / metabolism*
  • Hydrogen-Ion Concentration
  • Metals
  • Recombinant Proteins / biosynthesis*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Ruminococcus / enzymology*
  • Ruminococcus / genetics
  • Substrate Specificity
  • Temperature

Substances

  • Bacterial Proteins
  • Metals
  • Recombinant Proteins
  • psicose
  • Fructose
  • Carbohydrate Epimerases