Novel thermostable endo-xylanase cloned and expressed from bacterium Geobacillus sp. WSUCF1

Bioresour Technol. 2014 Aug:165:314-8. doi: 10.1016/j.biortech.2014.03.112. Epub 2014 Mar 31.

Abstract

A gene encoding a GH10 endo-xylanase from Geobacillus sp. WSUCF1 was cloned and expressed in Escherichia coli. Recombinant endo-xylanase (37kDa) exhibited high specific activity of 461.0U/mg of protein. Endo-xylanase was optimally active on birchwood xylan at 70°C and pH 6.5. The endo-xylanase was found to be highly thermostable at 50 and 60°C, retaining 82% and 50% of its original activity, respectively, after 60h. High xylan conversions (92%) were obtained with oat-spelt xylan hydrolysis. Higher glucan and xylan conversions were obtained on AFEX-treated corn stover with an enzyme cocktail containing WSUCF1 endo-xylanase (71% and 47%) as compared to enzyme cocktail containing commercial fungal endo-xylanase (64% and 41%). High specific activity, active at high pH's, wide substrate specificity, and higher hydrolytic activity on recalcitrant lignocellulose, make this endo-xylanase a suitable candidate for biofuel and bioprocess industries.

Keywords: AFEX-treated corn stover; Biofuels; Endo-xylanase; Thermostable.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Avena / metabolism
  • Base Sequence
  • Betula / metabolism
  • Cloning, Molecular
  • Electrophoresis, Polyacrylamide Gel
  • Endo-1,4-beta Xylanases / metabolism*
  • Enzyme Stability
  • Fungi / enzymology
  • Geobacillus / enzymology*
  • Hydrolysis
  • Lignin / metabolism
  • Phylogeny
  • Recombinant Proteins / metabolism
  • Temperature*
  • Xylans / metabolism

Substances

  • Recombinant Proteins
  • Xylans
  • lignocellulose
  • Lignin
  • Endo-1,4-beta Xylanases