Cloning, expression and characterization of an alkaline thermostable GH9 endoglucanase from Thermobifida halotolerans YIM 90462 T

Bioresour Technol. 2011 Nov;102(21):10143-6. doi: 10.1016/j.biortech.2011.08.019. Epub 2011 Aug 10.

Abstract

The endoglucanase gene, thcel9A, from Thermobifida halotolerans YIM 90462(T) was cloned and expressed in Escherichia coli BL 21(DE). The 2895-bp full-length gene encodes a 964-residue polypeptide (Thcel9A) containing a catalytic domain belonging to glycosyl hydrolases (GH) family 9. Phylogenetic analysis indicated that Thcel9A is closely related to Cel9A of Thermobifidafusca YX. Thcel9A was purified from the culture supernatant by Ni(2+)-affinity chromatography and the purified enzyme exhibited optimal activity at 55°C and pH 8.0. Substrate specificity assays showed that it not only had CMCase activity, but also hydrolase activity on microcrystalline cellulose and filter paper. These properties suggested that Thcel9A is a classical GH9 group A endoglucanase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinomycetales / drug effects
  • Actinomycetales / enzymology*
  • Actinomycetales / genetics*
  • Alkalies / pharmacology*
  • Cellulase / chemistry
  • Cellulase / genetics*
  • Cellulase / isolation & purification
  • Cellulase / metabolism*
  • Cloning, Molecular
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Stability / drug effects
  • Hydrogen-Ion Concentration / drug effects
  • Kinetics
  • Molecular Sequence Data
  • Protein Structure, Tertiary
  • Recombinant Proteins / metabolism
  • Substrate Specificity / drug effects
  • Temperature

Substances

  • Alkalies
  • Recombinant Proteins
  • Cellulase

Associated data

  • GENBANK/JF826789