Thermostable Lichenase from Clostridium thermocellum as a Host Protein in the Domain Insertion Approach

Biochemistry (Mosc). 2019 Aug;84(8):931-940. doi: 10.1134/S0006297919080091.


Clostridium thermocellum lichenase (endo-β-1,3;1,4-glucan-D-glycosyl hydrolase, EC (P29716)) has been tested for the insertion of two model fluorescent proteins (EGFP and TagRFP) into two regions of this enzyme. Functional folding of the resulting proteins was confirmed by retention of lichenase activity and EGFP and TagRFP fluorescence. These results convincingly demonstrate that (i) the two experimentally selected lichenase loop regions may serve as the areas for domain insertion without disturbing enzyme folding in vivo; (ii) lichenase permits not only single but also tandem insertions of large protein domains. High specific activity, outstanding thermostability, and efficient in vitro refolding of thermostable lichenase make it an attractive new host protein for the insertional fusion of domains in the engineering of multifunctional proteins.

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Cloning, Molecular
  • Clostridium thermocellum / enzymology*
  • DNA Transposable Elements
  • Escherichia coli / cytology
  • Fluorescence
  • Glycoside Hydrolases / chemistry*
  • Glycoside Hydrolases / genetics*
  • Green Fluorescent Proteins / chemistry
  • Green Fluorescent Proteins / genetics
  • Luminescent Proteins / chemistry
  • Luminescent Proteins / genetics
  • Microscopy, Fluorescence
  • Protein Domains*
  • Protein Engineering*
  • Protein Refolding
  • Recombinant Fusion Proteins
  • Red Fluorescent Protein
  • Temperature


  • Bacterial Proteins
  • DNA Transposable Elements
  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins
  • Glycoside Hydrolases
  • licheninase