The multidomain xylanase A of the hyperthermophilic bacterium Thermotoga neapolitana is extremely thermoresistant (original) (raw)

Abstract

The nucleotide sequence of the xynA gene, encoding extracellular xylanase A of Thermotoga neapolitana, was determined. The xynA gene was 3264 base pairs (bp) long and encoded a putative polypeptide of 1055 amino acids. Three different domains were identified by sequence comparison and functional analysis of proteins with N- and/or C-terminal deletions. The core domain displayed significant homology to members of the glycosyl hydrolase family 10. N- and C-terminal domains were dispensable for enzymatic activity and seemed to be responsible for thermostability and cellulose binding, respectively. The intact gene and its truncated variants were expressed in Escherichia coli and purified for biochemical characterization. The enzyme was shown to act as an endo-1,4-_β_-xylanase, but minor activities against lichenan, barley glucan, methylumbelliferyl cellobioside and _p_-nitrophenyl xyloside were also detected. The specific activity and pH and temperature optima for hydrolysis of oat xylan were 111.3 U·mg−1, 5.5 and 102°C, respectively. The endoxylanase was stable at 90°C and retained 50% activity when incubated for 2 h at 100°C.

Access this article

Log in via an institution

Subscribe and save

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

Download references

Author information

Authors and Affiliations

  1. Institut für Biologie, Humboldt Universität, Warschauer Str.43, D-10243, Berlin, Germany
    V. Zverlov, K. Piotukh & R. Borriss
  2. Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 46, 123182, Moscow, Russia
    V. Zverlov, O. Dakhova & G. Velikodvorskaya

Authors

  1. V. Zverlov
  2. K. Piotukh
  3. O. Dakhova
  4. G. Velikodvorskaya
  5. R. Borriss

Rights and permissions

About this article

Cite this article

Zverlov, V., Piotukh, K., Dakhova, O. et al. The multidomain xylanase A of the hyperthermophilic bacterium Thermotoga neapolitana is extremely thermoresistant.Appl Microbiol Biotechnol 45, 245–247 (1996). https://doi.org/10.1007/s002530050678

Download citation

Keywords