Applied Microbiology and Biotechnology

, 84:1107

Gene cloning, expression and characterization of a new cold-active and salt-tolerant endo-β-1,4-xylanase from marine Glaciecola mesophila KMM 241

Authors

  • Bing Guo
    • The State Key Lab of Microbial Technology, Marine Biotechnology Research CenterShandong University
    • The State Key Lab of Microbial Technology, Marine Biotechnology Research CenterShandong University
  • Cai-Yun Sun
    • The State Key Lab of Microbial Technology, Marine Biotechnology Research CenterShandong University
  • Bai-Cheng Zhou
    • The State Key Lab of Microbial Technology, Marine Biotechnology Research CenterShandong University
  • Yu-Zhong Zhang
    • The State Key Lab of Microbial Technology, Marine Biotechnology Research CenterShandong University
Biotechnologically Relevant Enzymes and Proteins

DOI: 10.1007/s00253-009-2056-y

Cite this article as:
Guo, B., Chen, X., Sun, C. et al. Appl Microbiol Biotechnol (2009) 84: 1107. doi:10.1007/s00253-009-2056-y

Abstract

Although a lot of xylanases are studied, only a few xylanases from marine microorganisms have been reported. A new xylanase gene, xynA, was cloned from marine bacterium Glaciecola mesophila KMM 241. Gene xynA contains 1,272 bp and encodes a 423-amino acid xylanase precursor. The recombinant xylanase, XynA, expressed in Escherichia coli BL21 is a monomer with a molecular mass of 43 kDa. Among the characterized xylanases, XynA shares the highest identity (46%) to the xylanase from Flavobacterium sp. strain MSY2. The optimum pH and temperature for XynA is 7.0 and 30 °C. XynA retains 23% activity and 27% catalytic efficiency at 4 °C. XynA has low thermostability, remaining 20% activity after 60-min incubation at 30 °C. Its apparent melting temperature (Tm) is 44.5 °C. These results indicate that XynA is a cold-active xylanase. XynA shows a high level of salt-tolerance, with the highest activity at 0.5 M NaCl and retaining 90% activity in 2.5 M NaCl. It may be the first salt-tolerant xylanase reported. XynA is a strict endo-β-1,4-xylanase with a demand of at least four sugar moieties for effective cleavage. It efficiently hydrolyzes xylo-oligosaccharides and xylan into xylobiose and xylotriose without producing xylose, suggesting its potential in xylo-oligosaccharides production.

Keywords

XylanaseXynACold-activeSalt-tolerantGlaciecola mesophilaMarineXylan

Supplementary material

253_2009_2056_MOESM1_ESM.doc (348 kb)
ESM 1(DOC 347 kb)

Copyright information

© Springer-Verlag 2009