Molecular Biology Reports

, Volume 37, Issue 7, pp 3297–3302

An alkali-tolerant xylanase produced by the newly isolated alkaliphilic Bacillus pumilus from paper mill effluent

  • Jing Wang
  • Wei-wei Zhang
  • Jin-ni Liu
  • Yao-ling Cao
  • Xiao-ting Bai
  • Yue-sheng Gong
  • Pei-lin Cen
  • Ming-ming Yang
Article

DOI: 10.1007/s11033-009-9915-6

Cite this article as:
Wang, J., Zhang, W., Liu, J. et al. Mol Biol Rep (2010) 37: 3297. doi:10.1007/s11033-009-9915-6

Abstract

An alkaline active xylanase, XynBYG, was purified from an alkaliphilic Bacillus pumilus BYG, which was newly isolated from paper mill effluent. It had an optimum pH of 8.0–9.0, and showed good stability after incubated at pH 9.0 for 120 min. The optimum temperature for the activity was 50°C, and the enzyme retained below 55% of its original activity for 30 min at 55°C. The gene coding for XynBYG consists of 687 bp and encodes 229 amino acids. Similarity analysis indicated that XynBYG belong to family 11 glycosyl hydrolases. Site-directed mutagenesis was performed to replace five sites (Tyr/Ser) to Arg/Glu and the results demonstrated that the optimum temperature of the mutant Y7 (S39R-T146E) increased 5°C and the half-life of inactivation (T1/2) at 60 and 65°C was 1 h and 25 min, respectively. Thus, it provides a potential xylanase that can meet the harsh conditions in the industrial applications.

Keywords

Alkali-tolerant xylanaseBacillus pumilusExpressionSite-directed mutagenesisThermostability

Supplementary material

11033_2009_9915_MOESM1_ESM.tif (1.1 mb)
Suppl 1 The nucleotide and amino acid sequence of xynBYG gene. The 27-amino acid putative signal peptide is underlined. The putative catalytic amino acids (Glu120 and Glu209) are boxed. The mutated sites are indicated by solid triangle (TIFF 1121 kb)

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Jing Wang
    • 1
  • Wei-wei Zhang
    • 1
  • Jin-ni Liu
    • 1
  • Yao-ling Cao
    • 1
  • Xiao-ting Bai
    • 1
  • Yue-sheng Gong
    • 1
  • Pei-lin Cen
    • 2
  • Ming-ming Yang
    • 1
    • 2
  1. 1.College of Animal Sciences and TechnologyNorthwest A&F UniversityYanglingPeople’s Republic of China
  2. 2.Institute of Biochemical Engineering, College of Material Science and Chemical EngineeringZhejiang UniversityHangzhouPeople’s Republic of China