title: Cloning, expression, and characterization of a new Streptomyces sp. S27 xylanase for which xylobiose is the main hydrolysis product.
abstract: A xylanase gene, xynBS27, was cloned from Streptomyces sp. S27 and consisted of 693 bp encoding a 230-residue protein, including a putative 41-residue signal peptide. Belonging to the glycoside hydrolase family 11, XynBS27 exhibits the maximum identity (75.9%) to the xylanase from Streptomyces sp. zxy19. Recombinant XynBS27 was overexpressed in Pichia pastoris, and the xylanase activity was 7624.0 U/ml after high-cell-density fermentation in 3.7-L fermenter. The purified recombinant XynBS27 had a high specific activity of 3272.0 U/mg. The optimum temperature and pH for XynBS27 activity was 65 degrees C and pH 6.5, respectively. XynBS27 showed good pH stability and retained more than 80% of the maximum activity after incubation in buffers with pH ranging between 4.0 and 12.0 at 37 degrees C for 1 h. The main hydrolysis product of xylan by XynBS27 was xylobiose (>75%), which was good for human health derived from its ability to modulate the intestinal function. The attractive biochemical characteristics of XynBS27 suggest that it may be a good candidate in a variety of industrial applications.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Pengjun
authors.initials: P
authors.lastname: Shi
authors.forename: Peilong
authors.initials: P
authors.lastname: Yang
authors.forename: Yaru
authors.initials: Y
authors.lastname: Wang
authors.forename: Huiying
authors.initials: H
authors.lastname: Luo
authors.forename: Yingguo
authors.initials: Y
authors.lastname: Bai
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
mesh_terms: D003001:Cloning, Molecular / Q000379:methods; D004187:Disaccharides / Q000138:chemical synthesis*; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D004789:Enzyme Activation; D004795:Enzyme Stability; D006868:Hydrolysis; D010843:Pichia / Q000502:physiology*; D015202:Protein Engineering / Q000379:methods; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics*; D014990:Xylans / Q000737:chemistry*
chemical_list: D004187:Disaccharides; D011994:Recombinant Proteins; D014990:Xylans; D043364:Endo-1,4-beta Xylanases; C004173:xylobiose