title: A xylanase gene directly cloned from the genomic DNA of alkaline wastewater sludge showing application potential in the paper industry.
abstract: A xylanase gene, aws-2x, was directly cloned from the genomic DNA of the alkaline wastewater sludge using degenerated PCR and modified TAIL-PCR. The deduced amino acid sequence of AWS-2x shared the highest identity (60%) with the xylanase from Chryseobacterium gleum belonging to the glycosyl hydrolase GH family 10. Recombinant AWS-2x was expressed in Escherichia coli BL21 (DE3) and purified to electrophoretic homogeneity. The enzyme showed maximal activity at pH 7.5 and 55 °C, maintained more than 50% of maximal activity when assayed at pH 9.0, and was stable over a wide pH range from 4.0 to 11.0. The specific activity of AWS-2x towards hardwood xylan (beechwood and birchwood xylan) was significantly higher than that to cereal xylan (oat spelt xylan and wheat arabinoxylan). These properties make AWS-2x a potential candidate for application in the pulp and paper industry.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081, People's Republic of China. zhaoyanyu1986@sohu.com
authors.forename: Yanyu
authors.initials: Y
authors.lastname: Zhao
authors.forename: Huiying
authors.initials: H
authors.lastname: Luo
authors.forename: Kun
authors.initials: K
authors.lastname: Meng
authors.forename: Pengjun
authors.initials: P
authors.lastname: Shi
authors.forename: Guozeng
authors.initials: G
authors.lastname: Wang
authors.forename: Peilong
authors.initials: P
authors.lastname: Yang
authors.forename: Tiezheng
authors.initials: T
authors.lastname: Yuan
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
mesh_terms: D003001:Cloning, Molecular; D043364:Endo-1,4-beta Xylanases / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D010209:Paper; D012722:Sewage; D014990:Xylans / Q000378:metabolism
chemical_list: D012722:Sewage; D014990:Xylans; D043364:Endo-1,4-beta Xylanases