title: Overexpression of a Paenibacillus campinasensis xylanase in Bacillus megaterium and its applications to biobleaching of cotton stalk pulp and saccharification of recycled paper sludge.
abstract: A xylanase gene (xynG1-1) from Paenibacillus campinasensis G1-1 was expressed in Bacillus megaterium MS941 and a high level of extracellular xylansae activity (304.26 IU/mL) was achieved after induction with 0.5% xylose. The purified recombinant xylanase (XynG1-1R) revealed optimal activity at 60°C and pH 7.0 and retained 79% and 81% activity after incubation without substrate at 60°C, pH 5.0 and pH 8.0 for 3h, respectively. Application of XynG1-1R (15 IU/g pulp) to cotton stalk pulp bleaching increased brightness by 3.65% over that of the control without the xylanase and reduced the need for chlorine compounds by 50% without loss of brightness and pulp fiber qualities. When XynG1-1R (80 IU/g paper sludge) was used in combination with mixed cellulolytic enzymes, the saccharification efficiency of recycled paper sludge was increased by 10%. These results indicated that XynG1-1R is a promising candidate for various industrial applications such as biobleaching and bioenergy conversion.
authors.affiliation: Key Laboratory of Industrial Fermentation Microbiology, Education Ministry of China, Tianjin 300457, China.
authors.forename: Hongchen
authors.initials: H
authors.lastname: Zheng
authors.forename: Yihan
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Liu
authors.forename: Yang
authors.initials: Y
authors.lastname: Han
authors.forename: Jianling
authors.initials: J
authors.lastname: Wang
authors.forename: Fuping
authors.initials: F
authors.lastname: Lu
mesh_terms: D001410:Bacillus megaterium / Q000201:enzymology* / Q000235:genetics; D003116:Color; D043364:Endo-1,4-beta Xylanases / Q000235:genetics / Q000378:metabolism*; D003368:Gossypium / Q000382:microbiology*; D056507:Paenibacillus / Q000201:enzymology* / Q000235:genetics; D010209:Paper; D035261:Plant Components, Aerial / Q000382:microbiology; D010936:Plant Extracts / Q000378:metabolism; D015202:Protein Engineering / Q000379:methods; D059027:Recycling; D012722:Sewage / Q000382:microbiology*; D015854:Up-Regulation; D014994:Xylose / Q000096:biosynthesis*
chemical_list: D010936:Plant Extracts; D012722:Sewage; D014994:Xylose; D043364:Endo-1,4-beta Xylanases