title: Investigating the expression of F10 and G11 xylanases in Aspergillus niger A09 with qPCR.
abstract: There exist significant differences between the 2 main types of xylanases, family F10 and G11. A clear understanding of the expression pattern of microbial F10 and G11 under different culture conditions would facilitate better production and industrial application of xylanase. In this study, the fungal xylanase producer Aspergillus niger A09 was systematically investigated in terms of induced expression of xylanase F10 and G11. Results showed that carbon and nitrogen sources could influence xylanase F10 and G11 transcript abundance, with G11 more susceptible to changes in culture media composition. The most favorable carbon and nitrogen sources for high G11 and low F10 production by A. niger A09 were xylan (2%) and (NH4)2C2O4 (0.3%), respectively. Following cultivation at 33 °C for 60 h, the highest xylanase activity (1132 IU per gram of wet mycelia) was observed. On the basis of differential gene expression of F10 and G11, as well as their different properties, we deduced that the F10 protein initially targeted xylan and hydrolyzed it into fragments including xylose, after which xylose acted as the inducer of F10 and G11 gene expression. These speculations also accounted for our failure to identify conditions favoring the high production of F10 but a low production of G11.
authors.affiliation: a College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China.
authors.forename: Shixiu
authors.initials: S
authors.lastname: Cui
authors.affiliation: b School of Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China.
authors.forename: Tianwen
authors.initials: T
authors.lastname: Wang
authors.affiliation: c Institute of Biology Co., Ltd., Henan Academy of Sciences, Zhengzhou 450008, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Hu
authors.affiliation: a College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China.
authors.forename: Liangwei
authors.initials: L
authors.lastname: Liu
authors.affiliation: a College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China.
authors.forename: Andong
authors.initials: A
authors.lastname: Song
authors.affiliation: a College of Life Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China.
authors.forename: Hongge
authors.initials: H
authors.lastname: Chen
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology*; D002244:Carbon / Q000378:metabolism; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D006868:Hydrolysis; D009584:Nitrogen / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D002244:Carbon; D043364:Endo-1,4-beta Xylanases; D009584:Nitrogen
keywords: Aspergillus niger; F10 xylanase; G11 xylanase; expression pattern; profil d’expression; qPCR; xylanase F10; xylanase G11