title: Cloning, expression, and characterization of an alkaline thermostable GH11 xylanase from Thermobifida halotolerans YIM 90462T.
abstract: A xylanase gene (thxyn11A) from the Thermobifida halotolerans strain YIM 90462(T) was cloned and expressed in Escherichia coli. The open reading frame (ORF) of thxyn11A has 1,008 bp encoding a mature xylanase with a high degree of similarity (80 %) to the xylanase from Nocardiopsis dassonvillei subsp. dassonvillei DSM 43111. This enzyme (Thxyn11A) also possesses a glycosyl hydrolases family 11 (GH11) domain and a high isoelectric point (pI = 9.1). However, Thxyn11A varies from most GH11 xylanases, due to its large molecular mass (34 kDa). Recombinant Thxyn11A demonstrated a strong pH and temperature tolerance with a maximum activity at pH 9.0 and 70 °C. Xylotriose, the end-product of xylan hydrolysis by Thxyn11A, serves as a catalyst for hemicellulose pretreatment in industrial applications and can also function as a food source or supplement for enterobacteria. Due to its attractive biochemical properties, Thxyn11A may have potential value in many commercial applications.
authors.affiliation: Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, 650091, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.forename: Jiu-Jiu
authors.initials: JJ
authors.lastname: Chen
authors.forename: Wan-Zeng
authors.initials: WZ
authors.lastname: Ren
authors.forename: Lian-Bing
authors.initials: LB
authors.lastname: Lin
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhou
authors.forename: Xiao-Yang
authors.initials: XY
authors.lastname: Zhi
authors.forename: Shu-Kun
authors.initials: SK
authors.lastname: Tang
authors.forename: Wen-Jun
authors.initials: WJ
authors.lastname: Li
mesh_terms: D000192:Actinomycetales / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D001709:Biotechnology; D003001:Cloning, Molecular; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis / Q000187:drug effects; D007526:Isoelectric Point; D007700:Kinetics; D010802:Phylogeny; D013379:Substrate Specificity; D013696:Temperature; D014312:Trisaccharides / Q000378:metabolism; D014990:Xylans / Q000378:metabolism
chemical_list: D014312:Trisaccharides; D014990:Xylans; C515044:xylotriose; D043364:Endo-1,4-beta Xylanases