title: Engineering a xylanase from Streptomyce rochei L10904 by mutation to improve its catalytic characteristics.
abstract: Protein engineering was performed by N-terminal region replacement and site-directed mutagenesis in the cord of a xylanase (Srxyn) from Streptomyce rochei L10904 to improve its catalytic characteristics. Three mutants SrxynF, SrxynM and SrxynFM displayed 2.1-fold, 3.2-fold and 5.3-fold higher specific activities than that of Srxyn, respectively. Moreover, all of the mutants showed greater substrate affinity and kcat/Kmthan the native Srxyn. In addition, the enzymes showed improved hydrolysis characteristics, of which the most noteworthy is the enhanced ability of producing xylobiose (X2) and xylotriose (X3) from polymeric substrates. The engineered xylanases have greater potential for applications in oligosaccharide preparation industry.
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China; School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
authors.affiliation: School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China; Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing 100048, China.
authors.forename: Baoguo
authors.initials: B
authors.lastname: Sun
authors.affiliation: Department of Biology, Emory University, 1510 Clifton Road, Atlanta, GA 30322, USA.
authors.forename: Huiyong
authors.initials: H
authors.lastname: Jia
authors.affiliation: School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Hou
authors.affiliation: School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Yang
authors.affiliation: School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Xiong
authors.affiliation: Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing 100048, China.
authors.forename: Youqiang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China; School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China. Electronic address: lixt@btbu.edu.cn.
authors.forename: Xiuting
authors.initials: X
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D055162:Biocatalysis; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004795:Enzyme Stability; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D011487:Protein Conformation; D015202:Protein Engineering; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity; D013696:Temperature; D014990:Xylans / Q000378:metabolism
chemical_list: D014990:Xylans; D043364:Endo-1,4-beta Xylanases
keywords: Catalytic characteristics; Cord; N-terminal; Xylanase