title: Engineering a high-performance, metagenomic-derived novel xylanase with improved soluble protein yield and thermostability.
abstract: The novel termite gut metagenomic-derived GH11 xylanase gene xyl7 was expressed in Escherichia coli BL21, and the purified XYL7 enzyme exhibited high specific activity (6340U/mg) and broad pH active range of 5.5-10.0. Directed evolution was employed to enhance the thermostability of XYL7; two mutants (XYL7-TC and XYL7-TS) showed a 250-fold increase in half-life at 55°C, with a 10°C increase in optimal temperature compared to that of wild-type XYL7. A truncated enzyme (XYL7-Tr3) acquired by protein engineering showed similar catalytic properties as the wild-type, with a tenfold increase in soluble protein yield by the mutant. The reducing sugar produced by XYL7-TC was about fourfold greater than that produced by their parents when incubated with xylan at 60°C for 4h. The engineered novel xylanase exhibited superior enzymatic performance and showed promise as an excellent candidate for industrial application due to its high specific activity, stability and soluble protein yield.
authors: Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China.
authors: Changli
authors: C
authors: Qian
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China.
authors: Ning
authors: N
authors: Liu
authors: Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China.
authors: Xing
authors: X
authors: Yan
authors: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China.
authors: Qian
authors: Q
authors: Wang
authors: Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China. Electronic address: zhouzhihua@sippe.ac.cn.
authors: Zhihua
authors: Z
authors: Zhou
authors: Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Fenglin Rd 300, Shanghai 200032, China. Electronic address: qfwang01@sibs.ac.cn.
authors: Qianfu
authors: Q
authors: Wang
mesh_terms: D000818:Animals; D001709:Biotechnology; D003001:Cloning, Molecular; D043364:Endo-1,4-beta Xylanases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D004795:Enzyme Stability; D017344:Genes, Insect; D006358:Hot Temperature; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D020049:Isoptera / Q000201:enzymology / Q000235:genetics; D007700:Kinetics; D054892:Metagenome; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015202:Protein Engineering; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012995:Solubility; D013696:Temperature; D014990:Xylans / Q000378:metabolism
chemical_list: D019476:Insect Proteins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D014990:Xylans; D043364:Endo-1,4-beta Xylanases
keywords: Directed molecular evolution; GH11 xylanase; Metagenomic; Protein engineering; Thermostability