来源于生孢噬纤维菌的木聚糖酶的异源表达及酶学性质  

Heterologous expression and characterization of xylanase from Sporocytophaga sp.CX11

作　　者：王梓懿 荆晓凤 庄迎 李宪臻[1] 陈晓艺[1] WANG Ziyi;JING Xiaofeng;ZHUANG Ying;LI Xianzhen;CHEN Xiaoyi(School of Biological Engineering,Dalian Polytechnic University,Dalian 116034,China)

机构地区：[1]大连工业大学生物工程学院,辽宁大连116034

出　　处：《大连工业大学学报》2025年第2期79-85,共7页Journal of Dalian Polytechnic University

基　　金：辽宁省教育厅重点攻关项目(LJKZZ20220061)。

摘　　要：从生孢噬纤维菌Sporocytophaga sp.CX11基因组中克隆出一个木聚糖酶基因Sm_0081,该基因大小为3093bp,编码1031个氨基酸,编码蛋白理论分子质量为109.9ku。将该基因在大肠杆菌中异源表达,经Ni-NTA亲和层析纯化获得目的蛋白。酶学性质测定结果表明,木聚糖酶Sm_0081的最适温度为45℃,最适pH为7.5;温度低于40℃和pH 5.0~9.0条件下保持稳定,酶活力最高为113.2U/mg。Sm_0081具有良好的Na Cl耐受性,Mg^(2+)对其酶活力有一定的促进作用。此外,木聚糖酶Sm_0081具有广泛的底物特异性,水解榉木木聚糖的产物以木二糖为主,其次是木三糖,随反应时间延长木糖的含量逐渐增多。木聚糖酶Sm_0081可用于低聚木糖的生产。A xylanase gene Sm_0081 was cloned from the genome of Sporocytophaga sp.CX11.The gene contains 3093 bp and encodes 1031 amino acids.The theoretical protein molecular weight is 109.9 ku.Gene Sm_0081 was heterologously expressed in Escherichia coli,and the recombinant protein Sm_0081 was purified by Ni-NTA affinity chromatography.The results of enzymatic properties showed that the optimal temperature and pH of xylanase Sm_0081 were 45℃and 7.5,respectively.The enzyme activity could reach up to 113.2 U/mg in the conditions of temperature lower than 40℃and pH 5.0 to 9.0.Xylanase Sm_0081 showed good NaCl tolerance,and Mg^(2+)has a certain promoting effect on its enzyme activity.In addition,xylanase Sm_0081 has a wide range of substrate specificity.The hydrolysis products of beech xylan are mainly xylobiose,followed by xylotriose,and the content of xylose gradually increases with the extension of reaction time.The results indicated xylanase Sm_0081 can be used to produce xylooligosaccharides.

关 键 词：生孢噬纤维菌 木聚糖酶 低聚木糖 盐耐受 

分 类 号：Q816[生物学—生物工程]