短小芽孢杆菌β-1,4-木聚糖酶基因在大肠杆菌中的高效表达  

Overexpression of Bacillus pumilus β-1,4-Xylanase Gene (xynA ) in Escherichia coli

作　　者：刘伟丰[1] 毛爱军[1] 祝令香[1] 乔宇[1] 于巍[1] 董志扬[1] 

机构地区：[1]中国科学院微生物研究所,北京100080

出　　处：《农业生物技术学报》2004年第4期455-459,共5页Journal of Agricultural Biotechnology

基　　金：国家高技术研究与发展计划(863)项目(No. 2001AA214161.);中国科学院知识创新方向性课题(No. KJCX2-SW-206-1)。

摘　　要：从短小芽孢杆菌(Bacilluspumilus)BP51中克隆得到木聚糖酶基因xynA。将其构建在大肠杆菌(Escherichiacoli)表达载体pET21a上,转化E.coli BL21,获得重组工程菌BLX5。经IPTG诱导,xynA基因的表达产物以胞内可溶性蛋白和包涵体形式存在。重组表达木聚糖酶的活力可达165.51 IU/mL培养物。重组表达的木聚糖酶最适温度为55 ℃,最适pH值为6.5,在碱性条件下具有良好的稳定性,降解产物以三糖、四糖和五糖为主。The xylanase-encoding gene xynA was cloned from Bacillus pumilus BP51, inserted into expression vector pET21a and transformed into Escherichia coli BL21 (DE3), finally the recombinant strain BLX5 was obtained. Induced by IPTG, the xynA gene was expressed in the recombinant strain BLX5. And its expression products existed as both soluble proteins and inclusion bodies. The recombinant expression xylanase activity reached to 165.51 IU/mL. The optimum temperature and pH of the recombinant expression xylanase were 55℃ and pH 6.5 respectively. And the recombinant expressed xylanase was stable in alkalitropic condition. Andits hydrolysis products were mainly trisachharides, tetrasaccharides and pentasaccharides.

关 键 词：短小芽孢杆菌 木聚糖酶基因 大肠杆菌 高效表达 β-1 重组表达 可溶性蛋白 最适PH值 表达载体 IPTG 表达产物 NA基因 最适温度 碱性条件 降解产物 工程菌 培养物 稳定性 克隆 体形 活力 

分 类 号：Q786[生物学—分子生物学] TQ920.1[轻工技术与工程—发酵工程]