工程菌BL21-PET21a(+)-phy A表达植酸酶的研究  

Studies on the Expression of Aspergillus niger Phytase in E.coil BL21-PET21a(+)phyA

作　　者：魏威[1] 李弘剑[1] 李月琴[1] 方玲[1] 陈浩军[1] 周乐平[1] 何华坤[1] 周天鸿[1] 

机构地区：[1]暨南大学生物工程学系,广州510632

出　　处：《中国生物工程杂志》2004年第1期66-69,共4页China Biotechnology

基　　金：广东省自然科学基金资助项目 ( 990 869;98 0 6 94)

摘　　要：对来源于Aspergillusniger的植酸酶基因phyA进行了改造 ,去除了内含子和信号肽编码序列后重组到表达载体PET2 1a( + )上 ,导入大肠杆菌BL2 1 (DE3)中 ,构建工程菌株BL2 1 PET2 1a( + ) phyA。植酸酶基因在工程菌株中得到了高效表达。表达产物主要以包涵体形式存在 ,表达量达到菌体蛋白的 30 %以上。改进了包涵体复性技术 ,包涵体蛋白经复性、纯化后 ,生物活性达到 1 5 0 0U mg ,并且复性蛋白具有较好的热稳定性 ,经过 75～ 95℃、30min的热处理后 ,仍然保持了生物活性 ,同时有明显的热激活现象。热激活后最高生物活性达到 5 0 0 0U mg。The gene(phyA) for Aspergillus niger phytase without original signal peptide and intron was cloned into E.coil expression plasmid PET21a(+). The recombined plasmid PET21a(+)\|phyA was overexpressed in E.coil BL21, the most of expressive protein was in the form of inclusion body.The method for renaturation was improved.The biology activity of renaturative protein reached 1500U/mg.The renaturative protein has better thermostability,the protein, after heat treatment 75～95℃ 30min, still kept biological activity and has the phenomenon of activation.The highest biology activity reached 5000U/mg.;

关 键 词：植酸酶 高效表达 包涵体 复性 热稳定性 工程菌 

分 类 号：Q786[生物学—分子生物学]