摘要
应用蓝藻类金属硫蛋白启动子（ｓｍｔＯＰ）的金属诱导性，在丝状体蓝藻鱼腥藻（Ａｎａｂａｅｎａｓｐ．ＰＣＣ７１２０）中表达具有更高金属结合能力和对Ｃｄ２＋有选择特异性的小鼠金属硫蛋白基因（ｍＭＴⅠｃＤＮＡ）。构建穿梭表达载体ｐＫＴＭＲＥ并在大肠杆菌ＨＢ１０１中扩增，经三亲接合转移、链霉素筛选、ＤＮＡ和蛋白质印迹等方法鉴定得到稳定的转基因工程蓝藻。转基因蓝藻对金属离子吸附能力和较高重金属浓度下放氧活性测定表明，外源基因的表达提高了蓝藻对重金属离子的抗性，是野生蓝藻的１．５～２．０倍。
The cMT like promoter (smt O P) was used for the expression of mMT Ⅰ cDNA in cyanobacterium, Anabaena sp. PCC 7120,to enhance its metal binding ability and specificity. Shuttle vector pKT MRE was constructed and replicated in E. coli HB101, and triparental conjugate transfer was applied for transforming cyanobacterial cells. Sm screening, Southern and Western blotting analysis were used for the identification of the transgenic cyanobacterium clones. Transgenic cyanobacterial metal absorption ability,heavy metal resistance and photosynthesis measurements in the medium containing heavy metal ion indicated that the expression of foreign mMT Ⅰ enhanced the cyanobacterial heavy metal resistance to 1.5 times in the transgenic Anabaena sp. PCC 7120.
基金
国家"863"生物高技术项目
关键词
金属硫蛋白
转基因
丝状体
蓝藻
重金属抗性
mMT Ⅰ,smt O P,Transgenic filamentous cyanobacterium,Heavy metal resistance, Anabaena sp.
