大肠杆菌ispB基因的克隆及鉴定

Cloning and identification of E.coli ispB gene

ispB基因编码八聚异戊二烯焦磷酸合成酶 ,是决定大肠杆菌CoQ8生物合成的关键因子。克隆ispB基因是构建产辅酶Q10 基因工程菌的前提。本实验从野生型大肠杆菌MC4 10 0出发 ,以 pUC18为载体 ,构建了大肠杆菌SspI限制性基因文库。筛选得到目的重组子 pXF98,其酶切鉴定图谱与实验期望值吻合。测序结果表明 。

The isp B gene encoded the octaprenyl diphosphate synthetase was the key factor defining the type of ubiquinone 8 in E.coli . It was necessary to obtain the isp B gene to construct the genetic engineering strain E.coli for producing CoQ 10 . In this study, A SspI restriction gene library was constructed with plasmid pUC18 and the chromo somal DNA of E.coli MC4100. The recombinant plasmid pXF98 was selected to sequence which had the restriction map as well as the expectation one. The sequence result indicated that the fragment cloned in pXF98 contained an intact isp B gene which had the same sequence as that of E.coli K 12.