大肠杆菌-分枝杆菌启动子探针型穿梭载体pEQ3的构建

CONSTRUCTION OF PROMOTER PROBE VECTOR pEQ3 SHUTTLING BETWEEN E.COLI AND MYCOBATERIA

报道了大肠杆菌分枝杆菌启动子探针型（ＰｒｏｍｏｔｅｒＰｒｏｂｅ）穿梭质粒ｐＥＱ３的构建过程．证明其保留了在大肠杆菌和分枝杆菌之间的穿梭功能，并具有启动子筛选功能．利用构建的ＰＥＱ３质粒。

A promoter probe shuttle vector pEQ3(Kan r,Amp r) was constructed based on Mycobacterium E.coli shuttle vector pEP2.Link pUC18 and pEP2 were linded at the Eco RⅠ site,after deleting a Bam HI site of the plasmid,the fusion vector was named pEQ3. Sau3A I fragment of BCG(Bacille Calmette Guerin) total DNA were inserted into the Bam HI site of pEQ3 and eight recombinats were obtained which showed bule clones on the X gal plate.This result indicates that the fragments carried by the recombinants contain expression signal which is functional in E.coli. The dot hybridization result of recombinant plasmids using BCG total DNA as probe shows that the foreign fragments of the recombinant plasmids come from BCG DNA.