[The construction of shuttle plasmid vector of Streptomyces and E. coli]

A shuttle plasmid vector, pSE-3 was constructed using the Streptomyces plasmid pIJ486 and E. coli plasmid pGEM-3 digested with BgIII and BamHI respectively. The shuttle plasmid pSE-3 could replicate and express its neomycin resistance in both Streptomyces and E. coli well. The pSE-3 has opposed promoters containing bacteriophage ST6 and T7, the restriction enzyme digestion showed that the pSE-3 has a single site with HindIII and EcoRI respectively, it is very useful for the cloning and expression of the valuable gene inserts. The pSE-3 is stable in both of Streptomyces and E. coli after re-transformed pSE-3 is re-transformed from Streptomyces into E. coli and some 50 generations are propagated.