CONSTRUCTION OF PRES18 AND PRES19, STREPTOMYCES ESCHERICHIA-COLI SHUTTLE VECTORS CARRYING MULTIPLE CLONING SITES

We developed two Streptomyces-Escherichia coli shuttle vectors. The pl asmid pRES102, consisting of the essential region of pRES1 and the thi ostrepton resistance gene (tsr) fragment of pIJ702, was combined with the E. coli plasmid vector pUC18 or pUC19. The resulting shuttle vecto rs, designated pRES18 and pRES19, respectively, have relatively compac t size (6.25 kb), low copy number, multiple cloning sites reciprocally arranged in opposite directions, and selection markers for both Strep tomyces (tsi) and E. coli (beta-lactamase (bla) and beta-galactosidase (lacZ)). These shuttle vectors are capable of carrying DNA fragments as long as 10 kb, of being maintained in S. griseus, S. lavendulae and S. lividans, and are compatible with pIJ702.