FIG. 1.
General organization of the sucrose promoter-reporter gene fusion plasmids. The common elements of each plasmid are (clockwise) a sucrose-responsive promoter (PscrY) (7), the sucrose repressor gene (scrR) (7), and the following components derived from the parental vector, pVSP61 (24): the P15a origin of replication from pACYC184, a kanamycin resistance gene (nptII), and a broad-host-range origin of replication (VS1 replicon). Promoterless reporter gene fragments (gfp, inaZ, and lacZYA) containing BamHI sites at both ends were cloned into the unique BamHI site between PscrY and scrR to create the plasmids p61RYTIR, p61RYice, and p61RYlac, respectively. The lac promoter present on pVSP61 is located immediately downstream of the HindIII site in a transcriptional orientation opposite to that of scrR. Restriction enzymes: B, BamHI; Bg, BglII; E, EcoRI; H, HindIII. ∗, EcoRI site present in p61RYTIR only; ∗∗, EcoRI site present in both p61RYTIR and p61RYice