Figure 7.

Characterization of UP-lac hybrids promoters in vivo. (A) Effect of the location of UP elements on promoter activity. The β-galactosidase activity of OK6201 cells harboring the indicated promoter-lacZ fusion plasmids were determined. Bars are expressed in Miller units (13). The value is an average obtained from two independent experiments. (B) Analysis of the transcription start site. Total RNAs (100 μg) prepared from KI70 (Δlac) (lane 2) and OK6201 (Δlac crp⁻) (lanes 3–5) cells harboring the indicated plasmids were subjected to S1 nuclease assay.