Figure 5.

DNA gyrase influences expression at high activity insertion sites. (A) pBR322 plasmid was used as a reporter of DNA superhelicity during growth with increasing concentrations of novobiocin. Plasmid DNA was separated on a 1% agarose gel supplemented with 2.5 μg/ml chloroquine. Ethidium bromide stained DNA was visualized under UV light. (B) Fluorescence output from the reporter cassette at the nupG, asl and lac positions, during growth in the presence of 100 μM IPTG and increasing concentrations of novobiocin.