Figure 3. Topology-dependent transcription of P_tccat is dependent on its chromosomal location.

Transcriptional response to DNA relaxation by novobiocin measured by qRT−PCR. Exponentially growing cultures of the R6-CAT strains at OD_620nm = 0.4 were treated with novobiocin at 10× MIC. Total RNA was isolated; cDNA was synthesized and subjected to qRT−PCR. To normalize the three independent replicate samples, values were divided by those obtained of an internal fragment of the 16SrDNA gene. These normalized values were made relative to those obtained at time 0 min. Fold change represented the log2 mean of qRT-PCR values of three independent replicates ± SEM.