A Novel marRAB Operon Contributes to the Rifampicin Resistance in Mycobacterium smegmatis
Figure 6
Expression assays for the effect of MarR on the target gene in wildtype and marR -deleted mutant strains.
(A) Determination of β-galactosidase activity (Miller units). The values presented represent averages of three independent experiments. For statistical analysis, two-way ANOVA with Bonferroni multiple comparison tests were performed. P≤0.05 was considered statistically significant. (B) Quantitative real-time PCR assays for differential expression of the target genes in wildtype, mutant and complementation strains (left panel), and the marR overexpression strain (right panel). Relative expression levels of the genes were normalized using the SigA gene as an invariant transcript, and an unrelated Ms6141 gene as a negative control. Data were analyzed using the 2ΔΔCt method [21]. Relative expression data were analyzed for statistical significance by the unpaired two-tailed Student’s T-test using GraphPad Prism (Version 5).
