Fig 11. The effect of mutated Fis binding sites to individual promoters P_lapA6 and P_lapA7.

B-galactosidase (β-Gal) activity expressed from the lapA promoter-lacZ reporter constructs. (A) P_lapA6 promoter construct with or without mutated Fis-A4 binding site was cloned into medium-copy plasmid pBLKT and low-copy plasmid p9TT_BlacZ. p9_P_lapA6B, p9_P_lapA6B_F4mut, (B) pB_P_lapA6B, pB_P_lapA6B_F4mut, (C) p9_P_lapA7 and p9_P_lapA7_F5mut were measured in P. putida wild-type strain PSm and fis overexpression strain F15 grown in LB medium with or without 1 mM IPTG for 18 hours. Schemes of Fis binding sites (shown as grey boxes) are shown below the diagrams. Dotted lines denote mutated Fis binding sites and mutated promoter P_lapA6, lacZ reporter gene is shown as a black arrow and promoters P_lapA6 and P_lapA7 as white boxes. The scheme is not to scale. Vertical bars denote 95% confidence intervals of means. Data of at least 9 independent measurements is shown. Letters a–e depict homogeneity groups according to ANOVA post hoc Bonferroni test. Within subfigures, identical letters denote non-significant differences (P>0.05) between averages of β-galactosidase activity.