Fig. 7.

FlhDC and FliA inversely regulate RsmB at a post-transcriptional level.

A. Promoter activity of rsmB was measured in the wild-type D. dadantii, the flhDC mutant and the fliA mutant strains.

B. Northern blot analysis of rsmB mRNA in the wild-type D. dadantii harbouring empty vector pCL1920, ΔfliA harbouring empty vector pCL1920, ΔfliA harbouring plasmid pCL1920-fliA, ΔflhDC harbouring empty pCL1920 and ΔflhDC harbouring pCL1920-flhDC. 16S rRNA was used as RNA loading control.

C. Pectate lyase production assay was performed in the wild-type D. dadantii harbouring empty vector pCL1920, ΔfliA harbouring empty vector pCL1920, ΔfliA harbouring plasmid pCL1920-fliA, ΔflhDC harbouring empty pCL1920 and ΔflhDC harbouring pCL1920-flhDC. Values are a representative of three independent experiments. Three replicates were used in each experiment. Error bars indicate standard errors of the means. Asterisks indicate statistically significant differences of the means (P < 0.05 by Student’s t-test).