SIGMA(S)-DEPENDENT OVEREXPRESSION OF FTSZ IN AN ESCHERICHIA-COLI K-12RPOB MUTANT THAT IS RESISTANT TO THE DIVISION INHIBITORS DICB AND DICF RNA

The Escherichia coli genes dicF and dicB encode division inhibitors, w hich prevent the synthesis and activity, respectively, of the essentia l division protein FtsZ. A mutation at the C-terminal end of the RNA p olymerase beta subunit renders cells resistant to both inhibitors. In the mutant strain the level of the ftsZ gene product is higher than in the wild type. Disruption of rpoS, which encodes the stationary phase sigma factor sigma(S), lowers FtsZ protein levels in the mutant, and partially restores sensitivity to the inhibitors.