Definition of the σ(W) Regulon of Bacillus subtilis in the Absence of Stress

Comprison of the transcriptome of wild type Bacillus subtilis to the mutants sigW, rasP and prsW to select all candidate sigW regulated genes. We identified 89 genes as being sigW regulated, including several non-coding RNA's. The effects of rasP and prsW mutations on sigW regulated genes were relatively mild, implying that RasP or PrsW are not strictly required for sigW activation. The rasP mutant has a peliotropic phenotype, affecting competence development, protein secretion and membrane protein production. We show that these are not mirrored in the transcriptome, suggesting that RasP exerts its effects at the post transcriptional level. RNA samples prepared from B. subtilis 168 and mutants sigW, rasP, and prsW were grown in Luria Bertani broth to O.D 600nm 1.0 were reverse transcribed, labeled and hybridized to tiling arrays. All hybridizations (except prsW which was in duplicate) were performed in triplicate using RNA isolated from independent cultures.