Insulation of the sigmaF regulatory system in Bacillus subtilis.

The transcription factors sigmaF and sigmaB are related RNA polymerase sigma factors that govern dissimilar networks of adaptation to stress conditions in Bacillus subtilis. The two factors are controlled by closely related regulatory pathways, involving protein kinases and phosphatases. We report that insulation of the sigmaF pathway from the sigmaB pathway involves the integrated action of both the cognate kinase and the cognate phosphatase.