Regulation of Bacillus subtilis senS by homologous regulatory regions of senS and the inducible cat gene.

We have identified a stem-and-loop region between the promoter and open reading frame of the Bacillus subtilis senS gene containing a 9 base sequence (TTTAGATAA) identical to a sequence found in a similar regulatory element of the inducible pC194 cat gene. A high copy number of this pC194 regulatory region repressed the expression of senS, indicating that the stem-and-loop region of the cat gene titrated a positive factor necessary for senS expression. These results suggest that factors with similar binding requirements control senS and cat expression. In addition, senS was found to be autoregulated.