Inhibition of Bacillus subtilis scoC expression by multicopy senS.

The Bacillus subtilis aprE gene, which encodes the extracellular alkaline protease, is regulated by many positive and negative transcriptional regulators. SenS is one such positive regulator consisting of 65 amino acids. We found that the senS gene on a multicopy plasmid, pSEN24, caused an increase in aprE expression in strains carrying the upstream region of aprE up to -340 with respect to the transcription initiation site but not in a strain carrying the region up to -299, which is within the binding site of the negative regulator ScoC (Hpr).

Inhibition of Bacillus subtilis aprE expression by lincomycin at the posttranscriptional level through inhibition of ppGpp synthesis.

Expression of the Bacillus subtilis alkaline protease gene aprE is controlled by many positive and negative regulators at the transcriptional level. During the course of screening for organic compounds that affect the expression of a translational aprE'-'lacZ fusion, we found that lincomycin (Lm), erythromycin and chloramphenicol exhibited an inhibitory effect in concentrations that hardly affected cell growth. The antibiotics are known to inhibit protein synthesis by binding to ribosomes.