Expression of a pepT homologue from Bacillus subtilis.

We isolated pepT from Bacillus subtilis, a gene with homology to various tripeptidases from different bacterial sources. pepT is preceded by genes encoding a two component regulatory system. Its expression is activated during stationary phase. In minimal medium this activation is boosted in the presence of phosphate. The response regulator is preceded by putative promoter consensus sequences recognized by the stationary phase specific sigma factors sigma H, sigma F, and sigma G. This is in accordance with the initiation of expression at the beginning of stationary phase. Inactivation of pepT causes no obvious phenotype.