title: Cross-talk between the general stress response and sporulation initiation in Bacillus subtilis - the σ(B)  promoter of spo0E represents an AND-gate.
abstract: The general stress response and the decision-making processes of sporulation initiation are interconnected pathways in the regulatory network of Bacillus subtilis. In a previous study we provided evidence for a mechanism capable of impairing sporulation by σ(B) -dependent induction of spo0E, encoding a phosphatase specifically inactivating the sporulation master regulator Spo0A~P. Here we show that the σ(B) promoter (Pσ(B)) of spo0E is responsive to sub-inhibitory levels of ethanol stress, producing a σ(B) -dependent sporulation deficient phenotype. In addition to positive regulation by σ(B) , we identified Rok, the repressor of comK, to be a direct repressor of spo0E expression from Pσ(B) . This constellation provides the possibility to integrate signals negatively acting on sporulation initiation through the σ(B) branch as well as a positive feedback loop acting on Pσ(B) by Rok that is most likely a direct consequence of Spo0A~P activity. Thus, the molecular mechanism described here offers the opportunity for cross-talk between the general stress response and sporulation initiation in the adaptational gene expression network of B. subtilis.
authors.affiliation: Institute of Microbiology, Ernst-Moritz-Arndt-University, F- L-Jahn-Straße 15, D-17487 Greifswald, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Reder
authors.forename: Dirk
authors.initials: D
authors.lastname: Albrecht
authors.forename: Ulf
authors.initials: U
authors.lastname: Gerth
authors.forename: Michael
authors.initials: M
authors.lastname: Hecker
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D000431:Ethanol / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D013171:Spores, Bacterial / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D014157:Transcription Factors; D000431:Ethanol; D010744:Phosphoric Monoester Hydrolases