Phosphate Starvation Induces the Sporulation Killing Factor of Bacillus subtilis

School of Biology and Physcology, University of Newcastle upon Tyne, Newcastle upon Tyne, NE2 4HH, United Kingdom.
Journal of Bacteriology (Impact Factor: 2.81). 08/2006; 188(14):5299-303. DOI: 10.1128/JB.00084-06
Source: PubMed


Bacillus subtilis produces and exports a peptide sporulation killing factor (SkfA) that induces lysis of sibling cells. skfA is part of the skf operon (skfA-H), which is responsible for immunity to SkfA, as well as for production and export of SkfA. Here we report that transcription
of skfA is markedly induced when cells of B. subtilis are subjected to phosphate starvation. The role of PhoP in regulation of the skf operon was confirmed by in vitro gel shift assays, which showed that this operon is a new member of the PhoP regulon. A putative
stem-loop structure in the skfA-skfB intergenic region is proposed to act as a stabilizer of an skfA-specific transcript.

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    • "The mechanism involved in the cellular phosphate response is the subject of intense investigation in prokaryotes and eukaryotes. Developmentally related events and sporulation can be triggered in bacteria by phosphate limitation (Meeks et al. 2002; Díaz et al. 2005; Allenby et al. 2006; Philippe et al. 2006). Eukaryote microorganisms, yeasts in particular, adjust phosphate acquisition and utilization during growth through a coordinated expression of genes related to phosphate metabolism, the PHO pathway (Mouillon and Persson 2006; Secco et al. 2012). "
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    • "Spo0A, a regulatory protein that governs the entry into sporulation, activates two operons skf and sdp [3] [4] [5] [6] [7]. The skf operon is responsible for the production and extracellular export of the killing factor which lyse the sister cells [8] [9]. The sdp operon synthesizes the protein responsible for delaying sporulation. "
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