Transient heterogeneity in extracellular protease production by Bacillus subtilis
Open Access
- 1 January 2008
- journal article
- Published by Springer Science and Business Media LLC in Molecular Systems Biology
- Vol. 4 (1), 184
- https://doi.org/10.1038/msb.2008.18
Abstract
The most sophisticated survival strategy Bacillus subtilis employs is the differentiation of a subpopulation of cells into highly resistant endospores. To examine the expression patterns of non‐sporulating cells within heterogeneous populations, we used buoyant density centrifugation to separate vegetative cells from endospore‐containing cells and compared the transcriptome profiles of both subpopulations. This demonstrated the differential expression of various regulons. Subsequent single‐cell analyses using promoter‐gfp fusions confirmed our microarray results. Surprisingly, only part of the vegetative subpopulation highly and transiently expresses genes encoding the extracellular proteases Bpr (bacillopeptidase) and AprE (subtilisin), both of which are under the control of the DegU transcriptional regulator. As these proteases and their degradation products freely diffuse within the liquid growth medium, all cells within the clonal population are expected to benefit from their activities, suggesting that B. subtilis employs cooperative or even altruistic behavior. To unravel the mechanisms by which protease production heterogeneity within the non‐sporulating subpopulation is established, we performed a series of genetic experiments combined with mathematical modeling. Simulations with our model yield valuable insights into how population heterogeneity may arise by the relatively long and variable response times within the DegU autoactivating pathway.This publication has 67 references indexed in Scilit:
- Bet-hedging and epigenetic inheritance in bacterial cell developmentProceedings of the National Academy of Sciences, 2008
- Basal expression rate of comK sets a ‘switching‐window’ into the K‐state of Bacillus subtilisMolecular Microbiology, 2007
- The putative ABC transporter YheH/YheI is involved in the signalling pathway that activates KinA during sporulation initiationFEMS Microbiology Letters, 2006
- Stochasticity in gene expression: from theories to phenotypesNature Reviews Genetics, 2005
- Phosphatases modulate the bistable sporulation gene expression pattern in Bacillus subtilisMolecular Microbiology, 2005
- Stripping Bacillus: ComK auto‐stimulation is responsible for the bistable response in competence developmentMolecular Microbiology, 2005
- The Program of Gene Transcription for a Single Differentiating Cell Type during Sporulation in Bacillus subtilisPLoS Biology, 2004
- Involvement of Stringent Factor RelA in Expression of the Alkaline Protease Gene aprE in Bacillus subtilisJournal of Bacteriology, 2001
- Altering the level and regulation of the major sigma subunit of RNA polymerase affects gene expression and development in Bacillus subtilisMolecular Microbiology, 1996
- A functional Spo0A is required for maximal aprE expression in Bacillus subtilisFEBS Letters, 1996