Abstract
Three promoters, located upstream of the rpoE gene encoding an extracytoplasmic sigma factor σ E, direct expression of the rpoE operon (rpoE, rseA, rseB, rseC) in Salmonella enterica serovar Typhimurium (S. Typhimurium). One of them, rpoEp3, has been found to be directly recognized by RNA polymerase containing sigma factor σ E. Using the Northern blot analysis we detected a complex pattern of transcripts indicating an internal promoter in the coding region of the rpoE gene. The promoter, rseAp, has been located by S1 mapping analysis. Its proposed −10 and −35 elements with 15 intervening nucleotides exhibited high similarity with the consensus sequence of σ E promoters, suggesting the direct dependence of rseAp upon σ E. Activity of rseAp increased towards stationary phase, after heat shock, cold shock, and in the presence of artificially induced rpoE expression, the conditions previously shown to activate σ E-dependent promoters. In vivo experiments revealed increase of the rseAp activity during growth and confirmed its clear dependence upon σ E. The proposed role of the internal rseAp promoter is to facilitate a feedback control of σ E level after the envelope stress is removed.
Similar content being viewed by others
Abbreviations
- LB:
-
Luria-Bertani
- TSP:
-
transcription start point
References
Ades S.E., Connolly L.E., Alba B.M. & Gross C.A. 1999. The Escherichia coli σ E-dependent extracytoplasmic stress response is controlled by the regulated proteolysis of an anti-σ factor. Genes Dev. 13: 2449–2461.
Ades S.E., Grigorova I.L. & Gross C.A. 2003. Regulation of the alternative sigma factor σ E during initiation, adaptation, and shutoff of the extracytoplasmic heat shock response in Escherichia coli. J. Bacteriol. 185: 2512–2519.
Alba B.M., Leeds J.A., Onufryk C., Lu C.Z. & Gross C.A. 2002. DegS and YaeL participate sequentially in the cleavage of RseA to activate the σ E-dependent extracytoplasmic stress response. Genes Dev. 16: 2156–2168.
Ausubel F.M., Brent R., Kingston R.E., Moore D.O., Seidman J.S., Smith J.A. & Struhl K. 1995. Current Protocols in Molecular Biology. Wiley, New York.
Campbell E.A., Tupy J.L., Gruber T.M., Wang S., Sharp M.M., Gross C.A. & Darst S.A. 2003. Crystal structure of Escherichia coli σ E with the cytoplasmic domain of its anti-σ RseA. Mol. Cell 11: 1067–1078.
Cezairliyan B.O. & Sauer R.T. 2007. Inhibition of regulated proteolysis by RseB. Proc. Natl. Acad. Sci. USA 104: 3771–3776.
Chaba R., Grigorova I.L., Flynn J.M., Baker T.A. & Gross C.A. 2007. Design principles of the proteolytic cascade governing the σ E-mediated envelope stress response in Escherichia coli: keys to graded, buffered, and rapid signal transduction. Genes Dev. 21: 124–136.
De Las Penas A., Connolly L. & Gross C.A. 1997. The σ E-mediated response to extracytoplasmic stress in Escherichia coli is transduced by RseA and RseB, two negative regulators of σ E. Mol. Microbiol. 24: 373–385.
Flynn J.M., Neher S.B., Kim Y.I., Sauer R.T. & Baker T.A. 2003. Proteomic discovery of cellular substrates of the ClpXP protease reveals five classes of ClpX-recognition signals. Mol. Cell 11: 671–683.
Grigorova I.L., Chaba R., Zhong H.J., Alba B.M., Rhodius V., Herman H. & Gross C.A. 2004. Fine-tuning of the Escherichia coli σ E envelope stress response relies on multiple mechanisms to inhibit signal-independent proteolysis of the transmembrane anti-σ factor, RseA. Genes Dev. 18: 2686–2697.
Heseith S.K. & Stocker B.A.D. 1981. Aromatic-dependent Salmonella typhimurium are non-virulent and effective as live vaccines. Nature 291: 238–239.
Humphreys S., Stevenson A., Bacon A., Weihardt A.B. & Roberts M. 1999. The alternative sigma factor, σ E, is critically important for the virulence of Salmonella typhimurium. Infect. Immun. 67: 1560–1568.
Koo M.S., Lee J.H., Rah S.Y., Yeo W.S., Lee J.W., Lee K.L, Koh Y.S., Kang S.O. & Roe J.H. 2003. A reducing system of the superoxide sensor SoxR in Escherichia coli. EMBO J. 22: 2614–2622.
Kormanec J. 2001. Analyzing the developmental expression of σ factors with S1-nuclease mapping, pp. 481–494. In: Chein C.H. (ed.), Nuclease Methods and Protocols, Methods in Molecular Biology 160, Humana Press, Totowa, NJ.
Linn T. & St Pierre R. 1990. Improved vector system for constructing transcriptional fusions that ensures independent translation of lacZ. J. Bacteriol. 172: 1077–1084.
Maxam A.M. & Gilbert W. 1980. Sequencing end-labelled DNA with base specific chemical cleavages. Methods Enzymol. 65: 449–560.
Miller J.H. 1972. Experiments in Molecular Genetics, pp. 274–281. Cold Spring Harbor Laboratory, Cold Spring Harbor, NY.
Missiakas D., Mayer M.P., Lemaire M., Georgopoulos C. & Raina S. 1997. Modulation of the Escherichia coli σ E (RpoE) heatshock transcription-factor activity by the RseA, RseB and RseC proteins. Mol. Microbiol. 24: 355–371.
Miticka H., Rowley G., Rezuchova B., Homerova D., Humphreys S., Farn J., Roberts M. & Kormanec J. 2003. Transcriptional analysis of the rpoE gene encoding extracytoplasmatic stress response sigma factor σ E in Salmonella enterica serovar Typhimurium. FEMS Microbiol. Lett. 226: 307–314.
Raina S., Missiakas D. & Georgopoulos C. 1995. The rpoE gene encoding the σ E (σ 24) heat shock σ factor of Escherichia coli. EMBO J. 14: 1043–1055.
Rezuchova B. & Kormanec J. 2001. A two-plasmid system for identification of promoters recognized by RNA polymerase containing extracytoplasmic stress response σ E in Escherichia coli. J. Microbiol. Methods 45: 103–111.
Rezuchova B., Miticka H., Homerova D., Roberts M. & Kormanec J. 2003. New members of the Escherichia coli σ E regulon identified by a two-plasmid system. FEMS Microbiol. Lett. 225: 1–7.
Rhodius V.A., Suh W.C., Nonaka G., West J. & Gross C.A. 2006. Conserved and variable functions of the σ E stress response in related genomes. PLoS Biol. 4: e2.
Rouviere P.E., De Las Penas A., Mecsas J., Lu C.Z., Rudd K.E. & Gross C.A. 1995. rpoE, the gene encoding the second heatshock σ factor, σ E, in Escherichia coli. EMBO J. 14: 1032–1042.
Rowley G., Spector M., Kormanec J. & Roberts M. 2006. Pushing the envelope: extracytoplasmic stress response in bacterial pathogens. Nature Rev. Microbiol. 4: 383–394.
Skovierova H., Rowley G., Rezuchova B., Homerova D., Lewis C., Roberts M. & Kormanec J. 2006. Identification of the σ E regulon of Salmonella enterica serovar Typhimurium. Microbiology 152: 1347–1359.
Testerman T.L., Vazquez-Torres A., Xu Y., Jones-Carson J., Libby S.J. & Fang F.C. 2002. The alternative σ factor σ E controls antioxidant defences required for Salmonella virulence and stationary-phase survival. Mol. Microbiol. 43: 771–782.
Walsh N.P., Alba B.M., Bose B., Gross C.A. & Sauer R.T. 2003. OMP peptide signals initiate the envelope-stress response by activating DegS protease via relief of inhibition mediated by its PDZ domain. Cell 113: 61–71.
Wilken C., Kitzing K., Kurzbauer R., Ehrmann M. & Clausen T. 2004. Crystal structure of the DegS stress sensor: how a PDZ domain recognizes misfolded protein and activates a protease. Cell 117: 483–494.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Homerova, D., Rezuchova, B., Skovierova, H. et al. The expression of the rpoE operon is fine-tuned by the internal rseAp promoter in Salmonella enterica serovar Typhimurium. Biologia 65, 932–938 (2010). https://doi.org/10.2478/s11756-010-0115-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.2478/s11756-010-0115-6