This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Cheung, J. K.
Right arrow Articles by Rood, J. I.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Cheung, J. K.
Right arrow Articles by Rood, J. I.

 Previous Article  |  Next Article 

Journal of Bacteriology, June 2004, p. 3321-3330, Vol. 186, No. 11
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.11.3321-3330.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

The Spatial Organization of the VirR Boxes Is Critical for VirR-Mediated Expression of the Perfringolysin O Gene, pfoA, from Clostridium perfringens

Jackie K. Cheung,1 Bruno Dupuy,2 Deanna S. Deveson,1 and Julian I. Rood1*

Australian Bacterial Pathogenesis Program, Department of Microbiology, Monash University, Victoria 3800, Australia,1 Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, Paris, France2

Received 29 November 2003/ Accepted 23 February 2004

The transcriptional regulation of toxin production in the gram-positive anaerobe Clostridium perfringens involves a two-component signal transduction system that comprises the VirS sensor histidine kinase and its cognate response regulator, VirR. Previous studies showed that VirR binds independently to a pair of imperfect direct repeats, now designated VirR box 1 and VirR box 2, located immediately upstream of the promoter of the pfoA gene, which encodes the cholesterol-dependent cytolysin, perfringolysin O. For this study, we introduced mutated VirR boxes into a C. perfringens pfoA mutant and found that both VirR boxes are essential for transcriptional activation. Furthermore, the spacing between the VirR boxes and the distance between the VirR boxes and the –35 region are shown to be critical for perfringolysin O production. Other VirR boxes that were previously identified from the strain 13 genome sequence were also analyzed, with perfringolysin O production used as a reporter system. The results showed that placement of the different VirR boxes at the same position upstream of the pfoA promoter yields different levels of perfringolysin O activity. In all of these constructs, VirR was still capable of binding to the target DNA, indicating that DNA binding alone is not sufficient for transcriptional activation. Finally, we show that the C. perfringens RNA polymerase binds more efficiently to the pfoA promoter in the presence of VirR, indicating that interactions must occur between these proteins. We propose that these interactions are required for VirR-mediated transcriptional activation.

* Corresponding author. Mailing address: Australian Bacterial Pathogenesis Program, Department of Microbiology, Monash University, Victoria 3800, Australia. Phone: 61 3 9905 4825. Fax: 61 3 9905 4811. E-mail: julian.rood{at}med.monash.edu.au.

Journal of Bacteriology, June 2004, p. 3321-3330, Vol. 186, No. 11
0021-9193/04/$08.00+0     DOI: 10.1128/JB.186.11.3321-3330.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Okumura, K., Ohtani, K., Hayashi, H., Shimizu, T. (2008). Characterization of Genes Regulated Directly by the VirR/VirS System in Clostridium perfringens. J. Bacteriol. 190: 7719-7727 [Abstract] [Full Text]  
  • Crespo, R., Fisher, D. J., Shivaprasad, H.L., Fernandez-Miyakawa, M. E., Uzal, F. A. (2007). Toxinotypes of Clostridium Perfringens Isolated from Sick and Healthy Avian Species. jvdi 19: 329-333 [Abstract] [Full Text]  
  • Ross, C. L., Koehler, T. M. (2006). plcR papR-Independent Expression of Anthrolysin O by Bacillus anthracis. J. Bacteriol. 188: 7823-7829 [Abstract] [Full Text]  
  • Myers, G. S.A., Rasko, D. A., Cheung, J. K., Ravel, J., Seshadri, R., DeBoy, R. T., Ren, Q., Varga, J., Awad, M. M., Brinkac, L. M., Daugherty, S. C., Haft, D. H., Dodson, R. J., Madupu, R., Nelson, W. C., Rosovitz, M.J., Sullivan, S. A., Khouri, H., Dimitrov, G. I., Watkins, K. L., Mulligan, S., Benton, J., Radune, D., Fisher, D. J., Atkins, H. S., Hiscox, T., Jost, B. H., Billington, S. J., Songer, J. G., McClane, B. A., Titball, R. W., Rood, J. I., Melville, S. B., Paulsen, I. T. (2006). Skewed genomic variability in strains of the toxigenic bacterial pathogen, Clostridium perfringens. Genome Res 16: 1031-1040 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»