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
Google Scholar
Right arrow Articles by Piotrowski, A.
Right arrow Articles by Morrison, D. A.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Piotrowski, A.
Right arrow Articles by Morrison, D. A.

 Previous Article  |  Next Article 

Journal of Bacteriology, May 2009, p. 3359-3366, Vol. 191, No. 10
0021-9193/09/$08.00+0     doi:10.1128/JB.01750-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Competence for Genetic Transformation in Streptococcus pneumoniae: Termination of Activity of the Alternative Sigma Factor ComX Is Independent of Proteolysis of ComX and ComW {triangledown}

Andrew Piotrowski, Ping Luo,{dagger} and Donald A. Morrison*

Laboratory for Molecular Biology, Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607

Received 15 December 2008/ Accepted 18 February 2009

Competence for genetic transformation in Streptococcus pneumoniae is a transient physiological state whose development is coordinated by a peptide pheromone (CSP) and its receptor, which activates transcription of two downstream genes, comX and comW, and 15 other "early" genes. ComX, a transient alternative sigma factor, drives transcription of "late" genes, many of which are essential for transformation. In vivo, ComW both stabilizes ComX against proteolysis by the ClpE-ClpP protease and stimulates its activity. Interestingly, stabilization of ComX by deletion of the gene encoding the ClpP protease did not extend the period of competence. We considered the hypothesis that the rapid decay of competence arises from a rapid loss of ComW and thus of its ComX stimulating activity, so that ComX might persist but lose its transcriptional activity. Western analysis revealed that ComW is indeed a transient protein, which is also stabilized by deletion of the gene encoding the ClpP protease. However, stabilizing both ComX and ComW did not prolong either ComX activity or the period of transformation, indicating that termination of the transcriptional activity of ComX is not dependent on proteolysis of ComW.

* Corresponding author. Mailing address: LMB Room 4150, 900 South Ashland Ave., Chicago, IL 60607. Phone: (312) 996-6839. Fax: (312) 413-2691. E-mail: DAMorris{at}uic.edu

{triangledown} Published ahead of print on 13 March 2009.

{dagger} Present address: Cooperative Studies Program Coordinating Center (CSPCC), Edward Hines Jr. VA Hospital, 5000 South 5th Avenue (151K), Hines, IL 60141-3030.

Journal of Bacteriology, May 2009, p. 3359-3366, Vol. 191, No. 10
0021-9193/09/$08.00+0     doi:10.1128/JB.01750-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Piotrowski, A., Burghout, P., Morrison, D. A. (2009). spr1630 Is Responsible for the Lethality of clpX Mutations in Streptococcus pneumoniae. J. Bacteriol. 191: 4888-4895 [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»