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 Castelli, M. E.
Right arrow Articles by Véscovi, E. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Castelli, M. E.
Right arrow Articles by Véscovi, E. G.

 Previous Article  |  Next Article 

Journal of Bacteriology, January 2008, p. 213-220, Vol. 190, No. 1
0021-9193/08/$08.00+0     doi:10.1128/JB.01348-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Enterobacterial Common Antigen Integrity Is a Checkpoint for Flagellar Biogenesis in Serratia marcescens{triangledown}

María E. Castelli,1 Griselda V. Fedrigo,1 Ana L. Clementín,1 M. Verónica Ielmini,2 Mario F. Feldman,2 and Eleonora García Véscovi1*

Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina,1 Department of Biological Sciences, University of Alberta, T6G 2E9 Edmonton, Alberta, Canada2

Received 17 August 2007/ Accepted 23 October 2007

Serratia marcescens strains are ubiquitous bacteria isolated from environmental niches, such as soil, water, and air, and also constitute emergent nosocomial opportunistic pathogens. Among the numerous extracellular factors that S. marcescens is able to produce, the PhlA phospholipase is the only described exoprotein secreted by the flagellar apparatus while simultaneously being a member of the flagellar regulon. To gain insight into the regulatory mechanism that couples PhlA and flagellar expression, we conducted a generalized insertional mutagenesis and screened for PhlA-deficient strains. We found that three independent mutations in the wec cluster, which impaired the assembly of enterobacterial common antigen (ECA), provoked the inhibition of PhlA expression. Swimming and swarming assays showed that in these strains, motility was severely affected. Microscopic examination and flagellin immunodetection demonstrated that a strong defect in flagellum expression was responsible for the reduced motility in the wec mutant strains. Furthermore, we determined that in the ECA-defective strains, the transcriptional cascade that controls flagellar assembly was turned off due to the down-regulation of flhDC expression. These findings provide a new perspective on the physiological role of the ECA, providing evidence that in S. marcescens, its biosynthesis conditions the expression of the flagellar regulon.

* Corresponding author. Mailing address: Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina. Phone: 54-341-4356369. Fax: 54-341-4804598. E-mail: garciavescovi{at}ibr.gov.ar

{triangledown} Published ahead of print on 2 November 2007.

Journal of Bacteriology, January 2008, p. 213-220, Vol. 190, No. 1
0021-9193/08/$08.00+0     doi:10.1128/JB.01348-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Barchiesi, J., Castelli, M. E., Soncini, F. C., Vescovi, E. G. (2008). mgtA Expression Is Induced by Rob Overexpression and Mediates a Salmonella enterica Resistance Phenotype. J. Bacteriol. 190: 4951-4958 [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»