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 Seo, J.
Right arrow Articles by Darwin, A. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Seo, J.
Right arrow Articles by Darwin, A. J.

 Previous Article  |  Next Article 

Journal of Bacteriology, February 2009, p. 898-908, Vol. 191, No. 3
0021-9193/09/$08.00+0     doi:10.1128/JB.01443-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.

Analysis of Secretin-Induced Stress in Pseudomonas aeruginosa Suggests Prevention Rather than Response and Identifies a Novel Protein Involved in Secretin Function {triangledown}

Jin Seo,1 Anja Brencic,2 and Andrew J. Darwin1*

Department of Microbiology, New York University School of Medicine, New York, New York 10016,1 Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 021152

Received 14 October 2008/ Accepted 14 November 2008

Secretins are bacterial outer membrane proteins that are important for protein export. However, they can also mislocalize and cause stress to the bacterial cell, which is dealt with by the well-conserved phage shock protein (Psp) system in a highly specific manner. Nevertheless, some bacteria have secretins but no Psp system. A notable example is Pseudomonas aeruginosa, a prolific protein secretor with the potential to produce seven different secretins. We were interested in investigating how P. aeruginosa might deal with the potential for secretin-induced stress without a Psp system. Microarray analysis revealed the absence of any transcriptional response to XcpQ secretin overproduction. However, transposon insertions in either rpoN, truB, PA4068, PA4069, or PA0943 rendered P. aeruginosa hypersensitive to XcpQ production. The PA0943 gene was studied further and found to encode a soluble periplasmic protein important for XcpQ localization to the outer membrane. Consistent with this, a PA0943 null mutation reduced the levels of type 2 secretion-dependent proteins in the culture supernatant. Therefore, this work has identified a novel protein required for normal secretin function in P. aeruginosa. Taken together, all of our data suggest that P. aeruginosa lacks a functional equivalent of the Psp stress response system. Rather, null mutations in genes such as PA0943 may cause increased secretin-induced stress to which P. aeruginosa cannot respond. Providing the PA0943 mutant with the ability to respond, in the form of critical Psp proteins from another species, alleviated its secretin sensitivity.


* Corresponding author. Mailing address: Department of Microbiology MSB 228, New York University School of Medicine, 550 First Avenue, New York, NY 10016. Phone: (212) 263-3223. Fax: (212) 263-8276. E-mail: andrew.darwin{at}med.nyu.edu

{triangledown} Published ahead of print on 21 November 2008.


Journal of Bacteriology, February 2009, p. 898-908, Vol. 191, No. 3
0021-9193/09/$08.00+0     doi:10.1128/JB.01443-08
Copyright © 2009, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Viarre, V., Cascales, E., Ball, G., Michel, G. P. F., Filloux, A., Voulhoux, R. (2009). HxcQ Liposecretin Is Self-piloted to the Outer Membrane by Its N-terminal Lipid Anchor. J. Biol. Chem. 284: 33815-33823 [Abstract] [Full Text]