JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 Nachin, L.
Right arrow Articles by Nyström, T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nachin, L.
Right arrow Articles by Nyström, T.
Journal of Bacteriology, September 2005, p. 6265-6272, Vol. 187, No. 18
0021-9193/05/$08.00+0     doi:10.1128/JB.187.18.6265-6272.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Differential Roles of the Universal Stress Proteins of Escherichia coli in Oxidative Stress Resistance, Adhesion, and Motility

Laurence Nachin,1 Ulf Nannmark,2 and Thomas Nyström1*

Department of Cell and Molecular Biology,1 Institute of Anatomy and Cell Biology, Göteborg University, Medicinaregatan 9C, 413 90 Göteborg, Sweden2

Received 9 March 2005/ Accepted 10 June 2005

The universal stress protein (UspA) superfamily encompasses a conserved group of proteins that are found in bacteria, archaea, and eukaryotes. Escherichia coli harbors six usp genes—uspA, -C, -D, -E, -F, and -G—the expression of which is triggered by a large variety of environmental insults. The uspA gene is important for survival during cellular growth arrest, but the exact physiological role of the Usp proteins is not known. In this work we have performed phenotypic characterization of mutants with deletions of the six different usp genes. We report on hitherto unknown functions of these genes linked to motility, adhesion, and oxidative stress resistance, and we show that usp functions are both overlapping and distinct. Both UspA and UspD are required in the defense against superoxide-generating agents, and UspD appears also important in controlling intracellular levels of iron. In contrast, UspC is not involved in stress resistance or iron metabolism but is essential, like UspE, for cellular motility. Electron microscopy demonstrates that uspC and uspE mutants are devoid of flagella. In addition, the function of the uspC and uspE genes is linked to cell adhesion, measured as FimH-mediated agglutination of yeast cells. While the UspC and UspE proteins promote motility at the expense of adhesion, the UspF and UspG proteins exhibit the exact opposite effects. We suggest that the Usp proteins have evolved different physiological functions that reprogram the cell towards defense and escape during cellular stress.


* Corresponding author. Mailing address: Department of Cell and Molecular Biology, Göteborg University, Medicinaregatan 9C, 413 90 Göteborg, Sweden. Phone: 46 31 7732582. Fax: 46 31 7732599. E-mail: thomas.nystrom{at}gmm.gu.se.


Journal of Bacteriology, September 2005, p. 6265-6272, Vol. 187, No. 18
0021-9193/05/$08.00+0     doi:10.1128/JB.187.18.6265-6272.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 2005 by the American Society for Microbiology. All rights reserved.