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 Bernadac, A.
Right arrow Articles by Lloubès, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bernadac, A.
Right arrow Articles by Lloubès, R.

Journal of Bacteriology, September 1998, p. 4872-4878, Vol. 180, No. 18
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Escherichia coli tol-pal Mutants Form Outer Membrane Vesicles

Alain Bernadac,1 Marthe Gavioli,1 Jean-Claude Lazzaroni,2 Satish Raina,3 and Roland Lloubès1,*

Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UPR 9027, CNRS, Institut de Biologie Structurale et Microbiologie, 13402 Marseille Cedex 20,1 and Laboratoire de Microbiologie et Génétique Moléculaire, UMR 5534, CNRS-Université Lyon 1, 69622 Villeurbanne Cedex,2 France, and Département de Biochimie Médicale, Centre Médical Universitaire, Geneva 4, Switzerland3

Received 9 March 1998/Accepted 7 July 1998

Mutations in the tol-pal genes induce pleiotropic effects such as release of periplasmic proteins into the extracellular medium and hypersensitivity to drugs and detergents. Other outer membrane defective strains such as tolC, lpp, and rfa mutations are also altered in their outer membrane permeability. In this study, electron microscopy and Western blot analyses were used to show that strains with mutations in each of the tol-pal genes formed outer membrane vesicles after growth in standard liquid or solid media. This phenotype was not observed in tolC and rfaD cells in the same conditions. A tolA deletion in three different Escherichia coli strains was shown to lead to elevated amounts of vesicles. These results, together with plasmid complementation experiments, indicated that the formation of vesicles resulted from the defect of any of the Tol-Pal proteins. The vesicles contained outer membrane trimeric porins correctly exposed at the cell surface. Pal outer membrane lipoprotein was also immunodetected in the vesicle fraction of tol strains. The results are discussed in view of the role of the Tol-Pal transenvelope proteins in maintaining outer membrane integrity by contributing to target or integrate newly synthesized components of this structure.

* Corresponding author. Mailing address: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UPR 9027, CNRS, Institut de Biologie Structurale et Microbiologie 13402 Marseille Cedex 20, France. Phone: 33-4-91-76-03-59. Fax: 33-4-91-71-21-24. E-mail: lloubes{at}ibsm.cnrs-mrs.fr.

Journal of Bacteriology, September 1998, p. 4872-4878, Vol. 180, No. 18
0021-9193/98/$04.00+0
Copyright © 1998, 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 © 1998 by the American Society for Microbiology. All rights reserved.