Change search
ReferencesLink to record
Permanent link

Direct link
The heat-shock protein ClpB of Francisella tularensis is involved in stress tolerance and is required for multiplication in target organs of infected mice
Show others and affiliations
2008 (English)In: Molecular Microbiology, ISSN 0950-382X, E-ISSN 1365-2958, Vol. 67, no 6, 1384-1401 p.Article in journal (Refereed) Published
Abstract [en]

Intracellular bacterial pathogens generally express chaperones such as Hsp100s during multiplication in host cells, allowing them to survive potentially hostile conditions. Francisella tularensis is a highly infectious bacterium causing the zoonotic disease tularaemia. The ability of F. tularensis to multiply and survive in macrophages is considered essential for its virulence. Although previous mutant screens in Francisella have identified the Hsp100 chaperone ClpB as important for intracellular survival, no detailed study has been performed. We demonstrate here that ClpB of F. tularensis live vaccine strain (LVS) is important for resistance to cellular stress. Promoter analysis shows that the transcriptional start is preceded by a sigma32-like promoter sequence and we demonstrate that expression of clpB is induced by heat shock. This indicates that expression of clpB is dependent on the heat-shock response mediated by sigma32, the only alternative sigma-factor present in Francisella. Our studies demonstrate that ClpB contributes to intracellular multiplication in vitro, but is not essential. However, ClpB is absolutely required for Francisella to replicate in target organs and induce disease in mice. Proteomic analysis of membrane-enriched fractions shows that five proteins are recovered at lower levels in the mutant strain. The crucial role of ClpB for in vivo persistence of Francisella may be linked to its assumed function in reactivation of aggregated proteins under in vivo stress conditions.

Place, publisher, year, edition, pages
Oxford: Blackwells , 2008. Vol. 67, no 6, 1384-1401 p.
National Category
Cell and Molecular Biology
URN: urn:nbn:se:umu:diva-20967DOI: 10.1111/j.1365-2958.2008.06139.xPubMedID: 18284578OAI: diva2:210101
Available from: 2009-03-30 Created: 2009-03-30 Last updated: 2012-09-25Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Golovliov, IgorSjöstedt, Anders
By organisation
Clinical Bacteriology
In the same journal
Molecular Microbiology
Cell and Molecular Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 43 hits
ReferencesLink to record
Permanent link

Direct link