AEM
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 Hundt, M. J.
Right arrow Articles by Ruffolo, C. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hundt, M. J.
Right arrow Articles by Ruffolo, C. G.
Agricola
Right arrow Articles by Hundt, M. J.
Right arrow Articles by Ruffolo, C. G.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, September 2005, p. 5458-5464, Vol. 71, No. 9
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.9.5458-5464.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Interaction of Pasteurella multocida with Free-Living Amoebae

Matthew J. Hundt and Carmel G. Ruffolo*

Department of Biological Sciences, University of Wisconsin—Parkside, Kenosha, Wisconsin

Received 16 November 2004/ Accepted 23 March 2005

Pasteurella multocida is a highly infectious, facultative intracellular bacterium which causes fowl cholera in birds. This study reports, for the first time, the observed interaction between P. multocida and free-living amoebae. Amoebal trophozoites were coinfected with fowl-cholera-causing P. multocida strain X-73 that expressed the green fluorescent protein (GFP). Using confocal fluorescence microscopy, GFP expressing X-73 was located within the trophozoite. Transmission electron microscopy of coinfection preparations revealed clusters of intact X-73 cells in membrane-bound vacuoles within the trophozoite cytoplasm. A coinfection assay employing gentamicin to kill extracellular bacteria was used to assess the survival and replication of P. multocida within amoebae. In the presence of amoebae, the number of recoverable intracellular X-73 cells increased over a 24-h period; in contrast, X-73 cultured alone in assay medium showed a consistent decline in growth. Cytotoxicity assays and microscopy showed that X-73 was able to lyse and exit the amoebal cells approximately 18 h after coinfection. The observed interaction between P. multocida and amoebae can be considered as an infective process as the bacterium was able to invade, survive, replicate, and lyse the amoebal host. This raises the possibility that similar interactions occur in vivo between P. multocida and host cells. Free-living amoebae are ubiquitous within water and soil environments, and P. multocida has been observed to survive within these same ecosystems. Thus, our findings suggest that the interaction between P. multocida and amoebae may occur within the natural environment.

* Corresponding author. Mailing address: Department of Biological Sciences, University of Wisconsin—Parkside, P. O. Box 2000, Kenosha, WI 53144. Phone: (262) 595-2174. Fax: (262) 595-2056. E-mail: carmel.ruffolo{at}uwp.edu.

Applied and Environmental Microbiology, September 2005, p. 5458-5464, Vol. 71, No. 9
0099-2240/05/$08.00+0     doi:10.1128/AEM.71.9.5458-5464.2005
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]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

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