1887

Chapter 27 : Protozoa and Lurking Pathogens

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Ebook: Choose a downloadable PDF or ePub file. Chapter is a downloadable PDF file. File must be downloaded within 48 hours of purchase

Buy this Chapter
Digital (?) $7.00

Preview this chapter:
Zoom in
Zoomout

Protozoa and Lurking Pathogens, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555817442/9781555815004_Chap27-1.gif /docserver/preview/fulltext/10.1128/9781555817442/9781555815004_Chap27-2.gif

Abstract:

Michael Brown believes that while protozoal grazing of bacteria is well recognized, people have neglected a very different scenario in other environments. Here, bacteria invade protozoa, replicate, and emerge better fitted to enter other protozoa, as well as more resistant to antibiotics, biocides, and other stresses. One can envisage the two forms of microbial life coexisting and coevolving before we and other animals appeared. The principal selective factors affecting bacteria were predation by protozoa and environmental stresses, such as drying, freezing, and oxidation. A major plank in Brown's hypothesis is the significance of protozoa today as reservoirs of animal (including human) pathogens. Brown cites two examples of the possible medical relevance of the discoveries. Grazing cattle almost certainly ingest protozoa in silage and grass, so if the protozoa contain pathogens, this could be a significant route of infection between and within cattle herds. The link proposed by Brown between bacterial evolution in the environment and pathogenicity is the general stress response (GSR). Building on evidence of its dual role in survival and virulence, he argues that the coevolution of bacteria and protozoa equipped some species of bacteria both for persistence in the environment and for invasion of, and survival in, animal cells. Commenting on the apparent decline in infection in developed countries, Martin Blaser has argued that “to maintain its niche in the human biosphere, must be transmitted from person to person."

Citation: Dixon B. 2009. Protozoa and Lurking Pathogens, p 122-125. In Animalcules. ASM Press, Washington, DC. doi: 10.1128/9781555817442.ch27

Key Concept Ranking

Peyer's Patches
0.49980757
General Stress Response
0.44154012
Helicobacter pylori
0.4165063
Escherichia coli
0.40262273
0.49980757
Highlighted Text: Show | Hide
Loading full text...

Full text loading...

References

/content/book/10.1128/9781555817442.chap27
1. Barker, J.,, T. J. Humphrey,, and M. W. Brown. 1999. Survival of Escherichia coli O157 in a soil protozoan: implications for disease. FEMS Microbiol. Lett. 173:291295.
2. Blaser, M. J. 1999. Where does Helicobacter pylori come from and why is it going away? JAMA 282:22602262.
3. Cirillo, J. D.,, S. Falkow,, and L. S. Tompkins. 1994. Growth of Legionella pneumphila in Acanthamoeba castellanii enhances invasion. Infect. Immun. 62:32543261.
4. Cirillo, J. D.,, S. Falkow,, L. S. Tompkins,, and L. E. Bermudez. 1997. Interaction of Mycobacterium avium with environmental amoebae enhances virulence. Infect. Immun. 65:37593767.

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error