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Intracellular pathogenic bacteria and fungi — a case of convergent evolution?

Nature Reviews Microbiology volume 7, pages 165–171 (2009)Cite this article

Abstract

The bacterium Yersinia pestis and the fungus Cryptococcus neoformans are the causative agents of human plague and cryptococcosis, respectively. Both microorganisms are facultatively intracellular pathogens. A comparison of their pathogenic strategies reveals similar tactics for intracellular survival in Y. pestis and C. neoformans despite their genetic unrelatedness. Both organisms can survive in environments where they are vulnerable to predation by amoeboid protozoal hosts. Here, we propose that the overall similarities in their pathogenic strategies are an example of convergent evolution that has solved the problem of intracellular survival.

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Figure 1: Model for the interaction of Yersinia pestis with macrophages.
Figure 2: Model for the interaction of Cryptococcus neoformans with macrophages.

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Acknowledgements

Work in the laboratory of J.B.B. on intracellular replication of Y. pestis in macrophages is supported by Public Health Service (PHS) grant AI055621. Work in the laboratory of A.C. on intracellular pathogenesis of C. neoformans is supported by PHS grant HL59842-11. A.C. and J.B.B. both contribute research to, and receive support from, the Northeastern Biodefense Center (grant number 5U54AI057158-05). The authors thank C. Pujol and M. Alvarez for providing the electron-microscopy images used in the figures and for reviewing the manuscript.

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Authors and Affiliations

  1. James B. Bliska is at the Department of Molecular Genetics and Microbiology and Center for Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, New York, 11794 New York, USA.,

    James B. Bliska

  2. Arturo Casadevall is at the Departments of Microbiology & Immunology and the Division of Infectious Diseases of the Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, 10461 New York, USA.,

    Arturo Casadevall

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Correspondence to Arturo Casadevall.

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DATABASES

Entrez Genome Project

Cryptococcus neoformans

Francisella tularensis

Histoplasma capsulatu m

Legionella pneumophila

Mycobacterium tuberculosis

S. Typhimurium

Toxoplasma gondii

Yersinia pestis

Yersinia pseudotuberculosis

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Arturo Casadevall's homepage

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Bliska, J., Casadevall, A. Intracellular pathogenic bacteria and fungi — a case of convergent evolution?. Nat Rev Microbiol 7, 165–171 (2009). https://doi.org/10.1038/nrmicro2049

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