Amoeba Provide Insight into the Origin of Virulence in Pathogenic Fungi

  • Arturo Casadevall
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 710)


Why are some fungi pathogenic while the majority poses no threat to humans or other hosts? Of the more than 1.5 million fungal species only about 150–300 are pathogenic for humans, and of these, only 10–15 are relatively common pathogens. In contrast, fungi are major pathogens for plants and insects. These facts pose several fundamental questions including the mechanisms responsible for the origin of virulence among the few pathogenic species and the high resistance of mammals to fungal diseases. This essay explores the origin of virulences among environmental fungi with no obvious requirement for animal association and proposes that selection pressures by amoeboid predators led to the emergence of traits that can also promote survival in mammalian hosts. In this regard, analysis of the interactions between the human pathogenic funges Cryptococcus neoformans and amoeba have shown a remarkable similarity with the interaction of this fungus with macrophages. Hence the virulence of environmental pathogenic fungi is proposed to originate from a combination of selection by amoeboid predators and perhaps other soil organism with thermal tolerance sufficient to allow survival in mammalian hosts


Mammalian Host Systemic Mycosis Tinea Pedis Human Pathogenic Fungus Saccharomyces Boulardii 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Departments of Microbiology and Immunology and Medicine (Division of Infectious Diseases)Albert Einstein College of MedicineBronxUSA

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