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Prion protein degradation by lichens of the genus Cladonia

  • James P. BENNETT (a1) (a2), Cynthia M. RODRIGUEZ (a1) (a3) and Christopher J. JOHNSON (a1)

It has recently been discovered that lichens contain a serine protease capable of degrading the pathogenic prion protein, the etiological agent of prion diseases such as sheep scrapie and cervid chronic wasting disease. Limited methods are available to degrade or inactivate prion disease agents, especially in the environment, and lichens or their serine protease could prove important for management of these diseases. Scant information is available regarding the presence or absence of the protease responsible for degrading prion protein (PrP) in lichen species and, in this study, we tested the hypothesis that PrP degradation activity in lichens is phylogenetically-based by testing 44 species of Cladonia lichens, a genus for which a significant portion of the phylogeny is well established. We categorized PrP degradation activity among the 44 species (high, moderate, low or none) and found that activity in Cladonia species did not correspond with phylogenetic position of the species. Degradation of PrP did correspond, however, with three classical taxonomic characters within the genus: species with brown apothecia, no usnic acid, and the presence of a cortex. Of the 44 species studied, 18 (41%) had either high or moderate PrP degradation activity, suggesting the protease may be frequent in this genus of lichens.

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Ahti, T. & Hammer, S. (2002) Cladonia. In Lichen Flora of the Greater Sonoran Desert Region. Vol. 1 (Nash, T. H. III, Ryan, B. D., Gries, C. & Bungartz, F., eds): 131158. Tempe, Arizona: Lichens Unlimited.
Brodo, I. M., Sharnoff, S. D. & Sharnoff, S. (2001) Lichens of North America. New Haven and London: Yale University Press.
Colby, D. W. & Prusiner, S. B. (2011) Prions. Cold Spring Harbor Perspectives in Biology 3: a006833.
Detwiler, L. A. (2003) The epidemiology of scrapie. Scientific and Technical Review 22: 121143.
Esslinger, T. L. (2011) A cumulative checklist for the lichen-forming, lichenicolous and allied fungi of the continental United States and Canada. North Dakota State University: (First Posted 1 December 1997, Most Recent Version (#17) accessed 16 May 2011), Fargo, North Dakota.
Gough, K. C. & Maddison, B. C. (2010) Prion transmission: prion excretion and occurrence in the environment. Prion 4: 275282.
Guo, S. & Kashiwadani, H. (2004) Recent study on the phylogeny of the genus Cladonia (s. lat.) with the emphasis on the integrative biology. National Science Museum Monographs 24: 207225.
Hinds, J. W. & Hinds, P. L. (2007) The Macrolichens of New England. New York: New York Botanical Garden Press.
Johnson, C. J., Bennett, J. P., Biro, S. M., Duqu-Velaszuez, J. C., Rodriguez, C. M., Bessen, R. A. & Rocke, T. E. (2011) Degradation of the disease-associated prion protein by a serine protease from lichens. PLoS ONE 6: e19836.
Legaz, M-E., Fontaniella, B., Millanes, A-M. & Vicente, C. (2004) Secreted arginases from phylogenetically far-related lichen species act as cross-recognition factors for two different algal cells. European Journal of Cell Biology 83: 435446.
Lendemer, J. C. & Hodkinson, B. P. (2009) The wisdom of fools: new molecular and morphological insights into the North American apodetiate species of Cladonia. Opuscula Philolichenum 7: 79100.
North, M. J. (1982) Comparative biochemistry of the proteinases of eukaryotic microorganisms. Microbiological Reviews 46: 308340.
Piercey-Normore, M. D. & DePriest, P. T. (2001) Algal switching among lichen symbioses. American Journal of Botany 88: 14901498.
Rodriguez, C. M., Bennett, J. P. & Johnson, C. J. (2012) Lichens: unexpected anti-prion agents? Prion 6: 16.
SAS Institute. (2009) JMP Statistical Discovery Software. Cary, North Carolina: SAS Institute, Inc..
Sigurdson, C. J. (2008) A prion disease of cervids: chronic wasting disease. Veterinary Research 39: 41.
Smith, C. B., Booth, C. J. & Pedersen, J. A. (2011) Fate of prions in soil: a review. Journal of Environmental Quality 40: 449461.
Stenroos, S., Hyvönen, J., Myllys, L., Thell, A. & Ahti, T. (2002) Phylogeny of the genus Cladonia s. lat. (Cladoniaceae, Ascomycetes) inferred from molecular, morphological and chemical data. Cladistics 18: 237278.
Taylor, D. M. (2000) Inactivation of transmissible degenerative encephalopathy agents: a review. The Veterinary Journal 159: 1017.
Thomson, J. W. (1967) The Lichen Genus Cladonia in North America. Toronto: University of Toronto Press.
Watts, J. C., Balachandran, A. & Westaway, D. (2006) The expanding universe of prion diseases. PLoS Pathogens 2: e26.
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The Lichenologist
  • ISSN: 0024-2829
  • EISSN: 1096-1135
  • URL: /core/journals/lichenologist
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