Claviceps purpurea
Classification
Fungi; Ascomycota; Sordariomycetes; Hypocreales; Ckavucuoutaceae [Others may be used. Use NCBI link to find]
Species
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NCBI: [1] |
'Claviceps purpurea' Common Name: rye ergot fungus 'Italic text' Anamorph: Sphacelia segetum''
Description and Significance
The fungus Claviceps purpurea is responsible for causing the fungal disease ergot of rye. Of the approximate 40 species of Claviceps described, C. purpurea is of the most importance due to its potential economic loss in rye crops and its significant toxicity to both humans and animals. C. purpurea has been known to infect over 400 grass and cereal species and can found in temperate regions around the world. Though the loss of crops due to ergot is typically low, only 5-10%, the health affects that consumption can have on humans can be severe. In historical accounts, Ergotism, which is the disease caused by consumption of contaminated plants, caused hallucinations, fever, convulsions, loss of fertility, miscarriage, and loss of limbs in humans. Due to modern management strategies, the risk of exposure to ergotism today is low in comparison to historical times. Today, compounds isolated from Clavicepshave been used to create medicines to treat migraine headaches, heavy menstrual bleeding, bleeding after child-birth, and neurological and cardiovascular disorders.
Life Cycle, Cell Structure, Metabolism
Interesting features of the life cycle, spores produced, reproductive features; how it gains energy; what important molecules it produces. C. purpurea is unique in that it only infects ovaries in typically young, unfertilized plants. Ascospores are dispersed by wind and land on plant stigma alongside pollen grains. These spores infect the ovary where hyphae begin to develop. Following hyphal development, conidia are formed and dispersed with the help of insects who are attracted to a sticky substance created by a combination of fungal conidia and sap from the host plant called honeydew. The infected plant ovary is then replaced by sclerotia, or ergot, which consists of hardened mycelia used for protection, dormancy, and survival . When the crop is harvested, the sclerotia makes its way in with the grain, leading to contamination of the harvest. Contamination comes from alkaloids present in the sclerotia, which are categorized into three groups: clavines, ergopeptines, and amides of lysergic acid, the latter being a derivative used to produce LSD.
Genome Structure
Describe the size and content of the genome. How many chromosomes? Other interesting features? What is known about its sequence?
Ecology and Pathogenesis
Habitat; symbiosis; environmental or industrial relevance; contributions to environment.
If relevant, how does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as host symptoms.
References
Author
Page authored by Gayle J. Nance, student of Dr. Marc Orbach, University of Arizona .
