C. parvum is an extremely hardy parasite found in water supplies throughout the world, including the United States. In persons with healthy immune systems, symptoms of infection include diarrhea, stomach cramps, upset stomach and fever. For persons with weakened immune systems, however, such as individuals with HIV/AIDS, symptoms may be more severe and can lead to serious or life-threatening illness. Because C. parvum could potentially be used as a bioterrorist agent, the NIAID has classified it as a Category B priority pathogen.
After reconstructing the predicted genes and resulting proteins of one form of C. parvum, researcher Mitchell S. Abrahamsen, Ph.D., University of Minnesota, St. Paul, MN, and his team discovered that Cryptosporidium is missing two organelles commonly found in related protozoan parasites. Gone is the apicoplast, a cellular component that provides essential metabolic functions in related parasites, including those that cause malaria and toxoplasmosis, respectively. Also absent is the mitochondrion, the so-called "energy factory" found in the cells of most plants, animals, fungi and one-celled organisms. In addition, the researchers found that Cryptosporidium has significantly fewer genes than related parasites, and, as a result, can carry out fewer metabolic functions on its own.
Because Cryptosporidium has been so difficult to study up until now--pres
Contact: Jennifer Wenger
NIH/National Institute of Allergy and Infectious Diseases