Malaria and toxoplasmosis, both potentially fatal diseases, are caused by similar parasites that
But researchers have finally solved the parasite mystery underlying how these deadly organisms can survive in different hosts to pass themselves on.
Toxoplasmosis is a disease caused bythe parasite Toxoplasma, and it is believed to be carried by about 33% of the world's dormant population. However, in people with weakened immune systems, this parasite can wake up and cause complications such as stroke and brain damage. Malaria, a mosquito-borne infectious disease, currently affects more than 200 million people and kills nearly half a million people every year, mostly children.
These parasites rely on resources to surviveavailable to their owner: in the case of Toxoplasma, these are animals and people, and in the case of malaria, also insects. This means that in order to survive, infect a host and transfer between hosts, these parasites must be flexible in creating energy, depending on what methods of obtaining energy are available to them.
Scientists have studied ATP synthase, which produces vitalimportant energy in parasites. In addition to producing energy, ATP synthase can combine into large structures that together form the mitochondrial membrane, controlling the rate of energy production and being the key to its survival. The researchers found that in these parasites, ATP synthase is capable of creating complex and unique pentagonal pyramidal structures, unlike anything produced by the same systems in the human host.
“We have made significant progress inunderstanding how the parasites that cause toxoplasmosis and malaria can adapt their energy production to the environment in which they live. This is critical to the parasite's ability to spread to different tissues and be transmitted between hosts. In addition to understanding how these parasites manage to survive and remain flexible while moving through different host environments, these results have important implications for generating knowledge that can inform drug discovery."
Dr Lilach Shaner, one of the study's lead authors from the University of Glasgow
Toxoplasmosis is usually transmitted through undercookedmeat, soil, or contact with cat feces. Although an estimated 33% of the UK population carries the inactive form of the parasite, symptoms of infection in healthy adults usually go unnoticed.
However, toxoplasmosis can be dangerous forunborn children and people with weakened immune systems, such as AIDS patients. When Toxoplasma “wakes up” in people with weakened immune systems, it can cause a stroke and, in babies, serious brain damage.
Malaria is caused by a related parasitePlasmodium, which enters humans through the bite of a mosquito. The parasite then grows in the liver and red blood cells of our blood. Parasites can also change in the blood to male and female forms, which can reinfect mosquitoes when they bite and suck on the blood of infected people.