The genus Plasmodium contains several different species that can cause different forms of malaria. As indicated above, the severest form of malaria is caused by Plasmodium falciparum. Not only does it cause a very deadly form of malaria but it is also resistant to many of the drugs used to treat people with malaria. This is a major problem.
Fortunately, this alien does have a weakness much like the extraterrestrial examples mentioned above. While multiplying and growing in the red blood cells these parasites must make their own cell membranes. They do this by producing a number of proteins that go to the surface of the red blood cell and make fatty substances called phospholipids. These phospholipids are the major constituent of the parasite's membrane. Without a cell membrane the parasites will quickly die.
One important phospholipid in the parasite's membrane is called phosphatidylcholine (PC). One building block needed in the production of PC is choline. Red blood cells that are not infected with Plasmodium do not make PC and do not use choline to make PC.
Knowing these important differences between the parasite and the humans led researchers in France, Columbia and the Netherlands to see if compounds made to mimic choline could kill Plasmodium parasites. In the February 15th, 2002, issue of Science, Kai Wengelnik and associates found that a compound they made to mimic choline called G25 will kill these parasites in a test tube and in monkeys infected with Plasmodium. They also found that even drug-resistant Plasmodium faliciparum was killed by this drug. This is truly fantastic news!
The really neat thing is that the uninfected red blood cells were not destroyed by this drug and very little drug toxicity was seen in the animals used in these studies.
They still have much work to do before this drug or one like it can be used in humans. G25 would have to be injected and that would not be too pleasant. They are working on a different form of this drug that could be taken orally. This drug may be toxic to humans and it might not kill Plasmodium that infects humans. All these studies will take several years. However, there
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