Entamoeba histolytica is a eukaryotic microorganism; that is, the nuclear genetic material is enclosed within a specialized membrane. Furthermore, the microbe is a protozoan parasite. It requires a host for the completion of its life cycle, and its survival comes at the expense of the host organism. Entamoeba histolytica causes disease in humans. Indeed, after malaria and schistosomiasis, the dysentery caused by the amoeba is the third leading cause of death in the world. One-tenth of the world's population, some 500 million people, are infected by Entamoeba histolytica, with between 50,000 and 100,000 people dying of the infection each year.

The bulk of these deaths occurs in underdeveloped areas of the world, where sanitation and personal hygiene is lacking. In developed regions, where sanitation is established and where water treatment systems are in routine use, the dysentery caused by Entamoeba histolytica is almost nonexistent.

A characteristic feature of Entamoeba...