An introduction to the structural organization of parasitic protozoa.

As eukaryotic cells, protozoa present a classical structural organization where most of the structures and organelles typical of mammalian cells are found. However, even for usual organelles these organisms present structural diversity. In addition, some of the protozoa structures, such as the mitochondria, peroxisomes and even the Golgi complex, are not observed. On the other hand, new organelles such as the hydrogenosomes, mitosomes, Apicoplast, kinetoplast, glycosomes (specialized peroxisomes), rhoptries, micronemes and dense granules, are characteristic features of some protozoa. Also, several unusual cytoskeletal structures, some of them made of yet uncharacterized proteins, are seen in these eukaryotic microorganisms. Further characterization of these structures indicates that they contain special enzymes involved in distinct metabolic pathways making them potential targets for the development of new anti parasite drugs.