Biochemistry of the Coccidia

Abstract

Publisher Summary This chapter focuses on the biochemistry of the coccidia. The chapter discusses how the parasites are adapted to their particular environments, the functional significance of the parasite features, and the correlation between the ultrastructure of the parasite and its biochemistry. Coccidia contain a multitude of interesting and unusual organelles, such as those comprising the apical complex (rhoptries, micronemes, and dense granules), the feeding organelle of the intracellular stage of Cryptosporidium, the refractile bodies of Eimeria, the crystalloid body of Cryptosporidium, the plastid-like structures of Toxoplasma, Eimeria, and Sarcocystis, and the acidocalcisomes of Toxoplasma. One of the most fascinating and important aspects of coccidia is their ability to invade and grow within cells of the host but effective methods for obtaining the intracellular stages of parasites from infected animals or for growing the parasites in a host cell line in vitro have been devised only relatively recently for coccidia other than toxoplasma, and improvements are still required before some investigations will be possible. This has been and remains a major limitation on studies of most of the parasites and their interaction with their host cell.