PARASITES AND PLASTIDS: BRIEF ROADMAP OF A COMPLEX RELATIONSHIP

Phylum apicomplexa form animportant group of pathogens that include manyparasitic organisms of medical and veterinaryimportance. Major members of that phylumthat are responsible for debilitating diseases in humans and animals are Toxoplasma,Plasmodium, Babesia, Theileria, Eimeria and Cryptosporidium. Lack of effective vaccines and emerging resistance against available drugs demands improved and effective new strategies for prevention and treatment of the diseases caused by these pathogens. One curious and important organelle shared by these pathogens is named as apicoplast because of its similarity to plant chloroplasts. Apicoplast is indispensable for parasites belonging to phylum apicomplexa as it provides the parasites with important metabolic intermediates. The metabolic pathways hosted by the apicoplast that provides these essential metabolites are different from the corresponding pathways in the host organisms as the apicoplast has prokaryotic origins. This makes apicoplast and its metabolic pathways important anddivergent drug targets that could be utilized to develop improved chemotherapeutic agents against apicomplexan parasites. The current review focuses on the origins of the apicoplast, the assimilation of the apicoplast after its acquirement, the chief reasons for its retention and the available drug targets against the essential cellular and metabolic pathways in the apicoplast.

Keywords: Parasites, plasmids