Metabolic pathways in the apicoplast of apicomplexa

Abstract

Intracellular parasites of the phylum Apicomplexa harbor a plastid-like organelle called apicoplast that is the most reduced organelle of this type known. Due to the medical importance of some members of Apicomplexa, a number of fully sequenced genomes are available that have allowed to assemble metabolic pathways also from the apicoplast and have revealed initial clues to its essential nature for parasite survival in the host. We provide a compilation of Internet resources useful to access, reconstruct, verify, or annotate metabolic pathways. Then we show detailed and updated metabolic maps and discuss the three major biosynthetic pathways leading to the generation of isoprenoids, fatty acids, and heme, and compare these routes in the different species. Moreover, several auxiliary pathways, like iron-sulfur cluster assembly, are covered and put into context with the major metabolic routes. Finally, we highlight some aspects that emerged from recent publications and were not discussed previously with regard to Apicomplexa.