Plasmodium falciparum Apicomplexan-Specific Glucosamine-6-Phosphate -Acetyltransferase Is Key for Amino Sugar Metabolism and Asexual Blood Stage Development.

UDP--acetylglucosamine (UDP-GlcNAc), the main product of the hexosamine biosynthetic pathway, is an important metabolite in protozoan parasites since its sugar moiety is incorporated into glycosylphosphatidylinositol (GPI) glycolipids and - and -linked glycans. Apicomplexan parasites have a hexosamine pathway comparable to other eukaryotic organisms, with the exception of the glucosamine-phosphate -acetyltransferase (GNA1) enzymatic step that has an independent evolutionary origin and significant differences from nonapicomplexan GNA1s. By using conditional genetic engineering, we demonstrate the requirement of GNA1 for the generation of a pool of UDP-GlcNAc and for the development of intraerythrocytic asexual parasites.