Mutant/mutation
The mutant lacks expression of pantothenate kinase 2, putative (PANK2) and expresses GFP under the control of the strong and constitutive hsp70 promoter.

Protein (function)
The water-soluble Vitamin B5 (pantothenic acid) plays a critical role in cellular metabolism of living organisms by serving as the main precursor for the synthesis of coenzyme A (CoA). CoA is an essential cofactor for a large number of metabolic processes including fatty acid biosynthesis, cellular oxidation, and carbohydrate and amino acid metabolism. Studies in P. falciparum have shown that the parasite cannot synthesize pantothenic acid de novo and relies on the uptake of exogenous pantothenate for survival. Once transported inside the parasite, pantothenic acid is rapidly phosphorylated to form phosphopantothenate (PP) by parasite encoded pantothenate kinases. This reaction has been shown to be the rate-limiting step in CoA biosynthesis in many organisms. Phosphopantothenate is subsequently converted into CoA by four enzymes PPCS (Phosphopantothenylcysteine Synthase), PPCDC (Phosphopantothenylcysteine Decarboxylase), PPAT (Phosphopantetheine Adenylyltransferase) and DPCK (Dephospho-CoA Kinase).
Sudies in P. falciparum have indicated that pantothenic acid uptake and utilization are absolutely crucial for asexual blood stage development of the parasite within human erythrocytes. Consistent with these data, pantothenate analogs inhibit intraerythrocytic development of P. falciparum.
Other malaria parasites have been shown to use alternative routes for the synthesis or acquisition of CoA. Earlier studies in P. lophurae have shown that this avian parasite can scavenge host CoA for survival in ducks erythrocytes. Similarly, genetic studies in the murine malaria parasite P. yoelii (see RMgm-1098) have shown that parasites lacking a candidate pantothenic acid transporter undergo normal asexual development in mouse erythrocytes, suggesting the presence of an alternative route for CoA biosynthesis in this parasite or an alternative pantothenate secondary transporter.

Phenotype
Strong reduction (>70%) of ookinete formation in vivo. No oocyst and sporozoite production.

Additional information

Other mutants
RMgm-1098: a mutant lacking expression of  pantothenate transporter (PAT)
RMgm-1595: a mutant lacking expression of pantothenate kinase 1, putative (PANK1)