GCH1 reaction in the folate pathway of Plasmodium falciparum . Malaria parasites cannot salvage folate and need their own de novo folate pathway to synthesize folate derivatives . GCH1 converts GTP to 7,8-dihydroneopterin 3′-triphosphate, which will become the pterin moiety of folate derivatives. Several P. falciparum strains were found to contain multiple copies of gch1 (shown here as a large blue arrow). The next step in the folate pathway of P. falciparum is driven by 6-pyruvoyltetrahydropterin synthase (PTPS) to generate 6-hydroxymethyl-7,8 dihydroneopterin (HMDHP). It is worth noting that bacteria need an extra phosphorylase enzyme to remove the phosphate groups . HMDHP is activated by the addition of two phosphate groups by hydroxymethyl dihydropteridine pyrophosphokinase (HPPK). Dihydropteroate synthase (DHPS) then combines the pterin moiety with 4-aminobenzoate (pABA) to produce 7,8-dihydropteroate (DHP). The last component to be added is glutamate via the reaction driven by dihydrofolate synthase (DHFS) to form 7,8-dihydrofolate (DHF). DHF is then reduced to 5,6,7,8-tetrahydrofolate (THF) by dihydrofolate reductase (DHFR). Anti-malarial sulphadoxine (SDX) and pyrimethamine (PYR) were combined to target two enzymes in the folate pathway of malaria parasites. For the chemical detail of the malarial folate pathway, see .