TABLE 1.
Enzymes and genes involved in P. falciparum sugar nucleotide biosynthesis
| Step no.a | Enzyme name | Enzyme no. | Putative P. falciparum homologuesb |
|---|---|---|---|
| 1 | Hexokinase (HK) | EC 2.7.1.1 | PF3D7_0624000 |
| 2 | Glucose-6-phosphate isomerase (G6PI) | EC 5.3.1.9 | PF3D7_1436000c |
| 3 | Glucosamine-fructose-6-phosphate aminotransferase (GFPT) | EC 2.6.1.16 | PF3D7_1025100 |
| 4 | Glucosamine-phosphate N-acetyltransferase (GNA) | EC 2.3.1.4 | No gene identifiedd |
| 5 | Phosphoacetylglucosamine mutase (PAGM) | EC 5.4.2.3 | PF3D7_1130000 |
| 6 | UDP-N-acetylglucosamine pyrophosphorylase (UAP) | EC 2.7.7.23 | PF3D7_1343600 |
| 7 | Mannose-6-phosphate isomerase (MPI) | EC 5.3.1.8 | PF3D7_0801800 |
| 8 | Phosphomannomutase (PMM) | EC 5.4.2.8 | PF3D7_1017400 |
| 9 | Mannose-1-phosphate guanyltransferase (MPG) | EC 2.7.7.13 | PF3D7_1420900 |
| 10 | GDP-mannose 4,6-dehydratase (GMD) | EC 4.2.1.47 | PF3D7_0813800 |
| 11 | GDP-l-fucose synthase (FS) | EC 1.1.1.271 | PF3D7_1014000 |
| 12 | Phosphoglucomutase (PGM) | EC 5.4.2.2 | PF3D7_1012500 |
| 13 | UTP-glucose-1-phosphate uridylyltransferase (UGP) or UDP-sugar pyrophosphorylase (USP) | EC 2.7.7.9 or EC 2.7.7.64 | PF3D7_0517500 |
| 14 | UDP-glucose 4-epimerase (GALE) | EC 5.1.3.2 | No gene identified |
| 15 | Galactokinase (GK) | EC 2.7.1.6 | No gene identified |
a Step numbers refer to those shown in Fig. 1.
b Gene ID numbers underlined are as identified and annotated in the P. falciparum genome (25, 46), and those in boldface type and underlined have been functionally characterized in this paper.
c Glucose-6-phosphate isomerase (EC 5.3.1.9) enzyme, PF3D7_1436000 has been crystallized, but to our knowledge its activity has not been published (77).