Glutamate metabolism

Glutamate and glutamine are non-essential amino acids in both Toxoplasma gondii and Plasmodium falciparum as in humans. Both organisms possess NAD+-specific ( and NADP+-specific (, 2 isoforms in P. falciparum and 1 in T. gondii) glutamate dehydrogenases that catalyse reversible conversion of glutamate to 2-oxoglutarate. The metabolic pathway in MPMP ( is extended here for Toxoplasma as it possesses the capability to de novo synthesise proline from glutamate as in humans [1]. The genes for all the enzymes involved in this process are present in T. gondii gene models. The genes encoding the enzymes glutamate 5-kinase and glutamyl phosphate reductase are absent in P. falciparum genome.


Enzyme EC Number Gene id Protein localisation Localisation data source
Glutamate-5-semialdehyde dehydrogenase TGME49_270550 Cytosol Previous publication
Glutamate dehydrogenase TGME49_249390 Mitochondrion Previous publication
Glutamate dehydrogenase TGME49_293180 Cytosol Previous publication
Pyrroline-5-carboxylate reductase TGME49_236070 Extracellular? Previous publication
Pyrroline-5-carboxylate reductase TGME49_271610 Apicoplast Previous publication
Glutaminyl-peptide cyclotransferase TGME49_258020    
Aspartate transaminase TGME49_248600 Cytosol Previous publication
Hexosephosphate aminotransferase TGME49_231350 Apicoplast Previous publication
Glutamate 5-kinase TGME49_265010    
Glutamyl-tRNA synthetase TGME49_241870    
Glutamyl-tRNA synthetase TGME49_263870 Cytosol Previous publication
Glutaminyl-tRNA synthetase TGME49_217460 Cytosol; Mitochondrion Apiloc; Previous publication
L-glutamate ammonia ligase TGME49_273490 Cytosol Previous publication
gamma-Glutamylcysteine synthetase TGME49_232590    
Carbamoyl-phosphate synthase Glu synthesizing TGME49_215260 Cytosol Previous publication
Glutamyl-tRNA(Gln) amidotransferase TGME49_233838    


List of genes annotated as tRNA-Glu in T. gondii genome


TGME49_002320 TGME49_014360 TGME49_018480 TGME49_034622
TGME49_061550 TGME49_068440 TGME49_068450 TGME49_071891
TGME49_111190 TGME49_111200    


List of genes annotated as tRNA-Gln in T. gondii genome


TGME49_034617 TGME49_067110 TGME49_072220 TGME49_075820
TGME49_102030 TGME49_105170 TGME49_115200  


Open in a new window



Sources and fates of metabolites


Substrate Source pathways Product Fate pathways
D-Fructose-6P Glycolysis Oxaloacetate Pyruvate metabolism, Tricarboxylic acid (TCA) cycle
    2-oxoglutarate Tricarboxylic acid (TCA) cycle
    gamma-glutamylcysteine Redox metabolism
    Glucosamine-6P Aminosugars metabolism
    Carbamoyl-P Pyrimidine metabolism
    L-Proline Proline metabolism