This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Amino Acids Biosynthesis → Proteinogenic Amino Acids Biosynthesis → L-glutamate Biosynthesis|
Some taxa known to possess this pathway include : Homo sapiens
Glutamate is biosynthesized in the mitochondrion from the tricarboxylic acid (TCA) cycle intermediate α-ketoglutarate. As shown in this pathway, glutamate dehydrogenase NAD(P)+ produces glutamate by reductive amination of α-ketoglutarate with ammonia. Glutamate is a precursor of proline, ornithine, arginine and glutamine [Salway04a, Voet04].
Other reactions of glutamate biosynthesis are also found. In bacteria, glutamate dehydrogenase and glutamate synthase are both involved in ammonia assimilation. Glutamate synthase (NADPH) (see pathway L-glutamate biosynthesis I) is widespread in bacteria and is utilized at low concentrations of ammonia. Glutamate dehydrogenase (NADP+) (see pathway L-glutamate biosynthesis III) does not appear to operate when ammonia is scarce [Gottschalk86]. In fungi and plants, glutamate synthase (NADH) is also involved in ammonia assimilation (see pathway L-glutamate biosynthesis IV). Plants and cyanobacteria [Navarro00] can use a ferredoxin-dependent glutamate synthase (see pathway L-glutamate biosynthesis V).
Superpathways: L-glutamate and L-glutamine biosynthesis
Navarro00: Navarro F, Martin-Figueroa E, Candau P, Florencio FJ (2000). "Ferredoxin-dependent iron-sulfur flavoprotein glutamate synthase (GlsF) from the Cyanobacterium synechocystis sp. PCC 6803: expression and assembly in Escherichia coli." Arch Biochem Biophys 379(2);267-76. PMID: 10898944
Fang02: Fang J, Hsu BY, MacMullen CM, Poncz M, Smith TJ, Stanley CA (2002). "Expression, purification and characterization of human glutamate dehydrogenase (GDH) allosteric regulatory mutations." Biochem J 363(Pt 1);81-7. PMID: 11903050
Hussain89: Hussain MM, Zannis VI, Plaitakis A (1989). "Characterization of glutamate dehydrogenase isoproteins purified from the cerebellum of normal subjects and patients with degenerative neurological disorders, and from human neoplastic cell lines." J Biol Chem 264(34);20730-5. PMID: 2573605
Julliard78: Julliard JH, Crastes de Paulet A (1978). "Human placental glutamate dehydrogenase. Purification--kinetic and regulatory properties--physicochemical studies." Biochimie 60(11-12);1329-32. PMID: 753382
Kort97: Kort R, Liebl W, Labedan B, Forterre P, Eggen RI, de Vos WM (1997). "Glutamate dehydrogenase from the hyperthermophilic bacterium Thermotoga maritima: molecular characterization and phylogenetic implications." Extremophiles 1997;1(1);52-60. PMID: 9680336
Lebbink98: Lebbink JH, Knapp S, van der Oost J, Rice D, Ladenstein R, de Vos WM (1998). "Engineering activity and stability of Thermotoga maritima glutamate dehydrogenase. I. Introduction of a six-residue ion-pair network in the hinge region." J Mol Biol 1998;280(2);287-96. PMID: 9654452
Lebbink99: Lebbink JH, Knapp S, van der Oost J, Rice D, Ladenstein R, de Vos WM (1999). "Engineering activity and stability of Thermotoga maritima glutamate dehydrogenase. II: construction of a 16-residue ion-pair network at the subunit interface." J Mol Biol 1999;289(2);357-69. PMID: 10366510
Michaelidis93: Michaelidis TM, Tzimagiorgis G, Moschonas NK, Papamatheakis J (1993). "The human glutamate dehydrogenase gene family: gene organization and structural characterization." Genomics 16(1);150-60. PMID: 8486350
Shashidharan94: Shashidharan P, Michaelidis TM, Robakis NK, Kresovali A, Papamatheakis J, Plaitakis A (1994). "Novel human glutamate dehydrogenase expressed in neural and testicular tissues and encoded by an X-linked intronless gene." J Biol Chem 269(24);16971-6. PMID: 8207021
Tanizawa02: Tanizawa Y, Nakai K, Sasaki T, Anno T, Ohta Y, Inoue H, Matsuo K, Koga M, Furukawa S, Oka Y (2002). "Unregulated elevation of glutamate dehydrogenase activity induces glutamine-stimulated insulin secretion: identification and characterization of a GLUD1 gene mutation and insulin secretion studies with MIN6 cells overexpressing the mutant glutamate dehydrogenase." Diabetes 51(3);712-7. PMID: 11872671
Zaganas02: Zaganas I, Plaitakis A (2002). "Single amino acid substitution (G456A) in the vicinity of the GTP binding domain of human housekeeping glutamate dehydrogenase markedly attenuates GTP inhibition and abolishes the cooperative behavior of the enzyme." J Biol Chem 277(29);26422-8. PMID: 11950837
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