Glutamic decarboxylase

Pyridoxamine phosphate serves as a coenzyme of transaminases, e.g., lysyl oxidase (collagen biosynthesis), serine hydroxymethyl transferase (Cl-metabolism), S-aminolevulinate synthase (porphyrin biosynthesis), glycogen phosphoiylase (mobilization of glycogen), aspartate aminotransferase (transamination), alanine aminotransferase (transamination), kynureninase (biosynthesis of niacin), glutamate decarboxylase (biosynthesis of GABA), tyrosine decarboxylase (biosynthesis of tyramine), serine dehydratase ((3-elimination), cystathionine 3-synthase (metabolism of methionine), and cystathionine y-lyase (y-elimination). 

Jung H, Toth PT, White PA, Miller RJ (2008) Monocyte chemoattractant protein-1 functions as a neuromodulator in dorsal root ganglia neurons. J Neurochem 104 254-263 Kahn L, Alonso G, Normand E, Manzoni OJ (2005) Repeated morphine treatment alters polysia-lylated neural cell adhesion molecule, glutamate decarboxylase-67 expression and ceU proliferation in the adult rat hippocampus. Em J Nemosci 21 493-500 Kaul M, Ma Q, Medders KE, Desai MK, Lipton SA (2007) HIV-1 coreceptors CCR5 and CXCR4 both mediate neuronal cell death but CCR5 paradoxically can also contribute to protection. Cell Death Differ (2) 296-305... 

Erlander, MG, Tillakaratne, NJ, Feldblum, S, Patel, N and Tobin, AJ (1991) Two genes encode distinct glutamate decarboxylases. Neuron 7 91-100. 

Hsu, CC, Thomas, C, Chen, W, Davis, KM, Foos, T, Chen, JL, Wu, E, Floor, E, Schloss, JV and Wu, JY (1999) Role of synaptic vesicle proton gradient and protein phosphorylation on ATP-mediated activation of membrane-associated brain glutamate decarboxylase. J. Biol. Chem. 274 24366-24371. 

Obata, K, Fukuda, T, Konishi, S, Ji, FY, Mitoma, H and Kosaka, T (1999) Synaptic localization of the 67,000 mol. wt isoform of glutamate decarboxylase and transmitter function of GABA in the mouse cerebellum lacking the 65,000 mol. wt isoform. Neuroscience 93 1475-1482. 

Hotchkiss, A.J. Morgan, M.E. and Gibb, J.W. The long-term effects of multiple doses of methamphetamine on neostriatal tryptophan hydroxylase, tyrosine hydroxylase, choline acetyltransferase and glutamate decarboxylase activities. Life Sci 25 1373-1378. 1979. 

Congenital defects in the metabolism of y-aminobutyric acid have been described. GABA is formed via the action of glutamate decarboxylase (see Ch. 16). Metabolism of this neurotransmitter is mediated first by uptake into... 

Pyridoxine dependency. Pyridoxine dependency is characterized by severe seizure activity of early onset, perhaps even in utero. Patients respond dramatically to parenteral administration of pyridoxine (10-100 mg). Speculation has centered on the possibility that the disease involves faulty binding of pyridoxine, a cofactor in the glutamate decarboxylase reaction, to the enzyme protein. 

Glutamate decarboxylase 4.1.1.15 L-Glutamate 4-Aminobutyrate/C02 Carbon dioxide electrode... 

The rate of synthesis of this transmitter is determined by glutamate decarboxylase, which synthesizes it from glutamate. A feedback inhibitory mechanism also seems to operate whereby an excess of GABA in the... 

For reactions in which one or more reactants or products is a gas, manometry (the measurement of pressure differences) can provide a convenient means for monitoring the course and kinetics of the reaction Thus, enzymes that can be assayed with this method include oxidases, urease, carbonic anhydrase, hydrogenase, and decarboxylases. For example, bacterial glutamate decarboxylase is readily assayed by utilizing a Warburg flask and measuring the volume of gas evolved at different times using a constant-pressure respirometer. ... 

PLP-dependent enzymes catalyze the following types of reactions (1) loss of the ce-hydrogen as a proton, resulting in racemization (example alanine racemase), cyclization (example aminocyclopropane carboxylate synthase), or j8-elimation/replacement (example serine dehydratase) (2) loss of the a-carboxylate as carbon dioxide (example glutamate decarboxylase) (3) removal/replacement of a group by aldol cleavage (example threonine aldolase and (4) action via ketimine intermediates (example selenocysteine lyase). 

See specific aminotransferase Glutamate as a substrate or product, GLUTAMATE DECARBOXYLASE GLUTAMATE DEHYDROGENASE GLUTAMATE SYNTHASE GLUTAMINE SYNTHETASE y-GLUTAMYL TRANSPEPTIDASE LEUCINE AMINOTRANSEERASE LYSINE 6-AMINOTRANSEERASE... 

Glutamate decarboxylase found to be dependent on pyridoxal phsophate. 10... 

The other above-mentioned sensing system relies on measurement of carbon dioxide (rather than oxygen) produced in the biochemical reaction of L-glutamate catalysed by glutamate decarboxylase (GDC) ... 

Diaz-Munoz M, Tapia R. 1988. Glutamate decarboxylase inhibition and vitamin Be metabolism in brain of cirrhotic rats chronically treated with carbon tetrachloride. J Neurosci Res 20 276- 382. 

Dye, D.J., and Taberner, P.V. The effects of some newer anaesthetics on the in vitro activity of glutamate decarboxylase and GABA transminase in crude brain extracts and on the levels of amino acids in vivo. J. Neurochem. 24 997-1001, 1975. 

Kaufman, D. L., Erlander, M. G., Clare-Salzler, M., Atkinson, M. A., Maclaren, N. K., and Tobin, A. J. (1992). Autoimmunity to two forms of glutamate decarboxylase in insulin-dependent diabetes mellitus. J. Clin. Invest. 89, 283-292. 

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