Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.4.1.2 (glutamate dehydrogenase)
 4,380 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chain oxidation of glyceraldehyde-3-phosphate dehydrogenase.NADH by perhydroxyl radicals and propagated by molecular oxygen was studied by the xanthine-xanthine oxidase system, 60Co gamma-ray, and pulse radiolysis. The chain length, amount of NADH oxidized per HO2 generated, increases with increasing acidity of the medium and reaches a value of 73 at pH 5.0. The rate constant for the oxidation of the glyceraldehyde-3-phosphate dehydrogenase.NADH complex by HO2 was estimated to be 2 X 10(7) M-1 S-1 at ambient temperatures (23-24 degrees C). Rate studies as a function of pH indicate that O2- is unreactive toward the glyceraldehyde-3-phosphate dehydrogenase.NADH complex. Other dehydrogenases (malate dehydrogenase, glutamate dehydrogenase, and isocitric dehydrogenase) studied showed no catalytic activity in the oxidation of NADH by HO2/O2-.
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PMID:Glyceraldehyde-3-phosphate dehydrogenase-catalyzed chain oxidation of reduced nicotinamide adenine dinucleotide by perhydroxyl radicals. 718 97

The present review focuses on enzymes involved in the metabolism of amino acid neurotransmitters and the microphotometric determinations of their activities in various layers of the rat hippocampus. The enzymes are NAD-linked isocitrate dehydrogenase (NAD-ICDH), glutamate dehydrogenase (GDH), and GABA transaminase (GABAT), all of which are localized in mitochondria. GDH seems to be restricted to astrocytes, whereas NAD-ICDH and GABAT are localized in neurons as well as in astrocytes. NAD-ICDH is an important enzyme of the tricarboxylic acid cycle and may deliver alpha-ketoglutarate for the formation of glutamate and GABA, which serve as neurotransmitters in the hippocampus. GDH catalyses the interconversion of alpha-ketoglutarate and glutamate, whereas GABAT is the important GABA-degrading enzyme and requires alpha-ketoglutarate for its activity. While differing in their cellular distribution and activity levels, NAD-ICDH, GDH and GABAT are significantly correlated in their hippocampal distribution. Furthermore, developmental and pharmacohistochemical studies suggest that the distribution and activity of astrocytic GDH is correlated with amino-acidergic neurotransmission in the hippocampus. The data reported give further evidence for a metabolic relationship between neurons and astrocytes in the turnover and metabolism of glutamate and GABA.
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PMID:In situ measurements of enzyme activities in the brain. 810 May 59

To study the interactions between the citrate cycle and amino acid metabolism in zebrafish spinal motoneurons, we composed enzyme histochemical profiles from the activities of NAD-linked isocitrate dehydrogenase (NAD-ICDH), glutamate dehydrogenase (GDH), succinate dehydrogenase (SDH) and glucose 6-phosphate dehydrogenase (G6PDH). The enzyme assays were performed on serially-sectioned motoneuron somata. The motoneurons were identified by retrograde tracing from the trunk muscle and classified, on the basis of their location in the motor column, as those innervating the white, fast glycolytic fibers (WMNs) or those innervating the red and intermediate slow oxidative fibers (RIMNs). We found the following relationships between enzyme activities in WMNs: GDH correlates with G6PDH activity (r = 0.31; p = 0.02) and NAD-ICDH correlates with GDH activity (r = 0.37; p < 0.01); correlations between NAD-ICDH and SDH and between SDH and GDH are not significant. In RIMNs we found correlations between NAD-ICDH and SDH (r = 0.34; p = 0.03), between NAD-ICDH and GDH (r = 0.41; p < 0.01) and between GDH and SDH (r = 0.50; p < 0.01); the correlation between GDH and G6PDH is not significant. The differences in metabolic profiles between WMNs and RIMNs can be explained in the following way: in WMNs, alpha-ketoglutarate is drawn off from the citrate cycle and is used in amino acid metabolism whereas in RIMNs the removal of alpha-ketoglutarate from the cycle is balanced by formation of alpha-ketoglutarate. The data suggest that the functional role of the citrate cycle differs in the two motoneuron populations: in RIMNs energy generation predominates but in WMNs a role in biosyntheses seems most important.
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PMID:Metabolic profiles of white and red-intermediate spinal motoneurons in the zebrafish. 813 85

Severe iron deficiency results in complex systemic disorders e.g., including metabolism of energy and minerals. To investigate whether also moderate iron depletion may alter the activities of citric cycle enzymes and the cytochrome oxidase, the trace element status, and serum enzymes indicative of cell damage, this experiment was carried out with rats supplied with sub-optimal iron (9, 13 and 18 mg iron per kg diet) over a total of 5 weeks. The study included 3 pair-fed groups and an ad libitum group, fed with 50 mg iron/kg diet. All iron-restricted rats were classified as iron-deficient on the basis of reduced iron concentrations in body and iron-depending blood parameters. Body weight gain and catalase activity in kidney were lowered in rats receiving the lowest dietary iron level, exclusively. Rats fed 9 and 13 mg iron per kg diet had nearly 6- and 3-fold, respectively higher platelet counts in blood than their corresponding pair-fed controls. The activities of transaminases ASAT and ALAT, alkaline phosphatase, glutamate dehydrogenase and lactate dehydrogenase in serum which are indicative of cell damage were also markedly influenced by moderate dietary iron restriction, in which the enzyme levels in serum increased with intensifying iron depletion. Although, moderate iron restriction to young male rats was associated with marked alterations in iron status and serum enzymes, the activities of tricarboxylic acid cycle enzymes including malic dehydrogenase, fumarase, and isocitric dehydrogenase as well as cytochrome oxidase in liver remained largely unaffected. Only hepatic aconitase showed a somewhat reduction with iron depletion. Moreover, iron restriction was also accompanied with an accumulation of copper in liver which was significant for rats fed 9 and 13 mg iron per kg diet, whereas zinc status remained completely unaffected by moderate iron deficiency. It can be concluded, that a short-term moderate iron deficiency with ranging hemoglobin concentrations from 66 and 121 g/L, was accompanied with altered platelet counts, serum enzyme activities indicative of cell damage, and hepatic copper concentrations, but the activities of the tricarboxylic acid cycle enzymes and cytochrome oxidase in liver remained largely unaffected.
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PMID:Effect of different degrees of moderate iron deficiency on the activities of tricarboxylic acid cycle enzymes, and the cytochrome oxidase, and the iron, copper, and zinc concentrations in rat tissues. 980 Mar 17

Burchall, J. J. (University of Illinois, Urbana), R. A. Niederman, and M. J. Wolin. Amino group formation and glutamate synthesis in Streptococcus bovis. J. Bacteriol. 88:1038-1044. 1964.-Extracts of Streptococcus bovis grown on NH(4) (+) as a nitrogen source contain a nicotinamide adenine dinucleotide phosphate (NADP)-linked glutamic dehydrogenase and are devoid of alanine dehydrogenase, other amino acid dehydrohygenases, and aspartase. A potential source of reduced nicotinamide adenine dinucleotide phosphate for glutamate synthesis is a NADP and nicotinamide adenine dinucleotide (NAD)-linked glyceraldehyde-3-phosphate dehydrogenase present in the extracts. Experiments with C(14)-labeled glucose and NaHCO(3) indicate that the glutamate carbon skeleton is synthesized by a tricarboxylic acid pathway. The synthesis of the carbon skeleton of glutamate is repressed when glutamate or casein hydrolysate supplement the NH(4) (+)-containing growth medium. Repression of glutamic dehydrogenase and a NAD-linked isocitric dehydrogenase occurs only when complex nitrogen sources, but not when free amino acids, are added to the growth medium.
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PMID:AMINO GROUP FORMATION AND GLUTAMATE SYNTHESIS IN STREPTOCOCCUS BOVIS. 1421 16


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