Glutamic acid metabolism

Takagaki, G., S.Berl, D.D.Clarke, D.P.Purpura, and H.Waelsch. 1961. Glutamic acid metabolism in brain and liver during infusion with ammonia labeled with nitrogen-15. Nature 189 326. 

B3. Berl, S., Takajaki, G., Clarke, D. D., and Waelsch, H., Metabolic compartments in vivo. Ammonia and glutamic acid metabolism in brain and liver. J. Biol. Chem. 237, 2562-2570 (1962). 

Berl S, Lajhta A., and Waelsch H. (1961) Ammo acid and protein metabolism VI. Cerebral compartments of glutamic acid metabolism /... 

The amino group of the chromophore (1) is substituted amidically by small dibasic acids which all stem from the glutamic acid metabolism. In addition to the latter (ref. 20) succinic acid and its amide (refs. 18-21), malic acid (ref. 22) and a-keto glutaric acid (refs. 18-20) have been encountered (succinic acid seems to be an artefact stemming either from its amide or from a-keto glutaric acid). The mass of the acid present in the molecule can be deduced from a characteristic retro-Diels-Alder fragment of the quinoline nucleus in the FAB spectra of the free ligands (see m/z 985 in Fig. 1). 

Glutamic acid is formed m most organisms from ammonia and a ketoglutaric acid a Ketoglutaric acid is one of the intermediates m the tricarboxylic acid cycle (also called the Krebs cycle) and arises via metabolic breakdown of food sources carbohy drates fats and proteins... 

Certain amino acids and their derivatives, although not found in proteins, nonetheless are biochemically important. A few of the more notable examples are shown in Figure 4.5. y-Aminobutyric acid, or GABA, is produced by the decarboxylation of glutamic acid and is a potent neurotransmitter. Histamine, which is synthesized by decarboxylation of histidine, and serotonin, which is derived from tryptophan, similarly function as neurotransmitters and regulators. /3-Alanine is found in nature in the peptides carnosine and anserine and is a component of pantothenic acid (a vitamin), which is a part of coenzyme A. Epinephrine (also known as adrenaline), derived from tyrosine, is an important hormone. Penicillamine is a constituent of the penicillin antibiotics. Ornithine, betaine, homocysteine, and homoserine are important metabolic intermediates. Citrulline is the immediate precursor of arginine. 

The best results were obtained with L-aspartic add as the amino donor for P. denitrificam and phenylpyruvic add as the amino acceptor. With L-aspartic add, conversion of phenylpyruvic add exceeded 90%. This may be attributed to absence of feedback inhibition of the reaction due to metabolism of file reaction product, oxaloacetic add. When using glutamic acid the conversion of phenylpyruvic add did not exceed 60%. 

C14-0083. Although the ATP-ADP reaction is the principal energy shuttle in metabolic pathways, many other examples of coupled reactions exist. For example, the glutamic acid-glutamine reaction discussed in the text can couple with the acetyl phosphate reaction shown in Example 14-10. Write the balanced equation for the coupled reaction operating in the direction of overall spontaneity and calculate A G ° for the overall process. 

In earlier studies the in vitro transition metal-catalyzed oxidation of proteins and the interaction of proteins with free radicals have been studied. In 1983, Levine [1] showed that the oxidative inactivation of enzymes and the oxidative modification of proteins resulted in the formation of protein carbonyl derivatives. These derivatives easily react with dinitrophenyl-hydrazine (DNPH) to form protein hydrazones, which were used for the detection of protein carbonyl content. Using this method and spin-trapping with PBN, it has been demonstrated [2,3] that protein oxidation and inactivation of glutamine synthetase (a key enzyme in the regulation of amino acid metabolism and the brain L-glutamate and y-aminobutyric acid levels) were sharply enhanced during ischemia- and reperfusion-induced injury in gerbil brain. 

Kolko, M., DeCoster, M. A., Rodriguez de Turco, E. B. and Bazan, N. G. Synergy by secretory phospholipase A2 and glutamate on inducing cell death and sustained arachidonic acid metabolic changes in primary cortical neuronal cultures./. Biol. Chem. 271 32722-32728,1996. 

Vitamin Ba (pyridoxine, pyridoxal, pyridoxamine) like nicotinic acid is a pyridine derivative. Its phosphorylated form is the coenzyme in enzymes that decarboxylate amino acids, e.g., tyrosine, arginine, glycine, glutamic acid, and dihydroxyphenylalanine. Vitamin B participates as coenzyme in various transaminations. It also functions in the conversion of tryptophan to nicotinic acid and amide. It is generally concerned with protein metabolism, e.g., the vitamin B8 requirement is increased in rats during increased protein intake. Vitamin B6 is also involved in the formation of unsaturated fatty acids. 

Glue resin mixes, for the application of melamine resins, 15 791 Glufosinate, 13 299, 325, 326, 357 crop resistance to, 13 359-360 metabolism of, 13 360 Glutamic acid... 

The first example of a dynamic flux analysis was a study performed in the 1960s [269]. In the yeast Candida utilis, the authors determined metabolic fluxes via the amino acid synthesis network by applying a pulse with 15N-labeled ammonia and chasing the label with unlabeled ammonia. Differential equations were then used to calculate the isotope abundance of intermediates in these pathways, with unknown rate values fitted to experimental data. In this way, the authors could show that only glutamic acid and glutamine-amide receive their nitrogen atoms directly from ammonia, to then pass it on to the other amino acids. 

Sterol biosynthesis Bile acid biosynthesis C2rSteroid hormone metabolism Androgen and estrogen metabolism Nucleotide Metabolism Purine metabolism Pyrimidine metabolism Nucleotide sugar metabolism Amino sugar metabolism Amino Acid Metabolism Glutamate metabolism Alanine and aspartate metabolism Glycine, serine, and threonine metabolism... 

Metabolism of Other Amino Acids /3-Alanine metabolism Taurine and hypotaurine metabolism Aminophosphonate metabolism Selenoamino acid metabolism Cyanoamino acid metabolism D-Glutamine and D-glutamate metabolism... 

Summarizing, muscle protein provides a number of compounds which can generate fuel for other tissues, a fact which explains the severe wasting seen in people who are literally starving, as muscle protein is sacrificed to maintain function of the central nervous system in particular. We have also seen how glutamate plays a central role in amino acid metabolism in muscle (Figure 7.20). 

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