Urine glutamic acid

The amounts of single amino acids excreted in urine in the conjugated form, as determined independently by Stein and Muting, are given in Tables 1 and 2. According to Stein, glycine, glutamic acid, aspartic acid, histidine, and proline are quantitatively the most important amino acids liberated in the course of urine hydrolysis. Serine, lysine, tyrosine, cysteine and cystine, threonine, alanine, valine, phenylalanine, and leucine are... 

As early as 1905 Abderhalden (Al) isolated from the hydrolyzate of the nondiffusible fraction of human urine four amino acids, i.e., leucine, alanine, glycine, and glutamic acid, and detected two others phenylalanine and aspartic acid. Some amino acids derived from this fraction have been quantitatively determined by Albanese et al. (A3) who found in the amount of the nondiffusible fraction corresponding to one liter of urine as much as 32.8 mg tryptophan, 18.0 mg phenylalanine, 16.2 mg methionine, 15.2 mg cystine, 13.1 mg arginine, 6.7 mg histidine, and 3.9 mg tyrosine. 

Stein et al. found in the course of experiments dealing with free and conjugated urinary amino acids in Wilson s disease (S9) that besides a marked aminoaciduria, almost a twofold increase in the excretion of all bound amino acids could be observed. As compared with normal urine (S8), unusual amounts of conjugated leucine, isoleucine, and valine are excreted in cases of Wilson s disease. Also the increase of glutamic acid, aspartic acid, and phenylalanine after urine hydrolysis is much more distinct in this disease than in normal conditions. Other bound amino acids are at or below normal levels. 

In the course of studies on aminoaciduria in Fanconi s syndrome, Dent (Dl) isolated from the urine of the subject investigated a simple peptide identified as serylglycylglycine. Carsten (Cl) found in normal urine several peptides containing in every case one of the dicarboxylic amino acids. He discovered also two tetrapeptides, one of them consisting of equimolar amounts of aspartic acid and glycine, and the second composed of glycine, alanine, and glutamic acid in the ratio 2 1 1. The first of these tetrapeptides was also found in the urine of a patient with rheumatoid arthritis. 

Plaquet et al. (PI) found in the urine of rachitic children peptides consisting of proline, hydroxyproline, and glycine, which they believed to be the products of collagen degradation. Two similar peptides containing considerable amounts of proline and hydroxyproline were isolated from the urine of a patient with rheumatoid arthritis by Mechanic et al. (Ml). One of these peptides consisted of three proline, two hydroxyproline, and nine glutamic acid residues, the second one consisted of four proline, four hydroxyproline, and one glutamic acid residues. The N-terminal amino acid in the first peptide was demonstrated to be hydroxyproline. 

By means of a procedure described above, Hanson and Fittkau (HI) isolated seventeen different peptides from normal urine. One of them, not belonging to the main peptide fraction, consisted of glutamic acid, and phenylalanine with alanine as the third not definitely established component. The remaining peptides contained five to ten different amino acid residues and some unidentified ninhydrin-positive constituents. Four amino acids, i.e., glutamic acid, aspartic acid, glycine, and alanine, were found in the majority of the peptides analyzed. Twelve peptides contained lysine and eight valine. Less frequently encountered were serine, threonine, tyrosine, leucine, phenylalanine, proline, hydroxyproline, and a-aminobutyric acid (found only in two cases). The amino acid composi-... 

P2. Pollack, R. L., and Eades, C. H., Glucuronic acid conjugates of aspartic and glutamic acids in urine. Science 119, 510-511 (1954). 

B36. Broquist, H. P., and Luhby, A. L., Detection and isolation of formimino-glutamic acid from urine in folic acid deficiency in humans. Proc. Soc. Exptl. Biol. Med. 100, 349-354 (1959). 

The available data suggest that the amount of D-glutamic acid cyclotransferase in mammalian kidney and liver is sufficient to explain the appearance of D-pyrrolidone carboxylate in the urine of animals that... 

The chromatograms always indicate the excretion of considerable amounts of glutamine (and glutamic acid), but it is not possible to arrive at accurate values for glutamine (see text). The values for this amide are therefore to be considered as very approximate, indicating merely that it is found in urine in considerable amounts. 

The normal pattern of the urine is characterized by the presence of five amino acids which give prominent spots. These are glycine, serine, alanine, glutamine, and histidine. Moderate amounts to traces of lysine, threonine, glutamic acid, taurine, methylhistidine, and j8-aminoiso-butyric acid occur in some normal samples (Fig. 4). Soupart (S42) and Peters et al. (P17) have published data on the urinary excretion of the free amino acids by normal human subjects which provide a useful compilation of the current knowledge in this field (Table 4). 

This amide of glutamic acid has properties similar to those of asparagine. The y-amido nitrogen, derived from ammonia, can be used in the synthesis of purine and pyrimidine nucleotides (Chapter 27), converted to urea in the liver (Chapter 17), or released as NH3 in the kidney tubular epithelial cells. The last reaction, catalyzed by the enzyme glutaminase, functions in acid-base regulation by neutralizing H+ ions in the urine (Chapter 39). 

After orally ingested, L-theanine is absorbed into the blood circulation through the small intestinal tract s brush-border membrane and then distributed to tissues." " It is easily transported into the brain through the blood-brain barrier s leucine-preferring amino acid transporter system L-Theanine does not appear to accumulate. The metabolic fate of theanine after its oral administration was verified to be enzymatically hydrolyzed to glutamic acid and ethylamine in the blood, kidney, liver, and brain then most of the ethylamine generated was immediately excreted into urine, with only a part circulated in plasma. It is completely absent 24 h after administration. 

Natural L-theanine is synthesized from glutamic acid and ethylamine in the root of the tea plant and transferred to young leaves. Theanine is absorbed by a common Na+-coupled cotransporter in the intestinal brush-border membrane and incorporated into the brain via the leucine-preferring transport system of the blood-brain barrier. L-Theanine does not appear to accumulate it is metabolized in the blood, liver, and brain, and then completely eliminated in the urine within 24 h. 

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