Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: CAS:1069-31-4 (ornithine)
 6,755 document(s) hit in 31,850,051 MEDLINE articles (0.04 seconds)

Extracts of Fusarium roseum (ATCC 12822) contain an enzyme which hydrolyzes the ornithine ester bonds of fusarinine C, a cyclic trihydroxamic acid produced by this organism. The methyl ester of Ndelta-dinitrophenyl-L-ornithine is also a substrate for the enzyme, and an assay was devised using this substrate. The enzyme exhibits a sharp maximum of activity at pH 7.5 and is extremely temperature sensitive. It is strongly inhibited by HgCl2 and p-chloromercuribenzoate, and it is competitively inhibited by Ndelta-dinitrophenyl-D-ornithine methyl ester (Ki = 0.3mM). Methyl esters of glycine, L-alanine, dinitrophenyl-L-alanine, dinitrophenyl-beta-alanine, and Ndelta-dinitrophenyl-Nalpha-acetyl-L-ornithine are not substrates, although Nepsilon-dinitrophenyl-L-lysine methyl ester is as effective as the ornithine derivative. Nonspecific lipases do not hydrolyze ornithine esters, nor does trypsin. The three ester bonds of fusarinine C are progressively hydrolyzed by the enzyme to eventually yield the monomer, fusarinine. The ferric chelate of fusarinine C is not hydrolyzed. An enzyme from Penicillium sp. was isolated with identical properties toward Nbeta-dinitro-phenyl-L-ornithine methyl ester as substrate. It also hydrolyzes N,N',N"-triacetylfusarinine C, a cyclic trihydroxamate containing Nalpha-acetylornithine ester bonds, which is produced by this organism. This substrate is hydrolyzed to Nalpha-acetylfusarine. In contrast to the Fusarium enzyme, this enzyme is fully active toward the ferric trihydroxamate chelate. However, replacement of iron by aluminum leads to a completely inactive substrate. Production of the enzyme is severely suppressed by iron in the growth medium. It is proposed that these specific ornithylesterases provide a mechanism of cellular iron release by hydrolysis of the ferric ionophores, and that an iron-exchange step occurs prior to, and is a prerequisite for, hydrolysis of the ester bonds.
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PMID:Fungal ornithine esterases: relationship to iron transport. 94 72

Cycloleucinead ministration (a synthetic amino acid) to rats produces a selective hyperaminoaciduria bearing on dibasic amino acids (lysine, arginine, ornithine) and cystine. Interference of cycloleucine with tubular reabsorption of these amino acids was studied "in vitro", using rat kidney cortex slices. When dibasic amino acids and cystine are at physiological concentrations, the data indicate that cycloleucine decreases their intracellular accumulation. However, effect of cycloleucine "in vitro" is not specific whatsoever its concentration; similar results are obtained with neutral amino acids such as alpha-alanine and valine. Inhibitory effects are not modified by the presence of several amino acids in the incubation medium. The results are interpreted as evidence for a dissociation between "in vitro" cellular accumu-lation and "in vivo" transepithelial transport.
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PMID:[Effect of cycloleucine on renal uptake of dibasic amino acids and cystine]. 96 87

The reactions of lysine, ornithine and arginine decomposition are often difficult to read in Falkow's medium because either the decolorization of the indicator or the lack of sharp colour differences between positive and negative reactions. In such cases Nessler's reagent may be a useful aid. A volume of about 0.2 ml is added to the cultures after 4 days incubation through the mineral oil layer by means of a pipette. A positive reaction is indicated by an immediate white precipitation in case of lysine and ornithine decarboxylation, and a white or brownish precipitate which indicates arginine decomposition. A delayed opacity should be regarded as a negative reaction. Only unequivocal reactions should be considered. The specificity of the reactions was tested with pure substances of compounds which are formed by the decomposition of lysine, ornithine and arginine. Further studies of bacterial cultures in Falkow's medium and in a synthetic, amino acid containing medium without peptone gave identical results and showed that peptone derivates do not cause a false positive reaction with Nessler's reagent (Table 1). Comparative studies on 605 strains of Enterobacteriaceae and Vibrio in Falkow's medium with and without added Nessler's reagent gave corresponding results except some strains of Escherichia coli and Citrobacter freundii with different arginine reactions (Table 2). Strains of these species mostly decolorized the indicator thereby hindering the recognition of either a true positive or a true negative reaction. In these cases, however, the results obtained after addition of Nessler's reagent corresponded closely to the percentage of positive reactions cited in the literature.
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PMID:[Use of Nessler's reagent for recognition of lysine, ornithine, and arginine decomposition by gramnegative fermentative bacteria (author's transl)]. 99 31

A 3-year-old boy with hyperdibasicaminoaciduria and hyperammonemia showed characteristics of familial protein intolerance (FPI). Oral loading tests of lysine and arginine disclosed a remarkably reduced capability for intestinal absorption of these amino acids. Because urinary excretion and renal clearance of dibasic amino acids were only moderately elevated in the patient, the conspicuously decreased serum concentration of lysine, arginine, and ornithine was attributed to the defect in internal absorption. A possible explanation for elevated blood ammonia levels in FPI is that it is due to a deficiency of arginine and ornithine in the urea cycle that in turn results from a severe impairment in absorption of the amino acids by the gut mucosa.
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PMID:Hyperdibasicaminoaciduria and hyperammonemia in familial protein intolerance. 99 77

1. Two women with severe hypokalaemic alkalosis were investigated by means of muscle biopsy before and at the end of 2 and 3 weeks respectively of intense therapy with potassium chloride. 2. The muscle biopsy material was analysed for water, electrolytes, adenine nucleotides, phosphocreatine, free creatine, pyruvate, lactate, glycogen and free amino acids. The extra- and intra-cellular distribution of water, electrolytes and amino acids was calculated by the chloride method. 3. Both patients showed a marked loss of intracellular potassium and an increase in intracellular sodium concentration. The muscle magnesium content was also slightly decreased. After repletion with potassium chloride, muscle sodium and potassium became normal. 4. The contents of creatine phosphate, ATP, ADP, AMP, lactate and pyruvate were within normal limits, but the phosphocreatine/total creatine ratio was reduced. After repletion, a small change in the apparent creatine-phosphokinase equilibrium had occurred, suggesting a minor increase in intracellular pH. 5. The concentrations of the basic amino acids, lysine, arginine and ornithine were increased far above normal. The intracellular accumulation of arginine was much higher than the increase in lysine concentration and histidine concentration was normal. This differs from findings in potassium-depleted rats, where the intracellular lysine concentration is much higher than arginine concentration and histidine is high as well. After potassium repletion the intracellular concentration of ornithine, lysine and arginine became normal in one case and decreased considerable in the other. An increased intracellular concentration of glutamate and glutamine was also observed after potassium repletion.
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PMID:Influence of severe potassium depletion and subsequent repletion with potassium on muscle electrolytes, metabolites and amino acids in man. 107 Apr 23

A chemically defined medium for Veillonella parvula and V. alcalescens is described. Some nutritional aspects of the two strains used were examined: the optimum concentration of reducing agents, the requirements for amino acids, diamines, vitamins and other growth factors, and the conditions needed for well balanced nutrition. No specific requirements for single amino acids were observed. A combination of L-cysteine, DL-aspartic acid, L-glutamic acid, L-serine and L-tyrosine, promoted growth. In V. alcalescens, serine could substitute both arginine and tryptophan (or histidine). No growth was obtained with ammonium salts as the sole N source. Decarboxylation of L-ornithine, L-lysine and L-arginine was not demonstrated in the Veillonella parvula strain, which required putrescine or cadaverine for growth. Spermine, spermidine, L-lysine, L-ornithine and L-arginine, could not substitute putrescine in Veillonella parvula. Veillonella alcalescens, which does not require putrescine in the medium, was able to decarboxylate L-ornithine while forming putrescine.
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PMID:Chemically defined media for growing anaerobic bacteria of the genus Veillonella. 108 58

Mutants selected on the basis of their resistance to S-(beta-aminoethyl) cysteine and overproduction of lysine were found to be defective in the lysine transport system. The overproduction of lysine was not due to mutation affecting either of the two regulatory enzymes aspartokinase and dihydrodipicolinic acid synthetase. Uptake of labeled lysine by the lysine-specific transport system was reduced to a negligible level, while uptake by the lysine, ornithine, arginine system was also affected. A hypothesis regarding the nature of these mutations and their effects on the regulation of lysine biosynthesis is discussed.
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PMID:Overproduction of lysine by mutant strains of Escherichia coli with defective lysine transport systems. 109 14

Relationship of citrate synthase (EC 4.1.3.7) to the biosynthesis of glutamic acid was investigated by characterizing a new glutamic acid auxotroph FL100-D1 (glu 3) of Saccharomyces cerevisiae. Nutritional requirement of the mutant was satisfied by L-glutamic acid, L-glutamic acid peptide as well as several analogs of glutamic acid, but not by proline, ornithine, arginine, lysine or aspartic acid. The mutant was unable to utilize nonfermentable carbon sources, glycerol, acetate or lactate. Mutant glu3 unlike aconitaseless glutamic acid auxotroph glu 1, failed to accumulate 14C-citric acid in vivo from 1-14C-sodium acetate or U-14C-glutamic acid. Both spectrophotometric and radioactive assay procedures demonstrated a lack of significant citrate synthase activity in the dialysed extract of the mutant compared to the wild type strain. Mutant glu 3 complemented with glu 1 and glu 2 individually in vivo and exhibited a significant aconitase (EC 4.2.1.3) activity in vitro.
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PMID:Citrate synthaseless glutamic acid auxotroph of Saccharomyces cerevisiae. 110 43

Free amino acids in the tonsils of 20 individuals were measured column chromatographically. Those always found in readily detectable amounts included O-phosphoserine, taurine, O-phosphoethanolamine, aspartic acid, hydroxyproline, threonine, serine, glutamic acid, proline, glycine, alanine, alpha-amino-n-butyric acid, valine, cystine, methionine, isoleucine, leucine, tyrosine, phenylalanine, ornithine, gamma-amino-butyric acid, lysine, histidine, and arginine. Results were compared for three clinical pathological groups and for four age groups. Some abnormal values may result from the pathological conditions.
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PMID:Free amino acids in human tonsillar tissue. 111 54

Two water-soluble basic antibiotics named galantins I and II were isolated from a strain resembling Bacillus pulvifaciens. Both antibiotics are peptides containing glycine, alanine, ornithine, lysine and some unknown ninhydrin-positive components. An approximate empirical formula C50 plus and minus H98plus and minus 2O17N16 is indicated for galantin I. These are active against some gram-positive, acid-fast and gram-negative bacteria.
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PMID:Isolation of galantins I and II, water-soluble basic peptides. Studies on antibiotics from the genus Bacillus. III. 111 63


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