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 (0.00 seconds)

Specific antispermidine antibodies were produced following immunization of New Zealand white rabbits with a spermidine-thyroglobulin conjugate of high (greater than 200:1) hapten-carrier molar ratio. The harvested antispermidine rabbit antiserum was characterized and a radioimmunoassay procedure developed. The specificity of this antibody was tested against cadaverine, putrescine, spermine, monoacetylputrescine, N-8-acetylspermidine and other compounds of similar molecular structure. Negligible cross-reactivity was observed with putrescine (2.1%), cadaverine (0.6%), spermine (0.3%), diaminopropane (less than 0.1%), and no cross-reaction was found with monoacetylputrescine, N-8-acetylspermidine, histamine, L-lysine and L-ornithine. The spermidine values on serum of five healthy volunteers were determined by RIA and compared with values by gas chromatographymass spectrometry. Statistical evaluation of the results were highly agreeable. Antibody titer, intra-assay precision and analytical accuracy were tested. The assay requires only 20 microliter of serum and has picomole sensitivity. The sensitivity, specificity and small sample requirement make this procedure an effective tool for spermidine analysis.
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PMID:Radioimmunoassay of spermidine in human serum. 56 28

Insulin hexamethyl ester was digested by trypsin. The resulting desoctapeptide-(B23 - 30)-insulin pentamethyl ester was purified. This compound was digested by carboxypeptidase B to remove the arginine residue B22 at the end of the B chain. Then the N-terminal amino groups of the remaining desnonapeptide-(B22 - 30)-insulin pentamethyl ester were protected with the Boc residue. The free carboxyl group of the glutamic acid residue B21 of this product was coupled to the following synthetic tetrapeptide esters: Arg-Gly-Phe-Phe-OMe, Lys(Boc)-Gly-Phe-Phe-OMe, Orn(Boc)-Gly-Phe-Phe-OMe, Cit-Gly-Phe-Phe-OMe, Ala-Gly-Phe-Phe-OMe and Gly-Gly-Phe-Phe-OMe. The syntheses of these peptide esters are described. After removal of all protecting groups, despentapeptide-insulin (B22-Arg) and analogues of this product with variation in position B22 could be obtained. They were purified by column chromatography. The biological activities of these components were determined by the mouse fall test. In the case of despentapeptide insulin (C-terminus Arg-Gly-Phe-Phe), the activity rose to the expected value of 34%. The insulin variants with amino acid residues other than arginine in position B22 had much lower activities: with lysine 13%, with ornithine 12%, with citrulline 9%, with alanine 8% and with glycine 6%. Desnonapeptide-insulin by itself posses an activity of 3%. These results demonstrate once more the essential nature of arginine residue B22 for insulin activity.
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PMID:Structure and activity of insulin, XV[1-5]. Further evidence for the importance of arginine residue B22 in the activity of insulin. Semisyntheses of despentapeptide-(B23 - 30)-insulins varied in B22 using desnonapeptide-(B22 - 30)-insulin and tetrapeptides. 59 Sep 40

Application of chlortetracycline in rats resulted in the occurence of certain peptides in the blood-serum, which could not be detected in the serum of an untreated control group. These results were obtained by means of high voltage electrophoresis and paper electrophoresis of the serum of rats which was analyzed 1,3, and 13 hours respectively after a single dose of 50 mg chlortetracycline per 100 g body weight in comparison to an untreated control group. The new peptides could be found in the slight alkaline range 1 and 3 hours after application of chlortetracycline and in the strong acidic area of the electrochromatogram 13 hours thereafter. A more detailed investigation of the new peptides could demonstrate that the number of the following amino acids was reduced in the peptide chains after chlortetracycline: leucine, valine, serine, arginine, and lysine. On the other hand, amino acids, such as citrulline, sarcosine, alpha-aminobutyric acid, and ornithine, could be found which are normally not present in proteins.
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PMID:[Effect of chlortetracycline on the peptide spectrum of rat serum]. 59 Nov 62

Two active lysine transport systems were detected in Saccharomycopsis lipolytica. No excretion of lysine out of the cells could be obtained, even by chasing with L-lysine or by poisoning with sodium azide. The kinetic properties of one of the permeases, the high-affinity lysine permease, were studied in detail. Its Km was 1.91 +/- 0.23 X 10(-5) M. It proved highly specific, the only potent competitive inhibitors being (i) arginine and its analogs L-canavanine and L-ornithine, and (ii) the lysine analogs L-5 aminoethylcysteine and L-4,5-transdehydrolysine. It is suggested that the high-affinity lysine permease is common to L-lysine, L-ornithine, and L-arginine. The other amino acids tested behaved as noncompetitive inhibitors. The variation of uptake during a growth cycle was studied on ammonia-rich, ammonia-poor, and ammonia-free media. In each case, the uptake exhibited a peak in the early exponential growth phase. No new permease activity was detected during the lag phase or the stationary phase. Ammonia ions competitively inhibited the uptake and also decreased the Vmax value.
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PMID:Physiology of lysine permeases in Saccharomycopsis lipolytica. 62 30

Twenty amino acids were examined for their effects on urinary orotic acid excretion. Except for arginine and ornithine, all of the remaining amino acids tested induced a mild orotic aciduria in rats 2 hours post feeding. Two ammonium salts, and urease also acted, as inducers of orotic aciduria. The ammoneogenic properties of the amino acids tested could not solely explain the induced excretion of orotic acid. Only serine, glutamine, NH4Cl, (NH4)2CO3, and urease increased orotic acid excretion in the 24 hour fasted rat. Administration of 0.5 mmoles of arginine or ornithine ameliorated the mild orotic aciduria induced by either glycine or lysine. Arginine was shown to be more efficacious in preventing glycine induced orotic aciduria than was ornithine. Amino acid induced orotic aciduria is dependent upon the physiological state of the animal, varying with the state of digestion and the supply of arginine.
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PMID:Amino acid induced orotic aciduria. 63 45

Plasma amino acid concentrations were measured in peripheral venous blood of 40 newborn infants breast-fed ad libitum. When these data are compared with amino acid concentrations of umbilical cord artery plasma, only lysine and threonine show a striking decrease after birth: the concentrations of hydroxyproline, asparagine, glutamine, proline, cystine, leucine, tyrosine, and ornithine significantly increase during the first days of life. The high-protein concentration of colostrum and transitional milk may explain this observation.
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PMID:Plasma amino acid concentrations in newborn infants breast-fed ad libitum. 63 24

28 plasma amino acids of 40 female patients with rheumatoid arthritis (RA), 24 male patients with ankylosing spondylitis (ASp) and 19 controls (14 females and 5 males) were investigated. In RA-patients 19 amino acids showed statistically significant differences to healthy people of which 18 were decreased. In ASp-patients 14 amino acid concentrations were statistically altered whereby 10 showed enhanced values. In female RA-patients and controls a linear dependency between distinct amino acids (threonine, glutamic acid, proline, alanine, citrulline, tyrosine, phenylalanine, ornithine, lysine and 3-methylhistidine) - and advanced age could be demonstrated.
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PMID:Plasma amino acid level in rheumatoid arthritis and ankylosing spondylitis and its variation during age. 63 65

Inulin and amino acid clearance studies were made in 6 boys with oculocerebrorenal syndrome (Lowe) aged 11 months to 5 years. Glomerular filtration rate ranged between 50 and 112 ml/min/1.73 m2. Clearance values of all amino acids were increased. Tubular reabsorption of cystine, ornithine, lysine and arginine was relatively more reduced than that of the other amino acids. In Lowe's syndrome the transport system of the basic amino acids and cystine appears to be more impaired than that of other amino acids.
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PMID:Renal transport of amino acids in children with oculocerebrorenal syndrome. 66 70

Aspergillus candidus produced an exocellular protease at a high rate in the absence of nitrogen sources. Nineteen amino acids were added separately as sole nitrogen sources to the medium to study their effect on biosynthesis of exoproteases. All the amino acids were found to repress the biosynthesis, arginine, histidine, lysine and ornithine being most effective among them. Repression of the biosynthesis of exoproteases in the presence of amino acids added as sole nitrogen sources is presumed to be accomplished by ammonium ions which are formed in the course of utilization of amino acids. The level of repression is proportional to the concentration of an amino acid in the medium. Amino acids have no effect on the activity of exocellular proteases synthesized by Aspergillus candidus.
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PMID:[Effect of amino acids as sole nitrogen sources on exoprotease biosynthesis in Aspergillus candidus]. 67 80

(1) The arterio-venous difference technique, previously used to measure mammary substrate uptake with cows and goats, was used to measure amino acid uptake by the mammary gland of the lactating Merino ewe. Possession of a single large superficial epigastric vein by the Merino ewe makes the Merino breed the most suitable for this type of study. (2) A method was developed enabling hourly measurement of milk yield without causing undue stress. Milk yield was essentially constant over a 7-8 h period. (3) Mammary extraction of most non-essential amino acids was low relative to output in milk protein and showed a greater variability with time than that found for the essential amino acids. There was a significant mammary extraction of ornithine and citrulline, neither amino acid being found in ovine milk protein. (4) Of the essential amino acids valine, isoleucine, leucine and arginine were taken up in excess of their requirement for milk protein synthesis. (5) On the basis of the extent of mammary extraction, methionine, lysine and leucine were first-, second- and third-limiting to the rate of milk protein synthesis. (6) Despite fluctuations in arterial amino acid concentrations the arterio-venous differences of the essential amino acids were relatively constant over a 7-8 h period. (7) The pattern of mammary amino acid uptake in the ewe is contrasted with that found in similar studies carried out with the lactating cow and goat.
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PMID:Amino acid uptake by the mammary gland of the lactating ewe. 67 19


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