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)

The features of the structure of lysine, linked to Sepharose by the alpha-amino group, which are important for affinity chromatography of rabbit plasminogem were studied. Nine lysine and lysine-like conjugates, including epsilon-aminohexanoic acid DL-norleucine, DL-alpha-aminoadipic acid, DL-alpha-epsilon-diaminopimelic acid, cadaverine L-ornithine, L-arginine and D-lysine, were prepared; Using labelled rabbit plasminogen added to plasma, the ability of each conjugate to absorb plasminogen and separate the allomeric forms, type I and type II, during epsilon-aminohexanoic acid gradient elution was compared to Sepharose-L-lysine. Plasminogen had no affinity for Sepharose-epsilon-aminohexanoic acid, and was only weakly attracted by Sepharose-norleucine, Sepharose-cadaverine and others. Sepharose-ornithine held a greater attraction to the protein but the strongest binding was obtained with Sepharose-arginine. The affinity of plasminogen type I was always less than type II for the Sepharose-lysine analogues and the recovery of type II greater than type I from Sepharose-ornithine and Sepharose-arginine. Plasminogen affinity was in the order of Sepharose-arginine greater than Sepharose-lysine greater than Sepharose-ornithine. However, because of the present difficulty in recovering plasminogen from Sepharose-arginine the use of Sepharose-lysine in the affinity chromatography of rabbit plasminogen remains unchallenged. It is concluded that binding of rabbit plasminogen to conjugates of lysine and its analogues is determined by the presence of both a free carboxyl and a free amino group and that the distance between these groups is critical.
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PMID:The relevance of the structure of lysine bound to Sepharose for the affinity of rabbit plasminogen;. 112 1

Uptake of diamino acids by isolated granulocytes and by liver slices was studied in patients with LPI and in control subjects. 14-C-Labeled lysine, arginine, and ornithine were used in the granulocyte assay and a nonmetabolizable diamino acid analog, l-homoarginine, in the liver assay. Kinetic studies on diamino acid uptake by the granulocytes were consistent with the existence of one transport system common to the three diamino acids. The maximal velocity of uptake was approximately equal for the three amino acids and similar in patients and control subjects. In the liver slices, at least two transport systems became apparent as substrate concentration was varied from 4.0-0.025 mM. A low concentration system with high affinity and very small capacity for transport was similar in patients and control subjects. A high concentration system was also present in both groups, but in the patients had only 1/7 of the maximal capacity observed in the control subjects. This defect grossly incapacitated the diamino acid uptake of the liver. In LPI, the observed defect, in conjunction with the deficient absorption in the kidneys and intestine, explains the lack of ornithine at the site of urea synthesis, which is evident from the impaired and ornithine-correctable urea production.
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PMID:Diamino acid transport into granulocytes and liver slices of patients with lysinuric protein intolerance. 113 47

Lysine vasopressin did not increase plasma FFAs level in man and in rat Pitressin and lysine vasopressin did not influence adenyl cyclase activity in rat epididymal fat pad, while ornithine vasopressin induced a statistically significant adenyl cyclase increment. These findings suggest that the adipokinetic acticity of ADH which has been correlated only with the amino acid arginine is also correlated with ornithine.
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PMID:Antidiuretic hormone and lipolysis. 114 94

The amino acid composition of lung, serum and liver in silicotic rats was studied in order to assess the availability of precursors in lung for fibrogenesis. It was observed that the pool of ornithine, arginine, alanine, leucine, valine, glutamic acid, lysine, proline and glycine underwent marked alterations. Free arginine, proline and leucine were only detectable in silicotic lung, while free glycine, glutamic acid and glutamine pools decreased significantly in liver. Changes in amino acid metabolism as a result of silicosis are discussed.
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PMID:Changes in free and bound amino acids in experimental silicosis. 114 26

Lysinuric protein intolerance (LPI), an autosomal recessive defect of diamino acid transport, is characterized chemically by renal hyperdiaminoaciduria, especially lysinuria, and by impaired formation of urea with hyperammonemia after protein ingestion. Our 20 patients thrived during breast-feeding, but ingestion of cow's milk caused diarrhea and vomiting. When able to select their diet, they rejected all protein-rich foods. They were short staturated and had weak atrophic muscles, osteoporosis, hepatomegaly and often splenomegaly. Four patients were mentally retarded. Fifteen patients had leukocyte counts below 4,000/mm3, and 17 patients had platelet counts below 150,000/mm3. Serum lactate dehydrogenase activity was constantly increased, and transaminase and aldolase activities were often increased. In the infants' livers, changes were only revealed by electron microscopy: increased and vesicular smooth endoplasmic reticulum, and abundance of glycogen particles in the hepatocytes. In the older patients, light microscopy demonstrated clearly limited areas where hepatocytes had large pale cytoplasm and small pyknotic nuclei. The diamino acids lysine, arginine and ornithine had plasma concentrations only one-third to one-half the normal mean; the renal clearances were clearly increased. Oral diamino acid loading tests suggested impaired intestinal absorption. Urea is built in the liver through transformation of ornithine to arginine, and cleavage of arginine to ornithine and urea. The addition of ornithine to an intravenous I-alanine loading prevented the hyperammonemia and normalized the urea production. Therefore, the diet has been supplemented with arginine, and more protein has been added. This therapy has lead to a remarkable catch-up growth in some patients. The pathophysiology of LPI is explained. Because of defective intestinal absorption and incrased renal loss, the diamino acids have a low plasma concentration. Their transport from plasma to hepatocytes is also impaired, and the liver becomes deficient in ornithine. This retards the urea cycle, and leads to postprandial hyperammonemia and protein aversion. The presence of the transport defect in the hepatocytes distinguishes LPI from other hyperdibasicaminoacidurias.
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PMID:Lysinuric protein intolerance. 115 80

The biologically active partial sequence Arg-Gly-Phe-Phe (position B 22-25 of the insulin B chain) in the form of the synthetic tetrapeptidamide, was compared in several bioassays with the following analogous synthetic peptides: homoarginyl-, ornithyl-, lysyl-, citrullyl-, alanyl- and NG-nitroarginyl-Gly-Phe-Phe-NH2. The syntheses of the lysyl- and alanyl-tetrapeptidamides are described. After intraperitoneal injection of the peptides in doses of 3-100 mumol per 100 g rat, together with [U-14C]glucose, the natural sequence Arg-Gly-Phe-Phe showed the highest insulin like activity (incorporation of labeled carbon into the diaphragm). The activity of the homoarginyl peptide was a little weaker. The ornithyl- and the lysyl-peptide, however, showed a remarkably diminished activity. The activity of the citrullyl-peptide was even lower and the alanyl-peptide was inactive. In vitro assays with rat diaphragm showed the same range of effects for the elevation of glucose uptake and glycogen content of the diaphragm. The activity decreased in the following order: Arg- greater than Har- greater than Orn- greater than Cit-Gly-Phe-Phe-NH2. Alanyl- and Nitroarginyl-Gly-Phe-Phe-NH2 were without effect. In isolated fat cells the glucose oxidation was enhanced significantly only by the arginyl-peptide. The results show that among the structures examined the guanidino group carried by the C5 chain of arginine is the most effective. The results are in accordance with our preceding work [1] using semisynthetic insulins obtained from natural A-chain and synthetic B-chain variants. In these products the replacement of Arg B 22 by ornithine or lysine also led to drastically diminished activity and after replacement of Arg B 22 by alanine the activity also disappeared.
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PMID:Structure and activity of insulin, XIII. Specificity of the arginine-guanidino group in biologically active tetrapeptides of the insulin sequence B 22-25 (Arg-Gly-Phe-Phe). 115 33

The peptide antibiotic longicatenamycin produced by a Streptomyces strain S-520 is a complex mixture of several congeners. The determination of the total structure of longicatenamycin was performed on the mixture using the procedure of N-bromosuccinimide oxidation followed by EDMAN degradation. The structure of the most abundant congener of longicatenamycin can be represented as cyclo (glycyl-L-2-amino-6-methylheptanoyl-D-valyl-D-ornithyl-threo-beta-hydroxy-L-glutamyl-5-chloro-D-tryptophyl) (Fig. 1: 1=4, m=0, n=3). There are three amino acid positions in which variations are found. The antibiotic complex contains compounds in which L-2-amino-6-methyl-heptanoic acid is replaced with either L-2-amino-5-methylhexanoic acid of L-2-amino-7-methyloctanoic acid; further D-valine with D-isoleucine as well as D-ornithine with D-lysine.
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PMID:The total structure of the antibiotic longicatenamycin. 115 81

Splanchnic metabolism was studied in the fed state during prolonged intravenous administration (30 g/h) of either fructose or glucose to hypertriglyceridemic men who had been maintained on a high-carbohydrate diet for 2 wk. Splanchnic exchange of amino acids and carbohydrates was quantified by measurement of splanchnic flow and of blood or plasma arteriohepatic venous concentration gradients. Results obtained in subjects receiving fructose were compared with those obtained in (a) similar subjects receiving glucose and (b) postabsorptive controls maintained on isocaloric, balanced diets. Mean arterial plasma levels of alanine, glycine, serine, threonine, methionine, proline, valine, leucine, histidine, lysine, and ornithine were significantly higher in subjects given fructose than in those give glucose (P less than 0.05). The mean arterial concentration and splanchnic uptake of alanine were significantly higher in subjects given fructose than in postabsorptive controls, despite a significantly lower fractional extraction of alanine in the former (P less than 0.05). The mean arterial plasma levels of serine and ornithine were significantly lower in subjects receiving fructose than in postabsorptive controls (P less than 0.05). About half of the administered fructose or glucose was taken up in the splanchnic region, where approximately 15% was converted to CO2 and 10% to lactate. Half of the fructose taken up in the splanchnic region was converted to glucose released from the liver. The amount of hexose carbon remaining for hepatic synthesis of liquids in subjects given fructose was less than half of that of subjects given glucose. These studies demonstrate that fructose and glucose have divergent effects on amino acid metabolism and that during hypercaloric infusion of glucose (as with fructose), the human liver is a major site of lactate production.
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PMID:Effects of intravenously administered fructose and glucose on splanchnic amino acid and carbohydrate metabolism in hypertriglyceridemic men. 115 97

Tests carried out on strictly anaerobic and facultatively anaerobic strains of "corrodens" bacteria, showed that although these organisms are relatively inactive biochemically, differentiation can be made on the basis of tests that demonstrate reduction of nitrite, hydrolysis of urea and 1-naphthyl acetate, decarboxylation of lysine and ornithine, and sensitivity to certain selective agents included in culture medium. Plasma was found to be superior to serum in supporting the growth of all "corrodens" bacteria, and a combination of heated and unheated blood added to a nutrient base was shown to yield good growth. Comparative studies are reported with various species of Bacteroides, Haemophilus, Bordetella and related genera.
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PMID:A comparison of the biochemical activities of Bacteroides corrodens and Eikenella corrodens with those of certain other gramnegative bacteria. 116 23

Antipolyamine antibodies were produced following immunization of New Zealand white rabbits with thyroglobulin spermine conjugate, using multiple-site injection and macrophage-harvesting techniques. The antispermine antibody in a radioimmunoassay system cross-reacted with spermidine (22%), putrescine (1%), diaminopropane (6%), and cadaverine (0.16%). No reaction with L-lysine, ornithine, or histamine was noted. Using this antibody, the radioimmunoassay for direct determination of serum polyamines was developed. A sensitivity of 200 pg was achieved on human serum samples. This radioimmunoassay would appear to be a useful tool for the detection and monitoring of a variety of pathophysiological states associated with abnormal polyamine metabolism, i.e., cancer.
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PMID:Direct determination of polyamines in human serum by radioimmunoassay. 117 Sep 41


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