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)

Arginine decarboxylase which makes its appearance in Lathyrus sativus seedlings after 24 h of seed germination reaches its highest level around 5-7 days, the cotyledons containing about 60% of the total activity in the seedlings at day 5. The cytosol enzyme was purified 977-fold from whole seedlings by steps involving manganese chloride treatment, ammonium sulphate and acetone fractionations, positive adsorption on alumina C-gamma gel, DEAE-Sephadex chromatography followed by preparative disc gel electrophoresis. The enzyme was shown to be homogeneous by electrophoretic and immunological criteria, had a molecular weight of 220,000 and appears to be a hexamer with identical subunits. The optimal pH and temperature for the enzyme activity were 8.5 and 45 degrees C respectively. The enzyme follows typical Michaelis-Menten kinetics with a Km value of 1.73 mM for arginine. Though Mn2+ at lower concentrations stimulated the enzyme activity, there was no dependence of the enzyme on any metal for the activity. The arginine decarboxylase of L. sativus is a sulfhydryl enzyme. The data on co-factor requirement, inhibition by carbonyl reagents, reducing agents and pyridoxal phosphate inhibitors, and a partial reversal by pyridoxal phosphate of inhibition by pyridoxal-HCl suggests that pyridoxal 5'-phosphate is involved as a co-factor for the enzyme. The enzyme activity was inhibited competitively by various amines including the product agmatine. Highest inhibition was obtained with spermine and arcain. The substrate analogue, L-canavanine, homologue L-homoarginine and other basic amino acids like L-lysine and L-ornithine inhibited the enzyme activity competitively, homoarginine being the most effective in this respect.
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PMID:Arginine decarboxylase from Lathyrus sativus seedlings. Purification and properites. 0 Dec 52

Arginine and methionine transport by Aspergillus nidulans mycelium was investigated. A single uptake system is responsible for the transport of arginine, lysine and ornithine. Transport is energy-dependent and specific for these basic amino acids. The Km value for arginine is 1 X 10(-5) M, and Vmax is 2-8 nmol/mg dry wt/min; Km for lysine is 8 X 10(-6) M; Kt for lysine as inhibitor of arginine uptake is 12 muM, and Ki for ornithine is mM. On minimal medium, methionine is transported with a Km of 0-I mM and Vmax about I nmol/mg dry wt/min; transport is inhibited by azide. Neutral amnio acids such as serine, phenylalanine and leucine are probably transported by the same system, as indicated by their inhibition of methionine uptake and the existence of a mutant specifically impaired in their transport. The recessive mutant nap3, unable to transport neutral amino acids, was isolated as resistant to selenomethionine and p-fluorophenylanine. This mutant has unchanged transport of methionine by general and specific sulphur-regulated permeases.
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PMID:Basic and neutral amino acid transport in Aspergillus nidulans. 0 66

Aphids transmitted poly-L-ornithine (PLO)-treated tobacco mosaic virus (TMV) when given acquistion and inoculation access periods as brief as 30 s and 2 min, respectively; the ability to transmit was lost within 90 min. Aphids without claws were able to transmit the virus. Transmission thus seems similar to that of nonpersistent viruses. The ratio of virus to polyamino acid, as well as the KCl concentration, markedly affected transmission. Transmission was best from mixtures which contained 250 mug/ml TMV, 2-5 MUG/ML PLO (mol. wt. 120000) and 0-6 M-KCl. A similar mixture favoured transmission when poly-L-lysine (mol. wt. 85000) was substituted for PLO, but with poly-L-lysine (mol. wt. 30 000) it was necessary to decrease the KCl to 0-3 M to obtain transmission. Less KCl (0-08 to 0-24 M) also favoured aphid transmission of PLO-treated potato virus X and tobacco rattle virus. PLO-treated TMV ultracentrifuged in the presence of, and resuspended in, 0-6 M-KCl remained aphid transmissible while PLO-treated virus in 2 M-DCl, which favours greater dissociation of the virus-PLO complex, was transmissible neither before nor after sedimentation by ultracentrifuging, and resuspension in 0-6 M-KCl. these results show that transmissibility is not due to a permanent alteration of the virus by PLO and indicate that the formation of a TMV-PLO complex is required for transmission. Sequential acquisition experiments suggest that PLO may act by binding TMV to receptor sites in aphids. However, the possibility that PLO affects the infection process was not ruled out.
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PMID:Polyamino acid induced aphid transmission of plant viruses. 0 67

The two tripeptide antibiotics L-2-amino-4-methylphosphinobutyryl-alanyl-alanyl-alanine (L-phosphinothricyl-alanyl-alanine) and L-(N5-phosphono)methionine-S-sulfoximinyl-alanyl-alanine, both inhibitors of the glutamine synthetase, are transported into the cell of Escherichia coli K 12 via the oligopeptide transport system. The uptake by this system is proved first of all by cross-resistance with tri-L-ornithine using oligopeptide-transport-deficient mutants, and secondly by antagonism tests demonstrating competitive reversal of the action of the antibiotic by several peptides which have been shown to be transported via the oligopeptide transport system, e.g. tri-L-alanine, tetra-L-alanine, tri-L-lysine, tri-L-serine, tri-glycine, glycyl-glycyl-L-alanine and the synthetic tripeptide L-azadenyl-aminohexanoyl-alanyl-alanine. On the other hand, there is no effect on the action of the antibiotic in antagonism tests with compounds which use different transport systems, such as L-alanyl-alanine, L-lysyl-lysine, glutathione and the synthetic amino acid azaadenylaminohexanoic acid, i.e. 2-amino-6-(7-amino-3H-v-triazolo-[4,5-d]-pyrimidin-3-yl)hexanoic acid. Another inhibitor of the glutamine synthetase, L-methionine-S-dioxide (methioninesulfone) could be converted into a tripeptide form by linkage to L-alanyl-alanine analogously to the tripeptide antibiotics described above. Whereas the free L-methionine-S-dioxide seems to be transported via the methionine transport system, the tripeptide form is transported via the oligopeptide transport system. Thus, this glutamine synthetase inhibitor can be taken up by the cell via two different transport mechanisms. Our results indicate that this could provide a synergistic effect. The syntheses of the new tripeptides L-azaadenylaminohexanoyl-alanyl-alanine and L-methionine-S-dioxidyl-alanyl-alanine were performed by dicyclohexylcarbodiimide couplings of the unusual N-protected L-alpha-amino acids azaadenylaminohexanoic acid and L-methionine-S-dioxide to L-alanyl-alanine-tert-butyl ester followed by common deprotection steps. Tri-L-ornithine was synthesized without carboxyl protection via two successive couplings of hydroxybenzotriazol esters of Nalpha-butoxycarbonyl-Ndelta-benzyloxycarbonyl-L-ornithine.
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PMID:On the transport of tripeptide antibiotics in bacteria. 0 11

When tris-HCL was used as the buffer for inoculation of tomato protoplasts with tobacco mosaic virus, a greater proportion became infected than when phosphate was used. Using 0-05 M-tris-HCl buffer, pH 8-0, in the presence of poly-L-ornithine or poly-D-lysine, 50 to 80 % infection was obtained.
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PMID:The use of tris-HCl buffer for inoculation of tomato protoplasts with tobacco mosaic virus. 1 23

18 free amino-acids have been valuated in a group of patients recovering from myocardial infarction dating more than one year back and in another group of healthy active athlets. In the group of the ill persons the mean values of the following amino-acids were significantly higher: Arginine, asparagine-acid, phenylalanine, valine, lysine, serine, threonine, leucine, proline and tyrosine. While in the group of the healthy persons the following amino - acids proved to have significantly higher values: alpha -- aminobutter-acid, glycine and cystine. No significant differences between the mean values of both groups were to be found of the following amino - acids: Alanine, methionine, ornithine, isoleucine and histidine. In the group of the patients correlations of the free amino acids to both serumlipids and blood -- glucose could be calculated with significant results in a certain number of amino-acids. The results may suppose that the changes in the metabolism of atherosclerotic patients do not only effect the lipids and carbohydrates, but as well the free amino-acids.
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PMID:[Free amino-acids of the plasma in atherosclerotic patients (author's transl)]. 1 52

Kinetics of sensitization of chimpanzee cell sheets to transfection by poliovirus RNA was determined for 5 basic polypeptides. With basic olypeptide hydrobromide at 100 microng/ml, initial sensitization rate was faster for poly-L-ornithine of average molecular weight (AMW) 15500 than of AMW 105000, and much faster for poly-L-lysine of AMW 1700 than of AMW 140000. Desensitization phases were observed with the 2 shorter polypeptides. Sensitization was much faster and sensitivity maxima were considerably higher for the polyornithines than for the polylysines. Poly-D-lysine of AMW 160000 sensitized cells slightly faster than poly-L-lysine of AMW 140000, but gave about the same sensitivity maximum. Analysis of the slow cell sensitization by poly-L-lysine of AMW 140000 revealed 2 steps: a fast step 1 (attachment) and a slow step 2 (processing).
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PMID:Influence of polypeptide molecular and side chain lengths and of side chain steric location on the kinetics of basic polypeptide-induced sensitization of primate cells to transfection. 1 33

An enzyme which catalyzes the transfer of the gamma-phosphate from GTP onto 5-hydroxylysine was partially purified from rat kidney cortex by means of acid precipitation and DEAE-Sephadex A-50 column chromatography. The enzyme activity was assayed by measuring the transfer of [32P] from gamma-[32P]-GTP to materials not adsorbed by charcoal. This partially purified enzyme showed essentially no GTP phosphohydrolase activity and an optimal pH of 8.0. An apparent Km of about 23.8 mumol/1 was obtained with respect to 5-hydroxylysine. Mg2+ was required for the activity of this enzyme. Ethanolamine, L-lysine, L-ornithine and choline inhibited the enzyme but L-threonine, L-serine and hydroxy-L-proline did not. None of these compounds severed as substrate for this enzyme.
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PMID:Guanosine triphosphate: 5-hydroxylysine phosphotransferase in rat kidney cortex. 1 39

The research of lysine, ornithine and arginine decarboxylases has been made for 50 strains of fluorescent Pseudomonas (P. aeruginosa, P. fluorescens, P. putida). By thin layer chromatography, all the strains of Pseudomonas aeruginosa and the fifth of the strains of P. putida had lysine decarboxylase activity at alcaline pH (optimal pH 8) ; Pseudomonas fluorescens did not produce this decarboxylase. Arginine and ornithine decarboxylase are absent for all the strains of fluorescent Pseudomonas.
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PMID:[Lysine decarboxylase in Pseudomonas aeruginosa]. 1 33

The conformational properties of cupric complexes of poly(L-lysine), poly(L-ornithine), and poly(L-diaminobutyric acid) have been investigated by potentiometric, visible and UV absorption, and circular dichroism (CD) techniques. The three polymers form two kinds of complexes stable at pH less than 8.5 (type I complexes) and at pH less than 8.5 (type II complexes). It has been found that in the low pH complexes of poly(L-diaminobutyric acid) at least one deprotonated amido nitrogen is coordinated to cupric ions. Type II complexes involve always amide nitrogens in the coordination sphere of Cu(II). Evidence is presented that the structure of such complexes is not compatible with the alpha-helical conformation of the peptide backbone.
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PMID:Metal complexes of poly(alpha-amino acids). A potentiometric and circular dichroism investigation of Cu(II) complexes of poly(L-lysine), poly(L-ornithine), and poly(L-diaminobutyric acid). 1 53


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