Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:4.1.1.17 (ornithine decarboxylase)
6,351 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of this study was to examine the activity and associated kinetic parameters of epidermal protein kinase C (PKC) following stimulation by sn-1,2-dioctanoylglycerol (DIC8) or 12-O-tetradecanoylphorbol-13-acetate (TPA) and to examine the relationship between levels of epidermal PKC activity and the induction of ornithine decarboxylase by these agents, utilizing various stocks and strains of mice. Importantly, the mouse strains and stock used in this study have known differing susceptibilities to undergo TPA-induced tumor promotion: the CD-1 stock and the DBA/2 strain (both sensitive to TPA-induced tumor promotion) and the C57BL/6 strain (resistant to TPA-induced tumor promotion). TPA-stimulated protein kinase C activity was measured in the 10(5)g supernatant fraction of epidermal homogenates using lysine-rich histone as a phosphate acceptor substrate. The maximal velocities for TPA-stimulated epidermal PKC activity in CD-1, DBA/2 and C57BL/6 were 0.28, 0.29 and 0.27 nmol PO4-histone/mg 10(5)g protein/min, respectively. TPA-stimulated epidermal PKC from CD-1, DBA/2 and C57BL/6 had similar theoretical Vmax values and the apparent concentrations of TPA yielding half-maximal stimulation of PKC were also similar. DiC8-stimulated PKC activity to a greater Vmax; however, the concentration required to yield half-maximal stimulation of PKC was one thousand times greater than that of TPA. There were no strain differences in these parameters when the enzyme was stimulated with DiC8. Thus, the levels of epidermal PKC activity in CD-1, DBA/2 and C57BL/6 mice exhibit no strain differences when stimulated by TPA or DiC8 using lysine-rich histone as a phosphate acceptor substrate. Since sn-1,2-diacylglycerols are known effective inducers of epidermal ornithine decarboxylase (ODC) activity, the induction of epidermal ODC was examined in each mouse strain 5 h after topical application of 2 nmol TPA, 5 nmol TPA or 2.5 mumol DiC8. After topical treatment with TPA, C57BL/6 demonstrated an unexpected 2- and 4-fold increase in ODC activity over CD-1 and DBA/2 mice. After treatment with DiC8, C57BL/6 demonstrated a 6- and 10-fold increase in ODC activity over CD-1 and DBA/2, respectively. Thus, the resistant strain (C57BL/6) demonstrated a 'hyperinducibility' of epidermal ODC activity by TPA or DiC8. The time course for the induction of epidermal ODC was examined in each strain, and at every time point measured (3-15 h), the C57BL/6 strain exhibited this 'hyperinducibility' of ODC relative to the other strains. Epidermal DNA synthesis was stimulated to a similar extent in C57BL/6 and CD-1 mice.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Comparison of epidermal protein kinase C activity, ornithine decarboxylase induction and DNA synthesis stimulated by TPA or dioctanoylglycerol in mouse strains with differing susceptibility to TPA-induced tumor promotion. 270 40

Spermidine was detected as the major polyamine of Ancylostoma ceylanicum as well as Nippostrongylus brasiliensis. Spermine was present in lower amounts whereas the level of putrescine was even less. S-Adenosylmethionine decarboxylase, a rate-limiting enzyme in the biosynthetic pathway of polyamines, was demonstrated at low levels in both parasites. Decarboxylation of lysine and arginine was absent or negligible and that of ornithine questionable, as the enzyme activity was not inhibited by alpha-difluoromethylornithine while RMI 71,645, an irreversible inhibitor of ornithine aminotransferase, strongly inhibited the liberation of CO2 from ornithine. High activity of ornithine aminotransferase was observed in both the parasites and may interfere with the assay for ornithine decarboxylase. Adults of A. ceylanicum were found to rapidly take up spermidine and spermine from incubation medium while uptake of putrescine was very low. These results indicate that hookworms depend on uptake and interconversion rather than de novo synthesis for their polyamine requirement.
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PMID:Polyamine metabolism in Ancylostoma ceylanicum and Nippostrongylus brasiliensis. 272 92

In this paper, we describe a reduced sequence of identification that includes T-mod medium, a selective and differential isolation medium which allows accurate presumptive identification of the most common gram-negative bacteria encountered in urine samples. The present study, performed on bacteria isolated from 1,762 independent urine samples, has shown that a few selected tests (lysine and ornithine decarboxylase, urease and trehalose fermentation tests) improve the identification accuracy of T-mod, making it possible both to identify the less frequent species and to prevent some misidentifications of Klebsiella pneumoniae and Proteus mirabilis. The proposed work flow agreed with conventional identification protocols to a 99.3% extent and allowed identification of 87.4% of the isolates directly from the primary plate, 11.4% after 1 to 3 additional tests, and 1.2% after an identification gallery.
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PMID:T-mod pathway, a reduced sequence for identification of gram-negative urinary tract pathogens. 276 51

Effects were examined of inanition, dietary aflatoxin (2.5 mg/kg), and dietary supplements of threonine, lysine, and arginine on the activities of renal arginase and hepatic ornithine decarboxylase and on the accumulation of polyamines in liver and brain of 24 or 26-day-old broiler cockerels. Aflatoxicosis and inanition lowered the activity of renal arginase by 58 and 37%, respectively. Supplemental dietary threonine (.4%) did not suppress the activity of renal arginase, while fortification of diets of controls with lysine (.53%), but not diets containing aflatoxin, elevated the activity of renal arginase. Supplements of dietary lysine and/or arginine did not influence the hepatic content of putrescine but lowered the concentrations of spermidine and spermine. Aflatoxicosis, but not inanition, increased the activity of hepatic ornithine decarboxylase (ODC; 22-fold), increased hepatic concentrations of putrescine and spermidine, but decreased spermine concentrations. The elevation of hepatic ODC, putrescine, and the ratio of spermidine to spermine parallels the enlargement of the liver caused by aflatoxicosis. Cadaverine and putrescine were not detected in avian brain, while cerebral concentrations of spermidine and spermine were not altered by aflatoxin, inanition, or by supplements of dietary lysine, arginine, or both lysine and arginine.
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PMID:Influence of avian aflatoxicosis on the synthesis of polyamines. 311 52

A reversed-phase high-performance liquid chromatography method, with L-proline and copper as chiral mobile phase, is described for the enantiomeric resolution of various alpha-substituted ornithine and lysine analogs. Although ornithine gives no separation with the chiral eluant used, excellent resolutions are obtained for various alpha-alkyl-, alpha-halogenomethyl-, alpha-vinyl-, and alpha-ethynyl-substituted ornithines. Similar separations are also observed for the dehydroornithine and lysine analogs. Gas chromatography on a chiral stationary phase, Chirasil-Val, allows the resolution of the ornithine and lysine analogs after derivatization into the monofluoroacyl derivatives of their corresponding lactams. No resolution or only a poor resolution is obtained by GC on Chirasil-Val for the dehydroornithine analogs as their di-N-perfluoroacyl alkyl esters. The chiral eluant HPLC procedure is easily scaled up for the semipreparative resolution of several ornithine analogs, i.e., alpha-fluoromethylornithine, alpha-difluoromethylornithine, alpha-chlorofluoromethylornithine, and alpha-fluoromethyldehydroornithine, which are known as potent ornithine decarboxylase inhibitors in vitro and in vivo.
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PMID:Resolution of the enantiomers of various alpha-substituted ornithine and lysine analogs by high-performance liquid chromatography with chiral eluant and by gas chromatography on Chirasil-Val. 311 32

Experiments were conducted to determine the effect of dietary lysine on hepatic and renal polyamine synthesis in the chick. High arginine-requiring (HA) and low arginine-requiring (LA) strains were used, with differences in arginine requirements being due, in part, to differences in renal arginase activity. Arginine requirements were 1.2 and 0.9% for the HA strain and LA strain, respectively. A total of 96 chicks (16 per diet, 48 per strain) were fed a crystalline amino acid diet containing requirement concentrations of arginine and 0.95, 1.40 or 1.85% lysine for 2 wk. Hepatic arginase activity was unaffected by dietary lysine in both strains, whereas hepatic ornithine decarboxylase (ODC) activity fell with increased dietary lysine in the LA strain only. Increasing dietary lysine significantly increased renal arginase activity but reduced renal ODC activity in the HA strain only. Increasing dietary lysine also caused decreased renal concentrations of arginine, whereas lysine and ornithine concentration increased in both strains. Concentrations of putrescine also rose. It was concluded that excess dietary lysine increased renal concentrations of ornithine due to induction of arginase. This accumulation of polyamine precursors resulted in increased concentrations of putrescine despite feedback inhibition of ODC.
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PMID:Effect of dietary lysine on polyamine synthesis in the chick. 311 98

Gastrin injection and refeeding fasted rats are effective trophic stimuli for the oxyntic gland mucosa of the stomach. Neither stimulus increases detectable ornithine decarboxylase (ODC) activity in the tissue. Difluoromethylornithine (DFMO), a potent inhibitor of ODC, blocks the mucosal growth response, indicating that ODC activity is necessary for growth. Elevated levels of spermidine and spermine are detectable in the mucosa after gastrin administration. Using a highly specific, polyclonal antiserum to ODC, we determined that the enzyme is present in oxyntic gland mucosa confined to a narrow band of cells at the base of the gastric pits and openings of the glands. In antral mucosa, ODC is present throughout the lower 20% of the mucosa, which consists of the necks and pyloric glands. Using antiserum dilution techniques, we show that gastrin administration increases immunoreactive ODC in the oxyntic gland area but not in the antral mucosa, where it has no trophic effect. Elevated cellular content of ODC is apparent within 2 h after injection of gastrin, peaks at 4 h, and declines to basal levels by 12 h. Gastrin-stimulated increase in ODC is confined to the narrow band of cells in which low levels of the enzyme protein were detected in control animals. The decarboxylating activity detectable in oxyntic gland mucosal extracts is not inhibited by administration of DFMO or cycloheximide, each of which inhibits ODC activity in other tissues. Addition of unlabeled lysine to the decarboxylation assay reaction of oxyntic gland mucosa extract inhibits the decarboxylation of radiolabeled ornithine substrate. Thus it is likely that the stomach possesses nonspecific decarboxylase activity, which accounts for most of the measured activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Gastric mucosal ornithine decarboxylase: localization and stimulation by gastrin. 313 18

The lysA gene encodes meso-diaminopimelate (DAP) decarboxylase (E.C.4.1.1.20), the last enzyme of the lysine biosynthetic pathway in bacteria. We have determined the nucleotide sequence of the lysA gene from Pseudomonas aeruginosa. Comparison of the deduced amino acid sequence of the lysA gene product revealed extensive similarity with the sequences of the functionally equivalent enzymes from Escherichia coli and Corynebacterium glutamicum. Even though both P. aeruginosa and E. coli are Gram-negative bacteria, sequence comparisons indicate a greater similarity between enzymes of P. aeruginosa and the Gram-positive bacterium C. glutamicum than between those of P. aeruginosa and E. coli enzymes. Comparison of DAP decarboxylase with protein sequences present in data bases revealed that bacterial DAP decarboxylases are homologous to mouse (Mus musculus) ornithine decarboxylase (E.C.4.1.1.17), the key enzyme in polyamine biosynthesis in mammals. On the other hand, no similarity was detected between DAP decarboxylases and other bacterial amino acid decarboxylases.
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PMID:Pseudomonas aeruginosa diaminopimelate decarboxylase: evolutionary relationship with other amino acid decarboxylases. 314 46

The amounts of normal and compensatory polyamines of polyamine-requiring Escherichia coli mutants grown in the absence of polyamines were determined. Although aminopropylcadaverine, a compensatory polyamine, was synthesized by MA135 (speB) and DR112 (speA speB), no aminopropylcadaverine or only small amounts of aminopropylcadaverine were synthesized by EWH319 (speA speB speC speD) and MA261 (speB speC), respectively. The average mass doubling times of MA135, DR112, MA261, and EWH319 grown in the absence of polyamines were 113, 105, 260, and 318 min, respectively. The correlation of these values with the sum of spermidine plus aminopropylcadaverine suggested that aminopropylcadaverine is important for cell growth in the presence of limiting amounts of normal polyamines. This hypothesis is supported by the results of aminopropylcadaverine stimulation of the in vitro synthesis of polyphenylalanine and MS2 RNA replicase and of its stimulation of the growth of MA261. For the following reasons, it was concluded that aminopropylcadaverine was synthesized preferentially from cadaverine made by ornithine decarboxylase: aminopropylcadaverine was synthesized in relatively large amounts in cells (MA135 and DR112) which possess ornithine decarboxylase; ornithine decarboxylase catalyzed the decarboxylation of lysine in vitro, and the in vivo formation of aminopropylcadaverine was inhibited by an inhibitor of ornithine decarboxylase.
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PMID:Formation of a compensatory polyamine by Escherichia coli polyamine-requiring mutants during growth in the absence of polyamines. 351 74

In 1983, the vernacular name Enteric Group 77 was coined for a group of strains that had been referred to our laboratory as "possible Vibrio cholerae except for gas production." By DNA-DNA hybridization (hydroxyapatite, 32P), 8 of 10 strains of Enteric Group 77 were very highly related to the labeled strain 1169-83 (74 to 100% at 60 degrees C and 75 to 100% at 75 degrees C; percent divergence, 0.0 to 2.5). Type strains of six other Aeromonas species were 45 to 66% related (60 degrees C) to strain 1169-83, but type strains of 27 Vibrio species were only 2 to 6% related. The name Aeromonas veronii is proposed for the highly related group of nine strains formerly known as Enteric Group 77. The type strain is designated as ATCC 35604 (CDC 1169-83). Strains of A. veronii grew well at 36 degrees C and had positive reactions at this temperature for indole, methyl red, Voges-Proskauer, citrate, lysine and ornithine decarboxylases, DNase, lipase, and motility; the strains had negative reactions for arginine decarboxylase, H2S, urea, and malonate. The following sugars were fermented: D-glucose (acid and gas), cellobiose (seven of nine strains), D-galactose, maltose, D-mannitol, D-mannose, alpha-methyl-D-glucoside (eight of nine strains), salicin, sucrose, and trehalose. The following sugars were not fermented: adonitol, L-arabinose, D-arabitol, dulcitol, erythritol, myo-inositol, lactose, raffinose, L-rhamnose, D-sorbitol, and D-xylose. The positive ornithine decarboxylase reaction differentiates A. veronii from other Aeromonas species. The antibiogram of A. veronii is typical of other Aeromonas strains (resistance to ampicillin and carbenicillin and susceptibility to most other agents). A. veronii strains were isolated from three clinical sources: respiratory secretions of four victims of drowning or near drowning in fresh water (probably not clinically significant); infected wounds of two patients previously exposed to fresh water (unknown clinical significance); and stools from three patients with diarrhea (probably clinically significant).
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PMID:Aeromonas veronii, a new ornithine decarboxylase-positive species that may cause diarrhea. 358 25


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