Search Results
Results 501 - 550 of 811
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Yokota S - - 1990
After administration of a hypolipidemic drug, MLM-160, to male rats, liver peroxisomes were studied by biochemical, cytochemical, and immunocytochemical methods. The activities of D-amino acid oxidase, glycolate oxidase, and urate oxidase increased 2 to 3-fold by the treatment. The increase of the oxidases was confirmed by immunoblotting analysis. By light ...
Parenti C - - 1990
The scavenging activity of some isosteric antiinflammatory heteoarylalkanoic acids with respect to oxygen-free radicals has been studied. All the compounds were found to inhibit the depolymerization of hyaluronic acid due to enzymatically or chemically generated hydroxyl radicals. The reduced consumption of oxygen by xanthine oxidase indicates a cotemporaneous phenomenon of ...
Atkinson M R - - 1990
The first enzymes of the histidine (hut) and proline degradative pathways, histidase and proline oxidase, could not be induced in Bacillus subtilis cells growing in glucose minimal medium containing a mixture of 16 amino acids. Addition of the 16-amino-acid mixture to induced wild-type cells growing in citrate minimal medium repressed ...
Petrie E C - - 1990
A modified synaptosomal superfusion apparatus is described which uses less than 10 micrograms of tissue per replicate sample and facilitates the routine separation of 3H-DA, 3H-DOPAC, and 3H-HVA. A flow rate of 1.5 ml/min allows superfusion without the use of reuptake or monoamine oxidase inhibitors. Superfusate samples are collected directly ...
Buffoni F - - 1990
The identification of the organic cofactor of pig plasma benzylamine oxidase is described. Acid hydrolysis of the enzyme in argon in the presence of phenylhydrazine (6 h at 115 degrees C in 0.027 M sulphuric acid) allowed the isolation of an adduct which was purified by HPLC and identified as ...
Alegría A E - - 1990
Semiquinones derived from anthraquinone-containing antitumor drugs (doxorubicin, daunorubicin and 4'-epidoxorubicin) were generated by the hypoxanthine/xanthine oxidase system in argon-saturated phosphate buffer (pH 7.4) in the presence of egg-yolk phosphatidylcholine multilamellar vesicles (MLVs) containing 1 mol% of a doxylstearic acid (DSA) isomer. The destruction of the electron spin resonance signal corresponding ...
Hommel R - - 1990
Fatty alcohol oxidase activities in Candida (Torulopsis) bombicola ATCC 22214, which produces large amounts of glycolipids consisting of omega- and (omega-1)-hydroxyfatty acids and a sugar moiety, occurred only in the microsomal fraction whether the cells had grown on n-alkanes, carbohydrates or a mixture of the two. High activities occurred in ...
Ohtsuka T - - 1990
NADPH oxidase activity in a membrane fraction prepared from phorbol 12-myristate 13-acetate (PMA)-stimulated guinea pig polymorphonuclear leukocytes (PMNL) was inhibited by positively charged myristylamine. The inhibitory effect of myristylamine was significantly suppressed by simultaneous addition of a negatively charged fatty acid, such as myristic acid. However, the suppression by myristylamine ...
Dupuis L - - 1990
The isozyme A of L-2-hydroxyacid oxidase is a peroxisomal flavoenzyme that catalyzes the oxidation of short-chain aliphatic L-2-hydroxyacids in many tissues of higher organisms. A new purification procedure allowed us to obtain a 1400-fold purified enzyme from chicken liver. The N-terminal amino acid of the polypeptide chain was found to ...
Lambás-Señas L - - 1990
In vivo voltammetry or microdialysis was used to monitor catecholaminergic metabolism in the C1 region of the ventrolateral medulla oblongata of anesthetized rats. In vivo voltammetry allowed the recording of a catechol oxidation current (CA.OC) peak in this region. This CA.OC was suppressed after inhibition of monoamine oxidase by pargyline ...
Srivastava V M - - 1990
Dicarboxylic acids and a few amino acids were found to support mitochondrial phosphorylation in A. ceylanicum. Anaerobiasis markedly reduced this activity. Maximum effect was observed on succinate supported phosphorylation which in anaerobic atmosphere yielded only 2% ATP compared to that in the presence of air. Known as well as candidate ...
Konno R - - 1990
Urine from mutant mice which lack D-amino-acid oxidase contained a large amount of D-alanine. The alanine content was not changed by changes in the dietary composition or by starvation. However, oral administration of an antibiotic, amoxicillin, decreased the urinary alanine to the normal level. These results suggest that the D-alanine ...
Nagasaki H - - 1990
A mutant mouse strain ddY/DAO- lacks D-amino acid oxidase activity and accumulates free neutral D-amino acids in its tissues. In this study, D-aspartate oxidase activity and D-aspartate content in the tissues of these mutant mice were compared with those of normal mice. No significant difference was observed, indicating that the ...
Rao V V - - 1990
L-Pipecolate oxidase, an enzyme that oxidizes L-pipecolic acid in the human liver has been demonstrated in the peroxisomal preparation. This enzyme oxidizes L-pipecolic acid with concomitant production of H2O2 in the peroxisome of the normal human liver. The immediate product of L-pipecolic acid oxidation has been identified as L-alpha-aminoadipate delta-semialdehyde. ...
Nishina Y - - 1990
Trigonelline, i.e., N-methylnicotinate, which has a zwitterionic structure similar to a substrate D-amino acid, is a useful active site probe for D-amino acid oxidase (DAO). The affinity of trigonelline for DAO in the deprotonated state at the enzyme bound FAD 3-imino group is higher than in the neutral state, contrary ...
Moret C - - 1990
The release of total tritium and 3H-5-hydroxytryptamine (5-HT) evoked by electrical stimulation from prelabelled rat hypothalamic slices was studied. Lysergic acid diethylamide (LSD) decreased white methiothepin increased both total tritium and 3H-5-HT overflow. The proportion of total tritium present as 3H-5-HT was equivalent under control conditions and in the presence ...
Vamecq J - - 1990
The present paper deals with the adaptation of the fluorometric measurement of H2O2 originally described by Guilbault et al. (1967, Anal. Chem. 39, 271) for the assay of the peroxisomal oxidation of D-amino acids, L-alpha-hydroxyacids, uric acid, and acyl-CoA esters. The present work essentially covers three facets: (i) the general ...
Lash L H - - 1990
S-(1,2-Dichlorovinyl)-L-homocysteine is a much more potent nephrotoxin than the corresponding cysteine S-conjugate S-(1,2-dichlorovinyl)-L-cysteine (A. A. Elfarra, L. H. Lash, and M. W. Anders (1986) Proc. Natl. Acad. Sci. USA 83, 2667-2671). The objective of the present experiments was to test the hypothesis that the increased toxicity of homocysteine S-conjugates may ...
Yoshida S - - 1990
Both oleic acid and oleate hydroperoxide at concentrations below 200 nmol/mg asolectin remarkably depressed the proton pumping of cytochrome c oxidase reconstituted into liposomes but did not affect the respiratory control ratio. The inhibitory effect was comparable to that of N,N'-dicyclohexylcarbodiimide. Oleate hydroperoxide in the vesicles was reduced by ferrocytochrome ...
Tan N H - - 1990
1. The intravenous median lethal doses (LD50), protease, phosphodiesterase, alkaline phosphomonoesterase, L-amino acid oxidase, acetylcholinesterase, phospholipase A, 5'-nucleotidase, hyauronidase and anticoagulant activities of fourteen samples of venoms from the four common species of krait (Bungarus caeruleus, Bungarus candidus, Bungarus multicinctus and Bungarus fasciatus) were examined. 2. The results indicate that ...
Robinson K - - 1990
The xanthine oxidase catalyzed oxidation of hypoxanthine was followed by monitoring the formation of uric acid at 290 nm. Inhibition of xanthine oxidase occurs in aqueous solutions of folic acid methotrexate and aminopterin. These compounds are known to dissociate upon exposure to ultraviolet light resulting in the formation of their ...
Tan N H - - 1990
1. The hemorrhagic, procoagulant, anticoagulant, protease, phosphodiesterase, alkaline phosphomonoesterase, L-amino acid oxidase, acetylcholinesterase, arginine ester hydrolase, phospholipase A, 5'-nucleotidase and hyaluronidase activities of 39 samples of venoms from 13 species (15 taxa) of Australian elapids were determined and the Sephadex G-75 gel filtration patterns for some of the venoms were ...
Webster K D - - 1989
L-Thiomorpholine-3-carboxylic acid (L-TMC) is a cyclized analog of S-(2-chloroethyl)-L-cysteine, which is cytotoxic in vitro and nephrotoxic in vivo. To determine whether L-TMC may play a role in S-(2-chloroethyl)-L-cysteine-induced toxicity, the cytotoxicity of L-TMC was studied in isolated rat kidney cells. L-TMC produced time- and concentration-dependent cytotoxicity. Probenecid, an inhibitor of ...
Dry I B - - 1989
The dependence of respiratory flux via the alternative pathway on the redox poise of the ubiquinone (Q) pool was investigated in soybean cotyledon mitochondria. A marked nonlinear relationship was observed between Q-pool reduction level and O2 uptake via the alternative oxidase. Significant engagement of the alternative pathway was not apparent ...
Osuga D T - - 1989
Amino acids and peptides have been attached to the C-6 hydroxyls of the galactose and the N-acetylgalactosamine by first oxidizing the C-6 hydroxyls to the aldehydes by galactose oxidase in the presence of small amounts of catalase, followed by reductive amination (alpha-amino group) in the presence of cyanoborohydride. The activity ...
Thiel C - - 1989
Bovine heart cytochrome-c oxidase was reconstituted in liposomes (asolectin) and the activity measured in the presence and absence of uncoupler at increasing concentrations of non-esterified fatty acids. Palmitic and stearic acids resulted in a decrease of about 40% in the respiratory control ratio at a concentration of 1 microM, when ...
Konno R - - 1989
Urine from mutant mice lacking D-amino-acid oxidase contained a large amount of alanine compared with that from normal mice. Urinary alanine of the mutant mice was sensitive to D-amino-acid oxidase. H.p.l.c. showed that about 94% of the urinary alanine had the D-configuration. These results suggest that D-amino-acid oxidase functions to ...
Stevens J L - - 1989
In this study, we have established the selectivity of inhibitors for rat kidney cysteine conjugate beta-lyase and L-alpha-hydroxy acid oxidase (L-amino acid oxidase) and have used these inhibitors to explore the relative roles of these two enzymes in the metabolism of nephrotoxic cysteine conjugates by rat kidney homogenate. In addition, ...
Goyal A - - 1989
Chlamydomonas in the resting phase of growth has an equal capacity of about 15 micromole O(2) uptake per hour per milligram of chlorophyll for both the cytochrome c, CN-sensitive respiration, and for the alternative, salicylhydroxamic acid-sensitive respiration. Alternative respiration capacity was measured as salicylhydroxamic acid inhibited O(2) uptake in the ...
Pilone Simonetta M - - 1989
The flavoprotein D-amino-acid oxidase was purified to homogeneity from the yeast Rhodotorula gracilis by a highly reproducible procedure. The amino acid composition of the protein was determined; the protein monomer had a molecular mass of 39 kDa and contained one molecule of FAD. The ratio between A274/A455 was about 8.2. ...
Baskaran S - - 1989
Bacteria present in the human gut may produce methylglyoxal--a cytotoxic substance in mammals. This was investigated by studying the activity of methylglyoxal synthase, which produces methylglyoxal from dihydroxyacetone phosphate, and methylglyoxal concentration in growth medium of various bacteria isolated from human faeces. Facultative and strictly anaerobic bacteria isolated from faeces ...
Miura R - - 1989
The interactions of competitive inhibitors, o-, m-, and p-fluorobenzoates, with porcine kidney D-amino acid oxidase (DAO) were studied by 19F-NMR spectroscopy. The 19F-signals of DAO-bound fluorobenzoates were observed as considerably broadened peaks. The chemical shifts, which are referenced to 20 mM NaF in 50 mM sodium phosphate, pH 7.0, were ...
Tsuda T - - 1989
The byproducts P-1 and P-2, which were produced during the synthesis of porcine secretin, were isolated in pure form from the crude secretin by HPLC. These were identified by a combination of amino acid analysis, enzymatic digestion, and isocratic or linear gradient reversed-phase (RP)-HPLC. The amino acid compositions of P1 ...
Ciolek E - - 1989
1. Liver catalase, D-amino acid oxidase, urate oxidase of Alytes obstetricans and Xenopus laevis (anuran amphibians) and fatty acyl-CoA oxidase of Alytes were present at all post-embryonic stages. 2. Catalase and D-amino acid oxidase activities increased during spontaneous metamorphosis of the two species. 3. During triiodothyronine-induced metamorphosis of Alytes larvae, ...
Lacroix C - - 1989
The plasma and urine pharmacokinetic parameters of pyrazinamide and of its metabolites (pyrazinoic acid, 5-hydroxy-pyrazinamide, 5-hydroxy-pyrazinoic acid and pyrazinuric acid) have been studied after a single oral dose of pyrazinamide 27 mg.kg-1 in 9 healthy subjects. Pyrazinamide was rapidly absorbed (tmax less than or equal to 1 h) and showed ...
Youdim M B - - 1989
The notion that monoamine oxidase (MAO) functions solely to inactivate neurotransmitter and other biogenic amines needs to be re-evaluated. It is now apparent that MAO-B is capable of oxidizing inert non-polar amines such as MPTP (N-methyl-4-phenyl-1,2,3,6, tetrahydropyridine) and milacemide (2-n-pentylaminoacetamide) into neuroactive substances giving rise to Parkinson inducing dopaminergic neurotoxin, ...
Shukla O P - - 1989
A Gram-negative, oxidase positive, polar flagellated rod, characterised as Pseudomonas stutzeri, has been isolated from sewage by enrichment culture on quinoline. The organism utilizes quinoline as the sole source of carbon, nitrogen and energy, and liberates UV absorbing and phenolic metabolites during its growth on quinoline. 2-Hydroxyquinoline, 2,8-dihydroxyquinoline, 8-hydroxycoumarin and ...
St Jules R - - 1989
A peroxide generating oxidase is demonstrated cytochemically in the peroxisomes of adult and larval Drosophila melanogaster, Oregon R and Rosy-506 strains. This enzyme activity is demonstrable using D-pipecolate or D-proline, but not L-proline, as substrate and is inhibited by kojic acid. Thus this enzyme shares cytochemical characteristics with vertebrate D-amino ...
Nagata Y - - 1989
The physiological role of D-amino acid oxidase was investigated by using mutant ddY/DAO- mice lacking the enzyme. Free D-amino acid concentrations in the mutant mice were significantly higher than those of control ddY/DAO+ mice in kidney, liver, lung, heart, brain, erythrocytes, serum and urine. The results suggest that the enzyme ...
Clarkson A B AB - - 1989
1. A comparative study of compounds which inhibit the respiration of the infective form of the protozoan parasite Trypanosoma brucei brucei, such as salicylhydroxamic acid, other substituted benzhydroxamic acid, esters of 2,3- and 3,4-dihydroxybenzoic acid and structurally related compounds, showed that they have a remarkable degree of selectivity for the ...
Shaw S - - 1989
Although folate deficiency and increased requirements for folate are observed in most alcoholics, the possibility that acetaldehyde generated from ethanol metabolism may increase folate catabolism has not been previously demonstrated. Folate cleavage was studied in vitro during the metabolism of acetaldehyde by xanthine oxidase, measured as the production of p-aminobenzoylglutamate ...
Subramanyam B - - 1989
1. 3,4,5,6-Tetrahydro-2H-azepine is an intermediate in the enzyme-catalyzed conversion of 1,6-diaminohexane to 6-aminohexanoic acid and its corresponding lactam, caprolactam, by mammalian liver aldehyde oxidase. 2. Identification of metabolites was based on analysis by gas chromatography-mass spectrometry and confirmed by comparison with the properties of authentic standards. 3. The results indicate ...
Konno R - - 1988
Thin-layer chromatography and amino acid analysis showed that urine of mutant ddY/DAO- mice lacking D-amino-acid oxidase activity contained more serine, proline, alanine and methionine than that of normal ddY/DAO+ mice. Among these four, an increase in alanine was conspicuous. However, the urinary levels of 11 other amino acids and glucose ...
Pellegrini-Giampietro D E - - 1988
The release of D-[3H]aspartate, [3H]noradrenaline, and of endogenous glutamate and aspartate from rat hippocampal slices was significantly increased when the slices were incubated with xanthine oxidase plus xanthine to produce superoxide and hydroxyl free radicals locally. Allopurinol, a specific xanthine oxidase inhibitor, the hydroxyl-radical scavenger D-mannitol, or the superoxide-radical scavenger ...
Morpurgo L - - 1988
The carbonyl cofactor of bovine serum amine oxidase, recently identified as pyrroloquinoline quinone [Ameyama, Hayashi, Matsushita, Shinagawa & Adachi (1984) Agric. Biol. Chem. 48, 561-565; Lobenstein-Verbeek, Jongejan, Frank & Duine (1984) FEBS Lett. 170, 305-309], reacts stoichiometrically and irreversibly with hydrazides of phenylacetic acid and of benzoic acid. With the ...
Ding X X - - 1988
Two forms of cytochrome P-450, designated P-450NMa and P-450NMb, were purified to electrophoretic homogeneity from rabbit nasal microsomes. The purified cytochromes, which contained 14-16 nmol of P-450/mg of protein, exhibited apparent monomeric molecular weights of 49,500 and 51,000, respectively. As indicated by several criteria, including the amino acid composition, absorption ...
Amit N - - 1988
Whether or not cytochrome b-559 is a necessary component of NADPH oxidase activity in neutrophils is still controversial. In highly purified plasma membranes isolated from resting neutrophils and lacking cytochrome b, addition of arachidonic acid induced an NADPH oxidase activity. This activity was similar to that of plasma membranes isolated ...
Dale M P - - 1988
Cardiolipin derivatives retaining the free hydroxyl on the polar head group were synthesized. With the use of a tetrahydropyranyl ether to protect this hydroxyl, fatty acyl substitutions were made at both of the 2-positions of cardiolipin (CL). The disubstituted derivatives were obtained in high yields. The stimulation of delipidated cytochrome ...
Nagami M - - 1988
Both Km and Vmax values of cytochrome c oxidase for cytochrome c were elevated in oleic acid-incorporated mitochondria, whereas the amount of oleic acid incorporated into submitochondrial particles was smaller than that into mitochondria and the fatty acid had little effect on the enzyme activity. The degree of change in ...
Labonia N - - 1988
Bovine heart cytochrome c oxidase was reconstituted in phospholipid vesicles, and the effect of different non-esterified fatty acids (NEFA) was studied on its proton pump and on the proton permeability of the vesicles. Neither parameter appeared to be affected by concentrations of NEFA known to uncouple oxidative phosphorylation (10 microM). ...
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