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Smit Martha S - - 2005
alpha,omega-Dicarboxylic acid accumulation from alkanes and alkane degradation intermediates was investigated using Yarrowia lipolytica wild type strain W29 as well as a double, a triple and a quadruple POX-deleted strains. Six genes, POX1 through POX6, encode six acyl-CoA oxidase isozymes in Y. lipolytica. All the strains accumulated dodecanedioic acid (5-20 ...
Güllçin Ilhami - - 2005
Polyphenol oxidase (PPO) of nettle (Urtica dioica L.) was extracted and purified through (NH4)2SO4 precipitation, dialysis, and CM-Sephadex ion-exchange chromatography and was used for its characterization. The PPO showed activity to catechol, 4-methylcatechol, L-3,4-dihydroxyphenylalanine (L-DOPA), L-tyrosine, p-cresol, pyrogallol, catechin and trans-cinnamic acid. For each of these eight substrates, optimum conditions ...
Jeyaseelan M - - 2005
Some physiological and biochemical changes were measured between embryogenic and non-embryogenic callus obtained from Cardiospermum halicacabum. Combination of auxin with cytokinin was more favourable for high amount of callus formation. 2,4-D played a key role in triggering somatic embryo formation. Embryogenic callus had more total carbohydrate and starch contents, total ...
Xu Jin-Wen - - 2005
Caffeic acid, a dietary phenol from coffee, fruits and vegetables, is an efficient antioxidant. However, little is known about its anti-oxidative mechanism in the modulation of fundamental cellular processes. In this study, we investigated whether caffeic acid regulates Rac1 GTPase activity, a partner of NADPH oxidase. Our results showed that ...
Pan Dawei - - 2005
An amperometric glucose biosensor is developed that is based on immobilization of glucose oxidase (GOD) in a composite film of poly(o-aminophenol) (POAP) and carbon nanotubes (CNT), which are electrochemically co-polymerized at a gold (Au) electrode. Because of the high surface per volume ratio and excellent electrical conductivity of CNT, the ...
Weinberger Florian - - 2005
Gametophytes of the marine alga Chondrus crispus are more resistant than tetrasporophytes to infection by the filamentous endophytic alga Acrochaete operculata. It has been shown recently that carrageenan oligosaccharides from the resistant gametophytic generation of C. crispus stimulate the secretion of L-asparagine (L-Asn) by the endophyte and that the host ...
Panoutsopoulos Georgios I - - 2005
Phenylacetaldehyde is formed when the xenobiotic and biogenic amine 2-phenylethylamine is inactivated by a monoamine oxidase-catalyzed oxidative deamination. Exogenous phenylacetaldehyde is found in certain foodstuffs such as honey, cheese, tomatoes, and wines. 2-Phenylethylamine can trigger migraine attacks in susceptible individuals and can become fairly toxic at high intakes from foods. ...
Dai Xinhua - - 2005
The synthetic molecule sirtinol was shown previously to activate the auxin signal transduction pathway. Here we present a combination of genetic and chemical approaches to elucidate the action mechanisms of sirtinol in Arabidopsis. Analysis of sirtinol derivatives indicated that the "active moiety" of sirtinol is 2-hydroxy-1-naphthaldehyde (HNA), suggesting that sirtinol ...
Crichton Paul G - - 2005
Activity of the plant mitochondrial alternative oxidase (AOX) can be regulated by organic acids, notably pyruvate. To date, only two well-conserved cysteine residues have been implicated in this process. We report the functional expression of two AOX isozymes (Sauromatum guttatum Sg-AOX and Arabidopsis thaliana At-AOX1a) in Schizosaccharomyces pombe. Comparison of ...
Yoshida Nobuyuki - - 2005
Fructosyl-amino acid oxidase (FAOD)-reactive fraction (FRY) was found in commercial yeast extract. FRY showed very hydrophilic property and was adsorbed to phenylboronate silica gel, indicating that it contained the Amadori compound. TLC and amino acid analyses revealed that glucosone, lysine, and arginine were produced from FRY after incubation with FAOD. ...
Panoutsopoulos Georgios - - 2005
BACKGROUND/AIMS: Homovanillamine is a biogenic amine that it is catalyzed to homovanillyl aldehyde by monoamine oxidase A and B, but the oxidation of its aldehyde to the acid derivative is usually ascribed to aldehyde dehydrogenase and a potential contribution of aldehyde oxidase and xanthine oxidase is usually ignored. METHODS: The ...
Tishkov V I - - 2005
D-Amino acid oxidase (DAAO) is a FAD-dependent enzyme that plays an important role in microbial metabolism, utilization of endogenous D-amino acids, regulation of the nervous system, and aging in mammals. DAAO from yeasts Rhodotorula gracilis and Trigonopsis variabilis are used to convert cephalosporin C into 7-aminocephalosporanic acid, the precursor of ...
Fogliani Bruno - - 2005
Chemical study of Cunonia macrophylla, a New Caledonian Cunoniaceae, based on bioactive effects of a crude methanol extract of the leaves, detected bioactive tannins for the first time in this plant family. These ellagitannins have been identified as ellagic acid-4-O-beta-D-xylopyranoside (6), mallorepanin (3), mallotinic acid (1) along with corilagin (2), ...
Cetinus Ercan - - 2005
Alkoptunuria is an inherited autosomal recessive metabolic disorder which is caused by the lack of homogentisic acid-oxidase enzyme. It is associated with various systemic abnormalities and related to the deposition of homogentisic acid pigment in connective tissues. These pigmentary changes are termed "ochronosis". We describe two patients with ochronotic arthritis ...
Lahey Katherine A - - 2004
Colletotrichum acutatum infects citrus petals and induces premature fruit drop and the formation of persistent calyces. The accumulation of hormones and other growth regulators, and differential gene expression in affected flowers and young fruit, was examined following fungal infection. Ethylene evolution increased threefold and indole-3-acetic acid (IAA) accumulation was as ...
Zhang Hongmin - - 2004
The antibacterial actions of two amino acid oxidases, a D-amino acid oxidase from hog kidney and a L-amino acid oxidase from the venom of Agkistrodon halys, were investigated, demonstrating that both enzymes were able to inhibit the growth of both Gram-positive and Gram-negative bacteria, and that hydrogen peroxide, a product ...
Stefan Raluca-Ioana - - 2004
A sequential injection analysis/amperometric biosensor system is proposed for the enantioselective analysis of the S-enantiomer of enalapril, ramipril and pentopril. The amperometric biosensor used as detector in the sequential injection analysis was designed by immobilization of l-amino acid oxidase in carbon paste. The proposed SIA system can be utilized reliably ...
Narimatsu Shizuo - - 2004
The effects of the substitution of amino acid residues at positions 43 and 45 of rat CYP2D1 and CYP2D2 on their microsomal contents and enzymatic functions were examined. The substitution of Val-45 of CYP2D1 by glycine decreased the microsomal content, whereas the substitution of Gly-45 of CYP2D2 by valine increased. ...
Panoutsopoulos Georgios I - - 2004
BACKGROUND: 2-Phenylethylamine is an endogenous amine, which acts as a neuromodulator of dopaminergic responses. Exogenous 2-phenylethylamine is found in certain foodstuffs and may cause toxic side-effects in susceptible individuals. MATERIALS AND METHODS: The present investigation examined the metabolism of 2-phenylethylamine to phenylacetic acid, via phenylacetaldehyde, in freshly prepared and cryopreserved ...
Mason James M - - 2004
IL-4-induced gene-1 (Il4i1 or Fig1) initially isolated as a gene of unknown function from mouse B lymphocytes, is limited in expression to primarily immune tissues and genetically maps to a region of susceptibility to autoimmune disease. The predicted Il4i1 protein (IL4I1) sequence is most similar to apoptosis-inducing protein and Apoxin ...
Popova I V - - 2004
Natural uncouplers of oxidative phosphorylation, long-chain non-esterified fatty acids, cause uncoupling in the alkalo- and halotolerant bacterium Bacillus pseudofirmus FTU. The uncoupling effect in the bacterial cells was manifested as decrease of membrane potential and increase of respiratory activity. The membrane potential decrease was detected only in bacterial cells exhausted ...
Chien Liang-Jung - - 2004
Expression of the gene (daao) encoding D-amino acid oxidase (DAAO) in Escherichia coli typically results in a marked decrease of cell viability, and it has generally been assumed that the consumption of intracellular D-alanine by DAAO is responsible for this effect. Vitreoscilla hemoglobin (VHb) gene (vgb) was coexpressed with Rhodosporidium ...
Eisenhofer Graeme - - 2004
This article provides an update about catecholamine metabolism, with emphasis on correcting common misconceptions relevant to catecholamine systems in health and disease. Importantly, most metabolism of catecholamines takes place within the same cells where the amines are synthesized. This mainly occurs secondary to leakage of catecholamines from vesicular stores into ...
Negishi Osamu - - 2004
Caffeoyl quinic acid (CQA) derivatives in ku-ding-cha, mate, coffee, and related plants were determined by HPLC. One ku-ding-cha contained a large amount of 3,5-dicaffeoylquinic acid (3,5-diCQA, 10.6% in dry weight) as well as 3-CQA (1.7%), 4-CQA (1.1%), 5-CQA (6.3%), 3,4-diCQA (1.8%), and 4,5-diCQA (4.3%). In this ku-ding-cha, the total caffeic ...
Unno Tomonori - - 2004
Xanthine oxidase (XOD) is a key enzyme playing a role in hyperuricemia, catalyzing the oxidation of hypoxanthine to xanthine and then to uric acid. This study aimed to identify the XOD inhibitors from the leaves of Lagerstroemia speciosa (L.) Pers. (Lythraceae), which was traditionally used as a folk medicine in ...
Stábeli Rodrigo G - - 2004
The isolation and biochemical/enzymatic characterization of an L-amino acid oxidase, Balt-LAAO-I, from Bothrops alternatus snake venom, is described. Balt-LAAO-I is an acidic glycoprotein, pI approximately 5.37, homodimeric, Mr approximately 123,000, whose N-terminal sequence is ADVRNPLE EFRETDYEVL. It displays a high specificity toward hydrophobic and basic amino acids, while deglycosylation does ...
Fitzpatrick Paul F - - 2004
The present understanding of the mechanisms by which flavoproteins oxidize amino acid or hydroxy acids to the respective imino or keto acids is reviewed. The observation that many of these enzymes catalyze the elimination of HBr or HCl from the appropriate beta-halogenated substrate was long considered evidence for a carbanion ...
Shinn Andrew P - - 2004
Gyrodactylus thymalli Zitnan, 1960 and G. salaris Malmberg, 1957 have an indistinguishable ribosomal internal transcribed spacer (ITS) DNA sequence, but exhibit surprisingly high levels of intra- and interspecific sequence variation of the mitochondrial cytochrome oxidase I (CO1) gene. To test whether different populations of these reportedly very similar species could ...
Stefan Raluca-Ioana - - 2004
Monocrystalline natural diamond, L-amino acid oxidase (L-AAOD), D-amino acid oxidase (D-AAOD), and paraffin oil were used for the design of the modified diamond paste. The technique used for the direct voltammetric assay was differential pulse voltammetry (DPV) with applied potential pulse amplitude of 25 mV vs. Ag/AgCl. Using the new ...
Zhang Hongmin - - 2004
A snake-venom protein named AHP-LAAO has been purified from Agkistrodon halys pallas venom using four-stage chromatography. AHP-LAAO is a novel member of the snake-venom L-amino-acid oxidase family. Its amino-acid sequence shows high homology to other members of this family. For L-leucine, the values of k(cat) and K(M) are 31.1 s(-1) ...
Masuoka Noriyoshi - - 2004
Anacardic acid, 6[8(Z), 11(Z), 14-pentadecatrienyl]salicylic acid, inhibits generation of superoxide radicals by xanthine oxidase. This inhibition does not follow a hyperbolic inhibition, depends on anacardic acid concentrations, but follows a sigmoidal inhibition. The inhibition was analyzed by using a Hill equation, and slope factor and EC(50) were 4.3+/-0.5 and 53.6+/-5.1 ...
Erikson Oskar - - 2004
Selectable markers enable transgenic plants or cells to be identified after transformation. They can be divided into positive and negative markers conferring a selective advantage or disadvantage, respectively. We present a marker gene, dao1, encoding D-amino acid oxidase (DAAO, EC 1.4.3.3) that can be used for either positive or negative ...
Zhang Xiaochun - - 2004
Alcoholic cardiomyopathy is characterized by cardiomegaly, disruptions of myofibrillary architecture, reduced myocardial contractility, decreased ejection fraction, and enhanced risk of stroke and hypertension. Although several mechanisms have been postulated for alcoholic cardiomyopathy, including oxidative damage, accumulation of triglycerides, altered fatty acid extraction, decreased myofilament Ca(2+) sensitivity, and impaired protein synthesis, ...
Bakke Mikio - - 2004
Chemical modification was evaluated to stabilize pig kidney D-amino acid oxidase (pkDAAO), which is required for analytical determination of D-amino acids. Optimization of modification conditions was performed to obtain high recovery yield and stability, and chemical modification at 30 degrees C for 12 h with a highly concentrated enzyme solution ...
Campanella L - - 2004
Research was carried out to experimentally evaluate the antioxidant capacity of several red and white wines using a superoxide dismutase (SOD) biosensor recently developed by the present authors. Measurements were performed by comparing the biosensor response to increasing concentration of the superoxide radical produced in solution by the xanthine/xanthine oxidase ...
Le Bourvellec Carine - - 2004
The rate of consumption of dissolved oxygen by apple polyphenol oxidase in cider apple juices did not correlate with polyphenol oxidase activity in the fruits and decreased faster than could be explained by the decrease of its polyphenolic substrates. The kinetics parameters of a crude polyphenol oxidase extract, prepared from ...
Yoshida Nobuyuki - - 2004
Two putative fructosyl-amino acid oxidase genes, FAP1 and FAP2, found in the Schizosaccharomyces pombe genome were cloned and expressed. Both of the gene products (Fap1 and Fap2) were flavoproteins and have no activity for fructosyl-amino acids. It was suggested that Fap1 and Fap2 are an L-pipecolic acid oxidase and L-saccharopine ...
Tudella Valéria G - - 2004
Aspergillus fumigatus is an unusual pathogen in immunocompetent individuals; its incidence has increased in the last decades in patients immunocompromised, like those with chronic granulomatosis disease and AIDS. The aim of this study was to identify differences between the respiratory chain of host and the fungus planning to use the ...
Kim Mee-Hae - - 2004
Coupling both the electrocatalytic recycling of NADH and the enzymatic reduction of the substrate was used to produce (R)-mandelate from benzoylformate using benzoylformate reductase (BFR). The reduction of benzoylformate by BFR in combination with FAD-mediated electrolysis (at -0.5 V vs. Ag/AgCl) was complete in about 18 h and gave 47.5 ...
Inaba Yohei - - 2003
A D-alanine (D-Ala) sensor for the monitoring of a fermentation process was developed using flow injection analysis (FIA). The FIA system consisted of a D-amino acid oxidase (D-AAOx) reactor, a Pyruvate oxidase (PyOx) electrode and a contrast electrode in the flow cell, and through the oxidation of D-amino acids in ...
Stefan Raluca-Ioana - - 2003
A sequential injection analysis (SIA) is proposed for the simultaneous determination of L- and D-methotrexate (Mtx) using amperometric biosensors as detectors. A SIA system is proposed due to the highest precision and accuracy and lower consumption of sample and buffer. The amperometric biosensors used as detectors in SIA system were ...
Arfi Kenza - - 2003
Two Brevibacterium linens strains and the cheese-ripening yeast Geotrichum candidum were compared with regard to their ability to produce volatile sulfur compounds (VSCs) from three different precursors namely L-methionine, 4-methylthio-2-oxobutyric acid (KMBA) and 4-methylthio-2-hydroxybutyric acid (HMBA). All microorganisms were able to convert these precursors to VSCs. However, although all were ...
Ali Vahab - - 2003
Putative NADPH-dependent GDH (L-glycerate dehydrogenase) of the protozoan parasite Entamoeba histolytica (EhGDH) has been characterized. The EhGDH gene encodes a protein of 318 amino acids with a calculated isoelectric point of 6.29 and a molecular mass of 35.8 kDa. EhGDH showed highest identities with GDH from epsilon-proteobacteria. This close kinship ...
Petritis Konstantinos - - 2003
Varying concentrations of cyclopropane-1,1-dicarboxylic acid (CDA), an inhibitor of 1-aminocyclopropane-1-carboxylic acid oxidase, added to the solid culture medium of tomato nodal shoot segments resulted in a reduction in the level of endogenous ethylene according to the concentration of inhibitor applied. Following treatment with inhibitor, plants were homogenised and the concentrations ...
Baruah Ananta Madhab - - 2003
Changes in the specific activities of polyphenol oxidase (PPO), peroxidase (POD), and protease and in the relative amounts of flavan-3-ols for eight genetically derived cultivated teas at various stages of leaf maturity and in four succescive seasons were examined. A series of investigations were carried out to study the cross-reactivity ...
Wang Li-Zhen - - 2003
AIM: To elucidate the spatiotemporal relationships among D-serine, serine racemase, and D-amino acid oxidase (EC 1.4.3.3; DAO) in mouse cortex, striatum, cerebellum, heart, lung, liver, spleen, kidney, and skeletal muscle during mouse postnatal development. METHODS: The transcription levels of serine racemase and DAO were assayed by reverse transcription-polymerase chain reaction ...
Zhang Yu-Jie - - 2003
A novel L-amino acid oxidase, named TSV-LAO, has been purified and cloned from the snake Trimeresurus stejnegeri. Fifty percentage cytotoxic concentrations (CC50) of TSV-LAO on C8166 cells were 24 and 390 nM in the absence or presence of catalase (400 nM), respectively. However, at concentrations that showed little effect on ...
Shi Guoyue - - 2003
An effective microseparation system integrated with ring-disc electrodes and two microfluidic devices was fabricated for in vivo determination using a microdialysis pump. The major interference of ascorbic acid (AA) was excluded by direct oxidation with ascorbate oxidase. Glucose, glutamate, and choline were successfully determined simultaneously through the biosensors modified with ...
Molla Gianluca - - 2003
Rhodotorula gracilis is a oleaginous yeast which utilizes D-amino acids as a source of carbon and/or nitrogen. D-amino acid oxidase (DAAO), which converts D-amino acids in the corresponding alpha-keto acids and ammonia, is the first enzyme involved in the catabolism of D-amino acids. DAAO activity is induced by the presence ...
Inaba Yohei - - 2003
The concentrations of D- and L-alanine in bivalves are useful as indicators of environmental pollution. Amino acid oxidase with a low substrate specificity catalyzes the oxidation of various amino acids. Among the various amino acids, pyruvic acid can be generated from alanine only by the catalytic oxidative reaction of this ...
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