An enzyme that converts ascorbic acid to dehydroascorbic acid. EC 1.10.3.3.
A copper-containing oxidoreductase enzyme that catalyzes the oxidation of 4-benzenediol to 4-benzosemiquinone. It also has activity towards a variety of O-quinols and P-quinols. It primarily found in FUNGI and is involved in LIGNIN degradation, pigment biosynthesis and detoxification of lignin-derived products.
A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.
A genus (formerly part of Rhus genus) of shrubs, vines, or trees that yields a highly allergenic oleoresin which causes a severe contact dermatitis (DERMATITIS, TOXICODENDRON). The most toxic species are Toxicodendron vernix (poison sumac), T. diversilobum (poison oak), and T. radicans (poison ivy). T. vernicifera yields a useful varnish from which certain enzymes (laccases) are obtained.
Use of a pulse of X-rays or fast electrons to generate free radicals for spectroscopic examination.
A mitosporic fungal genus with many reported ascomycetous teleomorphs. Cephalosporin antibiotics are derived from this genus.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.
A creeping annual plant species of the CUCURBITACEAE family. It has a rough succulent, trailing stem and hairy leaves with three to five pointed lobes.
Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.
Peroxidases that utilize ASCORBIC ACID as an electron donor to reduce HYDROGEN PEROXIDE to WATER. The reaction results in the production of monodehydroascorbic acid and DEHYDROASCORBIC ACID.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
A flavoprotein enzyme that catalyzes the univalent reduction of OXYGEN using NADPH as an electron donor to create SUPEROXIDE ANION. The enzyme is dependent on a variety of CYTOCHROMES. Defects in the production of superoxide ions by enzymes such as NADPH oxidase result in GRANULOMATOUS DISEASE, CHRONIC.
Ceruloplasmin is a blue copper-containing protein primarily synthesized in the liver, functioning as a ferroxidase enzyme involved in iron homeostasis and contributing to copper transportation in the body.
A bacterial protein from Pseudomonas, Bordetella, or Alcaligenes which operates as an electron transfer unit associated with the cytochrome chain. The protein has a molecular weight of approximately 16,000, contains a single copper atom, is intensively blue, and has a fluorescence emission band centered at 308nm.

Azide binding to the trinuclear copper center in laccase and ascorbate oxidase. (1/79)

Azide binding to the blue copper oxidases laccase and ascorbate oxidase (AO) was investigated by electron paramagnetic resonance (EPR) and pulsed electron-nuclear double resonance (ENDOR) spectroscopies. As the laccase : azide molar ratio decreases from 1:1 to 1:7, the intensity of the type 2 (T2) Cu(II) EPR signal decreases and a signal at g approximately 1.9 appears. Temperature and microwave power dependent EPR measurements showed that this signal has a relatively short relaxation time and is therefore observed only below 40 K. A g approximately 1.97 signal, with similar saturation characteristics was found in the AO : azide (1:7) sample. The g < 2 signals in both proteins are assigned to an S = 1 dipolar coupled Cu(II) pair whereby the azide binding disrupts the anti-ferromagnetic coupling of the type 3 (T3) Cu(II) pair. Analysis of the position of the g < 2 signals suggests that the distance between the dipolar coupled Cu(II) pair is shorter in laccase than in AO. The proximity of T2 Cu(II) to the S = 1 Cu(II) pair enhances its relaxation rate, reducing its signal intensity relative to that of native protein. The disruption of the T3 anti-ferromagnetic coupling occurs only in part of the protein molecules, and in the remaining part a different azide binding mode is observed. The 130 K EPR spectra of AO and laccase with azide (1:7) exhibit, in addition to an unperturbed T2 Cu(II) signal, new features in the g parallel region that are attributed to a perturbed T2 in protein molecules where the anti-ferromagnetic coupling of T3 has not been disrupted. While these features are also apparent in the AO : azide sample at 10 K, they are absent in the EPR spectra of the laccase : azide sample measured in the range of 6-90 K. Moreover, pulsed ENDOR measurements carried out at 4.2 K on the latter exhibited only a reduction in the intensity of the 20 MHz peak of the 14N histidine coordinated to the T2 Cu(II) but did not resolve any significant changes that could indicate azide binding to this ion. The lack of T2 Cu(II) signal perturbation below 90 K in laccase may be due to temperature dependence of the coupling within the trinuclear : azide complex.  (+info)

Homology modeling of the multicopper oxidase Fet3 gives new insights in the mechanism of iron transport in yeast. (2/79)

Fet3, the multicopper oxidase of yeast, oxidizes extracellular ferrous iron which is then transported into the cell through the permease Ftr1. A three-dimensional model structure of Fet3 has been derived by homology modeling. Fet3 consists of three cupredoxin domains joined by a trinuclear copper cluster which is connected to the blue copper site located in the third domain. Close to this site, which is the primary electron acceptor from the substrate, residues for a potential iron binding site could be identified. The surface disposition of negatively charged residues suggests that Fet3 can translocate Fe(3+) to the permease Ftr1 through a pathway under electrostatic guidance.  (+info)

Effects of superoxide anion generators and thiol modulators on nitrergic transmission and relaxation to exogenous nitric oxide in the sheep urethra. (3/79)

The effects of superoxide anion generators, the nitric oxide (NO) scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoine-1-oxyl 3-oxide (carboxy-PTIO), the specific guanylate cyclase inhibitor 1H-[1,2,4]-oxadiazole-[4,3-a]-quinoxalin-1-one (ODQ), and thiol modulating agents were investigated on relaxations induced by nitrergic stimulation and exogenous NO addition in the sheep urethra. Methylene blue (MB, 10 microM), pyrogallol (0.1 mM) and xanthine (X, 0.1 mM)/xanthine oxidase (XO, 0.1 u ml(-1)) inhibited NO-mediated relaxations, without affecting those induced by nitrergic stimulation. This resistance was not diminished following inhibition of endogenous Cu/Zn superoxide dismutase (Cu/Zn SOD) with diethyldithiocarbamic acid (DETCA, 3 mM), which almost abolished tissue SOD activity. Carboxy-PTIO (0.1 - 0.5 mM) inhibited NO-mediated relaxations but had no effect on responses to nitrergic stimulation, which were not changed by treatment with ascorbate oxidase (2 u ml(-1)). Relaxations to NO were reduced, but not abolished, by ODQ (10 microM), while nitrergic responses were completely blocked. The thiol modulators, ethacrynic acid (0.1 mM), diamide (1.5 mM), or 5,5'-dithio-bis (2-nitrobenzoic acid) (DTNB, 0. 5 mM), and subsequent treatment with dithiothreitol (DTT, 2 mM) had no effect on responses to nitrergic stimulation or NO. In contrast, N-ethylmaleimide (NEM, 0.2 mM) markedly inhibited both relaxations. L-cysteine (L-cys, 0.1 mM) had no effect on responses to NO, while it inhibited those to nitrergic stimulation, in a Cu/Zn SOD-independent manner. Our results do not support the view that the urethral nitrergic transmitter is free NO, and the possibility that another compound is acting as mediator still remains open. British Journal of Pharmacology (2000) 129, 53 - 62  (+info)

Auxin metabolism in the root apical meristem. (4/79)

Within the root meristem of flowering plants is a group of mitotically inactive cells designated the quiescent center (QC). Recent work links the quiescent state to high levels of the growth regulator auxin that accumulates in the QC via polar transport. This in turn results in elevated levels of the enzyme ascorbic acid oxidase (AAO), resulting in a reduction of ascorbic acid (AA) within the QC and mitotic quiescence. We present evidence for additional interactions between auxin, AAO, and AA, and report that, in vitro, AAO oxidatively decarboxylates auxin, suggesting a mechanism for regulating auxin levels within the QC. We also report that oxidative decarboxylation occurs at the root tip and that an intact root cap must be present for this metabolic event to occur. Finally, we consider how interaction between auxin and AAO may influence root development by regulating the formation of the QC.  (+info)

Erythrocytes reduce extracellular ascorbate free radicals using intracellular ascorbate as an electron donor. (5/79)

Ascorbate is readily oxidized in aqueous solution by ascorbate oxidase. Ascorbate radicals are formed, which disproportionate to ascorbate and dehydroascorbic acid. Addition of erythrocytes with increasing intracellular ascorbate concentrations decreased the oxidation of ascorbate in a concentration-dependent manner. Concurrently, it was found, utilizing electron spin resonance spectroscopy, that extracellular ascorbate radical levels were decreased. Control experiments showed that these results could not be explained by leakage of ascorbate from the cells, inactivation of ascorbate oxidase, or oxygen depletion. Thus, this means that intracellular ascorbate is directly responsible for the decreased oxidation of extracellular ascorbate. Exposure of ascorbate-loaded erythrocytes to higher levels of extracellular ascorbate radicals resulted in the detection of intracellular ascorbate radicals. Moreover, efflux of dehydroascorbic acid was observed under these conditions. These data confirm the view that intracellular ascorbate donates electrons to extracellular ascorbate free radical via a plasma membrane redox system. Such a redox system enables the cells to effectively counteract oxidative processes and thereby prevent depletion of extracellular ascorbate.  (+info)

Analysis of expressed sequence tags of flower buds in Lotus japonicus. (6/79)

In order to study gene expression in a reproductive organ, we constructed a cDNA library of mature flower buds in Lotus japonicus, and characterized expressed sequence tags (ESTs) of 842 clones randomly selected. The EST sequences were clustered into 718 non-redundant groups. From BLAST and FASTA search analyses of both protein and DNA databases, 58.5% of the EST groups showed significant sequence similarities to known genes. Several genes encoding these EST clones were identified as pollen-specific genes, such as pectin methylesterase, ascorbate oxidase, and polygalacturonase, and as homologous genes involved in pollen-pistil interaction. Comparison of these EST sequences with those derived from the whole plant of L. japonicus, revealed that 64.8% of EST sequences from the flower buds were not found in EST sequences of the whole plant. Taken together, the EST data from flower buds generated in this study is useful in dissecting gene expression in floral organ of L. japonicus.  (+info)

Behavioral activation in rats requires endogenous ascorbate release in striatum. (7/79)

Ascorbate (vitamin C) is found in high concentrations in the striatum in which it may play a role in behavioral activation. To test this hypothesis, freely behaving rats received bilateral intrastriatal infusions of ascorbate oxidase (AAO) to inactivate extracellular ascorbate. Slow-scan voltammetry was used simultaneously to assess changes in ascorbate and 3,4-dihydroxyphenylacetic acid (DOPAC), a major dopamine metabolite, near the infusion site. Intrastriatal AAO, but not saline vehicle, caused a rapid decline in both ascorbate and behavioral activation. Within 20 min, an ascorbate loss of 50-70% led to a near-total inhibition of all recorded behavior, including open-field locomotion, approach of novel objects, and social interactions with other rats. DOPAC levels remained stable, arguing against an AAO-induced disruption of dopamine transmission. Consistent with this interpretation, subsequent injection of 1.0 mg/kg d-amphetamine, an indirect dopamine agonist, quickly restored behavioral activation, which also was accompanied by a marked rise in extracellular ascorbate. Bilateral AAO infusions into dorsal hippocampus, which also has a high level of extracellular ascorbate, failed to alter behavioral activation, indicating that a loss of brain ascorbate per se does not suppress behavior. Collectively, these results implicate ascorbate in the behavioral operations of the striatum and suggest that the extracellular level of this vitamin plays a critical role in behavioral activation.  (+info)

Molecular and biochemical characterization of a highly stable bacterial laccase that occurs as a structural component of the Bacillus subtilis endospore coat. (8/79)

The Bacillus subtilis endospore coat protein CotA shows laccase activity. By using comparative modeling techniques, we were able to derive a model for CotA based on the known x-ray structures of zucchini ascorbate oxidase and Cuprinus cereneus laccase. This model of CotA contains all the structural features of a laccase, including the reactive surface-exposed copper center (T1) and two buried copper centers (T2 and T3). Single amino acid substitutions in the CotA T1 copper center (H497A, or M502L) did not prevent assembly of the mutant proteins into the coat and did not alter the pattern of extractable coat polypeptides. However, in contrast to a wild type strain, both mutants produced unpigmented colonies and spores unable to oxidize syringaldazine (SGZ) and 2'2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The CotA protein was purified to homogeneity from an overproducing Escherichia coli strain. The purified CotA shows an absorbance and a EPR spectra typical of blue multicopper oxidases. Optimal enzymatic activity was found at < or =pH 3.0 and at pH 7.0 for ABTS or SGZ oxidation, respectively. The apparent K(m) values for ABTS and SGZ at 37 degrees C were of 106 +/- 11 and 26 +/- 2 microm, respectively, with corresponding k(cat) values of 16.8 +/- 0.8 and 3.7 +/- 0.1 s(-1). Maximal enzyme activity was observed at 75 degrees C with ABTS as substrate. Remarkably, the coat-associated or the purified enzyme showed a half-life of inactivation at 80 degrees C of about 4 and 2 h, respectively, indicating that CotA is intrinsically highly thermostable.  (+info)

Ascorbate oxidase is an enzyme that catalyzes the oxidation of ascorbic acid (vitamin C) to dehydroascorbic acid in the presence of oxygen. This reaction also results in the production of water and hydrogen peroxide as byproducts. Ascorbate oxidase plays a significant role in regulating the levels of ascorbic acid in plants, where it is primarily found. It belongs to the family of copper-containing oxidoreductases. The enzyme's active site contains two copper ions that facilitate the electron transfer during the catalytic process. Ascorbate oxidase is not considered essential for human health since humans do not produce ascorbic acid and must obtain it through dietary sources.

Laccase is an enzyme (specifically, a type of oxidoreductase) that is widely distributed in plants, fungi, and bacteria. It catalyzes the oxidation of various phenolic compounds, including polyphenols, methoxy-substituted phenols, aromatic amines, and some inorganic ions, while reducing molecular oxygen to water. This enzyme plays a crucial role in lignin degradation, as well as in the detoxification of xenobiotic compounds and in the synthesis of various pigments and polymers. The medical relevance of laccase is linked to its potential applications in bioremediation, biofuel production, and biotechnology.

Ascorbic acid is the chemical name for Vitamin C. It is a water-soluble vitamin that is essential for human health. Ascorbic acid is required for the synthesis of collagen, a protein that plays a role in the structure of bones, tendons, ligaments, and blood vessels. It also functions as an antioxidant, helping to protect cells from damage caused by free radicals.

Ascorbic acid cannot be produced by the human body and must be obtained through diet or supplementation. Good food sources of vitamin C include citrus fruits, strawberries, bell peppers, broccoli, and spinach.

In the medical field, ascorbic acid is used to treat or prevent vitamin C deficiency and related conditions, such as scurvy. It may also be used in the treatment of various other health conditions, including common cold, cancer, and cardiovascular disease, although its effectiveness for these uses is still a matter of scientific debate.

"Toxicodendron" is a genus of flowering plants in the family Anacardiaceae, also known as the cashew family. This genus includes several species that are well-known for causing allergic reactions in humans, particularly through contact with their sap or urushiol-containing parts of the plant. The most common and notorious species in this genus is Toxicodendron radicans, also known as poison ivy, poison oak, and poison sumac. These plants can cause an itchy, blistering rash upon contact with the skin, which is a type of allergic reaction called contact dermatitis. The severity of the reaction can vary from person to person, depending on their sensitivity to urushiol and the amount of exposure they have had to the plant.

Pulse radiolysis is not a medical term, but rather a technique used in physical chemistry and radiation biology. It involves the use of short, intense pulses of ionizing radiation to induce chemical reactions in matter, which are then studied using fast spectroscopic techniques to observe the formation and decay of transient species.

In the context of medical research, pulse radiolysis can be used to study the mechanisms of radiation damage to biological molecules such as DNA, proteins, and lipids, which is relevant for understanding the biological effects of ionizing radiation in cancer therapy and radiation protection.

"Acremonium" is a genus of filamentous fungi that are commonly found in soil, decaying vegetation, and water. Some species of Acremonium can cause infections in humans, particularly in individuals with weakened immune systems. These infections can affect various organs and tissues, including the skin, nails, lungs, and eyes.

The medical definition of "Acremonium" is therefore a type of fungus that can cause a variety of infectious diseases, particularly in immunocompromised individuals. It's important to note that Acremonium infections are relatively rare, but they can be serious and require prompt medical treatment.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

Copper is a chemical element with the symbol Cu (from Latin: *cuprum*) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. Copper is found as a free element in nature, and it is also a constituent of many minerals such as chalcopyrite and bornite.

In the human body, copper is an essential trace element that plays a role in various physiological processes, including iron metabolism, energy production, antioxidant defense, and connective tissue synthesis. Copper is found in a variety of foods, such as shellfish, nuts, seeds, whole grains, and organ meats. The recommended daily intake of copper for adults is 900 micrograms (mcg) per day.

Copper deficiency can lead to anemia, neutropenia, impaired immune function, and abnormal bone development. Copper toxicity, on the other hand, can cause nausea, vomiting, abdominal pain, diarrhea, and in severe cases, liver damage and neurological symptoms. Therefore, it is important to maintain a balanced copper intake through diet and supplements if necessary.

'Cucumis sativus' is the scientific name for the vegetable we commonly know as a cucumber. It belongs to the family Cucurbitaceae and is believed to have originated in South Asia. Cucumbers are widely consumed raw in salads, pickled, or used in various culinary applications. They have a high water content and contain various nutrients such as vitamin K, vitamin C, and potassium.

I apologize for any confusion, but "plants" is not a term that has a medical definition. The term "plants" refers to a large and diverse group of organisms that obtain their energy through photosynthesis, which is the process of converting sunlight into chemical energy. Plants are typically characterized by having cells with cell walls containing cellulose, chloroplasts containing the pigment chlorophyll, and the ability to synthesize their own food through photosynthesis.

In a medical or biological context, you might be thinking of "plant-based" or "phytomedicine," which refer to the use of plants or plant extracts as a form of medicine or treatment. Phytomedicines have been used for thousands of years in many traditional systems of medicine, and some plant-derived compounds have been found to have therapeutic benefits in modern medicine as well. However, "plants" itself does not have a medical definition.

Ascorbate peroxidases (AHPX) are a group of enzymes that use ascorbic acid (vitamin C) as a reducing cofactor to catalyze the conversion of hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). This reaction helps protect cells from oxidative damage caused by the accumulation of H2O2, a byproduct of various metabolic processes. Ascorbate peroxidases are primarily found in plants, algae, and cyanobacteria, where they play a crucial role in the detoxification of reactive oxygen species generated during photosynthesis.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

NADPH oxidase is an enzyme complex that plays a crucial role in the production of reactive oxygen species (ROS) in various cell types. The primary function of NADPH oxidase is to catalyze the transfer of electrons from NADPH to molecular oxygen, resulting in the formation of superoxide radicals. This enzyme complex consists of several subunits, including two membrane-bound components (gp91phox and p22phox) and several cytosolic components (p47phox, p67phox, p40phox, and rac1 or rac2). Upon activation, these subunits assemble to form a functional enzyme complex that generates ROS, which serve as important signaling molecules in various cellular processes. However, excessive or uncontrolled production of ROS by NADPH oxidase has been implicated in the pathogenesis of several diseases, such as cardiovascular disorders, neurodegenerative diseases, and cancer.

Ceruloplasmin is a protein found in blood plasma that binds and transports copper ions. It plays a crucial role in copper metabolism, including the oxidation of ferrous iron to ferric iron, which is necessary for the incorporation of iron into transferrin, another protein responsible for transporting iron throughout the body. Ceruloplasmin also acts as an antioxidant by scavenging free radicals and has been implicated in neurodegenerative disorders like Alzheimer's disease and Wilson's disease, a genetic disorder characterized by abnormal copper accumulation in various organs.

Azurin is a small protein with a blue copper center, which is involved in electron transfer reactions. It is produced by the bacterium *Pseudomonas aeruginosa*, and has been studied for its potential role in wound healing and as an anticancer agent. The name "azurin" comes from the fact that this protein has a bright blue color due to its copper ion content.

... ascorbate oxidase, ascorbic oxidase, ascorbate dehydrogenase, L-ascorbic acid oxidase, AAO, L-ascorbate:O2 oxidoreductase, and ... In enzymology, a L-ascorbate oxidase (EC 1.10.3.3) is an enzyme that catalyzes the chemical reaction 2 L-ascorbate + O2 ⇌ {\ ... Mondovì B, Avigliano L (February 1984). "Ascorbate oxidase.". In Lontie R (ed.). Copper Proteins and Copper Enzymes. Boca Raton ... This enzyme participates in ascorbate metabolism. It employs one cofactor, copper. The systematic name of this enzyme class is ...
Bleeg HS, Christensen F (1982). "Biosynthesis of ascorbate in yeast. Purification of L-galactono-1,4-lactone oxidase with ... In enzymology, a L-galactonolactone oxidase (EC 1.3.3.12) is an enzyme that catalyzes the chemical reaction L-galactono-1,4- ... This enzyme is also called L-galactono-1,4-lactone oxidase. This enzyme participates in ascorbic acid and aldaric acid ... lactone + O2 ⇌ {\displaystyle \rightleftharpoons } L-ascorbate + H2O2 Thus, the two substrates of this enzyme are L-galactono-1 ...
Messerschmidt A, Huber R (January 1990). "The blue oxidases, ascorbate oxidase, laccase and ceruloplasmin. Modelling and ... Ascorbate oxidase EC 1.10.3.3, a 3-domain enzyme found in higher plants. Nitrite reductase EC 1.7.2.1, a 2-domain enzyme ... Multicopper oxidases include: Ceruloplasmin EC 1.16.3.1 (ferroxidase), a 6-domain enzyme found in the serum of mammals and ... In addition to the above enzymes there are a number of other proteins that are similar to the multi-copper oxidases in terms of ...
White GA, Krupka RM (1965). "Ascorbic acid oxidase and ascorbic acid oxygenase of Myrothecium verrucaria". Arch. Biochem. ... Ascorbate 2,3-dioxygenase (EC 1.13.11.13) is an enzyme that catalyzes the chemical reaction ascorbate + O2 + H2O ⇌ {\ ... The systematic name of this enzyme class is ascorbate:oxygen 2,3-oxidoreductase (bond-cleaving). This enzyme is also called ... This enzyme participates in ascorbate and aldarate metabolism. It employs one cofactor, iron. ...
In its patently pathological form, the effects of ascorbate deficiency are manifested as scurvy. It is likely that some level ... GULO belongs to a family of sugar-1,4-lactone oxidases, which also contains the yeast enzyme D-arabinono-1,4-lactone oxidase ( ... L-Gulonolactone oxidase (EC 1.1.3.8) is an enzyme that produces vitamin C, but is non-functional in Haplorrhini (including ... L-Gulonolactone oxidase deficiency has been called "hypoascorbemia" and is described by OMIM (Online Mendelian Inheritance in ...
These species require external ascorbate supply, because they lack the biosynthetic enzyme L-gulonolactone oxidase. The ... Glucuronic acid is a precursor of ascorbic acid (vitamin C, formerly called L-hexuronic acid). Ascorbate can be biosynthesized ...
Cytochrome c peroxidase is used as a soluble, easily purified model for cytochrome c oxidase. Ascorbate peroxidase Chloride ...
... and bacterial ascorbate oxidase, among others. While hephaestin shares 50% amino acid sequence identity with its serum ... a multicopper oxidase with ferroxidase activity". Biochemistry. 44 (45): 14725-31. doi:10.1021/bi051559k. hdl:2429/18540. PMID ... 610 nm consistent with other blue multicopper oxidases such as ceruloplasmin. By using ferrous ammonium sulfate as a substrate ... Hephaestin is a member of the family of copper oxidases that includes mammalian ceruloplasmin, yeast fet3 and fet5, ...
... which is a signal to downregulate its own expression of ascorbate oxidase and ascorbate peroxidase. AO and AP are reactive ...
The oxygen incorporated need not be derived from O2 with reduced ascorbate as one donor, and incorporation of one atom of ... In enzymology, an aminocyclopropanecarboxylate oxidase (EC 1.14.17.4) is an enzyme that catalyzes the chemical reaction 1- ... ascorbate, and O2, whereas its 5 products are ethylene, cyanide, dehydroascorbate, CO2, and H2O. This enzyme belongs to the ... Other names in common use include ACC oxidase, and ethylene-forming enzyme. As of late 2007, two structures have been solved ...
Ascorbate salts such as sodium ascorbate and calcium ascorbate are used in some dietary supplements. These release ascorbate ... Nishikimi M, Kawai T, Yagi K (October 1992). "Guinea pigs possess a highly mutated gene for L-gulono-gamma-lactone oxidase, the ... However, taking vitamin C in the form of sodium ascorbate and calcium ascorbate may minimize this effect. Other symptoms ... In plants, vitamin C is a substrate for ascorbate peroxidase. This enzyme utilizes ascorbate to neutralize excess hydrogen ...
4-dihydroxyphenethylamine beta-oxidase 4-(2-aminoethyl) pyrocatechol beta-oxidase dopa beta-hydroxylase dopamine beta-oxidase ... DBH is a 290 kDa copper-containing oxygenase consisting of four identical subunits, and its activity requires ascorbate as a ... The three substrates of the enzyme are dopamine, vitamin C (ascorbate), and O2. The products are norepinephrine, ... The systematic name of this enzyme class is 3,4-dihydroxyphenethylamine, ascorbate:oxygen oxidoreductase (beta-hydroxylating). ...
D-erythro-ascorbate + H2O2 Thus, the two substrates of this enzyme are D-arabinono-1,4-lactone and O2, whereas its two products ... In enzymology, a D-arabinono-1,4-lactone oxidase (EC 1.1.3.37) is an enzyme that catalyzes the chemical reaction D-arabinono-1, ... Huh WK, Kim ST, Yang KS, Seok YJ, Hah YC, Kang SO (1994). "Characterisation of D-arabinono-1,4-lactone oxidase from Candida ... are D-erythro-ascorbate and H2O2. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH ...
... including that of ascorbate oxidase, and of other metallo-enzymes. These studies have thrown new light on electron-transfer ...
Pauling argued that because humans lack a functional form of L-gulonolactone oxidase, an enzyme required to make vitamin C that ... Rath M, Pauling L (1990). "Hypothesis: lipoprotein(a) is a surrogate for ascorbate". Proc. Natl. Acad. Sci. USA. 87 (16): 6204- ... Jenness R, Birney E, Ayaz K (1980). "Variation of l-gulonolactone oxidase activity in placental mammals". Comparative ... Cameron E, Pauling L (October 1976). "Supplemental ascorbate in the supportive treatment of cancer: Prolongation of survival ...
An example of a pseudogene is the gene for L-gulonolactone oxidase, a liver enzyme necessary for biosynthesis of L-ascorbic ... including humans which require ascorbic acid or ascorbate from food. The remains of this non-functional gene with many ... Nishikimi M, Kawai T, Yagi K (October 1992). "Guinea pigs possess a highly mutated gene for L-gulono-gamma-lactone oxidase, the ...
Animals that can contract scurvy all lack the L-gulonolactone oxidase (GULO) enzyme, which is required in the last step of ... All species that do not synthesize ascorbate require it in the diet. Deficiency causes scurvy in humans, and somewhat similar ... Nishikimi M, Kawai T, Yagi K (October 1992). "Guinea pigs possess a highly mutated gene for L-gulono-gamma-lactone oxidase, the ... the lack of working L-gulonolactone oxidase (GULO) enzyme has no significance, and in modern Western societies, scurvy is ...
Amazingly, oxalate is a metabolite of ascorbate (vitamin C), and it is worth emphasizing that ascorbate is a direct precursor ... Many years later it was found to have oxalate oxidase activity generating 'antimicrobial' hydrogen peroxide from a substrate of ... oxalate oxidase 'one-very-tough-little- protein' was such an ancestor. This hypothesis stimulated a search for the evolutionary ... it was found to be an enzyme having oxalate oxidase (OXO) activity converting an oxalate substrate into carbon dioxide and ...
... ubiquinol oxidase (H+-transporting) * EC 7.1.1.4: caldariellaquinol oxidase (H+-transporting) * EC 7.1.1.5: menaquinol oxidase ... ascorbate ferrireductase (transmembrane) * * No Wikipedia article EC 7.2.2.1: Na+-transporting two-sector ATPase * EC 7.2.2.2: ... cytochrome-c oxidase * EC 7.1.1.10: ferredoxin-quinone oxidoreductase (H+-translocating) * EC 7.1.1.11: ferredoxin-NAD+ ... H+-transporting) * EC 7.1.1.6: plastoquinol-plastocyanin reductase * EC 7.1.1.7: quinol oxidase (electrogenic, proton-motive ...
Citric and ascorbic acids target enzymes that degrade fruits and vegetables, e.g., mono/polyphenol oxidase which turns surfaces ... The most common antioxidant additives are ascorbic acid (vitamin C) and ascorbates. Thus, antioxidants are commonly added to ...
Xanthine oxidase is a large enzyme whose active site consists of the metal molybdenum bound to sulfur and oxygen. Uric acid is ... Proctor, P. (November 1970). "Similar functions of uric acid and ascorbate in man?". Nature. 228 (5274): 868. Bibcode:1970Natur ... The enzyme xanthine oxidase (XO) catalyzes the formation of uric acid from xanthine and hypoxanthine. XO, which is found in ... Pacher, P.; Nivorozhkin, A.; Szabó, C. (2006). "Therapeutic effects of xanthine oxidase inhibitors: Renaissance half a century ...
Ether lipid oxidase (alkylglycerol monooxygenase, AGMO) catalyses the conversion of 1-alkyl-sn-glycerol to 1-hydroxyalkyl-sn- ... Research shows that ascorbic acid (also known as ascorbate or vitamin C) can reduce BH3 radical into BH4, preventing the BH3 ...
... ascorbate 2,3-dioxygenase - assembled epitope - ataxia-telangiectasia - ATG or AUG - autoimmune lymphoproliferative syndrome - ... 4-hydroxyphenylpyruvate oxidase - 4-Nitrophenol 4-monooxygenase - 4933425L06Rik - 5' end - 5' flanking region - 5-pyridoxate ... menaquinol oxidase (H+-transporting) - Johann Mendel - Mendelian inheritance - message - messenger RNA - metaphase - ...
NADPH Oxidase Family 5.B.2 The Eukaryotic Cytochrome b561 (Cytb561) Family 5.B.3 The Geobacter Nanowire Electron Transfer (G- ... Family 4.A.7 The PTS L-Ascorbate (L-Asc) Family 4.B.1 The Nicotinamide Ribonucleoside (NR) Uptake Permease (PnuC) Family 4.C.1 ... Superfamily 3.D.4 Proton-translocating Cytochrome Oxidase (COX) Superfamily 3.D.5 The Na+-translocating NADH:Quinone ...
Ferrous-oxidase mediated transport systems exist in order to transport specific ions opposed to DMT1, which does not have ... of iron being reduced by ferrireductases that are present on the cell surface or by dietary reductants such as ascorbate ( ... So in anaerobic environments the oxidase would not be able to function thus another means of iron uptake is necessary. Toxic ...
... and can effectively scavenge NO at oxygen levels far below the saturation of cytochrome c oxidase. In the course of the ... "Nitric oxide scavenging by barley hemoglobin is facilitated by a monodehydroascorbate reductase-mediated ascorbate reduction of ...
Peterkofsky, B (1991). "Ascorbate requirement for hydroxylation and secretion of procollagen: Relationship to inhibition of ... Formation of the collagen fibril: lysyl oxidase, an extracellular copper-dependent enzyme, produces the final step in the ... The reaction consumes one ascorbate molecule per hydroxylation. The synthesis of collagen occurs inside and outside of the cell ... Myllylä, R.; Majamaa, K.; Günzler, V.; Hanauske-Abel, H. M.; Kivirikko, K. I. (1984). "Ascorbate is consumed stoichiometrically ...
2 ferrocytochrome b5 EC 1.10.2.1 L-ascorbate-cytochrome-b5 reductase L-ascorbate + ferricytochrome b5 → monodehydroascorbate + ... sulfite oxidase (EC 1.8.3.1), plant and fungal nitrate reductases (EC 1.7.1.1, EC 1.7.1.2, EC 1.7.1.3), and plant and fungal ...
Electron donors may include ascorbate, cytochrome b5 or ferredoxin reductase. The catalytic NO dioxygenation can be written in ... and cytochrome oxidase, the last enzyme in the respiratory electron transport chain of mitochondria. Additionally NO, with its ...
Myllylä R, Majamaa K, Günzler V, Hanauske-Abel HM, Kivirikko KI (May 1984). "Ascorbate is consumed stoichiometrically in the ... "Crystal structure and mechanistic implications of 1-aminocyclopropane-1-carboxylic acid oxidase - the ethylene-forming enzyme ... The catalytic activity of many αKG-dependent dioxygenases are dependent on reducing agents (especially ascorbate) although the ... on ascorbate and other reducing agents" (PDF). Biochem. J. 427 (1): 135-142. doi:10.1042/BJ20091609. PMID 20055761. Welford RW ...
... ascorbate oxidase, ascorbic oxidase, ascorbate dehydrogenase, L-ascorbic acid oxidase, AAO, L-ascorbate:O2 oxidoreductase, and ... In enzymology, a L-ascorbate oxidase (EC 1.10.3.3) is an enzyme that catalyzes the chemical reaction 2 L-ascorbate + O2 ⇌ {\ ... Mondovì B, Avigliano L (February 1984). "Ascorbate oxidase.". In Lontie R (ed.). Copper Proteins and Copper Enzymes. Boca Raton ... This enzyme participates in ascorbate metabolism. It employs one cofactor, copper. The systematic name of this enzyme class is ...
APX, ascorbate peroxidase; CAT, catalase; CodA, choline oxidase; GABA, γ-aminobutyric acid; MtlD, mannitol-1-phosphate ... APX, ascorbate peroxidase; CAT, catalase; CodA, choline oxidase; GABA, γ-aminobutyric acid; MtlD, mannitol-1-phosphate ... Choline oxidase (codA). AY304485. Arthrobacter. globiformis. Diospyros kaki. Salt stress. [158]. Sorbitol-6-phosphate ... In response to SS, ornithine decarboxylase, diamine oxidase and S-adenosylmethionine decarboxylase activities increased in both ...
Apoplastic ascorbate oxidases (AOs) play a critical role in reactive oxygen species (ROS)-mediated innate host immunity by ... Apoplastic ascorbate oxidases (AOs) play a critical role in reactive oxygen species (ROS)-mediated innate host immunity by ... Co-evolved Plant And Blast Fungus Ascorbate Oxidases Orchestrate The Redox State Of Host Apoplast To Modulate Rice Immunity. ... "Co-evolved Plant And Blast Fungus Ascorbate Oxidases Orchestrate The Redox State Of Host Apoplast To Modulate Rice Immunity" ( ...
This draw on ascorbate, from whatever source, lowers the blood level of ascorbate to a negligible level. I have coined the term ... This defect is caused by a mutated defective gene for the liver enzyme, L-gulonolactone oxidase. The higher mammals (except for ... Humans loaded with ascorbate would appear to recover similarly to the animals which make their own ascorbate in response to ... Ascorbate should be used in cancer patients to avert disorders of ascorbate deficiency in various systems of the body including ...
PDB Description: refined crystal structure of ascorbate oxidase at 1.9 angstroms resolution ... d1aoza2 b.6.1.3 (A:130-338) Ascorbate oxidase {Zucchini (Cucurbita pepo medullosa)} ...
The sample is initially incubated with a reagent mixture containing ascorbate oxidase and a clearing system. In this test ... In the presence of oxygen, free cholesterol is oxidized by cholesterol oxidase to cholest-4-en-3-one. The H2O2 reacts in the ... sarcosine oxidase, kits # 1775677 and 1775766) performed on a Roche P Module instrument. The Roche method calibrators were ...
Iron-rich SWCNT oxidized ascorbate to its radical. These in vitro results are in line with marked inflammatory response and ... Similarly, superoxide extracellularly generated by xanthine oxidase/xanthine yielded hydroxyl radicals. ...
Ascorbate oxidase [49555] (1 species). consists of three domains of this fold. ...
The breakdown can be catalysed by ascorbate peroxidase (De Gara, 2004) and ascorbate oxidase (De Tullio et al., 2013), while ... Overall, ascorbate efflux stimulates the self-amplifying ROS-Ca2+ hub, which is based on activation of NADPH oxidase by ... Overall, ascorbate efflux stimulates the self-amplifying ROS-Ca2+ hub, which is based on activation of NADPH oxidase by ... In this case, ascorbate- is transported as the counterion to maintain cell ionic and charge balance. Ascorbate accumulation in ...
Wound-responsive element (WRE) found in the promoter region of cucumber ascorbate oxidase gene, CsAAO1; Binding site of ...
like Ascorbate, Catalase, Peroxidase and Superoxide dismutase which scavenge both radicals and related non radical oxygen ...
RT-qPCR analysis of the expression of antioxidant genes (g) SiRbOH (Sesamum indicum respiratory burst oxidase homolog), (h) ... Specific activity of enzyme was expressed as μmol ascorbate oxidized min−1 mg−1 protein. ... Dual role of reactive oxygen species and NADPH oxidase RBOHD in an Arabidopsis-Alternaria pathosystem. Plant Physiology 151, ... RbOH (Respiratory burst oxidase homologs) in plants are directly involved in ROS accumulation and plant susceptibility against ...
... lysyl oxidase (elastin and collagen cross-linking), ascorbate oxidase (skeletal development), monoamine oxidase (possibly ... and cytochrome c oxidase (electron transport and possibly responsible for hypothermia). The resulting defects are reflected in ...
D. Every, W. B. Griffin, and P. E. Wilson, "Ascorbate oxidase, protein disulfide isomerase, ascorbic acid, dehydroascorbic acid ...
... rice miR528 has been shown to play an important role in viral resistance by negatively targeting L-ascorbate oxidase (AO) mRNA ...
... the role of peroxidase and ascorbate oxidase in growth regulation. Часопис. ARCHIVES OF BIOLOGICAL SCIENCES. ... Characterization of polyphenol oxidase changes induced by desiccation of Ramondaserbica leaves. Часопис. Physiol Plant. ... Activities of Class III peroxidase and polyphenol oxidase in fruits of selected tomato genotypes from Gene Bank of Republic of ...
Inhibition of xanthine oxidase and suppression of intracellular reactive oxygen species in HL-60 cells by theafl avin-3,3- ... such as ascorbate, glutathione and cysteine. It also scavenges O2- radicals as demonstrated by using xanthine and xanthine ... Aucamp J, et al, Anticancer Res 1997 Nov-Dec; 17(6D):4381-5 Inhibition of xanthine oxidase by catechins. The liver enzyme, ... Decrease excess production of catabolic sustances such as collagenase, elastase, hyaluronidase, TNF, NOS and xanthine oxidase ( ...
... the deproteinized plasma was treated with acetate buffer and ascorbate oxidase and further derivatized by orthophenyl diamine ...
L-ascorbate oxidase/ copper ion binding / oxidoreductase. F:oxidoreductase activity, L-ascorbate oxidase activity, copper ion ...
... gulonolactone oxidase) that converts blood sugar to ascorbate (vitamin C). [Proceedings National Academy Science Dec 1990; ...
Author Garmash in the review with the title "Suppression of mitochondrial alternative oxidase can result in upregulation of the ... Decreased relative amounts of reduced ascorbate at stable reactive-oxygen-species (ROS) levels owing to compensation in AOX- ... proposes that the decrease in the relative amount of reduced ascorbate at stable ROS levels as a result of compensation in ...
IV and IM ascorbate. Clinically large amounts of ascorbate used intravenously are virucidal. The sodium ascorbate used ... This defect is caused by a mutated defective gene for the liver enzyme, L-gulonolactone oxidase. The higher mammals (except for ... He used sodium ascorbate, 7.5 grams in 30 ml. The syringes are 5 to 60 cc. The needles are 20 gauge (big), one inch long to 31 ... "Sodium ascorbate will cure any type of snake bite." The amounts and the speed of injection are critical. Forty to 60 grams ...
The blue oxidases, ascorbate oxidase, laccase and ceruloplasmin. Modelling and structural relationships. ... L-ascorbate oxidase (EC 1.10.3.3), a higher plant enzyme. *Ceruloplasmin (EC 1.16.3.1) (ferroxidase), a protein found in the ... Both patterns are derived from the same region, which in ascorbate oxidase, laccase, in the third domain of ceruloplasmin, and ... similar to that found in laccase and ascorbate oxidase. In addition to the above enzymes there are a number of proteins which, ...
L-ascorbate oxidase. ... ascorbic acid oxidase, ascorbate oxidase, ascorbic oxidase, ascorbate dehydrogenase, L-ascorbic acid ... Ascorbic AcidDehydroascorbic AcidAntioxidantsL-Gulonolactone OxidaseSodium-Coupled Vitamin C TransportersAscorbate Oxidase2,3- ... Mineral ascorbates. ... the anion of ascorbic acid). Mineral ascorbates are powders manufactured by reacting ascorbic acid with ... Ascorbate Oxidase. An enzyme that converts ascorbic acid to dehydroascorbic acid. EC 1.10.3.3.. ...
Gupta, D. K.; Pena, Liliana Beatriz; Romero Puertas, M. C.; Hernández, A.; Inouhe, M.; et al.; NADPH oxidases differentially ... The role of NADPH oxidases under cadmium (Cd) toxicity was studied using Arabidopsis thaliana mutants AtrbohC, AtrbohD and ... NADPH oxidases differentially regulate ROS metabolism and nutrient uptake under cadmium toxicity ... while glutathione reductase and glycolate oxidase activities increased in Atrboh mutants, and superoxide dismutases were down- ...
L-ascorbate oxidase. EC:1.10.3.3 - 8.331e-38. - Source. KEGGs. Term. Type. e value. Identity. ... Multicopper oxidase, copper-binding site IPR002355 - 0.0. - Sma3. Bacterial extracellular solute-binding family 1, conserved ...
L-ascorbate oxidase, plant type. Members of this protein family are the copper-containing enzyme L-ascorbate oxidase (EC 1.10. ... from plants than to other known ascorbate oxidases. ...
Ascorbate Oxidase (Lyophilized powder) $350.00. $250.00. * Human TWEAK Protein (Highly Pure) $695.00. $495.00. ...
Plant L-ascorbate oxidase. -0.8. 0.34. -0.33. 102. AT1G52230. photosystem I subunit H2. PHOTOSYSTEM I SUBUNIT H-2,. photosystem ... cytochrome c oxidase 15. cytochrome c oxidase 15. 0.82. 0.33. -0.32. 48. AT3G29240. Protein of unknown function (DUF179). -0.82 ... ascorbate peroxidase 4. ascorbate peroxidase 4, thylakoid. lumen 29. -0.8. 0.32. -0.34. ...
Fe(II) ascorbate oxidase. 69. 1e-11. 9064. GAG GGG AAC ACT AAT CAA GCG. TGC CTC AAA TGC TTG CTT TC. 270. 270. Smearh. -. ...
  • Vitamin C (L-ascorbic acid, ascorbate), a water-soluble micronutrient essential for humans, is a six-carbon α-ketolactone weak acid with a pH of 4.2 and a molecular weight of 176 ( Fig. 29.1 ). (basicmedicalkey.com)
  • In enzymology, a L-ascorbate oxidase (EC 1.10.3.3) is an enzyme that catalyzes the chemical reaction 2 L-ascorbate + O2 ⇌ {\displaystyle \rightleftharpoons } 2 dehydroascorbate + 2 H2O Thus, the two substrates of this enzyme are L-ascorbate and O2, whereas its two products are dehydroascorbate and H2O. (wikipedia.org)
  • This enzyme participates in ascorbate metabolism. (wikipedia.org)
  • The systematic name of this enzyme class is L-ascorbate:oxygen oxidoreductase. (wikipedia.org)
  • Laccase (EC 1.10.3.2 ) (urishiol oxidase), an enzyme found in fungi and plants, which oxidizes many different types of phenols and diamines. (expasy.org)
  • L-ascorbate oxidase (EC 1.10.3.3 ), a higher plant enzyme. (expasy.org)
  • Members of this protein family are the copper-containing enzyme L-ascorbate oxidase (EC 1.10.3.3), also called ascorbase. (unl.edu)
  • Vitamin C is not synthesized by humans and nonhuman primates because of their lack of gulonolactone oxidase, the terminal enzyme in the biosynthetic pathway of vitamin C from glucose. (basicmedicalkey.com)
  • Structurally ceruloplasmin exhibits internal sequence homology, and seem to have evolved from the triplication of a copper-binding domain similar to that found in laccase and ascorbate oxidase. (expasy.org)
  • Both patterns are derived from the same region, which in ascorbate oxidase, laccase, in the third domain of ceruloplasmin, and in copA, contains five residues that are known to be involved in the binding of copper centers. (expasy.org)
  • The blue oxidases, ascorbate oxidase, laccase and ceruloplasmin. (expasy.org)
  • 5 Since ascorbate seems to influence the free metal, and since 90-95% of copper found in the serum is bound to ceruloplasmin, some scientists have hypothesized that ascorbate (or citrate) may have an influence on this protein. (naturalcalm.ca)
  • The oxidase activity (i.e., the ability to bind free copper and iron) of ceruloplasmin has been suggested to be lower in the presence of ascorbate in vitro and in animal models. (naturalcalm.ca)
  • The enzymes that belong to this family are laccases, L-ascorbate oxidases, and ceruloplasmin. (expasy.org)
  • In addition to the above enzymes there are a number of other proteins that are similar to the multi-copper oxidases in terms of structure and sequence, some of which have lost the ability to bind copper. (expasy.org)
  • The FET3 gene of S. cerevisiae encodes a multicopper oxidase required for ferrous iron uptake. (expasy.org)
  • Irwin Stone (10, 11, 12) pointed out the potential of vitamin C in the treatment of many diseases, the inability of humans to synthesize ascorbate, and the resultant condition hypoascorbemia. (doctoryourself.com)
  • Guinea pigs, capybaras, bats, and some fish also do not synthesize ascorbate ( 6 ). (basicmedicalkey.com)
  • For all species unable to synthesize ascorbate, it is a vitamin by definition and must be obtained exogenously. (basicmedicalkey.com)
  • There are three spectroscopically different copper centers found in multicopper oxidases: type 1 (or blue), type 2 (or normal) and type 3 (or coupled binuclear). (expasy.org)
  • The role of NADPH oxidases under cadmium (Cd) toxicity was studied using Arabidopsis thaliana mutants AtrbohC, AtrbohD and AtrbohFwhich were grown under hydroponic conditions with 25 and 100 μM Cd for 1 and 5 days. (conicet.gov.ar)
  • and by 64.8% and 91.2%, 21.9% and 72.7%, and 76.7% and 166.7% for enzymes activity including ascorbate peroxidase, glutathione peroxidase, and phenylalanine ammonia-lyase, respectively. (bvsalud.org)
  • This family is found in flowering plants, and shows greater sequence similarity to a family of laccases (EC 1.10.3.2) from plants than to other known ascorbate oxidases. (unl.edu)
  • Apoplastic ascorbate oxidases (AOs) play a critical role in reactive oxygen species (ROS)-mediated innate host immunity by regulating the apoplast redox state. (lsuhsc.edu)
  • These data show that apoplastic redox-active transition metals are involved in the ascorbate-induced [Ca2+]cyt. (deepdyve.com)
  • EPR spectroscopy measurements demonstrate that salinity (NaCl) triggers the accumulation of root apoplastic ascorbyl radicals in an A9C-dependent manner, confirming that l-ascorbate leaks through anion channels under depolarization. (deepdyve.com)
  • This mechanism may underlie ascorbate release, signalling phenomena, apoplastic redox reactions, iron acquisition, and control the ionic and electrical equilibrium (together with K+ efflux via GORK channels). (deepdyve.com)
  • iNOS expression requires NADPH oxidase-dependent redox signaling in microvascular endothelial cells. (umaryland.edu)
  • Similarly, superoxide extracellularly generated by xanthine oxidase/xanthine yielded hydroxyl radicals. (cdc.gov)
  • Copper-dependent metalloenzymes relevant to the clinical phenotype include tyrosinase (pigmentation of skin and hair), lysyl oxidase (elastin and collagen cross-linking), ascorbate oxidase (skeletal development), monoamine oxidase (possibly responsible for pili torti), superoxide dismutase (free-radical detoxification), dopamine beta-hydroxylase (catecholamine production), peptidyl-glycine alpha-amidating mono-oxygenase (bioactivation of peptide hormones), and cytochrome c oxidase (electron transport and possibly responsible for hypothermia). (medscape.com)
  • Cadmium increased catalase activity in WT plants and decreased it in Atrboh mutants, while glutathione reductase and glycolate oxidase activities increased in Atrboh mutants, and superoxide dismutases were down-regulated inAtrbohC. (conicet.gov.ar)
  • Whereas a hampering effect mediated by PGP bacterial inoculation was registered on levels of superoxide anion, hydroxyl radical, electrolyte leakage, and polyphenol oxidase activity, with a decrease of 0.53%, 14.12%, 2.70%, and 5.70%, respectively, under a highest Cd level (150 mg/kg) compared with control plants. (bvsalud.org)
  • SA improved the antioxidant defense in terms of ascorbate peroxidase (APX) and polyphenol oxidase (PPO) activities. (bvsalud.org)
  • Stressful conditions of any kind greatly increase utilization of vitamin C. Ascorbate excreted in the urine drops markedly with stresses of any magnitude unless vitamin C is provided in large amounts. (doctoryourself.com)
  • With loss of the first electron, vitamin C oxidizes to the ascorbate free radical (semidehydroascorbic acid). (basicmedicalkey.com)
  • Reactive free radicals are reduced by vitamin C, and the less reactive ascorbate radical is formed in their place. (basicmedicalkey.com)
  • The interaction of copper and ascorbate (i.e., vitamin C) has been described since the early 1960s. (naturalcalm.ca)
  • Intriguingly, the replacement of gluconate with ascorbate in the patch-clamp pipette reveals a large ascorbate efflux current, which shows sensitivity to the anion channel blocker, anthracene-9-carboxylic acid (A9C), indicative of the ascorbate release via anion channels. (deepdyve.com)
  • In water solutions, this substance is present as a monovalent anion, ascorbate- (Asc-), which easily donates electrons to oxidized molecules and scavenges reactive oxygen species (ROS). (deepdyve.com)
  • Co-evolved Plant And Blast Fungus Ascorbate Oxidases Orchestrate The R" by Jiexiong Hu, Muxing Liu et al. (lsuhsc.edu)
  • L-ascorbate oxidase, plant type. (unl.edu)
  • Exogenous copper and iron stimulate the ascorbate-induced [Ca2+]cyt. (deepdyve.com)
  • However, if doses of ascorbate are not provided to satisfy this potential draw on the nutrient, first local tissues involved in the disease, then the blood, and then the body in general become deplete of ascorbate (ANASCORBEMIA and ACUTE INDUCED SCURVY). (doctoryourself.com)
  • The deficit of ascorbate probably starts in the tissues directly involved in the disease and then spreads to other tissues of the body. (doctoryourself.com)
  • The half-life of the ascorbate radical is long enough to be measured directly by electron paramagnetic resonance, however. (basicmedicalkey.com)
  • The gulonolactose oxidase gene became nonfunctional in a common primate ancestor ( 5 ). (basicmedicalkey.com)
  • Klenner found that viral diseases could be cured by intravenous sodium ascorbate in amounts up to 200 grams per 24 hours. (doctoryourself.com)
  • The patient is thereby put at risk for complications of metabolic processes known to be dependent upon ascorbate. (doctoryourself.com)
  • in the following order: A-A-B-A-C-C. The A-type domain is related to the multicopper oxidases. (expasy.org)
  • Dietary ascorbate has been suggested to interfere with copper absorption in several animal and human studies at high levels. (naturalcalm.ca)
  • Exogenous ascorbate also induces a moderate increase in programmed cell death symptoms in intact roots, but it does not activate Ca2+ influx currents in patch-clamped root protoplasts. (deepdyve.com)
  • In comparison with other free radicals, the ascorbate radical is relatively stable and unreactive. (basicmedicalkey.com)
  • If this massive draw on the small ascorbate stores of the body is not fully satisfied, the condition of ANASCORBEMIA results. (doctoryourself.com)