Becomes cycle ascorbate and h2o2 ascorbate peroxidases. Medical search. Frequent questions

The FHA cycle is active inside the cell, detoxifying superoxide anion radicals (O2·-), which are mainly generated as a result of so-called 'electron leakage' to triplet oxygen (O2) in photosynthetic, mitochondrial, peroxisomal, and probably other electron transport chains (Ozyigit et al. (deepdyve.com)
Biochemistry bioassays confirmed the involvement of monooxygenase enzyme, carboxylesterase, superoxide dismutase and peroxidase in multi-insecticide resistance mechanism. (preprints.org)
Abstract Rapid generation of superoxide and accumulation of H2O2 is a characteristic early feature of the hypersensitive response following perception of pathogen avirulence signals. (rehabsociety.org.hk)
The activity of antioxidant enzymes (catalase, superoxide dismutase, peroxidase, ascorbate-peroxidase and glucose-6-phosphate dehydrogenase) and the amount of non-enzymatic compounds (malondialdehyde and thiol) significantly decerased in the third and the fourth instar larvae of H. variegata on the micronutrient treatments compared to control. (ac.ir)
The increase of superoxide dismutase activity can indicate the occurrence of oxidative stress in the body of the third and the fourth instar larvae of predator H. variegata could be assigned to the accumulation of H2O2 in the body of M. persicae under the influence of the defensive secondary metabolites, which led to increase the activity of catalase and peroxidase. (ac.ir)
These results, together with previous data, suggest that the network of transcriptional control explains how CATs and other scavenger enzymes such as peroxidase and superoxide dismutase may be coordinately regulated during development, but differentially expressed in response to different stresses for controlling ROS homeostasis. (jipb.net)
In the human cell, antioxidant molecules include both nonenzymatic compounds such as glutathione (GSH), thioredoxin (Trx), ascorbate, α -tocopherol, β -carotene, and coenzyme Q10 and enzymes such as catalase, glutathione peroxidase, and superoxide dismutase (SOD) [ 8 ]. (hindawi.com)

The systematic name of this enzyme class is L-ascorbate:hydrogen-peroxide oxidoreductase. (wikipedia.org)
The ascorbate-glutathione cycle (Halliwell-Asada pathway) may operate to reduce hydrogen peroxide (H2O2). (ristudypost.com)
Germination of selected vegetable seeds including corn (Zea mays L.), squash (Cucurbita pepo L.), and tomato (Solanum lycopersicum L.) was studied in water with different concentrations of hydrogen peroxide (H2O2) solution ranging from 0, 0. (researchgate.net)
The use of hydrogen peroxide (H2O2) is recently recommended for use in drip irrigation particularly for cleaning of drip emitters. (researchgate.net)
In Arabidopsis, catalase (CAT) genes encode a small family of proteins including CAT1, CAT2 and CAT3, which catalyze the decomposition of hydrogen peroxide (H2O2) and play an important role in controlling homeostasis of reactive oxygen species (ROS). (jipb.net)

Under physiological conditions, the immediate product of the reaction, the monodehydroascorbate radical, is reduced back to ascorbate by a monodehydroascorbate reductase (monodehydroascorbate reductase (NADH)) enzyme. (wikipedia.org)

Other names in common use include L-ascorbic acid peroxidase, L-ascorbic acid-specific peroxidase, ascorbate peroxidase, and ascorbic acid peroxidase. (wikipedia.org)

but if the ascorbate/dehydroascorbate (AA/DHA) ratio is kept high (the redox potential kept reducing) until the unstable dehydro- ascorbate undergoes hydrolysis or can be reduced back to ascorbate, the dehydroascorbate will do no harm. (mall-net.com)

Ascorbate peroxidase (or L-ascorbate peroxidase, APX) (EC 1.11.1.11) is an enzyme that catalyzes the chemical reaction L-ascorbate + H2O2 ⇌ {\displaystyle \rightleftharpoons } dehydroascorbate + 2 H2O It is a member of the family of heme-containing peroxidases. (wikipedia.org)

APX enzymes show high specificity for ascorbate as an electron donor, but most APXs will also oxidise other organic substrates that are more characteristic of the class III peroxidases (such as horseradish peroxidase), in some cases at rates comparable to that of ascorbate itself. (wikipedia.org)
Genes coding for enzymes of the lipid degradation pathway are repressed by anoxia, mostly at the level of lipases, while the genes encoding b-oxidation and the glyoxylate cycle genes are unaffected or moderately induced by anoxia. (ristudypost.com)

Exposure to Se or mimosine exhibited a differential response in the mitochondrial catalase and ascorbate peroxidase (Asc-Px) activities. (typeset.io)

These data show that apoplastic redox-active transition metals are involved in the ascorbate-induced [Ca2+]cyt. (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)
For instance, the redox probe DCFH continues to be utilized to imply intracellular Mito-SOX and H2O2 to point mitochondria-derived O2B? (vittori-lab.com)
Furthermore, artifactual development of H2O2 happens from redox bicycling from the DCF radical (33, 34). (vittori-lab.com)

Some proteins from the APX family lack the ascorbate-binding amino acid residues suggesting that they might oxidize other molecules than ascorbate. (wikipedia.org)
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)
2016) also suggested that H2O2 molecules play dual roles in plant physiological and developmental processes. (researchgate.net)

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)

Since even at very high doses, ascorbate is virtually nontoxic, it may be given in the enormous doses necessary to quench almost all unwanted free radicals and oxidants. (mall-net.com)
H2O2, or peroxidase-derived oxidants (24,C26). (vittori-lab.com)

Heme peroxidases catalyse the H2O2-dependent oxidation of a wide range of different, usually organic, substrates in biology. (wikipedia.org)
APXs catalyse the H2O2-dependent oxidation of ascorbate in plants, algae and certain cyanobacteria. (wikipedia.org)
Many of these types are short-lived, respond quickly with low-molecular pounds mobile reductants (ascorbate and GSH), and will trigger oxidation of important cellular elements (lipid, proteins, and DNA). (vittori-lab.com)
However, we while others show that intracellular oxidation of DCFH towards the green fluorescent item dichlorofluorescein (DCF) can be catalyzed by peroxidases or via intracellular iron-dependent systems (30,C32). (vittori-lab.com)
The enhanced effects on germination with H2O2 have a) been reported for seed with pathogenic infestations (Szopniska, 2014) i.e. a biocidal effect, and b) mediated through the oxidation of germination inhibitors present in the seed coat or/and in the pericarp, i.e. a seed treatment effect. (researchgate.net)
Inflammation often exacerbates the oxidative stress, creating a self-perpetuating, vicious cycle of oxidation and inflammation [ 20 , 21 ]. (hindawi.com)
There are a number of reactive nitrogen oxide species, such as N2O3 and ONOO-, that can alter critical cellular components under high local concentrations of NO. However, NO can also abate the oxidation chemistry mediated by reactive oxygen species such as H2O2 and O2- that occurs at physiological levels of NO. In addition to the antioxidant chemistry, NO protects against cell death mediated by H2O2, alkylhydroperoxides, and xanthine oxidase. (researchgate.net)

an oxidative burst triggered by the treatment of Arabidopsis plants with a cell wall elicitor prepared from the fungus Fusarium oxysporum could be abolished by knocking down the transcript levels of PRX33 and PRX34 through the transgenic expression of a French bean class III peroxidase cDNA (FBP1) in an antisense orientation (Daudi et al. (rehabsociety.org.hk)

Clinically, in a disease ameliorated by ascorbate, there is a suppression of symptoms only with very high doses and approximately to that extent which a nonrate-limited,_antioxidant_free_radical_scavenger, might be expected to affect that disease process if all harmful free radicals and highly reactive oxidizing substances were quenched. (mall-net.com)

The binding interaction of soybean cytosolic APX with its physiological substrate, ascorbate, and with a number of other substrates are also known. (wikipedia.org)

Moreover, this study has elucidated that SA‐induced stomatal closure involves extracellular oxidative burst (Figs 2 & 3) and that the extracellular oxidative burst is mediated with SHAM‐sensitive peroxidases but not NAD(P)H oxidases (Figs 1d & 2). (rehabsociety.org.hk)
Nitric oxide alleviates aluminum-induced oxidative damage through regulating the ascorbate-glutathione cycle in roots of wheat [J]. J Integr Plant Biol. (jipb.net)

This enzyme participates in ascorbate and aldarate metabolism. (wikipedia.org)
2016). AA also takes part in the regeneration of α-tocopherol (vitamin E) in photosynthetic membranes and participates in chloroplast metabolism as a cofactor for violaxanthin de-epoxidase, an enzyme involved in xanthophyll cycle-mediated photoprotection (Smirnoff and Wheeler, 2000). (deepdyve.com)

Peroxides oxidize the C P -SH to cysteine sulfenic acid (C P ?SOH), which then reacts with another cysteine residue, named the "resolving" Cys (C R ) to form a disulfide that is subsequently reduced by an appropriate electron donor to complete a catalytic cycle. (molcells.org)

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)

This enzyme belongs to the family of oxidoreductases, specifically those acting on a peroxide as acceptor (peroxidases). (wikipedia.org)

The objective of this research is to identify genes associated to desiccation-rehydration cycle in the transcriptome of H. cruentum to better understand the genetic dynamics behind its desiccation tolerance mechanism. (frontiersin.org)

Ascorbate-dependent peroxidase activity was first reported in 1979,, more than 150 years after the first observation of peroxidase activity in horseradish plants and almost 40 years after the discovery of the closely related cytochrome c peroxidase enzyme. (wikipedia.org)
Peroxidases have been classified into three types (class I, class II and class III): ascorbate peroxidases is a class I peroxidase enzyme. (wikipedia.org)
APX has high sequence identity to cytochrome c peroxidase, which is also a class I peroxidase enzyme. (wikipedia.org)
This means that defining an enzyme as an APX is not straightforward, but is usually applied when the specific activity for ascorbate is higher than that for other substrates. (wikipedia.org)

Mixtures of mineral ascorbates (calcium, magnesium, potassium, zinc, and sometimes sodium) are used in certain circumstances to increase bowel tolerance for even more clinical effectiveness but do not clearly demonstrate the increasing bowel tolerance phenomenon being discussed here. (mall-net.com)

H2O [3] In ascorbate peroxidase, Compound I is a transient (green) species and contains a high-valent iron species (known as ferryl heme, FeIV) and a porphyrin pi-cation radical,, as found in horseradish peroxidase. (wikipedia.org)

Peroxidase activity registered a significant increase by threefold in mitochondria and fourfold in soluble fraction in both Se and mimosine groups. (typeset.io)

Low or moderate doses (doses substantially below bowel tolerance) usually had no noticeable immediate beneficial effects, but high doses (doses just below the amount that would produce diarrhea in a patient tolerant to ascorbate) would have the effect of markedly suppressing symptoms as the high dose levels were reached. (mall-net.com)

Which of the following is a anapleurotic reaction that occurs in the TCA cycle? (mockdocs.org)

showed that the effect of H2O2 on corn seed germination was significantly greater than for seed treated with aerated water but no H2O2. (researchgate.net)

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)

It is as if a threshold were reached at which point the ascorbate becomes very effective. (mall-net.com)

Polyphenol oxidase and peroxidase in apple leaves inoculated with a virulent or an avirulent strain for Erwinia amylovora . (ac.ir)

The wide spectrum of infectious diseases ameliorated by massive doses of ascorbate indicates some common pathologic processes in these diseases. (mall-net.com)
An early study by Narimanov (2000) reported enhanced germination, emergence and development of seedlings using a short seed soaking treatment with H2O2 in a wide variety of crops including corn (Zea mays L.), beans (Phaseolus sp. (researchgate.net)

H2O2 increases germination rates by breaking down the seed coat, thus allowing the seed to take in oxygen more quickly. (researchgate.net)

tested 24-h seed pre-treatments with H2O2 with 50 mM being optimal with improved seed germination, seedling vigour and growth in corn, squash (Cucurbita pepo L.) and tomato (Solanum lycopersicum L.). Increased germination and seedling growth of peas (Pisum sativum L. 'Alaska') was shown by Barba-Espin et al. (researchgate.net)

Our results reveal that CAT1 is an important player in the removal of H2O2 generated under various environmental stresses. (jipb.net)

Anatomy8

Organisms12

Diseases2

Chemicals and Drugs30

Phenomena and Processes13

Technology, Industry, Agriculture4

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Superoxide7

Hydrogen peroxide5

Monodehydroascorbate reductase1

Ascorbic acid1

Back to ascorbate1

Dehydroascorbate1

Enzymes2

Catalase1

Redox4

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Oxidation7

Arabidopsis1

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Peroxide1

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Enzyme4

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Heme1

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