Distinct characteristics of OxyR2, a new OxyR-type regulator, ensuring expression of Peroxiredoxin 2 detoxifying low levels of hydrogen peroxide inVibrio vulnificus

The nitric oxide synthase-like protein fromBacillus cereus(bcNOS) has been cloned, expressed, and characterized. This small hemeprotein (356 amino acids in length) has a mass of 43 kDa and forms a dimer. The recombinant protein showed similar spectral shifts to the mammalian NOS proteins and could bind the substrates L-arginine andNG-hydroxy-L-arginine as well as the ligand imidazole. Low levels of activity were recorded for the hydrogen peroxide-dependent oxidation ofNG-hydroxy-L-arginine and L-arginine by bcNOS, while a reconstituted system with the rat neuronal NOS reductase domain showed no activity. The recombinant bcNOS protein adds to the complement of bacterial NOS-like proteins that are used for the investigation of the mechanism and function of NO in microorganisms.

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Hydrogen Peroxide Generation of Copper/Ascorbate Formulations on Cotton: Effect on Antibacterial and Fibroblast Activity for Wound Healing Application

Molecules ◽

10.3390/molecules23092399 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2399 ◽

Cited By ~ 4

Author(s):

J. Edwards ◽

Nicolette Prevost ◽

Michael Santiago ◽

Terri von Hoven ◽

Brian Condon ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Wound Healing ◽

Cotton Fiber ◽

Cotton Effect ◽

Aqueous Environment ◽

Amplex Red ◽

Low Levels ◽

Icp Analysis ◽

Hydrogen Peroxide Generation

Greige cotton (unbleached cotton) is an intact plant fiber that retains much of the outer cotton fiber layers. These layers contain pectin, peroxidases, and trace metals that are associated with hydrogen peroxide (H2O2) generation during cotton fiber development. When greige cotton is subjected to a nonwoven hydroentanglement process, components of the outer cotton fiber layers are retained. When hydrated, this fabric can generate H2O2 (5–50 micromolar). This range has been characterized as inducing accelerated wound healing associated with enhanced cell signaling and the proliferation of cells vital to wound restoration. On the other hand, H2O2 levels above 50 micromolar have been associated with bacteriostatic activity. Here, we report the preparation and hydrogen peroxide activity of copper/ascorbate formulations, both as adsorbed and in situ synthesized analogs on cotton. The cooper/ascorbate-cotton formulations were designed with the goal of modulating hydrogen peroxide levels within functional ranges beneficial to wound healing. The cotton/copper formulation analogs were prepared on nonwoven unbleached cotton and characterized with cotton impregnation titers of 3–14 mg copper per gram of cotton. The copper/ascorbate cotton analog formulations were characterized spectroscopically, and the copper titer was quantified with ICP analysis and probed for peroxide production through assessment with Amplex Red. All analogs demonstrated antibacterial activity. Notably, the treatment of unbleached cotton with low levels of ascorbate (~2 mg/g cotton) resulted in a 99 percent reduction in Klebsiella pneumoniae and Staphylococcus aureus. In situ synthesized copper/ascorbate nanoparticles retained activity and did not leach out upon prolonged suspension in an aqueous environment. An assessment of H2O2 effects on fibroblast proliferation are discussed in light of the copper/cotton analogs and wound healing.

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Measurement of Residual Hydrogen Peroxide in Preformed Food Cartons Decontaminated with Hydrogen Peroxide and Ultraviolet Irradiation

Journal of Food Protection ◽

10.4315/0362-028x-46.12.1074 ◽

1983 ◽

Vol 46 (12) ◽

pp. 1074-1077 ◽

Cited By ~ 7

Author(s):

CATHERINE J. STANNARD ◽

JOHN M. WOOD

Keyword(s):

Hydrogen Peroxide ◽

Ultraviolet Irradiation ◽

Food Packaging ◽

Distilled Water ◽

Post Process ◽

Hot Air ◽

Residual Hydrogen ◽

Low Levels ◽

Uv C

A luminometric method was used to determine the levels of residual hydrogen peroxide present in preformed food packaging cartons after a decontamination process using sterile distilled water or 0.1, 1.0 or 30% (wt/vol) hydrogen peroxide and ultraviolet (UV-C, 254 nm) irradiation. The reduction of post-process peroxide levels in the cartons by irradiation or hot air was assessed. A residual hydrogen peroxide level of approx. 100 ppb could be obtained by spraying 0.2 ml of 0.1% hydrogen peroxide into the carton. Treatment with 1% hydrogen peroxide, with or without UV-C irradiation, gave residual levels approximately tenfold higher. The level was not reduced by UV-C irradiation but could be reduced by blowing hot air into the carton. 30% hydrogen peroxide sprayed into cartons could not be reduced by heat to levels below 100 ppb. Extremely low levels of residual hydrogen peroxide were detected when water was sprayed into cartons, both with or without UV-C irradiation.

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Hydrogen peroxide dependent interaction of peroxiredoxin 2 with ERp46

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2012.08.440 ◽

2012 ◽

Vol 53 ◽

pp. S210

Author(s):

P.E. Pace⁎ ◽

A.V. Peskin ◽

M.B. Hampton ◽

C.C. Winterbourn

Keyword(s):

Hydrogen Peroxide ◽

Peroxiredoxin 2 ◽

Dependent Interaction

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The Removal of Low Levels of Organics from Aqueous Solutions Using Fe(II) and Hydrogen Peroxide Formed In Situ at Gas Diffusion Electrodes

Journal of The Electrochemical Society ◽

10.1149/1.1392039 ◽

1999 ◽

Vol 146 (8) ◽

pp. 2983-2989 ◽

Cited By ~ 104

Author(s):

Tomás Harrington ◽

Derek Pletcher

Keyword(s):

Hydrogen Peroxide ◽

Aqueous Solutions ◽

Gas Diffusion ◽

Gas Diffusion Electrodes ◽

Low Levels

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Dual Role of Hydrogen Peroxide in Arabidopsis Guard Cells in Response to Sulfur Dioxide

Advances in Toxicology ◽

10.1155/2014/407368 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Huilan Yi ◽

Xin Liu ◽

Min Yi ◽

Gang Chen

Keyword(s):

Hydrogen Peroxide ◽

Cell Death ◽

Sulfur Dioxide ◽

Nadph Oxidase ◽

Stomatal Closure ◽

Critical Role ◽

Guard Cells ◽

Oxidase Inhibitor ◽

Air Pollutant ◽

Low Levels

Sulfur dioxide (SO2) is a major air pollutant and has significant impacts on plant physiology. Plant can adapt to SO2 stress by controlling stomatal movement, gene expression, and metabolic changes. Here we show clear evidences that SO2-triggered hydrogen peroxide (H2O2) production mediated stomatal closure and cell death in Arabidopsis leaves. High levels of SO2 caused irreversible stomatal closure and decline in guard cell viability, but low levels of SO2 caused reversible stomatal closure. Exogenous antioxidants ascorbic acid (AsA) and catalase (CAT) or Ca2+ antagonists EGTA and LaCl3 blocked SO2-induced stomatal closure and decline in viability. AsA and CAT also blocked SO2-induced H2O2 and [Ca2+]cyt elevation. However, EGTA and LaCl3 inhibited SO2-induced [Ca2+]cyt increase but did not suppress SO2-induced H2O2 elevation. These results indicate that H2O2 elevation triggered stomatal closure and cell death via [Ca2+]cyt signaling in SO2-stimulated Arabidopsis guard cells. NADPH oxidase inhibitor DPI blocked SO2-induced cell death but not the stomatal closure triggered by low levels of SO2, indicating that NADPH oxidase-dependent H2O2 production plays critical role in SO2 toxicity but is not necessary for SO2-induced stomatal closure. Our results suggest that H2O2 production and accumulation in SO2-stimulated plants trigger plant adaptation and toxicity via reactive oxygen species mediating Ca2+ signaling.

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Peroxiredoxin 1 plays a primary role in protecting pancreatic β-cells from hydrogen peroxide and peroxynitrite

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00011.2020 ◽

2020 ◽

Vol 318 (5) ◽

pp. R1004-R1013 ◽

Cited By ~ 6

Author(s):

Jennifer S. Stancill ◽

John T. Happ ◽

Katarzyna A. Broniowska ◽

Neil Hogg ◽

John A. Corbett

Keyword(s):

Hydrogen Peroxide ◽

Oxidative Damage ◽

Defense Mechanism ◽

Autoimmune Diabetes ◽

Cell Damage ◽

Thioredoxin Reductase ◽

Primary Role ◽

Β Cells ◽

Peroxiredoxin 1 ◽

Low Levels

Both reactive nitrogen and oxygen species (RNS and ROS), such as nitric oxide, peroxynitrite, and hydrogen peroxide, have been implicated as mediators of pancreatic β-cell damage during the pathogenesis of autoimmune diabetes. While β-cells are thought to be vulnerable to oxidative damage due to reportedly low levels of antioxidant enzymes, such as catalase and glutathione peroxidase, we have shown that they use thioredoxin reductase to detoxify hydrogen peroxide. Thioredoxin reductase is an enzyme that participates in the peroxiredoxin antioxidant cycle. Peroxiredoxins are expressed in β-cells and, when overexpressed, protect against oxidative stress, but the endogenous roles of peroxiredoxins in the protection of β-cells from oxidative damage are unclear. Here, using either glucose oxidase or menadione to continuously deliver hydrogen peroxide, or the combination of dipropylenetriamine NONOate and menadione to continuously deliver peroxynitrite, we tested the hypothesis that β-cells use peroxiredoxins to detoxify both of these reactive species. Either pharmacological peroxiredoxin inhibition with conoidin A or specific depletion of cytoplasmic peroxiredoxin 1 ( Prdx1) using siRNAs sensitizes INS 832/13 cells and rat islets to DNA damage and death induced by hydrogen peroxide or peroxynitrite. Interestingly, depletion of peroxiredoxin 2 ( Prdx2) had no effect. Together, these results suggest that β-cells use cytoplasmic Prdx1 as a primary defense mechanism against both ROS and RNS.

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