• KSBB Journal
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• v.13 no.3
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• pp.223-230
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• 1998

Experiments for lignin peroxidase production have been conducted by aerobic fermentation of Phanerochaete chrysosporium under low shear rate and enriched oxygen environment. The result of flask cultures of white rot fungus indicated that high oxygen concentration and low shear force were essential for enhancement of lignin peroxidase production. Pentachlorophenol was readily degraded by lignin peroxidase produced in nutrient limited flask cultures. Polyurethane foam was fond to be an effective immobilization matrix of P. chrysosporium.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.67-71
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• 2001

Effects of exposure to a neurotoxicant, fenitrothion on antioxidant enzyme activities in Chironomus riparius Mg. (Diptera, Chironomidae) larvae were evaluated under laboratory conditions. Exposure to this chemical led to an increase of cupper, zinc type superoxide dismutase and manganese type superoxide dismutase activities and to a decrease of glutathion peroxidase activity. An activation of catalase was observed in the larvae exposed to high fenitrothion concentration. The response of superoxide dismutase was rapid and sensitive to low chemical concentrations, but changes in catalase, total peroxidase and glutathion peroxidase were less sensitive. In this study, antioxidant enzyme activities in Chironomus riparius larvae were identified as pertinent biomarkers for environmental monitoring.

• BMB Reports
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• v.32 no.2
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• pp.168-172
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• 1999

We previously reported that a novel thiol peroxidase (p20) from Escherichia coli is a distinct periplasmic peroxidase that detoxifies hydroperoxides together with glutathione or thioredoxin. Until now, there was no experimental evidence for the presence of thioredoxin (Trx) in the periplasmic space. In an attempt to confirm the physiological function of p20 as a thiol peroxidase supported by Trx in the periplasmic space, we have purified a Trx activity from the periplasmic space of Escherichia coli and identified the Trx as the same protein as the cytoplasmic Trx. The presence of Trx in the periplasmic space of Escherichia coli suggests that p20 is a unique extracellular Trx-linked thiol peroxidase.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.966-971
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• 2009

Peroxidase from Coprinus cinereus (CiP) has attracted attention for its high specific activity and broad substrate spectrum compared with other peroxidases. In this study, the functional expression of this peroxidase was successfully achieved in the methylotrophic yeast Pichia pastoris. The expression level of CiP was increased by varying the microbial hosts and the expression promoters. Since a signal sequence, such as the alpha mating factor of Saccharomyces cerevisiae, was placed preceding the cDNA of the CiP coding gene, expressed recombinant CiP (rCiP) was secreted into the culture broth. The Mut Pichia pastoris host showed a 3-fold higher peroxidase activity, as well as 2-fold higher growth rate, compared with the $Mut^s $ Pichia pastoris host. Furthermore, the AOX1 promoter facilitated a 5-fold higher expression of rCiP than did the GAP promoter.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.273-279
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• 1998

The ability of bovine intact red blood cells to scavenge superoxide and hydrogen peroxide by superoxide dismutase, catalase and glutathione peroxidase was investigated. Intact red cells(up to 0.4%) suspensions did not inhibit ferricytochrome c reduction by superoxide in the superoxide generating system. On the other hand, intact red cell(0.4%) suspensions almost completely inhibit ferrocytochrome c oxidation by hydrogen peroxide. The ability of intact red cells to scavenge hydrogen peroxide was mainly attributed to either membrane bound catalase or glutathione peroxidase. The scavenge of hydrogen peroxide by 0.1~0.2% intact red cells showed a trend of dependence on mainly glutathione peroxidase. However, at blood cell concentration higher than 0.3%, the process depended upon peroxidase-independent scavengers like catalase. Enhancement of ferrocytochrome c oxidation by red cells treated with aminotriazole proved that the protection against hydrogen peroxide was due to catalase, while the protection in the presence of glutathione indicated scavenging effect of glutathione peroxidase against hydrogen peroxide.

• The Journal of Natural Sciences
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• v.15 no.1
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• pp.57-67
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• 2005

In Order to investigate the physiological role of thiol peroxidase in Bacillus subtilis, a thiol peroxidase (btpx) knock-out mutant was generated by homologous recombination. The growth of btpx knock-out mutant in aerobic condition showed a similar pattern with that of wild type of Bacillus subtilis 168/ But btpx knock-out mutant showed a retarded growht in response to oxidative stress such as $H_2O_2$, cumene hydroperoxide (CHP) treatments.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.218-223
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• 1995

Veratryl alcohol which has been reported as an inducer for lignin peroxidase showed different effects on the enzyme biosynthesis in Phanerochaete chrysosporium depending on the addition time. Enzyme expression was optimally induced by adding veratryl alcohol when the carbon source began to be depleted. Hydrogen peroxide, to some extent, stimulated production of lignin peroxidase, but beyond a certain concentration, inactivated lignin peroxidase. Tween 80 induced the formation of small pellets, which were resistant to the deactivation by shear stress. Lignin peroxidase production was increased twice compared with that of the control by adopting all the optimal factors in the culture system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.270-273
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• 1989

This study was carried out to know the physiological characteristics related to flooding tolerance of rice plants. Peroxidase specific activities and banding pattern of peroxidase isozyme of 24 days old seedlings were analyzed after 3 days of flooding treatment in the artificial flooding tank. Peroxidase activities of japonica rice varieties which were relatively susceptible to submergence were higher in comparison to those of Tongil and indica rice varieties. And a peculier band of peroxidase isozyme which was not shown in any part of rice plant if not flooded, was appeared at the around 9 of isoelectric point in the leaf blade of japonica rice varieties when flooded.

• Journal of Plant Biology
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• v.29 no.4
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• pp.233-242
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• 1986

In order to pursue some physiological studies on organogenesis in ginseng tissue culture, ginseng root explants were cultured on a modified MS medium containing NAA and kinetin. The activities of peroxidase and some enzymes were investigated and their isoenzyme patterns were also observed. The activity of peroxidase decreased by 20% in one week's culture and increased thereafter by 80% in culturing for 7 weeks compared with the control group. Glucose-6-phosphate dehydrogenase activity increased by 400% after culturing for 5 weeks and increased during the days preceeding root formation. The activities of glutamate dehydrogenase and acid phosphatase also increased during the culture. After 3 weeks' culture, new peroxidase isozyme (pH 7.6) appeared and 7 weeks' culture, another new peroxidase isozyme (pH unidentified) appeared. These patterns were also identified by using FPLC. After 7 weeks' culture, a new esterase isozyme of pH 8.5 appeared and isozyme patterns of acid phosphatase were quite changed compared with the isozyme patterns of tissue cultured for 5 weeks. In so far as these new isoenzymes appear distinctively after 7 weeks' culture, root differentiation is supposed to be induced after 7 weeks' culture.

• Plant Resources
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• v.8 no.2
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• pp.155-160
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• 2005

A full-length cDNA (PPrx1) encoding peroxidase has been isolated and its nucleotide sequence determined from flower bud in ginseng plant (Panax ginseng). A PPrx1 cDNA is 1192 nucleotides long and has an open reading frame of 1062 bp with a deduced amino acid sequence of 354 residues (pI 7.53). The deduced amino acid sequence of PPrx1 matched to the previously reported peroxidase protein genes. The PPrx1 showed a high similarity with the $64\%$ identity with peroxidase of N. tabacum (AAK52084). In the phylogenetic analysis based on the amino acid residues, the PPrx1 was closer with peroxidase of G. max (AAD37376).