• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.181-189
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• 2018

Candida albicans is a major pathogenic fungus in humans, and meets at first the innate immune cells, such as macrophages, in its host. One important strategy of the host cell to kill C. albicans is to produce reactive oxygen species (ROS) by the macrophages. In response to ROS produced by the macrophages, C. albicans operates its defense mechanisms against them by expressing its oxidative stress response genes. Although there have been many research studies explaining the specific transcription factors and the expression of the oxidative stress genes in C. albicans, the regulation of the oxidative stress genes by chromatin structure is little known. Epigenetic regulation by the chromatin structure is very important for the regulation of eukaryotic gene expression, including the chromatin structure dynamics by histone modifications. Among various histone modifications, histone acetylation is reported for its direct relationship to the regulation of gene expression. Recent studies reported that histone acetyltransferases regulate genes to respond to the oxidative stress in C. albicans. In this review, we introduce all histone acetyltransferases that C. albicans contains and some papers that explain how histone acetyltransferases participate in the oxidative stress response in C. albicans.

• Food Engineering Progress
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• v.21 no.1
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• pp.49-56
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• 2017

Vegetable seed oils (VSOs) have been extracted and used not only as ingredients in food and as sources of dietary lipids, but also as sources of nutraceuticals used to overcome the various oxidative stresses that contribute to the development of diseases, including cancer and other chronic conditions. The chemical compositions and oxidative stabilities of various VSOs were therefore investigated; samples were stored for 35 d, with each oil having been tested under $O_2$ exposure, sealed from $O_2$ exposure and sealed from $O_2$ exposure while containing $O_2$ scavengers. Oxidative stability was evaluated by peroxide value (POV), p-anisidine value (p-AnV), iodine value (IV), and thiobarbituric acid (TBA) value. Perilla seed and flaxseed oil were mostly composed of linolenic acid (45.5% and 59.7%, respectively), whereas pine seed oil was mostly composed of linoleic acid (48.3%). Meanwhile, camellia seed and olive oils contained 80% oleic acid, which correlated strongly with oxidative stability. The POV, p-AnV, and TBA values were the highest under $O_2$ exposure, and the lowest in the presence of $O_2$ scavengers. These results indicate that VOS oxidative stability depends not only on storage conditions, but on unsaturated fatty acid profiles as well.

• Journal of Microbiology
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• v.41 no.3
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• pp.248-251
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• 2003

Glutathione (GSH) is an important factor in determining tolerance against oxidative stress in living organisms. It is synthesized in two sequential reactions catalyzed by ${\gamma}$-glutamylcysteine synthetase (GCS) and glutathione synthetase (GS) in the presence of ATP. In this work, the effects of three different oxidative stresses were examined on GSH content and GSH-related enzyme activities in the fission yeast Schizosaccharomyces pombe. GSH content in S. pombe was significantly enhanced by treatment with hydrogen peroxide, ${\beta}$-naphthoflavone (BNF) and tert-butylhydroquinone (BHQ). Simultaneously, they greatly induced GCS and GS activity. However, they did not have any effects on glutathione reductase activity. These results suggest that GCS and GS activities in S. pombe are up-regulated by oxidative stress.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.5
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• pp.368-376
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• 2005

Coolant rubber hoses for automobile radiators can be degraded and thus failed due to the influence of contacting stresses of air and coolant liquid under thermal and mechanical loadings. In this study, for EPDM(ethylene-propylene diene monomer) rubber conventionally used as a radiator hose material the aging behaviors of the skin part due to thermo-oxidative and electro-chemical stresses were nondestructively evaluated. Through the thermo-oxidative aging test, it was shown that the surface hardness IRHD(International Rubber Hardness Degrees) of the rubber increased with a considerable reduction of failure strain. On account of the penetration of coolant liquid into the skin part the weight of rubber specimens degraded by electro-chemical degradation(ECD) test increased, whereas their. failure strain and IRHD hardness decreased largely. The penetration of coolant liquid seemed to induce some changes in inner structure and micro hardness distribution of the rubbers. Consequently, EPDM rubbers degraded by thermo-oxidative aging and ECD could be characterized nondestructively by micro-hardness and chemical structure analysis methods.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.79-84
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• 1999

Oxidative stress is one of the major environmental stresses to plants. Reactive oxygen species (ROS) generated during metabolic processes damage cellular functions and consequently lead to cell death. Fortunately plants have in vivo defense system by which the ROS is scavenged by enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX). In attempts to understand the protection mechanism of plant against oxidative stress, we developed transgenic tobacco (Nicotiana tabacum cv. Xanthi) plansts thet expressed both SOD and APX in chloroplast using Agrobacterum-mediated transformation and evaluated their protection capabilities against methyl viologen (MV, paraquat) -mediated oxidative damage. Three double transformants (CAI, CA2, and CA3) expressed the chimeric CuZnSOD and chimeric APX in chloroplast, and one transformant (AM) expressed the chimeric APX and chimeric MnSOD in chloroplast. In addition, we obtained three lines of transformants (C/Al, C/A2, and A/C) that expressed the APX and SOD than control plants, and more resistant to oxidative stress caused by MV. TRansformants (C/A and A/C) overexpressing MnSOD, CuZnSOD and APX at the same time showed the highest resistance to MV-mediated oxidative stress among the transformants.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.678-679
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• 2006

• BMB Reports
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• v.42 no.9
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• pp.611-616
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• 2009

We investigated the expression pattern of dehydration responsive element-binding protein-3 in tomato under different abiotic stresses. Full length LeDREB3 cDNA was isolated from tomato plant, followed by phylogenetic analysis based on deduced amino acid sequences that revealed significant sequence similarity to DREB proteins belonging to diverse families of plant species. Southern blot analysis showed duplicate copies of LeDREB3 in the tomato genome while organ-specific expression profiling indicated constitutive expression of LeDREB3 in all tested organs, which was particularly strong in flower. LeDREB3 expression was significantly induced by Nacl, drought, low temperature and $H_2O_2$. Moreover, LeDREB3 was slightly regulated by treatment with ABA and MV. These observations suggest that the LeDREB3 gene may be involved in the response of the tomato plant to stress.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.39-39
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• 2003

Antioxidant enzyme genes play a key role in cell defense against the lethal effects of oxidative stresses in animals and have an essential function which has allowed the evolution of aerobic respiration starting from an ancient form of oxygen-insensitive life. Piscine antioxidant enzymes are also involved in the rapid response to various toxic chemicals as well as many biological stresses, indicating that they could be used as biomarkers for health and aquatic environment. With the purpose for developing fine molecular probing tool to assess the stresses in marine fish, we identified three major antioxidant enzyme genes (superoxide dismutase, catalase and glutathione-S-transferase) from Korean rock bream using expressed sequence tag analysis and/or high density filter screening. Here we report the molecular information on these gene transcripts including complete sequence data and expression profiles.

• Proceedings of the Korean Reliability Society Conference
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• 2006.05a
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• pp.27-31
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• 2006

Rubber hoses for automobile radiators are apt to degraded and thus failed due to the influence of contacting stresses of air and coolant liquid under thermal and mechanical loadings. The aging behaviors of the skin part of the hoses due to thermo-oxidative and electro-chemical stresses were experimentally analyzed. Through the thermo-oxidative aging test, it was shown that the surface hardness IRHD(International Rubber Hardness Degrees) of the rubber increased with a considerable reduction of failure strain as the aging time and temperature were large. On account of the penetration of coolant liquid into the skin part the weight of rubber specimens influenced by electro-chemical degradation (ECD) test increased, whereas their failure strain and IRHD hardness decreased. The hardness decreased further as the test site on the hose skin approached to the negative pole.

• Molecules and Cells
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• v.27 no.1
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• pp.67-74
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• 2009

Autophagy degrades toxic materials and old organelles, and recycles nutrients in eukaryotic cells. Whereas the studies on autophagy have been reported in other eukaryotic cells, its functioning in plants has not been well elucidated. We analyzed the roles of OsATG10 genes, which are autophagy-related. Two rice ATG10 genes - OsATG10a and OsATG10b - share significant sequence homology (about 75%), and were ubiquitously expressed in all organs examined here. GUS assay indicated that OsATG10b was highly expressed in the mesophyll cells and vascular tissue of younger leaves, but its level of expression decreased in older leaves. We identified T-DNA insertional mutants in that gene. Those osatg10b mutants were sensitive to treatments with high salt and methyl viologen (MV). Monodansylcadaverine-staining experiments showed that the number of autophagosomes was significantly decreased in the mutants compared with the WT. Furthermore, the amount of oxidized proteins increased in MV-treated mutant seedlings. These results demonstrate that OsATG10b plays an important role in the survival of rice cells against oxidative stresses.