• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.439-448
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• 2007

The purpose of this study was to investigate the seasonal variations of sediment oxygen demand (SOD) in Lake Paldang and Lake Chungju of the Han River system and to suggest SOD values as parameters for the water quality prediction models of two lakes. SOD was measured at laboratory using sediment collected at 2 sites in Lake Paldang from June to November and at 4 sites in Lake Chungju from May to November in 2005, respectively. It was found from the laboratory test that the SOD in Lake Paldang ranged from 337.8 to 881.0 mg $O_2m^{-2}d^{-1}$ and in Lake Chungju ranged from 143.0 to 969.1 mg $O_2m^{-2}d^{-1}$. The SOD of Lake Paldang showed similar variations to the content of organic matter of sediment. The SOD of Lake Chungju was positively correlated with temperature (r=0.78, p<0.01), $PO_4-P(r=0.79,\;p<0.01)$, TP (r=0.55, p<0.05), DTP (r=0.55, p<0.05), $NO_3-N$ (r=(0.72, p<0.01) of hypolimnetic water. These results indicate that the SOD of Lake Paldang was affected by the content and origin of organic matter of sediment and the SOD of Lake Chungju was closely correlated with physical and chemical factors.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.70-79
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• 2014

In an attempt to develop a variety of expression vector systems for Corynebacterium glutamicum, six types of promoters, including $P_{tac}$, $P_{sod}$, $P_{sod}$ with a conserved Shine-Dalgarno (SD) sequence from C. glutamicum, $P_{ilvC}$, $P_{ilvC}$ with a conserved SD-1 ($P_{ilvC-M1}$), and $P_{ilvC}$ with a conserved SD-2 ($P_{ilvC-M2}$), were cloned into a modified shuttle vector, pCXM48. According to analysis of promoter strength by quantitative reverse transcription PCR, $P_{sod}$ and $P_{sod-M}$ were superior to tac and ilvC promoters in terms of transcription activity in C. glutamicum. All of the promoters have promoter activities in Escherichia coli, and $P_{sod-M}$ displayed the highest level of transcriptional activity. The protein expression in constructed vectors was evaluated by measuring the fluorescence of green fluorescent protein (GFP) and SDS-PAGE. C. glutamicum harboring plasmids showed GFP fluorescence with an order of activity of $P_{ilvC}$ > $P_{ilvC-M1}$ > $P_{sod}$ > $P_{ilvC-M2}$ > $P_{sod-M}$, whereas all plasmids except pCSP30 with $P_{sod}$ displayed fluorescence activities in E. coli. Of them, the strongest level of GFP was observed in E. coli with $P_{sod-M}$, and this seems to be due to the introduction of the conserved SD sequence in the translational initiation region. These results demonstrate that the expression vectors work well in both C. glutamicum and E. coli for the expression of target proteins. In addition, the vector systems harboring various promoters with different strengths, conserved SD sequences, and multiple cloning sites will provide a comfortable method for cloning and gene expression, and consequently contribute to the metabolic engineering of C. glutamicum.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.230-235
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• 2016

This study was carried out to analyze the differences in enzyme activity and stability between the native Fe superoxide dismutase (FeSOD) and the 6xHis-tagged superoxide dismutase (6xHis-FeSOD) of Streptomyces subrutilus P5. The optimum pHs for both native FeSOD and 6xHis-FeSOD were 7, while the pH range of the activity was narrower for the 6xHis-FeSOD. The native FeSOD was stable at pH 4-9, but the 6xHis-FeSOD lost its stability at pH > 9. The temperatures of the optimum activities were same for both types of enzymes. However, the heat stability of the 6xHis-FeSOD was clearly decreased; even at $20^{\circ}C$ the enzyme lost the activity after 360 min. In contrast, the native FeSOD was stable after 720 min at below $40^{\circ}C$. $H_2O_2$ inhibition was occurred already at 0.5 mM for the 6xHis-tagged enzyme. Therefore, from the results that the 6xHis-FeSOD retained the enzyme activity at pH 6-7 and $20-40^{\circ}C$, it can be assumed that the protein structure became destabilized under different storage conditions and sensitive to the enzyme inhibitor.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2405-2409
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• 2011

The psychrophilic bacteria Psychromonas arctica survives at subzero temperatures by having adapted several protective mechanisms against freezing and oxidative stresses. Many reactive oxygen species are likely generated in P. arctica as a result of reduced metabolic turnover rates. A previous study identified the pasod gene for superoxide dismutase from P. arctica using a series of PCR amplifications. Here, upon cloning into a His-tag fused plasmid, the sod gene from P. arctica (pasod) was successfully expressed by IPTG induction. His-tagged PaSOD was subsequently purified by $Ni^{2+}$-NTA affinity chromatography. The purified PaSOD exhibited a higher SOD activity than that of Escherichia coli (EcSOD) at all temperatures. The difference in activity between PaSOD and EcSOD becomes even more significant at 4$^{\circ}C$, indicating that PaSOD plays a functional role in the cold adaptation of P. arctica in the Arctic.

• Journal of Life Science
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• v.26 no.1
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• pp.75-82
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• 2016

Pseudomonas rhodesiae KK1 has been reported to degrade polycyclic aromatic hydrocarbons (PAHs), such as anthracene, naphthalene, and phenanthrene, which are considered major environmental contaminants. Interestingly, antioxidant genes, including superoxide dismutase, are known to be expressed at different levels in response to environmental contaminants. This study was performed to identify the superoxide dismutase gene in strain KK1, which may be indirectly involved with degradation of PAHs, as well as to investigate the expression pattern of the superoxide dismutase gene in cells grown on different PAHs. Two types of superoxide dismutase genes responsible for the antioxidant defense mechanism, Mn-superoxide dismutase (sodA) and Fe-superoxide dismutase (sodB), were identified in P. rhodesiae KK1. The sodA gene in strain KK1 shared 95% similarity, based on 141 amino acids, with the Mn-sod of P. fluorescens Pf-5. The sodB strain, based on 135 amino acids, shared 99% similarity with the Fe-sod of P. fluorescens Pf-5. Southern hybridization using the sod gene fragment as a probe showed that at least two copies of superoxide dismutase genes exist in strain KK1. RT-PCR analysis revealed that the sodA and sodB genes were more strongly expressed in response to naphthalene and phenanthrene than to anthracene. Interestingly, sodA and sodB activities were revealed to be maintained in cells grown on all of the tested substrates, including glucose.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.1
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• pp.35-43
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• 2005

We describe here the complete nucleotide sequence and the exon-intron structure of the Cu,Zn superoxide dismutase (SOD1) gene of Paecilomyces tenuipes and Paecilomyces sp. The SOD1 gene of P. tenuipes spans 966 bp, and consisted of three introns and four exons coding for 154 amino acid residues. Three unambiguous introns in P. tenuipes separate exons of 13, 332, 97, and 20 bp, all exhibiting exon sizes identical to Cordyceps militaris SOD1 gene. The SOD1 gene of Paecilomyces sp. contains 946 bp and consisted of four introns and five exons coding for 154 amino acid residues. Five exons of Paecilomyces sp. SOD1 are composed of 13, 180, 152, 97, and 20 bp. Interestingly, this result showed that the total length of exons 2 (180 bp) and 3 (152 bp) of Paecilomyces sp. SOD1 is same to exon 2 length (332 bp) of C. militaris SOD1 and P. tenuipes SOD1. The deduced amino acid sequence of the P. tenuipes SOD1 showed $95\%$ identity to C. militaris SOD1 and $78\%$ to Paecilomyces sp. SOD1. Phylogenetic analysis confirmed that the C. militaris SOD1, P. tenuipes SOD1 and Paecilomyces sp. SOD1 are placed together within the ascomycetes group of fungal clade.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.94-99
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• 2004

The activities of enzymes that act on oxygen derivatives in Rhodobacter sphaeroides D-230 were investigated under various culture conditions. Intracellular SOD activity from the cells grown in aerobic or anaerobic culture conditions was highest at pH 7.0 and pH 8.0, respectively. On the other hand, extracellular SOD activity was highest at pH 6.0. Catalase activity was highest at neutral pH in both cases. Growth of R. sphaeroides D-230 in aerobic or anaerobic culture conditions was inhibited by methyl viologen. As R. sphaeroides D-230 was cul-tured aerobically, SOD activity was increased about 2-fold by addition of iron ion. But $Mn^+2$ had little effect on the SOD activity of R. sphaeroides D-230 grown in aerobically. NaCN, the inhibitor of Cu$.$Zn-SOD, did not inhibit SOD activity. But, $NaN_3$, the inhibitor of Mn-SOD, inhibited SOD activity in anaerobic cultures con-dition. Therefore, R. sphaeroides D-230 produce Mn-SOD in anaerobic condition, although Fe-Sod is produced in aerobic condition. The activity of catalase was induced by methyl viologen, however, extremely inhibited by NaCN and $NaN_3$.

• Journal of the Korean Society of Tobacco Science
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• v.15 no.1
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• pp.3-14
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• 1993

Oxidants in environment or cigarette smoke are known to be implicated in the oxidative damages of pulmonary system. Such cellular damages are prevented by the presence of adequate levels of antioxidants in the tissue. In the present study, we investigated the influences of smoking duration and concentration of smoke on lung antioxidant defense in rats. Subchronic exposure of rats to smoke generated from 6 cigarettes per day for 90 days caused the activities of catalase and superoxide dismutase (SOD) to increase. However, glutathione peroxidase (GP-Xase) was not significantly changed. Total sulfhydryl compounds (Total-SH) in the lung homogenates from the rats inhaled with cigarette smoke for 15 days was decreased by 44% , thereafter it was returned to the level of normal rats. On the contrary, when rats were daily exposed to a different concentration of smoke generated from 1 to 20 cigarettes per day for 15 days, the activity of catalase was increased gradually with dose, but total SOD activity was increased only in the rats of low dose groups less than 5 cigarettes. Three types of SOD (one Cu, Zn-SOD with pI 4.9, and two Zn-SOD with pI 4.7 and 7.9)were detected in the lung homogenates and Zn-SOD with pI 4.7 was the major and cigarette-smoke inducible form. These results indicate that the protection of lung against oxidants from cigarette smoke seems to be accomplished by the induction of catalase and SOD, especially a cyanide resistant Zn-SOD with pI 4.f, following the consumption of antioxidants such as GSH in the beginning of inhalation period.

• Journal of Life Science
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• v.20 no.4
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• pp.555-560
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• 2010

The objective of this study was to investigate levels of serum creatinine, CuSOD and MnSOD protein expression in the kidney after renal ischemic reperfusion with pre-exercise using heat shock protein 70.1 in knock-out mice (KO). The C57/BL6 strain (Wild type: WT) and KO were divided into 4 groups as follows: Sham control group (Sham), pre-exercise group (Ex), pre-exercise +ischemia group (Ex+IR), and ischemia group (IR). CuSOD and MnSOD expression were significantly decreased (p<0.01, p<0.05) and blood creatinine concentration was significantly increased (p<0.01) in the IR group of KO. In contrast, CuSOD and MnSOD expression in the Ex+IR group of KO were higher than the IR group, while creatinine concentration was significantly lower. These results suggest that Hsp70 is directly correlated to renal ischemic reperfusion injury. Pre-exercise in renal ischemia might prevent or inhibit positive oxidative stress inhibitory effects by increasing anti-oxidative enzymes (CuSOD, MnSOD) within the kidney and improve to prevent renal function. Thus, pre-exercise may have a protective role against renal injury after renal ischemia.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.173-182
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• 2001

The present study was carried out to examine the effect of superoxide dismutase (SOD) on in vitro maturation (IVM) of porcine follicular oocytes and oxygen concentration with SOD on in vitro development (IVD) of porcine IVM/IVF embryos. The results were summarized as follows : 1. The rates of nuclear maturation, penetrated oocytes, polyspermic oocytes and mean numbers of the penetrated sperm were not different in the NCSU-23 maturation media with 0, 100, 500 and 1,000 units/ml SOD. However. the pronucleus formation rates were significantly lower in oocytes matured with addition groups than those of no addition groups of SOD (P>0.05). 2. The rates of blastocyst formation and total cell numbers of blastocyst at day 7 after in vitro fertilization were significantly lower in addition groups than those of the no addition groups of SOD (P>0.05). 3. The rates of blastocyst formation at day 7 after in vitro fertilization were higher in the NCSU-23 culture medium with 100 units/ml SOD than in those cultured with 0, 500 and 1,000 units/ml SOD under the 5% and 20% $O_2$concentrations. However, no differences was found in the total cell numbers of blastocyst among the treatments. In conclusion, these results suggested that the addition of SOD was not adequate for porcine oocyte maturation and further development, also the rates of blastocyst formation and total cell numbers of blastocyst at day 7 of porcine IVM/IVF embryos were not different in the NCSU-23 culture medium under the 5% and 20% $O_2$concentrations.