• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.579-590
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• 2001

Background : The aging process may be induced, at least in part, by reactive oxygen species(ROS). It has been thought that the lung could be a good source of ROS because it has a high oxygen tension. In the present study, we invetigated the inducibility of the first and last lines against oxidative stress, superoxide dismutases(CujZn-SOD and Mn-SOD) as a scavenger of ${O_2}^-\;{\cdot}$ and metallothionein(MT) as a scavenger of $OH{\cdot}$, respectively, in mouse lungs with age. Methods : Oxidative stress was induced by paraquat, an intracellular superoxide generator, at 1, 4, 8, and 12 months of age and then SODs and MT mRNAs were determined by RT-PCR method. Results : The steady-state level of Mn-SOD mRNA increased from 1 to 8 months but decreased thereafter. However, Mn-SOD mRNA was not induced by paraquat after 1 month. On the other hand, there was no change in the steady-state level of Cu/Zn-SOD mRNA, which decreased abruptly at 12 months of age. Additionally, Cu/Zn-SOD mRNA was not induced by paraquat at any age. There was no change in the steady-state level of MT mRNA with age whereas its inducibility by paraquat was intact at all ages. Conclusion : These results indicate that lack of induction of SODs with age may be one of the causative factors in the aging process while induction of MT may play an important role in the defense against oxidative stress. It is therefore implicated that the tissue antioxidant/prooxidant balance could be one of determinants of mean life span.

• Journal of Microbiology
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• v.39 no.3
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• pp.232-235
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• 2001

Electrophoretic resolution of superoxide dismutase (SOD) from the highly UV-resistant bacteria, Deinococcus species revealed multiple forms of superoxide dismutases (SODs) in D. radiodurans, D. grandis, and D. proteolyticus, as judged from electrophoretic properties and metal cofactors. A single SOD occurred in both D. radiophilus and D. radiopugnans. Deinococcal SODs were either MnSOD, FeSOD or cambialistic Mn/FeSOD. The unique SOD profile of each mesophilic Deinococcus species, multiplicity and metal cofactors would be valuable in identifying Deinococcus species.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.862-868
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• 2012

Based on the recently derived general expression for the rates of diffusion-controlled reactions, we calculate the rates of dismutation of the superoxide anion radical catalyzed by Cu/Zn superoxide dismutases (SOD). This is the first attempt to calculate the absolute rates of diffusion-controlled enzyme reactions based on the atomiclevel molecular dynamics simulations. All solvent molecules are included explicitly and the effects of the structural flexibility of enzyme, especially those of side chain motions near the active site, are included in the present calculation. In addition, the actual mobility of the substrate molecule is taken into account, which may change as the molecule approaches the active site of enzyme from the bulk solution. The absolute value of the rate constant for the wild type SOD reaction obtained from MD simulation is shown to be in good agreement with the experimental value. The calculated reactivity of a mutant SOD is also in agreement with the experimental result.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.316.2-316
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• 1995

No Abstract, See Full Text

• Proceedings of the Microbiological Society of Korea Conference
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• 2004.05a
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• pp.47-50
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• 2004

The defenses against free radical damage include specialized repair enzymes that correct oxidative damages in DNA, and detoxification systems such as superoxide dismutases. These defenses may be coordinated genetically as global responses. We hypothesized that the expression of the SOD and the DNA repair genes would inhibit DNA damage under oxidative stress. Therefore, the protection of E. coli mutants deficient in SOD and DNA repair genes $(sod^-\;xth^-\;and\;nfo^-)$ was demonstrated by transforming the mutant strain with a plasmid pYK9 which encoded Photobacterium leiognathi CuZnSOD and human AP endonuclease. The results show that survival rates were increased in $sod^+\;xth^-\;nfo^+$ cells compared to $sod^-\;xth^-\;ap^+,\;sod^-\;xth^-\;ap^-,\;and\;sod^+\;xth^-\;ap^-$ cells under oxidative stress generated from 0.1 mM Paraquat or 3 mM $H_2O_2$. The data suggested that, at least, SOD and DNA repair enzymes may have collaborate protection and repair of the damaged DNA. Additionally, both enzymes are required for protection against free radicals.

• 대한생식의학회:학술대회논문집
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• 1996.11a
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• pp.35.2-36
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• 1996

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.270-275
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• 2005

Superoxide dismutases (SOD) are metalloenzymes that convert $O_2^-\;to\;H_2O_2$. Rehmannia glutinosa is highly tolerant to paraquat-induced oxidative stress. The primary objective of this study was to characterize regulation of SOD gene expression in R. glutinosa in response to oxidative stresses and hormones. A full-length putative SOD clone (RgCu-ZnSOD1) was isolated from the leaf cDNA library of R. glutinosa using an expressed sequence tag clone as a probe. RgCu-ZnSOD1 cDNA is 777 bp in length and contains an open reading frame for a polypeptide consisted of 152 amino acid residues. The deduced amino acid sequence of the clone shows highest sequence similarity to the cytosolic Cu-ZnSODs. The two to three major bands with several minor ones on the Southern blots indicate that RgCu-ZnSOD1 is a member of a small multi-gene family. RgCuZnSOD1 mRNA was constitutively expressed in the leaf, flower and root. The expression of RgCu-ZnSOD1 mRNA was increased about 20% by wounding and paraquat, but decreased over 50% by ethylene and $GA_3$. This result indicates that the RgCu-ZnSOD1 expression is regulated differentially by different stresses and phytohormones at the transcription level. The RgCu-ZnSOD1 sequence and information on its regulation will be useful in investigating the role of SOD in the paraquat tolerance of R. glutinosa.

• International Journal of Industrial Entomology and Biomaterials
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• v.13 no.1
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• pp.23-30
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• 2006

BmCu/Zn SOD was isolated from early embryo of Bombyx mori using microarray analysis. The BmCu/Zn SOD gene was observed during the early embryonic stage with the strongest signal found at the unfertilizaion, fertilization and blastoderm stages. The BmCu/Zn SOD gene encodes a protein of 154 amino acids with a calculated Mr of 15 kDa. The deduced amino acid sequence of BmCu/Zn SOD indicated that the residues that form on the Cu/Zn binding site are conserved and that the sequence is a 60% identity to that of M. domestica. In a phylogenetic tree, Bm SOD was also close to Drosophila SODs rather than other insect SODs. The BmCu/Zn SOD gene exists as a single copy in the genome. Transcripts of BmCu/Zn SOD cDNA were identified by northern blot analysis. The expression of the BmCu/Zn SOD gene was observed weakly in most of larvae, pre-pupae, pupae and adult tissues. Also, the BmCu/Zn SOD gene was observed in early embryonic stage. Although the roles of SODs remains to be further elucidated, the high expression of BmCu/Zn SOD gene at before 24 h post fertilization suggests that this gene is of general importance during early embryogenesis in the Bombyx mod.

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.26-26
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• 1998

Superoxide dismutases are metalloenzymes catalyzing the dimutation of superoxide anion radical to hydrogen peroxide and molecular oxygen. Examples of enzymes containing Cu, Mn and Fe as the redox-active metal have been characterized. Recently, an SOD containing one Ni atom per subunit was reported.(omitted)

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.222-222
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• 2004

Superoxide dismutases are key antioxidant enzymes in metabolism of reactive oxygen species. Three different isoforms of SOD exist in mammals. The extracellular SOD (EC-SOD) is the most recently discovered SOD family member. This isoform is a copper- and zinc-containing enzyme like Cu/Zn-SOD and a homotetrameric glycoprotein with a molecular weight of about 165 kDa in mouse. (omitted)