• Title/Summary/Keyword: Superoxide dismutases

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Role of Inducibility of Superoxide Dismutases and Metallothionein of Mouse Lungs by Paraquat in Aging (Paraquat에 의한 생쥐 폐의 Superoxide Dismutases와 Metallothionein의 유도능과 노화와의 관계)

  • Lee, Tae-Bum;Park, Yoo-Hwan;Choi, Cheol-Hee
    • 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.

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Calculation of the Absolute Rate of Human Cu/Zn Superoxide Dismutases from Atomic-Level Molecular Dynamics Simulations

  • Lee, Jin-Uk;Lee, Woo-Jin;Park, Hwang-Seo;Lee, Sang-Youb
    • 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.

  • https://doi.org/10.5012/bkcs.2012.33.3.862 인용 PDF KSCI

Superoxide Dismutase Profiles in the Mesophilic Deinococcus Species

  • Yun, Young-Sun;Lee, Young-Nam
    • 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.

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