• Title/Summary/Keyword: Zinc-superoxide

Search Result 79, Processing Time 0.192 seconds

Expression and Characterization of Recombinant Human Cu,Zn-Superoxide Dismutase in Escherichia coli

  • Kang, Jung-Hoon;Choi, Bong-Jin;Kim, Sung-Moon
    • BMB Reports
    • /
    • v.30 no.1
    • /
    • pp.60-65
    • /
    • 1997
  • Expression of human Cu.Zn-superoxide dismutase (SOD) with activity comparable to human erythrocyte enzyme was achieved in E. coli B21(DE3) by using the pET-17b expression vector containing a T7 promoter. Recombinant human SOD was found in the cytosol of disrupted bacterial cells and represented > 25% of the total bacterial proteins. The protein produced by the E. coli cells was purified using a combination of ammonium sulfate precipitation, Sephacryl S-100 gel filtration and DEAE-Sephacel ion exchange chromatography. The recombinant Cu,Zn-SOD and human erythrocyte enzyme were compared using dismutation activity, SDS-PAGE and immunoblotting analysis. The mass of the subunits was determined to be 15,809 by using a electrospray mass spectrometer. The copper specific chelator. diethyldithiocarbamate (DOC) reacted with the recombinant Cu,Zn-SOD. At $50{\mu}M$ and $100{\mu}M$ concentrations of DOC, the dismutation activity was not inhibited for one hour but gradually reduced after one hour. This result suggests that the reaction of DOC with the enzyme occurred in two distinct phases (phase I and phase II). During phase I of this reaction, one DOC reacted with the copper center, with retention of the dismutation activity while the second DOC displaced the copper, with a loss of activity in phase II.

  • PDF

Hydroxyl Radical-Generating Function of Horseradish Cu,Zn-Superoxide Dismutase

  • Eum, Won-Sik;Kwon, Oh-Bin;Kang, Jung Hoon
    • BMB Reports
    • /
    • v.31 no.5
    • /
    • pp.492-497
    • /
    • 1998
  • Cu,Zn-superoxide dismutase (SOD) was purified from horseradish by using Mono Q and Superose 12 FPLC column chromatography. The native molecular mass of the purified enzyme was approximately 33 kDa, as determined by gel filtration. The subunit molecular weight, as estimated by SDS-PAGE, was 16 kDa. These results indicated that the native enzyme is a homodimer. We investigated the free radical-generating function of horseradish Cu,Zn-SOD by using a chromogen, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate) (ABTS) which reacts with ${\cdot}OH$ radicals to form $ABTS^{+{\cdot}}$ The formation of $ABTS^{+{\cdot}}$ was required for both active Cu, Zn-SOD and $H_2O_2$. The optimal pH for the free radical-generating activity of this enzyme was 6.0-8.0, and it retained about $40^{\circ}C$ of its maximum activity when exposed at $40^{\circ}C$ for 15 min. A neutral scavenger, ethanol, inhibited the $ABTS^{+{\cdot}}$ formation by horseradish Cu, Zn-SOD more effectively than that by the mammalian enzyme. These results suggest that the active channel of horseradish enzyme is slightly larger than that of the mammalian enzyme.

  • PDF

Molecular Characterization and Expression of CuZn-superoxide Dismutase (PSOD1) from Populus alba${\times}$Populus glandulosa

  • Lee Jun-Won;In Jun-Gyo;Lee Bum-Soo;Choi Yong-Eui;Kim Jin-Ju;Yang Deok-Chun
    • Plant Resources
    • /
    • v.8 no.1
    • /
    • pp.52-59
    • /
    • 2005
  • A cDNA, PSOD1, encoding cytosolic copper/zinc superoxide dismutase (CuZn-SOD) was cloned and characterized from a full length cDNA library prepared from Populus alba${\times}$Populus glandulosa cultured in vitro. A PSOD1, is 725 nucleotides long and has an open reading frame of 459 bp with 152 amino acid residues (pI 5.43). The deduced amino acid sequence of PSOD1 perfect matched to the previously reported CuZn-SOD (CAC33845.1). Consensus amino acid residues (His-45, -47, -62, -70, -79, -119) were involved in Cu-, Cu/Zn-, and Zn- binding ligands. The deduced amino acid sequence of PSOD1 exhibited the high level of similarity from 100 to $85\%$ among previously registered SOD genes. The expression of PSOD1 in poplar increased at the 1 mM $H_{2}O_2$ and drought stress during 30 min and 60 min, but the ozone treated poplar increased at 30 min in the early time and then decreased at 60 min.

  • PDF

Effect of Myricetin on mRNA Expression of Different Antioxidant Enzymes in B16F10 Murine Melanoma Cells (B16F10 Murine Melanoma Cell에서 Myricetin이 항산화효소의 m-RNA 발현에 미치는 영향)

  • Yu Ji Sun;Kim An Keun
    • YAKHAK HOEJI
    • /
    • v.49 no.1
    • /
    • pp.86-91
    • /
    • 2005
  • Flavonoids are class of polyphenolic compounds widely distributed in the plant kingdom, which display a variety of biological activities, including antiviral, antithrombotic, antiinflammatory, antihistaminic, antioxidant and free-radica 1 scavenging abilities. The antioxidant enzyme (AOE) system plays an important role in the defense against oxidative stress insults. To determine whether flavonoid, myricetin can exert antioxidative effects not only directly by modulating the AOE system but also scavenging free radical, we investigated the influence of the flavonoid myricetin on cell viability, different antioxidant enzyme activities, ROS level and the expression of different antioxidant emzyme in B16F10 murine melanoma cells. Myricetin in a concentration range from 6.25 to $50\;{\mu}M$ decreased superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities, but catalase (CAT) activity was increased. In the myricetin-treated group, ROS levels were decreased dose-dependently. Antioxidant enzyme expression was measured by RT-PCR. Myricetin treatment of B16F10 cells increased catalase expression. Expression levels of copper zinc superoxide dismutase (CuZn SOD) were not affected by exposure of myricetin. Manganese superoxide dismutase (Mn SOD) and GPx expression levels decreased slightly after myricetin treatment. In conclusion, the antioxidant capacity of myricetin was due to CAT and free-radical scavenging.

Purification and Characterization of Iron-Containing Superoxide Dismutase from Lentinus edodes

  • Park, Sang-Shin;Hwang, Soo-Myung
    • Journal of Microbiology and Biotechnology
    • /
    • v.9 no.6
    • /
    • pp.854-860
    • /
    • 1999
  • Superoxide dismutase (SOD) was purified to homogeneity from fruiting bodies of edible mushroom, Lentinus edodes, by ammonium sulfate precipitation, diethylaminoethyl (DEAE)-Sepharose FF ion-exchange chromatography, Sephacryl S-200 gel filtration chromatography, and preparative PAGE. The molecular weight of the purified enzyme was estimated to be approximately 54 kDa by gel filtration chromatography, and the enzyme was shown to be consisted of two identical subunits of molecular weight 27 kDa by SDS-PAGE. The isoelectric point of the enzyme was 4.9 as determined by isoelectric focusing. The enzyme had optimal pH and temperature of pH 8.0 and $20^{\circ}C$, respectively. The activity of the enzyme was inhibited by hydrogen peroxide, but inhibited less by cyanide and azide. The native enzyme was found to contain 0.89g-atom of iron, 0.75g-atom of zinc, and 0.46g-atom of copper per mol of enzyme. Analysis of amino acids composition revealed that the SOD from L. edodes contained a relatively large amount of glutamic acid/glutamine, proline, cysteine, isoleucine, and leucine, but only a small amount of aspartic acid/asparagine, tyrosine, and tryptophan when compared to the other iron-containing SODs.

  • PDF

Expression of Superoxide Dismutase Isoforms in Inflamed Gingiva (염증성 치은에서 superoxide dismutase isoform의 발현에 대한 연구)

  • Na, Hei-Jin;Kim, Ok-Su;Park, Byung-Ju
    • Journal of Periodontal and Implant Science
    • /
    • v.36 no.1
    • /
    • pp.97-112
    • /
    • 2006
  • 유리 라디칼과 활성 산소종, 산화방지제 간의 불균형이 염증성 구강내 질환의 발생과 진행에 있어 중요한 역할을 한다는 주장이 제기되었고 최근에는 만성 염증성 치주질환에서도 산화에 의한 소실이 관찰되었다. 다양한 내적인 항산화 방어 기전 중 superoxide dismutase 가 $O_2$$H_2O_2$로 효과적으로 전환시킴으로써 활성산소종에 대한 일차적인 방어를 맡고 있다. 현재까지 인간에서 발견된 superoxide dismutase 는 cytoplasmic copper-zinc SOD와 mitochondrial manganase SOD, extracellular SOD의 3가지 아형이다. 이번 연구는 만성 치주질환을 가전 환자의 치주조직에서 효소 항산화제인 SOD의 발현정도를 알아봄으로써 질환조직 내의 산화자극 정도를 평가해 보고자하였다. 전남대학교 치주과에 내원한 33명의 만성 치주질환자와 20명 의 임상적으로 건강한 대상으로부터 조직을 얻어 Cu/Zn-SOD와 Mn-SOD, EC-SOD를 이용한 면역조직화학 염색을 시행하였다. 임상적 소견과 조직학적 소견이 일치하지 않아 조직학적 소견을 기준으로 건강한 조직, 경도, 중등도, 중도 치주질환 조직으로 그룹을 나누고 완전한 상피와 결합조직을 가진 27개의 표본에 대한 분석을 시행하였다. 치주질환 조직에서 건강한 조직에 비해 Cu/Zn-SOD가 상피의 기저층과 상피에 근접한 결합조직에서 발현되고 Mn-SOD는 염증이 증가함에 따라 크게 상피의 과립증과 각화층, 그리고 상피에 근접한 결합조직에서 발현됨으로써 활성산소종이 치주조직 파괴에 관여한다는 것을 알 수 있었다. 세 아형 모두 혈관주위에서 발현되었고 특히 EC-SOD는 작은 모세혈관주위에서만 발현되었으나 염증에 의해 혈관벽이 두꺼워지고 혈관 수가 증가한 곳에서 뚜렷하게 염색되었다. 이번 연구는 염증성 치주조직내 증가된 SOD의 활성이 치주질환자의 산화자극 정도와 관련되어 있음을 시사하였다.

The Effect of Zinc Levels on Free Radical Generating System in Cadmium Treated Rats (아연수준이 카드뮴을 투여한 흰쥐의 항산화 효소게에 미치는 영향)

  • 조수열;김명주;이미경
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.23 no.5
    • /
    • pp.725-730
    • /
    • 1994
  • This study was conducted to investigate the effect of dietary zinc (Zn) and/or cadmium (Cd) on hepatic microsomal and cytosol enzyme activities. Male Spraque-Dawley rats (110$\pm$10g ) received zinc (0, 30 and 300 ppm/) and Cd-treated groups were administered oral intubation with Cd chloride (5.0mg/kg of body weight 0 at the same time once a week. The effect of Cd on the activity of hepatic cytochromep-450 , xanthine oxidase(X. O) and superoxide dismutase (SOd) was studied in rats. Cd oral intubation resulted in a decrease in cytochrome P-450 content and SOD activity whereas a significant increase in the X.O. activity was observed was observed . Intake of excessive Zn led to an increased activity of microsomal alcohol dehydrogenase (ADH) , whereas Zn deficiency group led to a decreased group. The mechanism by which Zn induces the decreasing of Cd toxicity in rats, seems to rely on the protection of the enzyme systems P-450, ADH, aldehyde dehydrogenase (ALDH) and X.O. in the liver, possibly by forming non-toxic Cd metallothionein. These results indicate that Zn and Cd regulation might occur via inhibitory protein component of the $H_2O$$_2$ -generator system.

  • PDF

Oxidative stress and non-specific immune responses in juvenile black sea bream, Acanthopagrus schlegelii, exposed to waterborne zinc

  • Kim, Jun-Hwan;Park, Hee-Ju;Kim, Kyeong-Wook;Kang, Ju-Chan
    • Fisheries and Aquatic Sciences
    • /
    • v.20 no.6
    • /
    • pp.11.1-11.8
    • /
    • 2017
  • Juvenile black sea bream, Acanthopagrus schlegelii, were exposed to waterborne zinc (Zn) at concentrations of 0, 200, and $400{\mu}g/L$, at temperatures of 18 or $26^{\circ}C$ for 4 weeks. Superoxide dismutase (SOD) activities in the liver and gill of A. schlegelii significantly increased following exposure to waterborne Zn. Significant reduction in glutathione S-transferase (GST) activity in the liver and gill was observed following exposure to waterborne Zn. Glutathione (GSH) concentrations in the liver and gill also significantly decreased following exposure to waterborne Zn. Phagocytosis and lysozyme in the plasma and kidney were significantly increased following exposure to waterborne Zn. High water temperature increased alterations in the antioxidant and immune responses. The results of the present study suggest that waterborne Zn induced significant alterations in oxidative stress, increased immune responses and high temperature that trigger Zn toxicity.