• 미생물학회지
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• 제51권2호
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• pp.108-114
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• 2015

본 연구에서는 Streptomyces subrutilus P5의 생장과 세포내 외 철 함유 superoxide dismutase 활성을 비교 분석하여 철함유 superoxide dismutase의 분비 시점을 확인하고 분자 수준에서 이 효소의 분비에 관여하는 유전정보를 확인하고자 하였다. Streptomyces subrutilus P5의 균체 생장은 건체 중량을 측정하여 결정하였다. Glucose는 log phase에서 급격히 소모되어 24시간 후에 이르러 완전히 고갈되었다. 세포내의 철 함유 superoxide dismutase는 배양 후 3시간에 나타나며 세포외 철 함유 superoxide dismutase는 배양 후 7.5시간부터 나타난다. 따라서 superoxide dismutase는 용균에 의해서가 아니라 능동적인 분비기작에 의해서 세포 외로 분비된 것으로 추측할 수 있다. Streptomyces subrutilus P5의 sodF에는 signal peptide 유전정보가 존재하지 않았다. 그러나 sodF의 상류지역에서 다른 세균의 type III 분비단백질 유전자와 유사한 type III 분비상자가 발견되었다. Streptomyces 균주에서 type III 분비단백질이 존재할 가능성이 있음을 처음으로 제시하였다.

• 미생물학회지
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• 제53권2호
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• pp.118-122
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• 2017

납, 아연, 카드뮴에 의한 미생물 생장 저해를 변형된 Tris minimal medium을 사용하여 측정하였다. Escherichia coli 균주에 대한 독성의 세기는 아연 > 카드뮴 > 납 순으로 나타났고 Streptomyces coelicolor A3(2)의 철 함유 superoxide dismutase 2를 과발현하는 E. coli 균주는 중금속 저항성이 증가되었음을 알 수 있었다.

• KSBB Journal
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• 제18권6호
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• pp.517-521
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• 2003

본 연구에서는 절대적 호기성인 Vitreoscilla가 지닌 FeSOD의 특성을 밝히고자 paraquat와 iron을 사용하여 실험하였다. Vitreoscilla에서 FeSOD의 활성도는 초산화 음이온을 생성하는 paraquat에 대해 커다란 영향 없이 일정하게 발현되었다. 이 결과는 Vitreoscilla는 호기적인 물질대사 동안 생성되어지는 초산화 음이온에 대해 방어할 수 있을 만큼 충분한 FeSOD를 평상시 지니고 있음을 의미한다. 또한 다른 요소에 의한 FeSOD의 발현 가능성이 고려되어졌다. 보조 인자인 Fe 를 처리한 결과 활성도가 증가됨을 알 수 있었다. 이는 CN-resistant respiration을 증가시키는 초산화 음이온에 대한 조절 기작과는 달리 apoenzyme 상태가 보조 인자인 금속 이온 (Fe)에 의해 holoenzyme 상태로 전환되었음을 의미한다. PQ와 Fe를 함께 처리하였을 경우, FeSOD의 증가는 PQ에 의해서 생성된 초산화 음이온에 의해 apo 상태에서 hole 상태로 FeSOD의 활성이 증진되는 synergism effect로 설명되어진다. 결론적으로 metalloenzyme인 SOD의 경우는 이런 전환이 활성 속도를 제한하거나 조절할 수도 있는 posttranslational 수준의 조절 기작이 존재함을 알 수 있었다.

• 한국식품영양과학회지
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• 제23권6호
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• pp.1020-1026
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• 1994

비교적 연구가 미비한 Fe-SOD의 효소화학적 특성 및 그 생리적 기능을 검토하기 위해 여러 종의 세균을 대상으로하여 Fe-SOD의 고생산균주를 screening하였다. 그 결과 Fe-SOD를 대량 세포내에 생성하는 Pseudomonas polycolor를 선발하여, 이 균주의 효소생산 최적 배양조건을 설정하였다. 본 균주가 생산하는 효소는 특이적인 저해제의 작용양식에 의해 Fe을 cofactor로 요구하는 Fe-SOD임이 밝혀졌다. SOD 생성을 위한 최적배지조성은 glycerin 3%, polypeptone 1%, meat extract 0.5%, KCI 0.2%이었고, 최적 초발 pH는 9.0이었으며, 이 조건에서 500ml용 shaking flask에 배지 100ml를 넣어 15시간 전 후 배양했을 경우가 효소생산량은 최대가 되었다.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.854-860
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• 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.

• Molecules and Cells
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• 제23권3호
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• pp.370-378
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• 2007

A superoxide dismutase was purified 62-fold in seven steps to homogeneity from Methylobacillus sp. strain SK1, an obligate methanol-oxidizing bacterium, with a yield of 9.6%. The final specific activity was 4,831 units per milligram protein as determined by an assay based on a 50% decrease in the rate of cytochrome c reduction. The molecular weight of the native enzyme was estimated to be 44,000. Sodium dodecyl sulfate gel electrophoresis revealed two identical subunits of molecular weight 23,100. The isoelectric point of the purified enzyme was found to be 4.4. Maximum activity of the enzyme was measured at pH 8. The enzyme was stable at pH range from 6 to 8 and at high temperature. The enzyme showed an absorption peak at 280 nm with a shoulder at 292 nm. Hydrogen peroxide and sodium azide, but not sodium cyanide, was found to inhibit the purified enzyme. The enzyme activity in cell-free extracts prepared from cells grown in manganese-rich medium, however, was not inhibited by hydrogen peroxide but inhibited by sodium azide. The activity in cell extracts from cells grown in iron-rich medium was found to be highly sensitive to hydrogen peroxide and sodium azide. One mol of native enzyme was found to contain 1.1 g-atom of iron and 0.7 g-atom of manganese. The N-terminal amino acid sequence of the purified enzyme was Ala-Tyr-Thr-Leu-Pro-Pro-Leu-Asn-Tyr-Ala-Tyr. The superoxide dismutase of Methylobacillus sp. strain SK1 was found to have antigenic sites identical to those of Methylobacillus glycogenes enzyme. The enzyme, however, shared no antigenic sites with Mycobacterium sp. strain JC1, Methylovorus sp. strain SS1, Methylobacterium sp. strain SY1, and Methylosinus trichosproium enzymes.

• Journal of Microbiology and Biotechnology
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• 제3권3호
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• pp.188-193
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• 1993

Superoxide dismutase (SOD) was purified from Pseudomonas polycolor to an electrophoretically homogeneous state and partially characterized. SOD was purified by ammonium sulfate fractionation, column chromatography on DEAE-Sephadex A-50, phenyl-Toyopearl 650 M, and gel filtration on Sephadex G-100. The molecular weight and subunit molecular weight of the purified enzyme were estimated to be 40, 000 and 20, 000, respectively. The purified enzyme remained stable at pH 9.0~11.0, $25^{\circ}C$ for 40 hr, but rapidly became inactive below 9.0. SOD was stable up to $45^{\circ}C$ at pH 9.0 with about 80% relative activity, but rapidly became inactive at temperature above that. The enzyme was insensitive to cyanide and fluoride, and sensitive to hydrogen peroxide and azide. The results suggest that the enzyme be an iron-containing SOD.

• Journal of Microbiology
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• 제40권2호
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• pp.151-155
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• 2002

A Superoxide Dismutase (SOD) gene from the obligate intracellular bacterium Orientia tsutsugamushi has been cloned by using the polymerase chain reaction with degenerate oligonucleotide primers corresponding to conserved regions of known SODs. Nucleotide sequencing revealed that the predicted amino acid sequence was significantly more homologous to known iron-containing SODs (FeSOD) than to manganese-containing SODs (MnSOD). Conserved regions in bacterial FeSOD could also be seen. Isolation of the oriential SOD gene may provide an opportunity to examine its role in the intracellular survival of this bacterium.

• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.700-706
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• 2000

Iron- and zinc-containing superoxide dismutase (FeZnSOD) and nickel-containing superoxide dismutase (NiSOD) are cytoplamic enzymes in Streptomyces griseus. The sodF gene coding for FeZnSOD was cloned from genomic Southern hybridization analysis with a 0.5-kb DNA probe, which was PCR-amplified with facing primers corresponding to the N-terminal amino acid of the purified FeZnSOD of S. griseus and a C-terminal region which is conserved among bacterial FeSODs and MnSODs. The sodF open reading frame (ORF) was comprised of 213 amino acid (22,430 Da), and the deduced sequence of the protein was highly homologous (86% identity) to that of FeZnSOD of Streptomyces coelicolor. The FeZnSOD expression of exponentially growing S. griseus cell was approximately doubled as the cell growth reached the early stationary phase. The growth-associated expression of FeZnSOD was mainly controlled at the transcriptional level, and the regulation was exerted through the 110 bp regulatory DNA upstream from the ATG initiation codon of the sodF gene.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 2003년도 International Symposium of Silkworm/Insect Biotechnology and Annual Meeting of Korea Society of Sericultural Science
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• pp.66-70
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• 2003

The first line of antioxidant defense against reactive oxygen species includes the enzymatic activity of the superoxide dismutase (SOD) that catalyzes the disproportionation of superoxide to hydrogen peroxide and water. The SOD mainly removes highly toxic $O_2$$^{[-10]}$ and also prevents $O_2$$^{[-10]}$ mediated reduction of iron and subsequent OH$^{[-10]}$ generation. Along with an interest in SOD as a first line of defense against damage mediated by the superoxide anion, the SOD1 enzyme has been subjected to investigation in the molecular and cellular level. (omitted)