• 원예과학기술지
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• 제29권5호
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• pp.413-419
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• 2011

국내 자생 수생식물인 노랑꽃창포와 창포를 수질 내 카드뮴(Cd) 제거용 식물재료로 이용하고자 Cd 축적과 내성을 조사하였다. Cd 농도에 따른 치사율을 근거로 Cd에 대한 반수치사량($LD_{50}$)을 계산한 결과, 노랑꽃창포는 $78.5{\mu}M$, 창포는 $47.6{\mu}M$로 나타났다. Cd 스트레스에 대해 노랑꽃창포에서는 POD와 SOD, 창포에서는 CAT와 SOD, 폴리페놀이 활성화되었다. 노랑꽃창포에서는 폴리페놀이 측정되지 않았다. 노랑꽃창포와 창포 모두 Cd 처리 농도가 증가하고 기간이 길어질수록 식물체 내 Cd 축적량이 증가하였고, 두 종 모두 지상부보다는 지하부 축적량이 현저하게 많았다. 지상부에 축적된 Cd 함량은 노랑꽃창포 $548.1mg{\cdot}kg^{-1}$(지하부 축적 대비 82.1%) 창포 $121.4mg{\cdot}kg^{-1}$(지하부 축적 대비 13.7%)로 두 종 모두 Cd 고축적식물로 확인되었으며, 특히 노랑꽃 창포가 Cd 축적능력과 내성이 우수하였다.

• 대한임상검사과학회지
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• 제48권1호
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• pp.1-7
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• 2016

본 연구는 배양 NIH3T3 섬유모세포를 재료로 독성물질인 염화카드뮴($CdCl_2$)의 세포독성과 이에 대한 애기똥풀(Chelidonium majus, CM) 추출물의 방어효과를 조사하기 위하여 세포생존율(cell viability)을 비롯한 $CdCl_2$에 대한 BHT의 영향 및 DPPH-자유라디칼 소거능, superoxide anion-radical scavenging activity (SSA), lactate dehydrogenase (LDH) 활성과 같은 항산화 효과를 분석하였다. 그 결과 $CdCl_2$는 농도 의존적으로 배양 NIH3T3 섬유모세포의 생존율을 유의하게 감소하였으며, $XTT_{50}$값이 38.7uM로 나타나 Borenfreund와 Puerner의 독성판정기준에 따라 고독성(highly-toxic)인 것으로 나타났다. 또한, 항산화제인 BHT는 $CdCl_2$의 독성으로 인하여 심하게 손상된 세포생존율을 유의하게 증가시켰다. 한편, $CdCl_2$의 세포독성에 대한 CM 추출물의 방어효과에서, CM 추출물은 $CdCl_2$에 의하여 감소된 세포생존율을 유의하게 증가시켰으며, 또한 DPPH-자유라디칼 소거능을 비롯한 SSA 및 LDH 활성 억제와 같은 항산화능을 나타냈다. 이상의 결과에서 $CdCl_2$의 독성에 산화적 손상이 관여하고 있으며, CM 추출물은 항산화 효과에 의하여 $CdCl_2$의 세포독성에 대한 방어효과를 나타냈다. 결론적으로, CM 추출물과 같은 천연소재는 산화적 손상과 관련된 독성의 제독 내지는 저감을 위한 항산화물질로서의 개발적 가치가 있다고 사료된다.

• Journal of Microbiology
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• 제35권4호
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• pp.309-314
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• 1997

The manganese-containing superoxide dismutase (MnSOD) is a major component of the cellular defence mechanisms against the toxic effects of the superoxide radical. Within the framework of studies on oxidative stress=responsible enzymes in the Candida sp., the gene encoding the MnSOD was isolated and examined in this study. A specific primer was designed based on conserved regions of MnSOD sequences from other organisms, and was used to isolate the gene by PCR on reverse-transcribed Candida poly($A^{+}$) RNA. The PCR product was used to screen a Candida genomic lambda library and the nucleotide wequence of positive clone was determined. The deduced primary sequence encodes a 25kDa protein which has the conserved residues for enzyme activity and metal binding. The 28 N-terminal amino acids encoded by the Candida cDNA comprise a putatice mitochondrial transit peptide. Potential regulatory elements were identified in the 5' flanking sequences. Northern blot analysis showed that the transcription of the MnSOD gene is induced 5-to 10-fold in response to mercury, cadmium ions and hydrogen peroxide.

• Molecules and Cells
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• 제23권1호
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• pp.100-107
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• 2007

The moss Physcomitrella patens has two life cycles, filamentous protonema and leafy gametophore. A modified from of suppression subtractive hybridization (SSH), mirror orientation selection (MOS), was applied to screen genes differentially expressed in the P. patens protonema. Using reverse Northern blot analysis, differentially expressed clones were identified. The identified genes were involved mainly in metal binding and detoxification. One of these genes was an AP2 (APETALA2) domain-containing protein (PpACP1), which was highly up-regulated in the protonema. Alignment with other AP2/EREBPs (Ethylene Responsive Element Binding Proteins) revealed significant sequence homology of the deduced amino acid sequence in the AP2/EREBP DNA binding domain. Northern analysis under various stress conditions showed that PpACP1 was induced by ethephon, cadmium, copper, ABA, IAA, and cold. In addition, it was highly expressed in suspension-cultured protonema. We suggest that PpACP1 is involved in responses to metals, and that suspension culture enhance the expression of genes responding to metals.

• Journal of Ginseng Research
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• 제32권2호
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• pp.114-119
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• 2008

Terpene synthase plays a key role in biosynthesis of triterpene saponins (ginsenosides) and is intermediate in the biosynthesis of a number of secondary metabolites. A terpene synthase (PgTPS) cDNA was isolated and characterized from the root of Panax ginseng c.A. Meyer. The deduced amino acid sequence of PgTPS showed a similarity with A. deliciosa (AAX16121) 61%, V. vinifera (AAS66357) 61%, L. hirsutum (AAG41891) 55%, M. truncatula (AAV36464) 52%. And the segment of a terpene synthase gene was amplified by reverse transcriptase-polymerase chain reaction (RTPCR). We studied expression of terpene synthase under stressful conditions like chilling, salt, UV, and heavy metal stress treatment. Expression of PgTPS was increased gradually after exposure to stresses such as chilling, salt, and UV illumination. But its transcription seems to be reduced by cadmium and copper treatment.

• Journal of Applied Biological Chemistry
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• 제60권2호
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• pp.113-117
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• 2017

생물학적정화는 미생물을 이용하여 중금속을 포함한 오염물질을 정화하는 방법이다. 효모는 다양한 중금속을 흡착하여 정화하는 능력이 우수하다고 잘 알려졌다. 따라서 본 연구는 여러 중금속 중 하나인 아연에 저항성인 큰 효모를 인위적인 돌연변이를 통해서 얻는 것에 초점을 두었다. 대조구인 효모를 1 mM 농도의 아연이 포함된 배지에서 키운 후 점차 아연의 농도를 높여 최종적으로 80 mM이 되는 지점까지 키웠으며 이 농도는 효모가 점진적 적응을 거쳤어도 성장이 불가능한 한계점 근처이며 이렇게 유도 분리된 효모를 ZnR이라 명명하였다. ZnR은 대조구 효모보다 아연에 대한 저항성이 현저히 증가되었으며 이 외에 카드뮴과 니켈에 대한 저항성도 증가되었지만 구리에 대한 저항성은 오히려 감소 되었다. ZnR이 보여준 아연에 대한 저항성 증가는 유전자 돌연변이에 의한 영구적인 획득 결과이다. 단 기간 내에 아연에 대한 저항성 큰 효모의 인위적인 유도 및 분리는 생물학적정화 연구에 유용하게 쓰여질 정보이다.

• Fisheries and Aquatic Sciences
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• 제12권3호
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• pp.179-184
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• 2009

Hemibarbus mylodon (Cypriniformes) is an endemic freshwater fish species in the Korean peninsula, for which urgent conservation efforts are needed. To understand their stress responses in relation to metal toxicity and thermal elevation, we performed a real-time RT-PCR-based expression assay of hepatic copper/zinc-superoxide dismutase (Cu/Zn-SOD), a key antioxidant enzyme, in response to experimental heavy metal exposure or heat treatment. The transcription of hepatic Cu/Zn-SOD was differentially modulated by acute exposure to Cu, cadmium (Cd), or Zn. Exposure to each metal at $5{\mu}M$ for 24 h revealed that Cu stimulated the mRNA expression of Cu/Zn-SOD to a greater extent than the other two heavy metals. The elevation in Cu/Zn-SOD transcripts in response to Cu exposure was dose-dependent (0.5 to $5{\mu}M$). Time course analysis of Cu/Zn-SOD expression in response to Cd exposure ($5{\mu}M$) revealed a transient pattern up to day 7. Exposure to thermal stress (an increase from 22 to $30^{\circ}C$ at a rate of $1^{\circ}C/h$ followed by $30^{\circ}C$ for 18 h) did not significantly alter SOD transcription, although heat shock protein 90 kDa (HSP90) transcription was positively correlated with an increase in temperature.

• BMB Reports
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• 제36권3호
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• pp.326-331
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• 2003

The fission yeast cells that contained the cloned glutathione synthetase (GS) gene showed 1.4-fold higher glutathione (GSB) content and 1.9-fold higher GS activity than the cells without the cloned GS gene. Interestingly, $\gamma$-glutamylcysteine synthetase activity increased 2.1-fold in the S. pombe cells that contained the cloned GS gene. The S. pombe cells that harbored the multi copy-number plasmid pRGS49 (containing the cloned GS gene) showed a higher level of survival on solid media with cadmium chloride (1 mM) or mercuric chloride ($10\;{\mu}M$) than the cells that harbored the YEp357R vector. The 506 bp upstream sequence from the translational initiation point and N-terminal8 amino acid-coding region were fused into the promoteriess $\beta$-galactosidase gene of the shuttle vector YEp367R to generate the fusion plasmid pUGS39. Synthesis of $\beta$-galactosidase from the fusion plasmid pUGS39 was significantly enhanced by cadmium chloride and NO-generating S-nitroso-N-acetylpenicillamine (SNAP) and sodium nitroprusside (SN). It was also induced by L-buthionine-(S,R)-sulfoximine, a specific inhibitor of $\gamma$-glutamylcysteine synthetase (GCS). We also found that the expression of the S. pombe GS gene is regulated by the Atf1-Spc1-Wis1 signal pathway.

• 공업화학
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• 제34권6호
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• pp.640-648
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• 2023

The purpose of this study was to determine the inhibitory effect of heavy metals [Cd(II), Ni(II), and Zn(II)] on the growth of Rhodobacter species (Rhodobacter blasticus, Rhodobacter sphaeroides, and Rhodobacter capsulatus) and their potential use for Cd(II), Ni(II), and Zn(II) bioremoval from liquid media. The presence of toxic heavy metals prolonged the lag phase in growth and reduced biomass growth for all three Rhodobacter species at concentrations of Cd, Ni, and Zn above 10 mg/L. However, all three Rhodobacter species also had a relatively high specific growth rate against each toxic heavy metal stress test for concentrations below 20 mg/L and possessed a potential bioaccumulation ability. The removal efficiency by all strains was highest for Cd(II), followed by Ni(II), and lowest for Zn(II), with the removal efficiency of Cd(II) by Rhodobacter species being 66% or more. Among the three strains, R. blasticus showed a higher removal efficiency of Cd(II) and Ni(II) than R. capsulatus and R. sphaeroides. Results also suggest that the bio-removal processes of toxic heavy metal ions by Rhodobacter species involve both bioaccumulation (intracellular uptake) and biosorption (surface binding).

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1557-1567
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• 2012

Glutathione reductase (GR, E.C. 1.6.4.2) is an important enzyme that reduces glutathione disulfide (GSSG) to a sulfydryl form (GSH) in the presence of an NADPH-dependent system. This is a critical antioxidant mechanism. Owing to the significance of GR, this enzyme has been examined in a number of animals, plants, and microbes. We performed a study to evaluate the molecular properties of GR (OsGR) from rice (Oryza sativa). To determine whether heterologous expression of OsGR can reduce the deleterious effects of unfavorable abiotic conditions, we constructed a transgenic Saccharomyces cerevisiae strain expressing the GR gene cloned into the yeast expression vector p426GPD. OsGR expression was confirmed by a semiquantitative reverse transcriptase polymerase chain reaction (semiquantitative RT-PCR) assay, Western-blotting, and a test for enzyme activity. OsGR expression increased the ability of the yeast cells to adapt and recover from $H_2O_2$-induced oxidative stress and various stimuli including heat shock and exposure to menadione, heavy metals (iron, zinc, copper, and cadmium), sodium dodecyl sulfate (SDS), ethanol, and sulfuric acid. However, augmented OsGR expression did not affect the yeast fermentation capacity owing to reduction of OsGR by multiple factors produced during the fermentation process. These results suggest that ectopic OsGR expression conferred acquired tolerance by improving cellular homeostasis and resistance against different stresses in the genetically modified yeast strain, but did not affect fermentation ability.