• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.274-276
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• 2001

This research aims to develop the multiple channel electrochemical DNA chip using microfabrication technology. At first, we fabricated a high integration type DNA chip array by lithography technology. Several probe DNAs consisting of thiol group at their 5-end were immobilized on the sold electrodes. Then target DNAs were hybridized and reacted. Cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. Therefore, it is able to detect a plural genes electrochemically after immobilization of a plural probe DNA and hybridization of non-labeling target DNA on the electrodes simultaneously. It suggested that this DNA chip could recognize the sequence specific genes.

• 한국자기공명학회논문지
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• 제20권3호
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• pp.71-75
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• 2016

The replication protein A (RPA) plays a crucial role in DNA replication, recombination, and repair. RPA consists of 70, 32 and 14 kDa subunits and has high single-stranded DNA (ssDNA) binding affinity. The largest subunit, RPA70, mainly contributes to bind to ssDNA as well as interact with many cellular and viral proteins. In this study, we performed nuclear magnetic resonance experiments on the complex of the DNA binding domain A of human RPA70 (RPA70A) with ssDNA, d(CCCCC), at various pH, to understand the effect of pH on the ssDNA binding of RPA70A. The chemical shift perturbations of binding residues were most significant at pH 6.5 and they reduced with pH increment. This study provides valuable insights into the molecular mechanism of the ssDNA binding of human RPA.

• 한국균학회지
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• 제27권1호통권88호
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• pp.20-26
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• 1999

우리나라에서 자생하는 송이버섯의 구분 방법으로 제조된 OPO-2 primer을 사용할 때 송이에게만 특이적인 band가 나타났다. 그리고 제한효소 처리와 dot blot의 결과에서 이들 특이적인 DNA절편은 송이 genomic DNA에서 한개의 copy만 존재하는 것으로 나타났으며, 다른 외생균근 버섯의 DNA에서는 발견되지 않았다. 또한, 이들 DNA 절편의 염기서열을 분석한 결과 770bps로 나타났다. 이러한 유전자의 정보를 이용한 NCBI Blast 염기서열 분석에서 높은 상동성을 갖는 유전자는 발견할 수가 없었고, 단백질서열 분석에서도 거의 동일하게 나타났다. 따라서 translation통한 아미노산 서얼분석에서 이들 DNA절편의 유전자는 단백질에 관한 유전자이라기 보다는 다른 정보와 관련된 유전자로 생각되어진다.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1618-1622
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• 2006

Bacteriophage T7 gp4A' is a ring-shaped hexameric DNA helicase that catalyzes duplex DNA unwinding using dTTP hydrolysis as an energy source. To investigate the effect of single-stranded DNA (ssDNA) on the kinetic pathway of dTTP hydrolysis by the T7 DNA helicase complexed with ssDNA, we have first determined optimal concentration of long circular M13 single-stranded DNA and pre-incubation time in the absence of $Mg^{2+}$ which is necessary for the helicase-ssDNA complex formation. Steady state dTTP hydrolysis in the absence of $Mg^{2+}$ by the helicase-ssDNA complex provided $k_{cat}$ of $8.5\;{\times}\;10^{-3}\;sec^{-1}$. Pre-steady state kinetics of the dTTP hydrolysis by the pre-assembled hexameric helicase was monitored by using the rapid chemical quench-flow technique both in the presence and absence of M13 ssDNA. Pre-steady state dTTP hydrolysis showed distinct burst kinetics in both cases, indicating that product release step is slower than dTTP hydrolysis step. Pre-steady state burst rates were similar both in the presence and absence of ssDNA, while steady state dTTP hydrolysis rate in the presence of ssDNA was much faster than in the absence of ssDNA. These results suggest that single-stranded DNA stimulates dTTP hydrolysis reaction by T7 helicase by enhancing the rate of product release step.

• Journal of Radiation Protection and Research
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• 제20권2호
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• pp.71-78
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• 1995

본 연구에서는 유전자 손상회복에 관여하는 단백질을 이용하여 돌연변이 생성을 억제시키는 물질로서 알려진 cobaltous chloride가 유전자 손상회복에 미치는 영향을 연구하므로서 방사선으로 인한 손상방지 및 방사선 방어효과에 대한 적용가능성을 평가하였다. Cobaltous chloride가 RecA 단백질의 기능에 미치는 영향을 조사한 결과 RecA 단백질에 의한 DNA strand exchange 반웅에 있어 cobaltous chloride 처리로 RecA 단백질이 $_{ss}DNA$로 부터 SSB 단백질과 더 효과적으로 경쟁함으로써 안정된 $RecA-_{ss}DNA$ complex의 형성을 유도하고, 증가된 ATPase활성에 의한 ATP 가수분해로 손상된 DNA의 회복이 촉진될 수 있다는 사실을 입증 해주고 있다. 또한 RecA단백질은 UV에 의해 손상된 supercoiled DNA에 더 효과적으로 결합됨이 관찰되었으며 UV 선량과도 상관관계가 있음을 확인하였다. 따라서 이와 같은 연구결과들은 방사선으로 인한 유전적인 손상방지 및 방사선 방어효과에 관한 연구에 적용될 수 있을 것으로 기대된다.

• Natural Product Sciences
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• 제16권4호
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• pp.223-227
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• 2010

The DNA Topoisomerase I (DNA Topo I) inhibitory effect of ten isolated compounds (1.10) from the leaf and stem of Vitis amurensis were examined. Among them, amurensin G (5) and r-2-viniferin (7) showed high potent inhibitory activity against DNA Topo I. DNA Topo I, an important target for anticancer drugs, can cause DNA breaks and play a key role during cell proliferation, transcription and repair. Thus, the results suggest that the selected compounds (5 and 7) from Vitis amurensis have a possibility as DNA Topo I-targeting anticancer agents.

• Mass Spectrometry Letters
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• 제6권3호
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• pp.80-84
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• 2015

Here, we demonstrate the use of MALDI-TOF as a fast and simple analytical approach to evaluate the DNA-binding capability of various peptides. Specifically, by varying the amino acid sequence of the peptides consisting of lysine (K) and tryptophan (W), we identified peptides with strong DNA-binding capabilities using MALDI-TOF. Mass spectrometric analysis reveals an interesting novel finding that lysine residues show sequence selective preference, which used to be considered as mediator of electrostatic interactions with DNA phosphate backbones. Moreover, tryptophan residues show higher affinity to DNA than lysine residues. Since there are numerous possible combinations to make peptide oligomers, it is valuable to introduce a simple and reliable analytical approach in order to quickly identify DNA-binding peptides.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1375-1376
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• 2007

A synthesized 21-mer single-stranded DNA(ss DNA) was covalently immobilized onto a self-assembled aminoethanethiol monolayer modified gold electrode onto QCM. The covalently immobilized ssDNA was hybridized with complementary ssDNA. The interaction between surface immobilized ssDNA and complementary 21-mer DNA in solution was also examined. Each step was followed by monitoring changes in the QCM frequency with time. Also, PBS with pH 7.0 was selected as a supporting electrolyte in order to get maximum sensitivity and good bioactivity.

• BMB Reports
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• 제33권1호
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• pp.75-81
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• 2000

DnaK is a major heat shock protein and known to be highly conserved in all species. Previously, the dnaK in Streptococcus pneumoniae was cloned and the immunogenic nature characterized. In this study, dnaK mutants were generated by insertion of duplication mutagenesis and their characteristics examined. They had defective growths at all temperatures ($20^{\circ}C-42^{\circ}C$)and cell divisions, and formed filaments after a temperature shift from 30 to 42. A unique feature of the dnaK mutants of S. pneumoniae, unlike those of E. coli and B. subtilis, was the growth capability at high temperature ($42^{\circ}C$) without producing the putative GroEL. Our results suggest that DnaK may serve as a regulator and/or modifier in GroEL gene expression.

• 한국수산과학회지
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• 제20권4호
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• pp.300-307
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• 1987

어유의 산화에 의한 DNA 손상작용기구를 밝히는 연구의 일환으로 고등어에서 추출한 지질을 다시 극성 및 비극성지질로 분획하여 이들을 각각 plasmid DNA와 $37^{\circ}C$에서 반응시키면서 이들 지질의 산화에 의한 DNA 손상작용을 $1\%$ agarose gel 전기영동을 통하여 조사하였는데 그 결과를 요약하면 다음과 같다. 극성지질을 DNA와 반응시킨 경우에는 가장 적은 농도에서도 DNA 손상작용이 크게 나타나 반응 l일째에 Form I DNA가 완전히 절단되어 Form II 및 Form III DNA로서 검출되었다. 극성지질의 산화에 의하여 그 농도가 증가함에 따라 POV의 증가가 빠르게 이루어졌으나 반응 4일동안 POV가 100 millieq./kg 이하에서 DNA 손상작용이 일어나는 것을 알 수 있었고, 한편, 극성지질의 산화에 의한 DNA 손상작용에 대한 활성산소종의 영향에서는 총지질의 경우처럼 일중항산소 $^1O_2$와 superoxide anion ${\cdot}O_2^1$의 영향이 가장 컸으며 수산 radical${\cdot}OH$과 과산화수소$(H_2O_2)$는 그다지 뚜렷한 영향을 나타내지 않았다. 비극성지질의 경우에서도 극성지질과 마찬가지로 농도에 따라 DNA 손상능이 커졌으나 극성지질과 총지질에 비하여 그 정도가 훨씬 떨어지는 것을 알 수 있었으며, 이상의 DNA 손상작용에 대한 활성산소종의 영향에 있어서도 극성지질과 동일한 경향을 나타내었다.