• Fisheries and Aquatic Sciences
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• 제16권4호
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• pp.311-318
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• 2013

The gene encoding an esterase from Photobacterium sp. MA1-3 was cloned in Escherichia coli using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (948 bp) corresponded to a protein of 315 amino acid residues with a molecular weight of 35 kDa and a pI of 6.06. The deduced protein showed 74% and 68% amino acid sequence identities with the putative esterases from Photobacterium profundum SS9 and Photobacterium damselae, respectively. Absence of a signal peptide indicated that it was a cell-bound protein. Sequence analysis showed that the protein contained the signature G-X-S-X-G included in most serine-esterases and lipases. The MA1-3 esterase was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at $18^{\circ}C$. The enzyme was a serine-esterase and was active against $C_2$, $C_4$, $C_8$ and $C_{10}$ p-nitrophenyl esters. The optimum pH and temperature for enzyme activity were pH 8.0 and $30^{\circ}C$, respectively. Relative activity remained up to 45% even at $5^{\circ}C$ with an activation energy of 7.69 kcal/mol, which indicated that it was a cold-adapted enzyme. Enzyme activity was inhibited by $Cd^{2+}$, $Cu^{2+}$, $Zn^{2+}$, and $Hg^{2+}$ ions.

• 한국잠사학회:학술대회논문집
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• 한국잠사학회 1997년도 Progress and Future Development of Sericultural Science and Technology 40th Anniversary Commemoration Symposium
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• pp.73-101
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• 1997

Baculoviruses are characterized by large double-stranded circular DNA genomes and rod-shaped enveloped virions. Bombyx mori nucleopolyhedrovirus(BmNPV) is a major pathogen, which causes severe damage in sericulture. Currently, BmNPV is recogtnized as an improtant tool in molecular biology, especially for expression of useful genes in B.mori cells and silkworm larvae. Our laboratories have focused on the studies of the molecular mechanisms of BmNPV replication and the application of BmNPV to agriculture and medicine. The entire nucleotide sequence of the BmNPV genome has recently determined. The BmNPV genome possessed 135 putative genes and 7 homologous repeated sequence (hrs) regions. Relatively little space, a few to a few hundred base-pairs, was observed between the open reading frames and hrs. Termination codons often overlapped. These results showed a compactly packde BmNPV genome. Based on comparative sequence analyses, we speculated that the ancestor of BmNPV was a baculovirus similar to Autographa californica NPV(AcNPV). The function of the BmNPV genes were characterized by gene deletion analysis; p35 was found to be involved in blocking apoptosis and cysteine proteinase was found to be involved in horizontal virus transmission by degrading viral-infected larval host. By AcNPV and BmNPV coinfection experiments, we identified a BmNPV gene involved in expanding host specificity of AcNPV. The identified gene was likely encoded a DNA helicase based on the amino acid sequence analysis; a few amino acid substitutions in the putative DNA helicase gene resulted in the expansion of host range of AcNPV. These findings indicate that BmNPV evolved within a short period from an AcNPV-like ancestral virus due to rapid evolution including specific amino acid substitutions and gene deletions/insertions.

• Journal of Life Science
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• 제11권1호
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• pp.57-64
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• 2001

The cDNA encoding human NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc GalNac ${\alpha}$2,6-Sialyltransferase (hST6GalNac IV) was isolated by screening of human fetal liver cDNA library with a DNA probe generated from the cDNA sequence of mouse ST6Gal NAc IV (mkST6GalNAc IV). The cDNA sequence included an open reading frame coding for 302 amino acids, and comparative analysis of this cDNA with mST6GalNAc IV showed that each sequence of the predicted coding region contains 88% and 85% identifies in nucleotide and amino acid levels, respecively. The primary structure of this enzyme suggested a putative domain structure, like that in other glycosyltransferases, consisting of a short N-terminal cytoplamic domain, a transmembrane domain and a large C-terminal active domain. This enzyme expressed in COS-7 cells echibited transferase activity toward NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc, fetuin and GM1b, although the activity toward the later is very low, no significant activity being detected toward Gal${\beta}$ 1,3Gal NAc or asialofetuin, the other glycoprotein substrates tested. The $^{14}$ C-sialylated residue of fetuin sialylated by this enzyem with CMP-[$^{14}$C]NeuAc was sensitive to treatment with ${\alpha}$2,8-specific sialidase of Vibrio cholerae but resistant to treatment with ${\alpha}$2,3-specific sialidase (NaNase I), and ${\alpha}$2,3- and ${\alpha}$2,8-specific sialidase of Newcastle disease virus. These results clearly indicated that the expressed enzyme is a type of GalNAc ${\alpha}$2,6-sialyltransferase like mST6GalNAc IV, which requires sialic acid residues linked to Gal${\beta}$1,3GalNAc-residues for its activity.

• 생명과학회지
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• 제15권3호
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• pp.474-478
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• 2005

본 연구는 RAPD 기법을 이용한 종 특이 marker 개발 및 이 marker의 SCAR marker로의 개발을 목표로 수행되었다. Random primer 700개에 대하여 PCR 수행결과, 품종간, 개체간에 많은 다형성이 관찰되었으며 품종특이적인 양상을 나타내는 MG30, MG53의 primer는 각각 2.0kb, 2.3kb의 위치에서 제주말과 더러브렛종의 특이적인 RAPD 단편을 나타내었다. 이들 단편들 중 품종 특이적인 단편을 클로닝한 후 random primer가 포함된 부분의 염기서 열을 결정하였다. 10 bp의 RAPD random primer에 10bp의 염기를 추가하여 SCAR primer를 제작하였다. SCAR marker의 수행결과 RAPD marker와 같은 2.3kb, 2.0kb의 크기에서 제주마와 더러브렛종에 특이적인 하나의 밴드가 증폭되었다. 따라서 이 Cnh-SCAR marker는 보다 안정적이고 재현성 있는 marker로서 사용이 가능하여 제주말의 판별에 유용하게 사용될 수 있을 것이다.

• 생명과학회지
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• 제21권7호
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• pp.947-952
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• 2011

현재까지 다수의 역학연구를 통해 피부에 발생한 보통사마귀에서 제 1, 2, 3, 4, 7, 10, 27, 57 및 65형의 인유두종바이러스가 검출되었다. 그러나 기존의 중합효소연쇄반응(conventional polymerase chain reaction, PCR)을 이용하는 경우 절차가 복잡하여 시간이 오래 걸리는 단점이 있었다. 이번 연구를 통해 저자들은 보통사마귀에서 가장 흔히 검출되는 6가지 유전자형의 인유두종바이러스를 한번에 확인 가능한 간편한 muliplex PCR의 개발을 목표로 하였다. 인유두종바이러스의 염기서열분석을 통해, L1에서 E6, 그리고 E2에서 L2 사이의 유전자간영역(intergenic region)으로 부터 6쌍의 primer를 고안하였으며, L1 유전자서열 분석을 통해 multiplex PCR의 특이성을 확인하였다. 총 129개의 조직표본 중 109개에서 제 1, 2, 3, 4, 27, 57형의 인유두종바이러스를 확인하였다. 이번 연구의 primer를 이용한 인유두종바이러스 검출의 민감도와 특이도는 각각 85%와 99.5%였다. 이러한 primer 세트로 인유두종바이러스가 검출되지 않은 20개의 조직표본의 경우, 또 다른 HPV primer를 사용한 추가적인 multiplex PCR을 시행하여 7개 표본에서 제 7형 및 65형의 인유두종바이러스가 검출되었다. 이상의 결과는 본 연구를 통해 새롭게 고안된 multiplex PCR 기법을 통해 보통사마귀에서의 인유두종바이러스를 보다 정확하고 빠르게 검출할 수 있다는 것을 보여 준다.

• 생명과학회지
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• 제18권3호
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• pp.374-380
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• 2008

본 연구는 무균성수막염 의심환자의 다양한 검체로부터 enterovirus의 진단을 위하여 real-time NASBA, 2 step RT-PCR 시험과 세포배양 시험을 각각 실시하여 각 시험법의 검출율, 특이도, 사용자 편리성, 시험소요 시간, 교차오염의 가능성 등을 비교 검토하였다. 비교시험 결과 전체 292건의 검체로부터 real-time NASBA에서 145건, 세포배양에서 101건, 2 step RT-PCR에서 86건이 양성으로 나타나 real-time NASBA가 가장 검출율이 높은 시험법임을 알 수 있었다. Enterovirus 외의 무균성수막염 원인바이러스에 대한 특이도 비교 시험결과 2 step RT-PCR 시험에서 rhinovirus 10건 중 1건이 위양성 반응을 나타내어 다른 시험법에 비해 특이도가 떨어지는 것으로 나타났다. Real-time NASBA는 하나의 튜브에서 증폭과 검출이 동시에 일어나 다른 시험과 비교하여 교차오염의 가능성이 낮으며 또한 시험 소요시간이 5시간 정도로 세포배양(5-14일 소요) 및 2 step RT-PCR(9시간소요) 에 비하여 신속하게 진단할 수 있어 일선병원이나 실험실에서 enterovirus를 검출을 위하여 적용할 수 있을 것으로 사료된다.

• BMB Reports
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• 제48권1호
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• pp.6-12
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• 2015

Various biological molecules naturally existing in diversified species including fungi, bacteria, and bacteriophage have functionalities for DNA binding and processing. The biological molecules have been recently actively engineered for use in customized genome editing of mammalian cells as the molecule-encoding DNA sequence information and the underlying mechanisms how the molecules work are unveiled. Excitingly, multiple novel methods based on the newly constructed artificial molecular tools have enabled modifications of specific endogenous genetic elements in the genome context at efficiencies that are much higher than that of the conventional homologous recombination based methods. This minireview introduces the most recently spotlighted molecular genome engineering tools with their key features and ongoing modifications for better performance. Such ongoing efforts have mainly focused on the removal of the inherent DNA sequence recognition rigidity from the original molecular platforms, the addition of newly tailored targeting functions into the engineered molecules, and the enhancement of their targeting specificity. Effective targeted genome engineering of mammalian cells will enable not only sophisticated genetic studies in the context of the genome, but also widely-applicable universal therapeutics based on the pinpointing and correction of the disease-causing genetic elements within the genome in the near future.

• BMB Reports
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• 제28권4호
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• pp.353-358
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• 1995

Epitope tagging is the process of fusing a set of amino acid residues that are recognized as an antigenic determinant to a protein of interest. Tagging a protein with an epitope facilitates various immunochemical analyses of the tagged protein with a specific monoclonal antibody. The monoclonal antibody H8 has subtype specificity for an epitope derived from the preS2 region of hepatitis B virus surface antigen. Previous studies on serial deletions of the preS2 region indicated that the preS2 epitope was located in amino acid residues 130~142. To test whether the amino acid sequence in this interval is sufficient to confer on proteins the antigenicity recognizable by the antibody H8, the set of amino acid residues in the interval was tagged to the amino terminal of ${\beta}$-galactosidase and to the carboxyl terminal of the truncated $p56^{lck}$ fragment. The tagged ${\beta}$-galactosidase, expressed in Escherichia coli, maintained the enzymatic activity and was immunoprecipitated efficiently with H8. The tagged $p56^{lck}$ fragment, synthesized in an in vitro translation system, was also immunoprecipitated specifically with H8. These results demonstrate that the amino acid sequence of the preS2 region can be used efficiently for the epitope tagging approach.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.69-79
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• 2011

HP0827 has two RNP motif which is a very common protein domain involved in recognition of a wide range of ssRNA/DNA.We acquired 3D NMR spectra of HP0827 which shows well dispersed and homogeneous signals which allows us to assign 98% of all $^1H_N$, $^{15}N$, $^{13}C_{\alpha}$, $^{13}C_{\beta}$ and $^{13}C$=O resonances and 90% of all sidechain resonances. The sequence-specific backbone resonance assignment of HP0827 can be used to gain deeper insights into the nucleic acids binding specificity of HP0827 in the future study. Here, we report secondary structure prediction of HP0827 derived from NMR data. Additionally, ssRNA/DNA binding assay studies was also conducted. This study might provide a clue for exact function of HP0827 based on structure and sequence.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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• pp.5-5
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• 2003

The purple acid phosphatases comprise a family of binuclear metal-containing enzymes. The metal centre contains one ferric ion and one divalent metal ion. Spectroscopic studies of the monomeric, ${\sim}$36 kDa mammalian purple acid phosphatases reveal the presence of an Fe(III)Fe(II) centre in which the metals are weakly antiferromagnetically coupled, whereas the dimeric, ${\sim}$110 000 kDa plant enzymes contain either Fe(III)Zn(II) or Fe(III)Mn(II). The three dimensional structures of the red kidney bean and pig enzymes show very similar arrangements of the metal ligands but some significant differences beyond the immediate vicinity of the metals. In addition to the catalytic domain, the plant enzyme contains a second domain of unknown function. A search of sequence databases was undertaken using a sequence pattern which includes the conserved metal-binding residues in the plant and animal enzymes. The search revealed the presence in plants of a 'mammalian-type' low molecular weight purple acid phosphatase, a high molecular weight form in some fungi, and a homologue in some bacteria. The catalytic mechanism of the enzyme has been investigated with a view to understanding the marked difference in specificity between the Fe-Mn sweet potato enzyme, which exhibits highly efficient catalysis towards both activated and unactivated phosphate esters, and other PAPs, which hydrolyse only activated esters. Comparison of the active site structures of the enzymes reveal some interesting differences between them which may account for the difference. The implications fur understanding the physiological functions of the enzymes will be discussed.