• 에너지공학
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• 제12권2호
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• pp.109-117
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• 2003

신규 발전소 부지 및 송전선 경과지 확보의 어려움 때문에 신규 발전기들은 기존의 발전단지에 건설되고 송전망은 더 복잡한 망의 형태로 구성되고 있다. 이러한 구조적인 특징은 전력계통의 운용의 신뢰성에 제약을 발생시킨다. 이러한 문제를 해결하기 위해서 전력계통의 해석의 고도화와 적절한 대책이 요구된다. 또한 현재 진행중인 전력산업의 구조 개편 이후, 신뢰성과 경제성을 동시에 추구하여야하는 경쟁적 전력시장에서의 계통해석 결과에 따른 비용 발생시에 책임소재의 투명성과 해석결과에 대한 검증이 필요하게 되어 계통해석 기술의 고도_화와 이를 구현하기 위한 해석 프로그램의 다변화가 절실하게 요구된다. 본 논문에서는 대규모 전력계통 해석 프로그램인 EUROSTAG의 발전기 제어계 계통 의 모델을 개발하였고, 성능을 입증하기 위해서 현재 전력회사에서 사용되는 PSS/E와 시뮬레이션 결과를 비교하였다.

• BMB Reports
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• 제34권6호
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• pp.502-508
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• 2001

A cDNA, encoding the human growth hormone (hGH), was synthesized based on the known 191 amino acid sequence. Its codon usage was optimized for a high level expression in Escherichia coli. Unique restriction sites were incorporated throughout the gene to facilitate mutagenesis in further studies. To minimize an initiation translation problem, a 624-bp cassette that contained a ribosome binding site and a start codon were fused to the hGH-coding sequence that was flanked between the EcoRI and HindIII sites. The whole fragment was synthesized by an overlapped extension of eight long synthetic oligonucleotides. The four-short duplexes of DNA, which were first formed by annealing and filling-in with a Klenow fragment, were assembled to form a complete hGH gene. The hGH was cloned and expressed successfully using a pET17b plasmid that contained the T7 promoter. Recombinant hGH yielded as much as 20% of the total cellular proteins. However, the majority of the protein was in the form of insoluble inclusion bodies. N-terminal amino acid sequencing also showed that the hGH produced in E. coli contained formyl-methionine. This study provides a useful model for synthesis of the gene of interest and production of recombinant proteins in E. coli.

• Journal of Yeungnam Medical Science
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• 제12권2호
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• pp.237-245
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• 1995

Klebsiella pneumoniae 의 phoA 유전자를 함유하는 DNA를 plasmid pACYC184에 클로닝 하였다. 클로닝된 DNA의 크기는 4.0 kb이었으며 제한효소지도를 작성한 결과 3개의 PstI 절단부위와 4개의 PvuII 절단부위가 발견되었다. Klebsiella pneumoniae 의 phoA 유전자의 염기서열은 Escherichia coli와 매우 유사하여 80%의 유사성을 보였으며 이는 이 두 균종이 서로 유전적으로 매우 가까운 관계에 있음을 시사하였다.

• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.620-627
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• 2000

To determine the prevalence of genetic polymorphisms in Epstein-Barr virus (EBV) strains in the Korean population, the restriction site polymorphisms for BamHI and XhoI enzymes were analyzed with 16 EBV isolates from cancer patients and 7 EBV isolates from healthy carriers, using polymerase chain reaction techniques. None of the 23 isolates were found to carry an extra BamHI site in the BamHI F-fragment (f-variant). Of the 12 type-1 isolates from the cancer patients, 10 lost both the LMP1 XhoI site and the BamHI site between the BamHi W1* and I1* fragments (a W1*I1* fusion variant or type C). The latter W1*I1* fusion variant was due to a mutation of thymidine to adenine, as evidenced by a sequence analysis. The remaining two type-1 isolates showed either no variation at both sites or the loss of only the XhoI site. In contrast, two type-2 isolates and two intertypic recombinants with a type-1 allele at the EBNA2 locus and type-2 alleles at all or some of the EBNA3 loci retained both enzyme sites. In similar analyses of the 7 isolates from the healthy carriers, five of six type-1 isolates lost these two sites, however, one type-2 isolate did not. These results clearly indicate a strong association of both the LMP1 XhoI site loss and the W1*I1* fusion variant with the type-1 rather than the type-2 EBV strains circulating in the immunocompetent Korean carriers.

• Genomics & Informatics
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• 제13권2호
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• pp.53-59
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• 2015

In developing countries threat of cholera is a significant health concern whenever water purification and sewage disposal systems are inadequate. Vibrio cholerae is one of the responsible bacteria involved in cholera disease. The complete genome sequence of V. cholerae deciphers the presence of various genes and hypothetical proteins whose function are not yet understood. Hence analyzing and annotating the structure and function of hypothetical proteins is important for understanding the V. cholerae. V. cholerae O139 is the most common and pathogenic bacterial strain among various V. cholerae strains. In this study sequence of six hypothetical proteins of V. cholerae O139 has been annotated from NCBI. Various computational tools and databases have been used to determine domain family, protein-protein interaction, solubility of protein, ligand binding sites etc. The three dimensional structure of two proteins were modeled and their ligand binding sites were identified. We have found domains and families of only one protein. The analysis revealed that these proteins might have antibiotic resistance activity, DNA breaking-rejoining activity, integrase enzyme activity, restriction endonuclease, etc. Structural prediction of these proteins and detection of binding sites from this study would indicate a potential target aiding docking studies for therapeutic designing against cholera.

• BMB Reports
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• 제38권2호
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• pp.191-197
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• 2005

Although the human genome has been nearly completely sequenced, the functions and the roles of the vast majority of the genes, and the influences of single nucleotide polymorphisms (SNPs) in these genes are not entirely known. A modified mutation detection method was developed for large-scale cloning of the possible SNPs between tumor and normal cells for facilitating the identification of genetic factors that associated with cancer formation and progression. The method involves hybridization of restriction enzyme-cut chromosomal DNA, cleavage and modification of the sites of differences by enzymes, and differential cloning of sequence variations with a designed vector. Experimental validations of the presence and location of sequence variations in the isolated clones by PCR and DNA sequencing support the capability of this method in identifying sequence differences between tumor cells and normal cells.

• BMB Reports
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• 제36권3호
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• pp.305-311
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• 2003

A modified actinomycin D was prepared with a hydroxyl group that replaced the amino group at the chromophore 2-position, a substitution known to strongly reduce affinity for double-stranded DNA. Interactions of the modified drug on single-stranded DNAs of the defined sequence were investigated. Competition assays showed that 2-hydroxyactinomycin D has low affinity for two oligonucleotides that have high affinities ($K_a\;=\;5-10{\times}10^6\;M^{-1}$ oligomer) for 7-aminoactinomycin D and actinomycin D. Primer extension inhibition assays performed on several single-stranded DNA templates totaling around 1000 nt in length detected a single high affinity site for 2-hydroxyactinomycin D, while many high affinity binding sites of unmodified actinomycin D were found on the same templates. The sequence selectivity of 2-hydroxyactinomycin D binding is unusually high and approximates the selectivity of restriction endonucleases. Binding appears to require a complex structure, including residues well removed from the polymerase pause site.

• Journal of Microbiology
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• 제34권1호
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• pp.74-81
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• 1996

Two secretion vectors, pUBA240 and pUB340 were constructed by using the promoter and secretory signal region of the .alpha.-amylase gene from an .alpha.-amylase hyperproducing strain, Bacillus subtilis NA64. In this secretion vector system, various restriction enzyme sites are located immediately after the proregion of the .alpha.-amylase gene for easy replacement of various foregn structural genes. To evaluate this secretion vectors, the .betha.-lactamase gene of pBR322 was used as a reporter gene. The expressed and biologically active .betha.-lactamase was secreted into the culture broth from B. subtilis LKS86 transformants harboring each .betha.-lactamase secreting plasmid, pUBAbla and pUBSble. In both cases, more than 92% of expressed .betha.- lactamases were located idn the culture medium. The amount of the secreted .betha.-lactamase was about 80% of the total secreted proteins in the culture medium.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.207-211
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• 2015

In this paper, 2 kinds of models about bike frame are simulated with static structural analysis. A bike frame with diamond type is compared with another model that Down tube is eliminated from original diamond frame. About both types of models, Property of a material and conditions of restriction & load are the same. This study shows reinforcement effects of a partial frame by adding down tube and impacts generated by applying a load at the frame such as weak points & high stress parts as well as expected deformation. The structural result of this study indicates that the equivalent stress or total deformation decreases by 57.1% or 36.4%, respectively. Also stress concentration sites are leg connecting parts, front/rear wheels fixed region and Max deformation is generated from Seat tube. In conclusion, A Down tube is highly efficient as reinforcement than frame without non down tube. Furthermore, The safety rises in case of reducing top tube thickness and increasing a reinforcement at leg connecting parts or concentration regions.

• Mycobiology
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• 제37권3호
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• pp.240-242
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• 2009

An improved procedure for preparing PCR cloning vectors was developed. This procedure includes the incorporation of adapters to create XcmI restriction enzyme sites in pBluescript II SK(+) vectors, digestion with XcmI followed by further digestion of the small fragment produced by XcmI digestion with additional enzymes, and purification with PCR purification kits. Using this procedure, PCR cloning vectors with high ligation efficiencies and low blue or false-positive colonies were obtained.