• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.213-215
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• 2010

• Journal of Microbiology
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• v.38 no.1
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• pp.11-17
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• 2000

A new method was developed for the rapid analysis of diverse bacterial species in the natural environment. Our method is based on PCR-single-strands-conformation polymorphism (PCR-SSCP) and selective isolation technique of single-stranded DNA. Variable V3 fragments of 16S rDNA were amplified by PCR with bacterial 16S rDNA primers, where one of the primers was biotinylated at the 5'-end. The biotinylated strands of the PCR products were selectively isolated by using streptavidin paramagnetic particles and a magnetic stand, to prevent SSCP analysis producing heteroduplexes from heterogeneous DNA samples. The selected strands were separated by electrophoresis on a polyacrylamide gel, and detected by silver staining. Analysis of PCR products from 8 bacterial strains demonstrated their characteristic DNA band patterns. In addition, changes in the structure of the bacterial community and species diversity in the microcosm treated with phenol could be monitored. After 3 weeks of incubation, phenol and its intermediate, 2-hydroxy-muconic-semialdehyde, were degraded by indigenous bacteria. These dominating bacterial populations were identified as strong bands on an SSCP gel. Therefore, this study provides useful tools for microbial community analysis of natural habitats.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.2004-2007
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• 2006

An efficient method for the in vitro reassembly of homologous DNA sequences is presented. The proposed method involves obtaining single strands of homologous genes and hybridizing them to obtain partially hybridized heteroduplex DNA; cleaving the single-stranded regions of the heteroduplex DNA using S1 nuclease to generate double-strand DNA fragments; denaturing the double-strand DNA fragments to generate single-strand DNA fragments; conducting a series of polymerase chain reactions (PCR) using the single-strand DNA fragments as internal primers and a mixture of homologous DNA as templates to obtain elongated reassembled DNA; and finally, amplifying the reassembled DNA by a PCR using terminal primers. As a result, DNA reassembly could be achieved between homologous genes with a sequence similarity as low as 78%.

• BMB Reports
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• v.37 no.4
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• pp.439-444
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• 2004

Double stranded targets on the cDNA microarray contain representatives of both the coding and noncoding strands, which will introduce hybridization competition with probes. Here, the effect of double and single strands of targets on the signal intensity and the ratios of Cy5/Cy3 within the same slide were compared. The results show that single stranded targets can increase the hybridization efficiency without changing the Cy5/Cy3 ratio. Based on these results, a new strategy was established by generating cDNA targets with asymmetric PCR, instead of conventional PCR, to increase the sensitivity of the cDNA microarray. Furthermore, the feasibility of this approach was validated. The results indicate that the cDNA microarray system based on asymmetric PCR is more sensitive, with no decrease in the reliability and reproducibility as compared with that based on conventional symmetric PCR.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.11
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• pp.2500-2504
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• 2011

Living organisms are composed of cells that can replicate themselves through growth, division packed with tons capacity. On DNA mutations, ie mutations in the offspring's survival and reproduction can be held against you, and packed with tons ambivalence that could benefit. In this study, the DNA double helix is used as a template for replication, we first separated into single strands of the double helix must be opened Combining the double helix portion of the location of errors in the bond provides a way to find and repair.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.320-326
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• 2008

In this paper, we propose a new algorithm emulating the DNA characteristics for noise-tolerant pattern matching problem on digital system. The digital pattern matching becomes core technology in various fields, such as, robot vision, remote sensing, character recognition, and medical diagnosis in particular. As the properties of natural DNA strands allow hybridization with a certain portion of incompatible base pairs, DNA-inspired data structure and computation technique can be adopted to bio-signal pattern classification problems which often contain imprecise data patterns. The key feature of noise-tolerance of DNA computing comes from control of reaction temperature. Our hardware system mimics such property to diagnose cardiovascular disease and results superior classification performance over existing supervised learning pattern matching algorithms. The hardware design employing parallel architecture is also very efficient in time and area.

• YAKHAK HOEJI
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• v.40 no.4
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• pp.442-448
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• 1996

Mitomycin C(MMC) has been used as an anticancer drug and behaves as an alkylating agent forming covalent cross-link between complementary strands of double strand DNA. The purpose of this research was to determine number of DNA adducts, formed in vivo by Mitomycin C, in mouse organs. DNAs from liver, lung, brain and pancreas were isolated and used for $^{32}P$-postlabelling. The labeled nucleotides were separated by 2D-TLC and subjected to autoradiography. Numbers of MMC-DNA adducts were 9,9,5,4 in liver, pancreas, lung and brain, respectively.

• Journal of Yeungnam Medical Science
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• v.19 no.1
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• pp.1-10
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• 2002

With the establishment of rapid sequence analysis of 16S rRNA and the recognition of its potential to determine the phylogenetic position of any prokaryotic organism, the role of 16S rRNA similarities in the present species definition in bacteriology need to be clarified. Comparative studies clearly reveal the limitations of the sequence analysis of this conserved gene and gene product in the determination of relationship at the pathogenic strain level for which DNA-DNA reassociation experiments still constitute the superior method. Since today the primary structure of 16S rRNA is easier to determine than hybridization between DNA strands, the strength of the sequence analysis is to recognize the level at which DNA pairing studies need to be performed, which certainly applies to similarities of 97% and higher.

• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.453-475
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• 1998

During the 100 years since the initial discovery of meiotic phenomenon many brilliant aspects have been elucidated, but further researches based on light microscopy alone as an experimental tool have been found to have some limits and shortcomings. By the use of electron microscopy and armed with the advanced knowledges on modern genetics and biochemistry it has been possible to applu molecular technology in gaining information on the detailed aspects of meiosis. As synapsis takes place, a three-layered proteinous structure called the synatonemal complex starts to form in the space between the homologous chromosomes. To be more precise, it begins to form along the paired chromosomes early in the prophase I of meiotic division. The mechanism that leads to precise point-by-point pairing between homologous chromocomes division. The mechamism that leads to precise point-by-point pairing between homologous chromosomes remains to be ascertained. Several items of information, however, suggest that chromsome alignment leading to synapsis may be mediated somehow by the nuclear membrane. Pachytene bivalents in eukaryotes are firmly attached to the inner niclear membrane at both termini. This attached begins with unpaired leptotene chromosomes that already have developed a lateral element. Once attached, the loptotene chromosomes begin to synapse. A number of different models have been proposed to account for genetic recombination via exchange between DNA strands following their breakage and subsequent reunion in new arrangement. One of the models accounting for molecular recombination leading to chromatid exchange and chiasma formation was first proposed in 1964 by Holliday, and 30 years later still a modified version of his model is favored. Nicks are made by endomuclease at corresponding sites on one strant of each DNA duplex in nonsister chromatid of a bivalent during prophase 1 of meiosis. The nicked strands loop-out and two strands reassociate into an exchanged arrangement, which is sealed by ligase. The remaining intact strand of each duplex is nicked at a site opposite the cross-over, and the exposed ends are digested by exonuclease action. Considerable progress has been made in recent years in the effort to define the molecular and organization features of the centromere region in the yeast chromosome. Centromere core region of the DNA duplex is flanked by 15 densely packed nucleosomes on ons side and by 3 packed nucleosomes on the other side, that is, 2000 bp on one side and 400 400 bp in the other side. All the telomeres of a given species share a common DNA sequence. Two ends of each chromosome are virtually identical. At the end of each chromosome there exist two kinds of DNA sequence" simple telpmeric sequences and telpmere-associated sequencies. Various studies of telomere replication, function, and behabior are now in progress, all greatly aided by molecular methods. During nuclear division in mitosis as well as in meiosis, the nucleili disappear by the time of metaphase and reappear during nuclear reorganizations in telophase. When telophase begins, small nucleoli form at the NOR of each nucleolar-organizing chromosome, enlarge, and fuse to form one or more large nucleoli. Nucleolus is a special structure attached top a specific nucleolar-organizing region located at a specific site of a particular chromosome. The nucleolus is a vertical factory for the synthesis of rRNAs and the assenbly of ribosome subunit precursors.sors.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.539-542
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• 2002

We propose new encoding method for numerical data in DNA using temperature gradient. To represent numerical values in DNA sequences, we introduce melting temperature. Since DNA strands representing smaller values have a lower Tm, they tend to denature with ease and also easily amplified by denaturation temperature gradient PCR. We also implement a local search molecular algorithm using temperature gradient, which is contrasted to conventional exhaustive search molecular algorithms. The proposed methods are verified by solving an instance of the travelling salesman problem. We could effectively amplify the correct solutions and the use of temperature gradient made the detection of solutions easier.