• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.889-892
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• 2000

Antisense molecules are structurally simple linear oligomers of nucleotides. They can recognize a complementary sequence by base pairing, therefore, antisense drugs composed of 15-16 bases are potentially useful, unlike drugs such as protein agonists, antagonists, and inhibitors. Since antisense oligomers are classified as nucleotides, they are subject to attack by nucleases. In order to be antisense drugs resistant to degradation by nucleases, the structural modifications in the linkages, bases, and sugars to satisfy this requirement are considerable. We attempted in this study, to synthesize 16-mer antisenses with a modified linkage and adenosine. When studying on the three-dimensional structure of the oligomer, however, the existence of isomers may complicate the interpretation of the NMR data. Therefore, an attempt was made to eliminate the above problem, thus, two dimers were synthesized and their structural studies were carried out.

• Journal of Microbiology and Biotechnology
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• 제21권3호
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• pp.274-276
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• 2011

Distinction of Bacillus cereus from other closely related bacilli is challenging and new efficient methods are continually demanded. From our previous work on RAPD profiles of bacilli, we found a possibility that B. cereus strains could be distinguished from other bacilli. In this work, RAPD-PCR profiles of B. cereus strains were obtained using a 10-mer (S30) as a primer, and a B. cereus specific 0.91-kb band was produced from all tested strains. The RAPD-PCR procedure also successfully detected B. cereus from spiked cheonggukjang when B. cereus cells were present at more than $10^2$/g sample.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2006년도 Principles and Practice of Microarray for Biomedical Researchers
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• pp.78-78
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• 2006

Gene expression analysis can be performed by one-color (intensity-based) or two-color (ratio-based) microarray platforms depending on the specific applications and needs of the researcher. The traditional two-color approach is well founded from a historical and scientific standpoint, and the one-color approach, when paired with high quality microarrays and a robust workflow, offers additional flexibility in experimental design. Two of the major requirements of any microarray platform are system reproducibility, which provides the means for high confidence experiments and accurate comparison across multiple samples; and high sensitivity, for the detection of significant gene expression changes, including small fold changes across multiple gene sets. Each of these requirements is fulfilled by the Agilent One-color Gene Expression Platform as illustrated by the data included in this study. As a result, researchers have the ability to take advantage of the enhanced performance and sensitivity of Agilent's 60-mer oligonucleotide microarrays, and experience the first commercial microarray platform compatible with both one- and two-color detection.

• BMB Reports
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• 제37권2호
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• pp.148-152
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• 2004

A new molecular-baiting method was studied by retrieving targeted gene fragments from an oligonucleotide microarray bait after hybridization. To make the microarray bait, 70-mer oligonucleotides that were designed to specifically represent the SSA1 gene of Saccharomyces cerevisiae were printed on the slide. Samples of the Saccharomyces cerevisiae mRNA were extracted and labeled by the RD-PCR (Restriction Display PCR) method using the Cy5-labelled universal primer, then applied for hybridization. The sample fragments that hybridized to the microarray were stripped, and the eluted cDNAs were retrieved and cloned into the pMD 18-T vector for transformation, plasmid preparation, and sequencing. BLAST searching of the GenBank database identified the retrieved fragments as being identical to the SSA1 gene (from 2057-2541bp). A new method is being established that can retrieve the sample fragments using an oligo-microarray-bait.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2268-2273
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• 2008

The drying model has been used to obtain the fundamental information required to design the heat pump dryer with the simple thermodynamic model. In the model, the input conditions are crucial to obtain the acceptable results. The model includes one-stage heat pump cycle, simple drying process using the drying efficiency. The drying efficiency is defined with the conditions of inlet and outlet in the dryer. The experiment has been carried out in the pilot dryer with one-stage heat pump cycle. Refrigerant 134a is used in the heat pump cycle. In the dryer, some of drying air flows through the heat pump system and the rest of air bypasses the heat pump system and circulates through the drying chamber. Some operating conditions from the pilot dryer are used as input conditions of the model and the results are compared with experimental results for the validation.

• Animal cells and systems
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• 제14권4호
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• pp.351-360
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• 2010

A new species of the Cletopsyllidae belonging to the genus Isocletopsyllus Huys and Lee, 1999 is described from the materials collected from subtidal sandy bottoms at Jeju Island and Ulleung Island, Korea. So far, only two species of the genus Isocletopsyllus, viz. I. tertius (Por, 1964) from Israel and I. quartus (Soyer, 1966) from Banyuls-sur-Mer (France) are recorded, both from the Mediterranean Ocean. The new species can be clearly distinguished from its congeners by the combination of the following characters: (1) female antennule with a large process on the outer margin of first segment, (2) caudal rami with a bulbous proximal inner expansion, and shorter than those of other species (about four times long as wide in the new species), (3) second segment of P1 exopod with a short rod-like inner seta, (4) sexual dimorphism presented in the second endopodal segment of male P2, not in exopod of P4, and (6) female P5 with a very long exopod with very short second outer seta. A table comparing the modifications of swimming legs in the family Cletopsyllidae Huys and Lee, 1999 is presented. This is the first record of this family from Korea.

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3703-3706
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• 2010

Biomolecules specific to explosives can be exploited as chemical sensors. Peptides specific to immobilized dinitrotoluene (DNT) were identified using a phage display library. A derivative of DNT that contained an extended amine group, 4-(2,4-dinitrophenyl)butan-1-amine, was synthesized and immobilized using a self-assembled monolayer surface on gold. Filamentous M13 phages displaying random sequences of 12-mer peptides specific to the immobilized DNT-derivate were isolated from the M13 phage library by biopanning. A common peptide sequence was identified from the isolated phages and the synthesized peptides showed selective binding to DNT. When the peptide was immobilized on a quartz crystal microbalance (QCM) chip, it showed a binding signal to DNT, while toluene barely showed significant binding to the QCM chip. These results demonstrate that peptides screened by biopanning against immobilized DNT can be useful for quick and accurate detection of DNT.

• Journal of Microbiology and Biotechnology
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• 제22권10호
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• pp.1367-1374
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• 2012

Pleurocidin, a 25-mer antimicrobial peptide, has been known to exhibit potent antibacterial activity. To investigate the functional roles in N- and C-terminal regions of pleurocidin on the antibacterial activity, we designed four truncated analogs. The antibacterial susceptibility testing showed that pleurocidin and its analogs exerted antibacterial effect against various bacterial strains and further possessed specific activity patterns corresponding with their hydrophobic scale [pleurocidin > Anal 3 (1-22) > Anal 1 (4-25) > Anal 4 (1-19) > Anal 2 (7-25)]. Fluorescence experiments using 1,6-diphenyl-1,3,5-hexatriene (DPH) and 3,3'-dipropylthiadicarbocyanine iodide [$diSC_3(5)$] indicated that the differences in antibacterial activity of the peptides were caused by its membrane-active mechanisms including membrane disruption and depolarization. Blue shift in tryptophan fluorescence demonstrated that the decrease in net hydrophobicity attenuates the binding affinity of pleurocidin to interact with plasma membrane. Therefore, the present study suggests that hydrophobicity in the N- and C-terminal regions of pleurocidin plays a key role in its antibacterial activity.

• 한국식물병리학회지
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• 제14권2호
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• pp.164-170
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• 1998

This study was carried out to develop DNA probe for specific detection of Erwinia carotovora subsp. carotovora. Universal rice primer (URP, 20 mer) developed from repetitive sequence of rice was applied for producing PCR DNA fingerprints of Erwinis spp. In E. carotovora subsp. carotovora strains, primer URP2F amplyfied polymorphic bands which are distinguisable from other Erwinia spp. A PCR band of 0.6 kb selected from PCr polymorphic bands of E. carotovora subsp. carotovora strains was cloned and evaluated as a diagnostic DNA probe. Among 28 bacterial strains including 22 Erwinia spp, the probe (pECC2F) only hybridized to total DNAs from e. carotovora subsp. carotovora strains and E. carotovora subsp. wasabiae, but sizes of hybridized bands were different between these subspecies, 10.0 kb and 3.5 kb respectively. In dot blot assays using probe pECC2F, as few as 103 colony forming units (CFU) of E. carotovora subsp. carotovora could be detected in a suspension containing about 1$\times$103 CFU of soil bacteria.

• Molecules and Cells
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• 제28권5호
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• pp.473-477
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• 2009

Previously, the 9-mer analog peptides, 9Pbw2 and 9Pbw4, were designed based on a defensin-like peptide, protaetiamycine isolated from Protaetia brevitarsis. In this study, antifungal effects of the analog peptides were investigated. The antifungal susceptibility testing exhibited that 9Pbw4 contained more potent antifungal activities than 9Pbw2. A PI influx assay confirmed the effects of the analog peptides and demonstrated that the peptides exerted their activity by a membrane-active mechanism, in an energy-independent manner. As the noteworthy potency of 9Pbw4, the mechanism(s) of 9Pbw4 were further investigated. The membrane studies, using rhodamine-labeled giant unilamellar vesicle (GUV) and fluorescein isothiocyanate (FITC)-dextran loaded liposome, suggested that the membrane-active mechanism of 9Pbw4 could have originated from the pore-forming action and the radii of pores was presumed to be anywhere from 1.8 nm to 3.3 nm. These results were confirmed by 3D-flow cytometric contour-plot analysis. The present study suggests a potential of 9Pbw4 as a novel antifungal peptide.