• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1997-2003
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• 2004

This paper presents a new method and an associated device, capable of detecting protein presence and size from the shift of the mechanical stiffness changing points due to the presence and size of proteins in a nano-gap actuator. Compared to the conventional resonant detection method, the present nanomechanical stiffness detection method shows higher precision for protein detection. The present method also offers simple and inexpensive protein detection devices by removing labeling process and optical components. We design and fabricate the nanomechanical protein detector using an electrothermal actuator with a nano-gap. In the experimental study, we measure the stiffness changing points and their coordinate shift from the devices with and without target proteins. The fabricated device detects the protein presence and the protein size of 14.0$\pm$7.4nm based on the coordinate shift of stiffness changing points. We experimentally verify the protein presence and size detection capability of the nanomechanical protein detector for applications to high-precision biomolecule detection.

• Journal of Life Science
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• v.23 no.2
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• pp.299-305
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• 2013

Paenibacillus is a gram-positive, spore-forming aerobes that was previously classified as a Bacillus species. Paenibacillus sp. CK214 was highly motile on LB agar plates and showed typical colonial morphology of Paenibacillus. However, its motility was defective in the absence of glucose. Electron microscopic observation revealed that the cells of CK214 cultured on LB agar plates were peritrichously flagellated but not flagellated in the presence of glucose. Flagellar filaments were purified by centrifugation after shearing off from the CK214 cells with vigorous pipetting. The purified protein was composed of a single flagellin with an apparent molecular size of 29 kDa. Recognition of the protein by anti-Edwardsiella tarda flagellin protein antibody demonstrates that the protein is a flagellin protein. A decreased level of flagellin protein was detected in CK214 cells grown under glucose-supplemented media.

• Journal of Conservation Science
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• v.12 no.1 s.15
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• pp.83-91
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• 2003

The paste used for conserving and mounting has much to do with the life of cultural properties of paintings. Previous studies on the pastes dealt with elimination of protein from wheat flour as protein has been known to do harm to paste and investigated the effects of starch and protein content on adhesive strength and conservativeness. We found that protein content inversely affected adhesive strength while adhesive strength and viscosity of paste were proportionally related to starch concentration of the paste. The adhesives with more protein showed less conservativeness. Types and number of microorganisms were found to increase as protein percentage increased. All these results points that the higher content of protein in adhesive formula support higher microbial growth with reduced adhesive strength, but higher flexibility. The optimized paste of conservation treatment was wheat starch paste with not only minimize viscosity but also maximized adhesive strength.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.769-773
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• 2001

Protein content of okara and soybean were found to be 37.3% and 42.5%, respectively by micro-Kjeldahl analysis. Solubility of okara protein in phosphate buffer (pH 8) was 10% versus soy protein of 68.4%. Insolubilization of okara protein was mostly due to disulfide bonding between cysteine residues caused by excessive heat treatment during soymilk processing: hydrophobic interactions and hydrogen bondings were involved to lesser extent. Optimum extraction temperature and time were $60^{\circ}C$ and 40 min. Typical solubility profile of soy protein disappeared for okara protein though minimum solubility of the protein was around pH 3.0. Treating okara with protease was effective in solubilizing okara protein and solubility increased to 19.2%. Optimum reaction temperature and time were $80^{\circ}C$ and 50 min, respectively. Cell wall degrading enzyme did not increase solubility of the protein, however. Through enzymatic reaction okara protein could be effectively solubilized for uses as food ingredient.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.84-85
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• 2012

Poly(ethylene glycol) (PEG)는 Hydrophilic하면서 독성이 없기 때문에 약물과 관련된 연구가 많이 이루어졌다. 초기 PEGylation은 약물과 관련된 연구가 주를 이루었지만, 최근에는 PEG의 non-fouling 효과 때문에 표면에 적용하여 biomedical 장비에 세포나 단백질이 붙지 않도록 하는 개질하는 방법에 많은 연구가 진행되고 있다. Native Chemical Ligation(N.C.L.)은 단백질을 합성할 때, Protecting group을 사용하지 않고 반응을 진행시킬 수 있기 때문에 많은 주목을 받고 있다. N.C.L.은 합성한 두 물질이 Thioester와 Cysteine을 갖고 있으면, mild condition에서 amide bond를 형성하면서 반응이 쉽게 진행되기 때문에 다양한 분야에 적용할 수 있다. 이 논문에서 우리는 N.C.L.을 표면에 적용시켰으며 그 중 한 예로 표면 PEGylation진행하였다.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.1
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• pp.51-58
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• 1996

The effects of allylisothiocyanate on the biosynthesis of various fungus metabolites such as sterigmatocystin, lipid, protein, citrate RNA and AMP from the culture of Aspergillus Parasiticus R-716 were investigated. The content of sterigmatocystin, the precursor of aflatoxin, was lower in the culture added with 50ppm allylisothicoyanate after 48 hours, however was rather higher after 144 hours compared to that of the control. The addition of allylisothiocyanate resulted in the increase of lipid, protein, RNA in mycelium and the content of citrate in the media, but the amount of AMP was low.

• The Korean Journal of Zoology
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• v.35 no.3
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• pp.287-294
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• 1992

배양 중의 골격근 세포는 증식을 거쳐 세포융합을 통해 다핵세포로 분화되므로 세포분화의 연구에 좋은 모델로서 이용되고 있다. 이전 실험에서 근원세포 융합을 억제하는 단일클론항체(MII-3J31)가 제작되었으며(Kim et al., 1992)이 항체에 대한 항원은 분자량이 약 35 kDa인 세포막 단백질로 추정되었다. 본 실험에서는 13일 계배와 성체의 근섬유 mRNA에서 CDNA라이브러리를 제작하여 근원세포 분화에 특이적으로 나타나는 유전자를 추적하였다. 근원세포 융합에 관여하는 단백질에 대한 CDNA는 계배 13일 째의 근원세포 CDNA라이브러리에서 단일클론항체를 사용한 immunoscreening 방법을 이용하여 확인하였다. 이 CDNA의 크기는 약 1.5 kb였다. 한편 13일 계배와성체 근섬유 CDNA 라이브러 리를 이용하여 13일 계배에만 특이하게 유전자 발현 이 일어 나고 성체에서는 나타나지 않는 약 0.8 kb의 CDNA플 찾았다.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.714-720
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• 1989

Effects of acetylation on conformational changes of glycinin was studied using solvent perturbation, second derivative spectroscopy, near uv circular dichroism spectra and viscosity. Glycinin with purity of more than 93% was used for the experiment. Modification was carried out with acetic anhydride and glycinin with lysine residue modification of 0%, 28%, 65%, 85%, and 95% were used for the experiment. The result of solvent perturbation using some selected perturbants, such as glycerol, ethylene glycol, and dimethyl sulfoxide revealed that acetylation has caused increase In solvent accessibility of tyrosine residues from less than 40% in native protein to more than 70% for 95% acetylated glycinin. This was confirmed by second derivative spectroscopy. Near ultraviolet circular dichroism revealed that the spectra of native and acetylated glycinin were almost identical differing only in intensity and no other useful information could be derived from it. However, in the case of 95% acetylated glycinin the influence of tryptophan on the spectrum was more pronounced Specific viscosity of glycinin also increased by modification, the extent of which depended upon the degree of acetylation. These results supported that acetylation had caused globular conformation of glycinin to be expanded and denatured.

• 한국문화재보존과학회:학술대회논문집
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• 2003.09a
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• pp.79-80
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• 2003

• Proceedings of the Korean Society of Crop Science Conference
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• 1993.10a
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• pp.44-45
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• 1993