• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.285-289
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• 1994

An insecticidal crystal protein gene, cryIA(c), from Bacillus thuringiensis HD-73 was integrated into the chromosome of a xanthan-producing bacterium, Xanthomonas campestris XP92. The cryIA(c) gene expression cassette was constructed that placed the gene between the trc promoter and rrnB transcriptional terminator. The $lacl^q$ gene was also included to prevent the expression of cryIA(c) gene in X campestris cells. Southem blot analysis confirmed the integration of the cryIA(c) gene expression cassette in chromosome of X campestris XP92 transconjugant. Expression of the insecticidal crystal protein was confirmed by Western blot analysis and bioassay against the larvae of Hyphantria cunea (Lepidoptera： Arctiidae) and Plutella xylostella (Lepidoptera：Plutellidae).

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.6
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• pp.367-370
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• 2002

Candida cylindracea lipase was immobilized by adsorption on acid washed glass beads. It was observed that protein loading of the support depends on the size of the particle, with smaller particle containing higher amount of protein per unit weight. Initial reaction rate linearly varied up to enzyme concentration of 17.25 U/mL. Amount of free fatty acids produced was linearly proportional up to the enzyme loading of 1650 $\mu$g/g of bead. Achievement of chemical equilibrium took longer time in the case of less protein loading. Degree of hydrolysis was found to decrease in second and third consecutive batch operations on repeated use of immobilized lipase.

• Macromolecular Research
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• v.11 no.4
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• pp.241-249
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• 2003

A molecular-thermodynamic model to describe the salt-induced protein precipitation is developed based on the perturbation theory. We employed the modified perturbed hard-sphere-chain (PHSC) equation of state for copolymer mixtures to take into account the pre-aggregation effect among protein particles. Hypothetical pressure-composition diagrams are computed with various size differences and salt concentrations. The precipitation behaviors are also studied for various types of pre-aggregation effect for the given systems.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.213-213
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• 2001

• ETRI Journal
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• v.37 no.4
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• pp.813-823
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• 2015

Because protein is a primary element responsible for biological or biochemical roles in living bodies, protein function is the core and basis information for biomedical studies. However, recent advances in bio technologies have created an explosive increase in the amount of published literature; therefore, biomedical researchers have a hard time finding needed protein function information. In this paper, a classification system for biomedical literature providing protein function evidence is proposed. Note that, despite our best efforts, we have been unable to find previous studies on the proposed issue. To classify papers based on protein function evidence, we should consider whether the main claim of a paper is to assert a protein function. We, therefore, propose two novel features - protein and assertion. Our experimental results show a classification performance with 71.89% precision, 90.0% recall, and a 79.94% F-measure. In addition, to verify the usefulness of the proposed classification system, two case study applications are investigated - information retrieval for protein function and automatic summarization for protein function text. It is shown that the proposed classification system can be successfully applied to these applications.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.344-347
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• 2003

Unnatural amino acid S-(2-nitrobenzyl)cysteine was incorporated into human erythropoietin by using a programmed suppression of nonsense codon in a cell-free protein synthesis system. Several controlling factors affecting the operational efficiency of the suppression were investigated and optimized. The amount of suppressor tRNA and the concentration of $Mg^2+$ were crucial not only for the efficiency but also for the control of the exact suppression. In addition, some general optimization factor are reported in order to improve the efficiency in an unnatural amino acid mutagenesis.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.299-299
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• 2005

• BMB Reports
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• v.28 no.2
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• pp.149-154
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• 1995

Protein methylase II (S-adenosyl-L-methionine : protein O-methyl-transferase, EC 2.1.1.24; PM II) was purified approximately 1250-fold from porcine testis by fractional precipitation and DEAE-cellulose chromatography, followed by gel filtration on a Sephadex G-75 column and HPLC on a Protein Pak 125 column. The molecular weight of the enzyme was estimated to be 33,000 daltons by SDS-PAGE, which agreed with the value determined by gel filtration. Isoelectric focusing of purified PM II showed a single protein species with an isoelectric point of 6.2. The optimum pH for the reaction was 6.0. The $K_m$ value of the enzyme was $1{\times}10^{-5}M$ with a $V_{max}$ value of 769 pmol/min/mg of enzyme. S-adenosyl-L-homocysteine is a competitive inhibitor of PM II with a $K_i$ value of $1.38{\times}10^{-6}M$.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.538-544
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• 2008

Activated protein C (APC) is thought to exert antiinflammatory activities through the endothelial protein C receptor (EPCR)-dependent cleavage of protease activated receptor 1 (PAR-1) in endothelial cells. Since thrombin cleaves PAR-1 with $\sim$3-4-orders of magnitude higher efficiency, and PAR-1 is a target for proinflammatory activities of thrombin, it is not understood how APC can elicit protective responses through the cleavage of PAR-1. In this study, we demonstrate that EPCR is associated with caveolin-1 in endothelial lipid rafts, but its occupancy by protein C leads to its dissociation from caveolin-1 and subsequent recruitment of PAR-1 to protective signaling pathways through the coupling of PAR-1 to Gi-protein. When EPCR is bound by protein C, the PAR-1-dependent protective response in endothelial cells can be mediated by either thrombin or APC. These results provide a new paradigm for understanding the mechanism through which PAR-1 and EPCR participate in cellular signaling events in endothelial cells.

• Korean Journal of Computational Design and Engineering
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• v.11 no.2
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• pp.97-106
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• 2006

Voronoi diagrams have been known for numerous important applications in science and engineering including CAD/CAM. Especially, the Voronoi diagram for 3D spheres has been known as very useful tool to analyze spatial structural properties of molecules or materials modeled by a set of spherical atoms. In this paper, we present two algorithms, the edge-tracing algorithm and the region-expansion algorithm, for constructing the Voronoi diagram of 3D spheres and applications to protein structure analysis. The basic scheme of the edge-tracing algorithm is to follow Voronoi edges until the construction is completed in O(mn) time in the worst-case, where m and n are the numbers of edges and spheres, respectively. On the other hand, the region-expansion algorithm constructs the desired Voronoi diagram by expanding Voronoi regions for one sphere after another via a series of topology operations, starting from the ordinary Voronoi diagram for the centers of spheres. It turns out that the region-expansion algorithm also has the worst-case time complexity of O(mn). The Voronoi diagram for 3D spheres can play key roles in various analyses of protein structures such as the pocket recognition, molecular surface construction, and protein-protein interaction interface construction.