• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.363-369
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• 2003

Selenized yeast (Se yeast) containing $0.1{\%}$(w/w) of selenium was obtained when the yeast was incubated at a selenium concentration of 1$1.14{\times}10_-3 M$ in rich medium. After washing several times, the inorganic selenium on the cell wall was confirmed with MBRT. There was no indication of inorganic selenium on the cell wall when the blue color in MBRT was stayed for 15 minutes. The selenized yeast was sonicated, then the selenium contained protein was obtained after salting out by ammonium sulfate at the concentration $80{\%}$ saturation. The seven protein bands were seperated by SDS-PAGE and the selenium concentration in protein was measured by ICP-AES. Analytical data showed that the large expressed protein band contained a relatively large amount of selenium. The proteins of the 47kDa was contained the concentrations of 69.5 ${\mu}$ Se/g of most many content. The protein (47 kDa) was seperated from PVDF membrane by tank-electroblotting. The isolated protein was hydrolyzed under acid condition and reacted with PITC. The derivatives of amino acids were analyzed by HPLC and compared with the data obtained from regular yeast. The resulting selenium-yeast was analyzed with the selenomethionine concentration of $2{\%}$ comparaed with general amino acids. The goal of this study is to analyze the selenium concentration in protein bands and measure the degree of biotransformation of selenomethionine in a specific protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.3
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• pp.502-508
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• 1994

A total of 24 specimens of the pufferfish, Fugu xanthopterus, purchased at a fixhmarket in Pusan, korea were examined for toxicity using the assay method of tetrodotoxin (TTX). Also, the toxins isolated from the puffer liver were partially purified and analyzed for their chemical composition by instrumental behaviors. On the whole, when the level of toxicity in each organ was analyzed compared to that of liver, they were 100 % of the lover, 92 % for the intestine, 75% for the skin, 17% for the muscle, 785 for the testis, 87% for the ovary, and 71% for bile. The highest and average scores of toxicity for the liver were 917 and $231{\pm}51MU/g$ liver, respectively. The toxins of the puffer gave four peaks in HPLC whose retention times (10, 20, 22 and 25 min) were close to those of TDA, TTX, 4-epi-TTX, and and -TTX, respectively.

• Journal of KIISE:Software and Applications
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• v.30 no.5_6
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• pp.398-413
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• 2003

Component-based Software Development(CBSD) supported by both component and reusability can reduce development time and cost, and also can achieve high productivity. To support component reusability systematically domain analysis and design in parallel with CBSD-process is needed. And also it is needed to suggest objective analysis process to fine out commonality and variability in domain, which is lacked in current domain analysis and design method. And to abstract domain component from the information which is well reflected in domain model, and to express it in domain architecture is needed. In this paper, we suggest the method to define, analyze and design domain systematically for enhancing reusability effectively in Component-base Software Development. We abstract components which can be reusable in domain, in other word, which have commonality from requirement analysis level. We sustain and refine them. And we reflect them to the products of each level. From these process, we can produce the domain component which have commonality. On this basis, we can design domain architecture. In this paper, to produce reusable software we investigate new systematic approach to domain analysis and design from the view point of software reusability.

• Research in Plant Disease
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• v.9 no.3
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• pp.107-115
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• 2003

Chinese yam (Dioscorea opposita cv. Jang-Ma) plants showing necrotic mosaic symptom were collected from their growing fields in Andong, Euisong, Gunwi and Daegu, Korea. Direct negative stainning method by electron microscope showed filamentous particles of about 660 nm in length. Immunosorbent electron microscopy (ISEM) revealed filamentous particles of 660nm decorated with antiserum of Chinese yam necrotic mosaic virus (ChYNMV). The virues purified partially were used to isolate viral RNA as template for RT-PCR to amplify about 1.2 kbp of 3'-terminal region (coat protein, 3'-UTR) with ChYNMV specific and oligo-dT primers. Amino acids sequences of amplified CP genes revealed that the viruses shared 97.9% similarity with ChYNMV (AB044386) wh ich was known as the member of Macluravirus. So the viruses from Chinese yam (D. opposita cv. Jang-Ma) plants were identified as ChYNMV. Comparing the CP amion acid sequences of ChYNMV strains with other macluraviruses such as Cardamon mosaic virus (CdMV), Narcissus latent virus (NLV) and Maclura mosaic virus (MacMV) revealed that N-terminal was the most varialbe region and conserved regions were present within the genus Macluravirus.

• KSBB Journal
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• v.22 no.1
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• pp.16-21
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• 2007

Although Energy demands of modern society increase rapidly, current energy would be exhausted shortly. Therefore development of bio-ethanol production process from cellulose containing materials was extremly demanded. Therefore development of highly functional cellulase is requisite for this purpose. In this study cellobio-hydrolase (CBH1) gene from Trichorderma reesei was used to increase cellulase activity by directed evolution and highly functional cellobio-hydrolase was obtained and characterized.

• Journal of Life Science
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• v.26 no.3
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• pp.353-358
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• 2016

Thiolase is an enzyme that catalyzes condensation reactions between two acetyl-CoA molecules to produce acetoacetyl-CoA. As thiolase catalyzes is the first reaction in the production of n-butanol, knowledge of the molecular and regulatory mechanism of the enzyme is crucial for synthesizing high-value biofuel. Thiolase from Clostridium butyricum (CbTHL) was expressed, purified, and crystallized. X-ray diffraction data were collected from the crystals, and the 3-dimentional structure of the enzyme was determined at 2.0 Å. The overall structure of thiolase was similar to that of type II biosynthetic thiolases, such as thiolase from C. acetobutylicum (CaTHL). The superposition of this structure with that of CaTHL complexed with CoA revealed the residues that comprise the catalytic and substrate binding sites of CbTHL. The catalytic site of CbTHL contains three conserved residues, Cys88, His349, and Cys379, which may function as a covalent nucleophile, general base, and second nucleophile, respectively. For substrate binding, the way in which CbTHL stabilized the ADP moiety of CoA was unlike that of other thiolases, whereas the stabilization of β-mercaptoethyamine and pantothenic acid moieties of CoA was quite similar to that of other enzymes. The most interesting observation in the CbTHL structure was that the enzyme was regulated through redox-switch modulation, using a reversible disulfide bond.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.378-383
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• 1999

Changes of the spectroscopic characteristics of the organic matter fractions and circular filter paper chromatograph were assessed for the bark and piggery manure composts during the composting. as an approach to base the criteria of the compost maturity evaluation. Contents of humic acid-C (HA-C) and fulvic acid-C (FA-C) in both bark and piggery manure composts were decreased as the composting got closer to maturity, but the ratios of HA-C/FA-C were increased. During the composting. ${\Delta}log$ K values were decreased, but RF values were increased. Humic acid of the mature bark compost after 120 days of composting was A-type, as compared to Rp-type for the raw bark and B-type for the immature compost. However. humic acid of the mature piggery manure composts after 40 days of composting was B-type, indicating the humification of the organic matter fractions continued at this stage. Circular filter paper chromatograph of the mature bark compost exhibited the regular sawteeth pattern at the edge, but that of the mature piggery manure showed an irregular sawteeth pattern. Results demonstrated that spectroscopic characteristics and circular filter paper chromatograph of the organic by-product composts might be employed for the compost stability assessment.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.257-264
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• 1983

In order to obtain more specific antigenic preparation for the diagnosis of human paragonlmiasis, crude saline extract of whole worm (=PwWWE), secretory.excretory components (PwSEC) and secretion-excretion-free somatic extract (PwSM) of 12 week-old ParagoninBus westermani were filtrated through Sephadex G-200 gel column. The adult Paragonimus worms were obtained from expevimentally infected doge. A total of 11 antigenic solutions was Iyophilised or diluted to adjust protein content of 1mg/ml. To evaluate the antigenicity of crude antigens and fractions, micro-ELISA was done with the sera from P westermani in(ected cases, C. sinensis infected cases and non-infected control cases to detect Paragonimus specific IgG antibody. The results were as follows: 1. When the PwWWE was filtrated through Sephadex G-200 gel, it was separated into three fractions; PwWWE Fr. 1, PwWWE Fr. 2 and PwWWE Fr. 3. The percentage of protein content was 28.0%, 21.6% and 50.4% respectively. The PwSM was also. separated into three fractions; PwSM Fr. 1, PwSM Fr. 2, PwSM Fr. 3. and their percentage of protein content was 41.3%, 38.6% and 20.1%. However, the PwSEC showed different fractionation pattern; i.e. fraction 1 (=PwSEC Fr.1) and 3 (PwSEC Fr. 3) without fraction 2. The percentage of protein content was 14.0% in PwSEC Fr. 1 and 86.0% in PwSEC Fr. 3. 2. When the antigenicity of each Paragonimus crude antigen and fractionated antigen was evaluated for specific IgG aritibody by micro-ELISA in 10 human paragonimiasis sera, PwSEC Fr, 1 was the most potent antigen showing the mean absorbance 1.98. The PwWWE Fr. 1, PwSEC, PwWWE were next to that: their mean absorbance were 1.72, 1.38 and 0.83 respectively. The antigenicity of fractions 2 and 3 was much weaker in binding specific IgG antibody. 3. When the antigens were reacted in micro-ELISA with 10 human clonorchiasis sera, most antigens showed weak reactivity. Each fraction 1 of crude antigens reacted higher than other fractions or crude antigens; the mean absorbance was 0.17 in fraction 1, but in others the absorbances were about 0.06. 4. With non-infected control sera, the result of micro-RLISA revealed almost same pattern with those of the clonorchiasis sera. From the above results, it became apparent that PwWWE Fr. 1, especially PwSEC Fr. 1 was the most potent antigen reacted with Paragonisfaus specific IgG antibody.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.215-221
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• 1994

The complete nucleotide sequence of the cloned pga gene encoding the penicillin G acylase of Bacillus megaterium ATCC 14945 and its 5'- and 3'-flanking regions was determined. The sequence revealed only one large open reading frame (2,406 hp) of the penicillin G acylase (pga) gene. Upstream from ATG of the pga gene, there was a putative ribosome binding site, Shine-Dalgarno sequence. The promoter-like structure, - 10 and - 35 sequences, was also found. Following the stop codon, TAG, a structure reminiscent of the E. coli rho-independent transcription terminator was present. The amino acid sequence was deduced from the nucleotide sequence. The molecular mass of the polypeptide was 91,983 Da. There was a potential signal sequence in its amino-terminal region. A comparison of its deduced amino acid sequence with other characterized penicillin G acylases and the result of SDS-polyacrylamide gel electrophoresis of the purified enzyme showed that a precursor polypeptide of 92 kDa was processed into two dissimilar ${\alpha}$ and ${\beta}$-subunits of 25 and 61 kDa.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.556-561
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• 1997

Vibrio cholerae non-O1 FM-3 was isolated from sea water, and it showed the same bacteriological characteristics as Vibrio cholerae non-O1 ATCC 25872. V. cholerae non-O1 FM-3 presented the highest hemolytic activity at stationary phase of its growth. The hemolytic activity was decreased in accordance with increasing of pretense activity of its cultural supernatant. The characteristics of the hemolysin produced by V. cholerae non-O1 FM-3 were investigated after partial purification with a Sephadex G-100 chromatography. The hemolytic activity of purified protein was stable at $4^{\circ}C$ while it was completely lost by heating at $60^{\circ}C$ for 30 min. The activity of hemolysin was increased by addition of divalent cations such as $Ca^{2+},\;Mg^{2+},\;and\;Mn^{2+}$ while it was inhibited by additions of $Zn^{2+}$. When the hemolysin was incubated with suspensions of erythrocytes at $4^{\circ}C$ and $37^{\circ}C$, respectively, hemolysis was not observed at $4^{\circ}C$ but at $37^{\circ}C$. It means that hemolysis by purified hemolysin was temperature-dependent while its binding step of hemolysin to cell membrane was temperature-independent.