• Journal of Microbiology and Biotechnology
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• 제28권3호
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• pp.439-447
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• 2018

The aromatic compound p-hydroxybenzoate (PHBA) is an important material with multiple applications, including as a building block of liquid crystal polymers in chemical industries. The cytochrome P450 (CYP) enzymes are beneficial monooxygenases for the synthesis of chemicals, and CYP53A15 from fungus Cochliobolus lunatus is capable of executing the hydroxylation from benzoate to PHBA. Here, we constructed a system for the bioconversion of benzoate to PHBA in Escherichia coli cells coexpressing CYP53A15 and human NADPH-P450 oxidoreductase (CPR) genes as a redox partner. For suitable coexpression of CYP53A15 and CPR, we originally constructed five plasmids in which we replaced the N-terminal transmembrane region of CYP53A15 with a portion of the N-terminus of various mammalian P450s. PHBA productivity was the greatest when CYP53A15 expression was induced at $20^{\circ}C$ in $2{\times}YT$ medium in host E. coli strain ${\Delta}gcvR$ transformed with an N-terminal transmembrane region of rabbit CYP2C3. By optimizing each reaction condition (reaction temperature, substrate concentration, reaction time, and E. coli cell concentration), we achieved 90% whole-cell conversion of benzoate. Our data demonstrate that the described novel E. coli bioconversion system is a more efficient tool for PHBA production from benzoate than the previously described yeast system.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.253-266
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• 1995

Recently, available interests concerning the biologic significance of the extracellular matrix and proliferating cells associated with periodontal disease has been increased. The distribution or expression of cellular proliferation by PCNA, macrophage detection by ${\alpha}$-l-antichymotrypsin, fibronectin playing a important role in host defence mechanisms indirectly, and transglutaminase that cross linked to fibronectin and stimulate fibrin stabilization were studied in inflammed and healthy gingiva. The excised tissue samples were fixed neutral formalin for 24 hours, embedded with paraffin, sectioned at 4-61lffi in thickness, and immunohistochemically processed by LSAB method. The positive reaction to PCNA was localized in the suprabasal and basal layer of inflammed gingiva and an increasing reactivity was observed than healthy gingiva. ${\alpha}$-I-antichymotrypsin positive cells were localized in the basal layer of inflammed gingiva, and there was no or rare positive cells in healthy gingiva. The positive reaction to fibronectin in inflammed gingiva was more than healthy gingiva,"and shown in the connective tissue subjacent to basement membrane of epithelium and in the periphery of the collagen fiber bundles. The positive cells by transglutaminase in inflammed gingiva were noted in suprabasal, spinous, and keratin layer of epithelium, and slightly increased in the capillaries of connective tissues. But the results of this study demonstrated in vitro reaction. Therefore, the role of PCNA,${\alpha}$-l-antichyrnotrypsin, transglutaminase, fibronectin and coefficient with other growth factor and extracellular matrix were further investigated in vivo.

• Tuberculosis and Respiratory Diseases
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• 제75권5호
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• pp.218-221
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• 2013

This report describes a rare case of a patient with splenic tuberculosis (TB) who developed spontaneous splenic rupture after 10 weeks of antituberculous chemotherapy. The patient responded well to the antituberculous regimen prior to the spontaneous splenic rupture. We considered a paradoxical reaction as a cause of the splenic rupture. The patient underwent splenectomy and continuously received initial antituberculous drugs without change. To the best of our knowledge, this is the first report of spontaneous splenic rupture as a paradoxical reaction to antituberculous chemotherapy in an immunocompetent host with splenic TB.

• The Plant Pathology Journal
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• 제15권4호
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• pp.247-250
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• 1999

Wasabies showing mosaic symptoms were collected and extracted for virus purification. Tobacco mosaic virus (TMV) was identified as causal agent by electron microscopy and nucleic acid and coat protein analyses. TMV strains were determined by enzyme-linked immunosorbent assay (ELISA). TMV was identified as W and C strain in wasabi. The results of host reaction indicated that this virus induced local lesions on Nicotiana tabacum cv. Bright Yellow and N. glutinosa, leaf spots on Chenopodium amaranticolor and mosaic symptoms on wasabi. Rot shape virus particles were observed and was about 300 nm in length. About 6.5 kb single RNA molecule was observed from extracted viral RNA sample and 26 KDa coat protein was detected in denatured acrylamide gel. Infection ratio of TMV was 8% for the first cultivation year, but was 22% for the second year when TMV-W antiserum was used. The results of this experiment showed that infection ratios of both TMV-W and TMV-C strains were higher compared to that of TMV-P strain.

• 한국전기전자재료학회논문지
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• 제21권12호
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• pp.1057-1062
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• 2008

The ${\alpha}-In_2S_3:Co^{2+}$ single crystal with a good quality and stabilized property were gained successfully by the CTR(Chemical Transport Reaction)method. XRD analysis showed that the grown single crystals were cubic structure. The optical absorption spectra of ${\alpha}-In_2S_3:Co^{2+}$ single crystal showed impurity absorption peaks due to cobalt impurity. These impurity absorption pesks were assigned to the ligand transition between the split energy levels of $Co^{2+}$ ions sited in $T_d$ symmetry of these semiconductor host lattice.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.529.1-529
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• 1986

For isolation of the CMCase gene of the alkalophilic Bacillus sp. strain N-4 to analyze their genetic information for the multicomponents of the cellulase, Bscherichia coli K12 and plasmid DNA pBR322 was used as host-vector system. After the digestion of purified chromosomal DNA and plasmid DNA pBR322 with HindIII, these were ligated. The ligated DND were transformed into Escherichia coli, and recombinant plasmid 107 carried the gene coding for CMCase was constructed. The CMCase produced by Escherichia coli cells containing plasmid DNA pYBC107 was found in the cells as intracellular enzyme and nearly 60% of the total CMCase activity was localized in cellular fraction. Also, the optimum pH for the reaction of CMCase produced by Escherichia coli was appeared at pH .8.0 and the enzyme was stable between pH 7.0 and pH 8.0.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.784-788
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• 1995

The lambda Integrase (Int) carries out site-specific recombination between the two partner DNA sequences, attachment P (attP) and attachment B (attB). In order to study the recombination mechanism, a large quantity of pure integrase is required. Then, we constructed an int gene inserted recombinant plasmid (pNYL3) by using the pQE31 HIS-Tag vector, and produced the fusion protein, 6xHIS-Int from the E. coli TG1 strain carrying the pNYL3 plasmid. The recombinant protein produced was purified by phosphocellulose and Ni$^{++}$-NTA affinity column chromatographies. The result of the in vitro recombination assay using the standard reaction mixture containing 6xHIS-Int and partially purified integration host factor (IHF) showed that the 6xHIS-Int tagged recombination Integrase had the full recombination activity.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1505-1512
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• 2005

Bile salt deconjugation is the most biologically significant reaction among the bacterial alterations of bile acids in the gastrointestinal tract of human and animal. The responsible enzyme, bile salt hydrolase (BSH), catalyzes the hydrolysis of glycineand/or taurine-conjugated bile salts into amino acid residues and deconjugated bile acids. Herein we review current knowledge on the distribution of BSH activity among various microorganisms with respect to their biochemical and molecular characteristics. The proposed physiological impact of BSH activity on the host animal as well as on the BSH-producing bacterial cells is discussed. BSH activity of the probiotic strains is examined on the basis of BSH hypothesis, which was proposed to explain cholesterol-lowering effects of probiotics. Finally, the potential applications of BSH research are briefly discussed.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.278-285
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• 1999

In order to use heat shock promoter for the detection of toxic substances, dnaK promoter was amplified from E. coli genomic DNA by using a polymerase chain reaction(PCR) followed by sequencing and sub-cloning into the multi-cloning site of the plasmid, pUCD615. The pUCD615 is a broad-host-range vector containing promoterless lux operon originated from V.fischeri. The recombinant plasmid was transfered to E. coli DH5$\alpha$ through electroporation. The recombinant E. coli showed several patterns of bioluminescent responses to ethanol stress. The bioluminescent E. coli also showed responses to other toxic substances including FeK3(CN)6, CdCl2, p-nitrophenol and HgCl2. The increases of RLU(Relative Light Unit) were observed at 100ppm of FeK3(CN)6, 10ppm and 100ppm and 100ppm of CdCl2, 1ppm of 10ppm of p-nitrophenol and at 1ppm of HgCl2.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.578-580
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• 2008

Blue-emitting $CaAl_2Si_2O_8:Eu^{2+}(CAS:Eu^{2+})$ phosphor, prepared by solid-state reaction, is described in this paper. We researched the effect of boron ion substitution in the host materials. The phase and luminescent properties were investigated using the powder X-ray diffraction(XRD) and photoluminescence(PL) spectra.