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Medium Optimization for Phytase Production by Recombinant Escherichia coli Using Statistical Experimental Design

  • Choi, Won-Chan;Oh, Byng-Chul;Kim, Hyung-Kwoun;Lee, Eun-Sook
    • Journal of Microbiology and Biotechnology
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    • v.12 no.3
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    • pp.490-496
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    • 2002
  • The production of E. coli WC7 phytase from a recombinant E. coli strain was optimized using a statistical experimental design approach. Two-level complete factorial designs with seven variables were used for the media optimization. In the first optimization step, the influence of disodium succinate, yeast extract, $K_2HPO_4,\;NH_4H_2PO_4,\;MgSO_4$, NaCl, and trace elements on phytase production was evaluated. As a result, disodium succinate, yeast extract, $NH_4H_2PO_4$, NaCl, and the trace elements were found to have a positive influence on the phytase production, while $K_2HPO_4\;and\;MgSO_4$ had a negative influence. In the second step, the concentrations of disodium succinate and yeast extract were further optimized using central composite designs. The maximum phytase activity obtained was 234 U/ml using 15.9 g/1 disodium succinate, 20 g/1 yeast extract, 5 g/1 K_2HPO_4,\;10 g/1 NH_4H_2PO_4,\;1.5 g/1 MgSO_4$, 4 g/1 NaCl, and 1.5 m1/1 trace elements, which was about a 14-fold increase in comparison with that obtained using the basal medium.

Nuclear localization of Obox4 is dependent on its homeobox domain

  • Park, Geon Tae;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.40 no.1
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    • pp.1-6
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    • 2013
  • Objective: Oocyte-specific homeobox 4 (Obox4) is preferentially expressed in oocytes and plays an important role in the completion of meiosis of oocytes. However, the Obox4 expression pattern has not been reported yet. In this study, we investigated the subcellular localization of Obox4 using a green fluorescent protein (GFP) fusion expression system. Methods: Three regions of Obox4 were divided and fused to the GFP expression vector. The partly deleted homeodomain (HD) regions of Obox4 were also fused to the GFP expression vector. The recombinant vectors were transfected into HEK-293T cells plated onto coated glass coverslips. The transfected cells were stained with 4',6-diamidino-2-phenylindol and photographed using a fluorescence microscope. Results: Mutants containing the HD region as well as full-length Obox4 were clearly localized to the nucleus. In contrast, the other mutants of either the N-terminal or C-terminal region without HD had impaired nuclear localization. We also found that the N-terminal and C-terminal of the Obox HD contributed to nuclear localization and the entire HD was necessary for nuclear localization of Obox4. Conclusion: Based on the results of the present study, we demonstrated that the intact HD region of Obox4 is responsible for the nuclear localization of Obox4 protein in cells.

Development of Strain-Specific Primers for Identification of Bifidobacterium bifidum BGN4

  • Youn, So Youn;Ji, Geun Eog;Han, Yoo Ri;Park, Myeong Soo
    • Journal of Microbiology and Biotechnology
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    • v.27 no.5
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    • pp.909-915
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    • 2017
  • Bifidobacterium bifidum BGN4 (BGN4) has many proven beneficial effects, including antiallergy and anticancer properties. It has been commercialized and used in several probiotic products, and thus strain-specific identification of this strain is very valuable for further strain-dependent physiological study. For this purpose, we developed novel multiplex polymerase chain reaction (PCR) primer sets for strain-specific detection of BGN4 in commercial products and fecal samples of animal models. The primer set was tested on seven strains of B. bifidum and 75 strains of the other Bifidobacterium species. The BGN4-specific regions were derived using megaBLAST against genome sequences of various B. bifidum databases and four sets of primers were designed. As a result, only BGN4 produced four PCR products simultaneously whereas the other strains did not. The PCR detection limit using BGN4-specific primer sets was $2.8{\times}10^1CFU/ml$ of BGN4. Those primer sets also detected and identified BGN4 in the probiotic products containing BNG4 and fecal samples from a BGN4-fed animal model with high specificity. Our results indicate that the PCR assay from this study is an efficient tool for the simple, rapid, and reliable identification of BGN4, for which probiotic strains are known.

Comparative Analysis on Descriptive Rules of RDA and KCR4 (RDA와 KCR4의 기술규칙 분석에 관한 연구)

  • Park, Jin-Hee
    • Journal of Korean Library and Information Science Society
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    • v.40 no.2
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    • pp.111-138
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    • 2009
  • The Joint Steering Committee represented final draft of RDA that can be replaced for AACR3 on November third in 2008. RDA is aiming at standard of international cataloging rules fo the purpose of providing the bibliographic description and the access point of all media, and when it will be realized, KCR4 4th edtion have to revised to following up it. This study analyzes both cataloging rules of RDA and KCR4 in each area of KCR 4th edition. As a result, it present the points to take into consideration as revising KCR4.

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Syntheses and Biological Activities of Potential Antifungal Allylamine Compounds (항진균 알릴아민 화합물의 합성과 활성평가)

  • Chung Byung-Ho;Cheon Seung-Hoon;Chung Soon-Young
    • YAKHAK HOEJI
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    • v.49 no.4
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    • pp.299-305
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    • 2005
  • Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 3,4-difluorophenyl (2a-5a), 4-hydroxyphenyl (2b-5b), 3-nitro­phenyl (2c-5c), 4-chlorobenzothiazoly (2d-5d) and 5-methylfurfural (2e-5e) instead of naphthyl group, and with hydrogen (3a-3e), methyl (4a-4e) and ethyl (5a-5e) in the place of methyl in naftifine were synthesized and tested for their in vitro anti-fungal activities against five different fungi. Fourteen compounds (3a, 4a, 5a, 3b, 4b, 5b, 3c, 4c, 5c, 3d, 4d, 3e, 4e and 5e) showed significant anti-fungal activities against T. mentagrophytes. (E)-N-(3-Phenyl-2-propenyl)-3,4-difluoro-ben­zenemethaneamine(3a), (E)_N_(3_phenyl_2_propenyl)_4_hydroxy_benzenemethaneamine(3b) and (E)-N-ethyl-N-(3-phenyl­2-propenyl)-3-nitro-benzenemethaneamine (5c) displayed moderate anti-fungal activities against all five different fungi.

Isolation and characterization of 4-chlorophenoxyacetic acid-degrading bacteria from agricultural soils

  • Chung, Min-Jae;Shin, Se-Young;Park, Yong-Keun;Min, Kyung-Hee;Ka, Jong-Ok
    • Journal of Microbiology
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    • v.35 no.2
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    • pp.117-122
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    • 1997
  • Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

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Grignard Metathesis Polymerization and Properties of 1,1-Disubstituted-2,5-dibromo-3,4-diphenylsiloles

  • Park, Young Tae
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1825-1831
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    • 2014
  • Grignard metathesis polymerizations of 1,1-disubstituted-2,5-dibromo-3,4-diphenylsiloles such as 1,1-dimethyl-2,5-dibromo-3,4-diphenylsilole, 1,1-diethyl-2,5-dibromo-3,4-diphenylsilole, 1,1-diisopropyl-2,5-dibromo-3,4-diphenylsilole, and 1,1-dihexyl-2,5-dibromo-3,4-diphenylsilole were performed to yield poly(1,1-disubstituted-3,4-diphenyl-2,5-silole)s containing fluorescent aromatic chromophore groups such as phenyl and silole in the polymer main chain: poly(1,1-dimethyl-3,4-diphenyl-2,5-silole), poly(1,1-diethyl-3,4-diphenyl-2,5-silole), poly(1,1-diisopropyl-3,4-diphenyl-2,5-silole), and poly(1,1-dihexyl-3,4-diphenyl-2,5-silole), respectively. The obtained materials are highly soluble in common organic solvents such as chloroform and tetrahydrofuran. Fourier-transform infrared spectra of all the polymers have characteristic C=C stretching frequencies at $1620-1628cm^{-1}$. The prepared organosilicon polymers exhibit strong absorption maximum peaks at 273-293 nm in the tetrahydrofuran solution, showing a red-shift of 18-34 nm relative to those of the monomer, strong excitation maximum peaks at 276-303 nm, and strong fluorescence emission maximum bands at 350-440 nm. Thermogravimetric analysis shows that most of the polymers are stable up to $200^{\circ}C$ with a weight loss of 6-16% in nitrogen.

A Study On Field Test of IGBT Type Propulsion System fo Electric oilway (전동차용 IGBT형 추진제어장치의 본선시험에 관한 연구)

  • 정만규;고영철;방이석;서광덕
    • The Transactions of the Korean Institute of Power Electronics
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    • v.5 no.5
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    • pp.515-521
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    • 2000
  • This paper describes the field test results of IGBT VVVF inverter for the railway propulsion system. The 1,650kVA IGBT VVVF inverter has been developed. Therefore, the field test is performed in SMG 6 Line to confirm its the reliability and performance. The train consists of 4M4T and the electrical equipment for field test are as follows : VVVF inverter 4 sets, 16 traction motors and 2 SIVs. The propulsion system is composed with 1C4M(1-Controller 4-Motors). The results of propulsion system which have the excellent acceleration/deceleration and the jerk characteristics as well as starting ability on slope are taken through the field test.

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Effect of Luminescence with Coactivator of $ZnGa_2O_4$:Mn,X phosphor ($ZnGa_2O_4$:Mn,X 형광체의 부활성제에 따른 발광 효과)

  • 박용규;한정인;주성후
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.3
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    • pp.242-247
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    • 1998
  • In this study, we have synthesized $ZnGa_2O_4$:Mn,X powder doped with Mn, MnO, $MnF_2$ and $MnCl_2$, low voltage green emitting phosphor, in vacuum atmosphere. From PL spectra, the intensity of the emission peak, the brightness with coactivator show that $ZnGa_2O_4$:Mn,Cl > $ZnGa_2O_4$:Mn,F > $ZnGa_2O_4$:Mn,O > $ZnGa_2O_4$:Mn. These improvement of the brightness are caused by the increase of the concentration of $Mn^{2+}$ ion. In case of $ZnGa_2O_4$:Mn,Cl and ZnGa$_2$O$_4$:Mn,F, the brightness is enhanced much more, which is owed to the decrease of defect of host material. For $ZnGa_2O_4$:Mn,Cl phosphor fabricated with optimized condition, the decay time becomes short from 30 ms of the $ZnGa_2O_4$:Mn and $ZnGa_2O_4$:Mn,O to 6 ms and the brightness of CL at 1 kV, 1 mA is 60 cd/$m^2$.

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4차산업혁명전문대학원 설립방안 연구

  • Bae, Ho-Yeong
    • 한국벤처창업학회:학술대회논문집
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    • 2018.04a
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    • pp.23-25
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    • 2018
  • 본 연구는 우리나라가 글로벌 시장에서 4차 산업혁명 시대를 주도하는데 필요한 4차 산업혁명 전문가 양성에 초점을 두고, 4차산업혁명전문대학원 설립방안을 제시하고자 한다. 이를 위하여 국내 타특수대학원인 창업대학원과 컨설팅대학원을 비교고찰하였고, 해외 타전문대학원인 일본 회계전문대학원과 일본 법학전문대학원을 비교고찰하였다. 그 결과, 4차 산업혁명 전문가 양성을 위하여 4차산업혁명전문대학원 설립방안을 다음과 같이 제시하고자 한다. 첫째, 4차산업혁명전문대학원은 4차 산업혁명 전문가 양성을 위한 차별화되고 융합화된 교과과정으로 2~3년제 전문대학원 석박사과정으로 운영될 필요가 있다. 둘째, 4차산업혁명전문대학원은 전문석(박)사 학위과정이므로 교육의 내실화를 위하여 야간보다는 주간과정으로 운영될 필요가 있으며, 트랙제를 적극 활용하여 경영학, 회계학, 법학, 창업학, 공학 등 학제간 융합적 교과과정으로 설계되어야 한다. 또한 이론교육과 실무교육의 균형적 교과과정으로 실무교육이 전체 교육과정에 30% 이상이 되도록 해야 한다. 셋째, 4차산업혁명전문대학원은 정부(중소벤처기업부)의 전략적인 재정 지원이 필수적이며, 재정 지원과 함께 교육의 질에 대한 평가인증을 지속적으로 받아야 할 것이다. 또한 장기적으로는 중소벤처기업부의 창업대학원 및 컨설팅대학원이 4차산업혁명전문대학원으로 통합될 필요가 있다.

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