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Heterologous Expression of a Putative $K^+/H^+$ Antiporter of S. coelicolor A3(2) Enhances $K^+$, Acidic-pH Shock Tolerances, and Geldanamycin Secretion

  • Song, Jae Yang;Seo, Young Bin;Hong, Soon-Kwang;Chang, Yong Keun
    • Journal of Microbiology and Biotechnology
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    • v.23 no.2
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    • pp.149-155
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    • 2013
  • Heterologous expression of a putative $K^+/H^+$ antiporter of Streptomyces coelicolor A3(2) (designated as sha4) in E. coli and Streptomyces hygroscopicus JCM4427 showed enhanced tolerance to $K^+$ stress, acidic-pH shock, and/or geldanamycin production under $K^+$ stress. In a series of $K^+$ extrusion experiments with sha4-carrying E. coli deficient in the $K^+/H^+$ antiporter, a restoration of impaired $K^+$ extrusion activity was observed. Based on this, it was concluded that sha4 was a true $K^+/H^+$ antiporter. In different sets of experiments, the sha4-carrying E. coli showed significantly improved tolerances to $K^+$ stresses and acidic-pH shock, whereas sha4-carrying S. hygroscopicus showed an improvement in $K^+$ stress tolerance only. The sha4-carrying S. hygroscopicus showed much higher geldanamycin productivity than the control under $K^+$ stress condition. In another set of experiments with a production medium, the secretion of geldanamycin was also significantly enhanced by the expression of sha4.

Synthesis and Antimicrobial Activity of 7-[3-Hydroxy-(4-methylthio or 4-methylthiomethyl)pyrrolidinyl]quinoline-3-carboxylic Acids (7-[3-히드록시-(4-메틸티오 또는 4-메틸티오메틸)피롤리디닐]퀴놀린-3-카르복실산의 합성과 항균작용)

  • Lee, Jae-Wook;Son, Ho-Jung;Lee, Kyu-Sam;Yu, Young-Hyo;Yoon, Geal-Jung
    • YAKHAK HOEJI
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    • v.38 no.6
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    • pp.677-682
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    • 1994
  • A number of 7-[3-hydroxy-(4-methylthio or 3-methylthiomethyl)pyrrolidinyl]quinoline-3-carboxylic acids were synthesized by condensation of 7-fluoro substituted quinoline-3-carboxylic acid with 3-hydroxy-4-methylthiopyrrolidine or 3-hydroxy-4-methylthiomethylpyrrolidine. The in vitro antimicrobial activity of them were tested against twenty species of Gram-positive or Gram-negative microorganisms. It showed remarkable antibacterial activity, particularly against Gram-positive microorganisms. Among those 1-cyclopropyl-5-amino-6,8-difluoro 7-(3-hydroxy-4-methylthiomethylpyrrolidinyl)-1,4-dihyd ro-4-oxo-3-quinolinecarboxylic acid(12d) and 1-cyclopropyl-6-fluoro-8-methoxy-7-(3-hydroxy-4-methylthiometby1pyrrolinyl)-1,4-dihydro-4-oxo-3-quinolinocarboxylic acid(12g) showed the most potent in vitro antibacterial activity, and 12d showed better antibacterial activity against MRSA compared to ciprofloxacin and sparfloxacin.

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Magnetic Susceptibilities of the Single Crystal Nd3Se4 (단결정 Nd3Se4의 자기감수율)

  • Cha, Jung-Won;Nahm, Kyun;Kim, Chul-Koo
    • Journal of the Korean Magnetics Society
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    • v.17 no.3
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    • pp.114-119
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    • 2007
  • The single crystal $Nd_3Se_4$ with the $bcc-Th_3P_4$ type structure is grown and the temperature dependent magnetic susceptibilities are measured between 4 K and 300 K. The experimental data are compared with the theoretically calculated susceptibilities which depend on the splitting energies of the $Nd^{3+}$ ground state under the crystal field effect. We find that the magnetic susceptibility of the $Nd^{3+}$ ion in $Nd_3Se_4$ is not affected by the crystal field effect. The spontaneous magnetization curve below $T_c\;=\;53\;K$ of $Nd_3Se_4$ corresponds to the Brillouin function of $Nd_3Se_4$ with J=9/2.

Synthesis of 3-Substituted 4,5-Hexamethylenepyrazole Derivatives as Potential Antihypercholesterolemic Agents (고콜레스테롤혈증 치료제로서 3-치환 4,5-헥사메틸렌피라졸 유도체의 합성)

  • Choe, Young-Hee;Kim, Jin-Il;Jahng, Yurng-Dong
    • YAKHAK HOEJI
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    • v.38 no.4
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    • pp.363-365
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    • 1994
  • A series of 6-[2-(3-substituted 4,5-hexamethylenepyrazo-1-yl)ethyl]tetrahydro-4-hydroxy-2H-pyran-2-ones were synthesized from 3-substituted 4,5-hexamethylenepyrazole in 7 steps as potential antihypercholesterolemic agents.

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Chemical constituents from the stem of Caesalpinia japonica (실거리나무의 성분)

  • Sohn, Soon-Joo;Kwon, Yong-Soo;Kim, Chang-Min
    • Korean Journal of Pharmacognosy
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    • v.31 no.4
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    • pp.430-433
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    • 2000
  • Five compounds have been isolated from the stem of Caesalpinia japonica. On the basis of spectral evidences, the structures of these compounds were identified as 4',7-dihydroxyflavone, 3,4',7-trihydroxyflavone, cathechin, 3',4',7-trihydroxyflavone and 2',3,4',5,6,7-hexahydroxyflavone.

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Performance of Homologous and Heterologous Prime-Boost Immunization Regimens of Recombinant Adenovirus and Modified Vaccinia Virus Ankara Expressing an Ag85B-TB10.4 Fusion Protein against Mycobacterium tuberculosis

  • Kou, Yiming;Wan, Mingming;Shi, Wei;Liu, Jie;Zhao, Zhilei;Xu, Yongqing;Wei, Wei;Sun, Bo;Gao, Feng;Cai, Linjun;Jiang, Chunlai
    • Journal of Microbiology and Biotechnology
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    • v.28 no.6
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    • pp.1022-1029
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    • 2018
  • Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, $IFN-{\gamma}$-producing splenocytes, $CD69^+CD8^+$ T cells, and $IFN-{\gamma}$ secretion when compared with bacillus Calmette-$Gu{\acute{e}}rin$ (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more $IFN-{\gamma}$-producing splenocytes and $CD69^+CD8^+$ T cells, and higher levels of $IFN-{\gamma}$ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of $IFN-{\gamma}$-producing splenocytes sensitive to $CD8^+$ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines ($IFN-{\gamma}$ and $TNF-{\alpha}$) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

Associations of the Porcine Melanocortin-4 Receptor (MC4R) Gene with Growth Traits in Duroc Pigs (듀록 품종의 Melanocortin-4 Receptor(MC4R) 유전자와 성장형질과의 연관성 분석)

  • Cho, K.H.;Kim, M.J.;Choi, B.H.;Jeon, G.J.;Ryu, J.W.;Jung, H.J.;Kim, I.C.;Lee, H.K.;Jeon, G.J.
    • Journal of Animal Science and Technology
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    • v.49 no.4
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    • pp.437-442
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    • 2007
  • The melanocortin-4 receptor(MC4R) is virtually expressed in all brain regions and plays an important role in energy homeostasis in mammals. MC4R has been intensively studied as a trait gene controlling economically important traits, such as growth and feed conversion, etc. Six hundreds and sixty Duroc pigs were genotyped for the MC4R locus and analyzed their relationships with breeding values for average daily gain(ADG), backfat thickness(BF), days to 90kg(D90) and feed conversion(FC). The estimated genotype frequencies for the all Duroc pigs were: 30.8%, 45.2%, 24.1% for AA, AB and BB genotypes, respectively. The mutant A allele was significantly associated with ADG, D90 and BF whereas no significant relationship was found with FC. The change of gene frequencies by generation was shown in both selected and culled groups. These results indicate that the MC4R polymorphism could be integrated in the present selection program to realize a marker-assisted selection for the growth traits of the Duroc population.

An Actual Analysis of Web Accessibility of Disaster Response Agencies using K-WAH4.4 (K-WAH4.4를 이용한 재난대응기관의 웹 접근성 실태분석)

  • Lee, Young-Sik;Choi, Chul-Jae;Jang, Jae-Yeol;Choi, Jin-Sik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.1
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    • pp.149-156
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    • 2015
  • In this paper, the web accessibility of institutions and organizations that are related to disaster response we evaluate analysis. Along with the legal enforcement of Web accessibility, It is because shall comply with web accessibility. we have applied the K-WAH4.4 as an evaluation tool for web accessibility compliance of actual conditions. Look at the degree of compliance with the six detailed procedure of the web site, we request to the improvement of Web accessibility. Based on the guidelines 2.0, looked to the insufficient compliance rate at 61.8%. Then, we propose the need for improvement to enhance Web accessibility.

Experimental and Theoretical Studies on the Tautomerism in 2-Aminopyridines and 2(1H)-Pyridinones: Synthesis of 2-Amino-4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)pyridines and 4-Aryl-3-cyano-6-(3,4-dimethoxyphenyl)-2(1H)-pyridinones

  • Davoodnia, Abolghasem;Attar, Paria;Morsali, Ali;Eshghi, Hossein;Tavakoli-Hoseini, Niloofar;Khadem, Shahriar
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1873-1878
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    • 2011
  • Under solvent-free conditions and in one-pot, a series of 2-amino-4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)-pyridines and 4-aryl-3-cyano-6-(3,4-dimethoxyphenyl)-2(1H)-pyridinones were prepared using 3,4-dimethoxyacetophenone, an aldehyde, malononitrile (or ethyl cyanoacetate), and ammonium acetate in the presence of 3-methyl-1-(4-sulfonylbutyl)imidazolium hydrogen sulfate $[HO_3S(CH_2)_4MIM][HSO_4]$ (a Br${\o}$nsted acidic ionic liquid) as the catalyst in very short reaction time. The preference for the formation of more stable tautomers was consistence with the theoretical calculation using the Gaussian 03 program at the B3LYP hybrid density functional level.

Structural Properties of Dielectric Barrier Reactor with Hole (DBH) for CF4 Decomposition

  • Jung Jung Gun;Kim Jong Suk;Park Jae Yoon;Kim Kwang Soo;Rim Geun Hie
    • Transactions on Electrical and Electronic Materials
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    • v.4 no.4
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    • pp.30-35
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    • 2003
  • In this paper, the $CF_4$ decomposition efficiency is investigated for three simulated plasma reactors that are needle plate reactor, metal particle reactor, and dielectric barrier reactor with hole (DBH). The$CF_4$ decomposition efficiency by DBH is much better than that by needle plate reactor or metal particle reactor. When applied voltage is increased up to the critical voltage for spark formation in the all reactors, the $CF_4$ decomposition efficiency is increased. The $CF_4$ decomposition efficiency in needle plate reactor and metal particle reactor is about $12\%$ and $22\%$ respectively at applied voltage of 23 kV (consumption power: 110 W) and $CF_4$ concentration of 500 ppm, however, the $CF_4$ decomposition efficiency is more than $95\%$ in case of DBH. DBH should be much better than two reactors investigated for $CF_4$ decomposition.