• Title/Summary/Keyword: Absence Culture

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Formate Decarboxylation: Initial Step for Hydrogen Production by Enterobacter aerogenes (Enterobacter aerogenes에 의한 수소 생산 초기 단계인 포메이트 탈카복시 반응 연구)

  • Choi, Jinyoung;Jho, Young Choong;Ahn, Ik-Sung
    • Applied Chemistry for Engineering
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    • v.20 no.4
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    • pp.449-452
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    • 2009
  • The absence of Fe, Se, and Mo in a minimal medium prevented the production of hydrogen from the anaerobic culture of Escherichia coli MC4100. Fe, Se, and Mo are known to be cofactors of formate dehydrogenase ($FDH_{II}$) of both E. coli and Enterobacter aerogenes. Hence when these trace elements are absent in the minimal medium, hydrogen production through formate dehydrogenation would be inhibited not only in E. coli but also in E. aerogenes. Hydrogen production by E. aerogenes 413 was delayed when lacking these trace elements. Therefore, it is believed that hydrogen production of E. aerogenes is initiated not by the reoxidation of nicotinamide adenine dinucleotide (NADH) but by formate decarboxylation.

Regulation of the expression of nhaA gene coding $Na^{+}$/$H^{+}$ antiporter A of escherichia coli

  • Seo, Sung-Yum;Lee, Seung-Heon
    • Journal of Microbiology
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    • v.33 no.2
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    • pp.120-125
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    • 1995
  • .betha.-galactosidase activity of Escherichia coli cells containing operon fusion nhaA'-'lacZ was monitored to study the regulation of expression of nhaA gene under various conditions. The expression of the fusion was enhanced only by chemicals containing Na$^{+}$ or Li$^{+}$. This Na$^{+}$ or Li$^{+}$. This Na$^{+}$(Li$^{+}$)-specific enhancement of .betha.-galactosidase activity represented the increase in the rate of synthesis of .betha.-galactosidase rather than the decrease in the breakdown rate. The induction pattern was influenced by copy numbers of the gene. Induction by Na$^{+}$ or Li$^{+}$ was concentration and time dependent, reaching maximum 5-6 fold induction after 2 hours at 0.4-0.5 M for Na$^{+}$ or at 0.25-0.35 M for Li$^{+}$, Although the expression was induced at much lower concentration of Na$^{+}$ at alkaline pH values than at neutral pH in the presence of Na$^{+}$, alkaline pH itself did ot induced the expression of the fusion in the absence of Na$^{+}$. Temperature shift and growth phase of culture did not affect the level of induction.he level of induction.

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A Study on Grotesque Form in Make-Up (메이크업에 나타난 그로테스크의 조형성)

  • Lee, Sun-Hwa
    • Journal of the Korean Society of Costume
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    • v.61 no.5
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    • pp.34-47
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    • 2011
  • Grotesque make-up causes a visual shock among modern people beyond the standardized beauty definition, attracts their attention, and manifests itself as a phenomenon of "something bizarre, extremely unnatural, ugly, and funny." The purposes of this study were to investigate the characteristics of grotesque in today's make-up as well as its concepts and features and to figure out its aesthetic characteristics based on the results. The research scope was limited to the fashion make-up of the collections from 2005 to 2010 and the advertising make-up during the same period. In the make-up phenomenon examined according to the grotesque characteristics, the pale skin expression, frightened eyes, and emphasis on black induce disgusting fear, sadness, death, sin, fear for life and death, and obsession. As the make-up emphasized only one part by neglecting the original form and exaggerated it to the point of distortion, the exaggerated abnormality led to a sense of social crisis, desperation, and absence of form. As for devilish playfulness, the make-up accompanied by grotesqueness and humor brought the suppressed, closed world in a tight framework out to fluidity and openness, conveying satire, ludicrousness, ridicule, and accusation of the modern society. The heterogeneous disharmony was found in the use of objects in heterogeneous combinations, presenting unreality, fiction, displeasure, ambivalence, and loss of value of human existence.

Preparation of Diphtheria Toxin A Chain from Escherichia coli

  • Lee, Jong-Soo;Yoon, Kyoung-Bum;Park, Jong-Won;Choi, Suk-Jung
    • BMB Reports
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    • v.30 no.2
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    • pp.144-149
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    • 1997
  • An expression vector was constructed containing the gene encoding diphtheria toxin A (DTA) which was placed after a T7 promoter. Cytoplasmic expression of the DTA gene resulted in the formation of an insoluble inclusion body. The inclusion body was collected after the complete lysis of the cell, and subsequent washing with 0.1% Triton X-100 released 16~30% of DTA protein from the inclusion body along with other contaminating proteins. The released DTA protein was purified by dialysis. The remaining pellet was dissolved in 8 M urea containing 5% ${\beta}-mercaptoethanol$, and the denatured DTA was renatured by the dilution-dialysis method. The total yield was 35%, and about 5 mg DTA was obtained from 1 L culture. The DTA protein has a free sulfhydryl group exposed to the protein surface, and was shown to have a tendency to dimerize through disulfide formation in the absence of ${\beta}-mercaptoethanol$. The utility of the sulfhydryl group was tested for the construction of recombinant toxins.

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Genotoxicity study of Aralia elata extract in bacterial and mammalian cell system (두릅나무 추출물의 유전독성평가)

  • 정영신;이석종;최선아;이장하;류재천;홍은경
    • Environmental Mutagens and Carcinogens
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    • v.22 no.4
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    • pp.319-323
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    • 2002
  • In order to investigate the safety of Aralia elata extract causing the reduction in the blood glucose level and oxidative stress in diabetes animals, these genotoxicity studies in bacterial and mammalian cell assay system such as Ames bacterial reverse mutation test and chromosomal aberration assay were performed. As results, in Ames bacterial reversion assay the extract in the range of 5,000-625 ug/plate did not induce mutagenicity in Salmonella typhimurium TA 98, TA 100, TA 1535 and TA 1537 strains with and without metabolic activation of S-9 mixture. For chromosomal aberration assay, $IC_{50}$ (50% inhibition concentration of cell growth) of the extract were determined; 792 $\mu\textrm{g}$/$m\ell$ without and 524 $\mu\textrm{g}$/$m\ell$ with S-9 mixture in Chinese hamster lung (CHL) fibroblast cell culture. Any significant chromosomal aberration was not observed in CHL cells treated with the extract at the concentrations of 792, 396 and 198 $\mu\textrm{g}$/$m\ell$ or 524, 262 and 131 $\mu\textrm{g}$/$m\ell$ in the absence or presence of S-9 metabolic activation, respectively. From these results, Aralia elata extract did not induce any harmful effects on the gene in bacteria and mammalian cell system used in these experiments.

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A Study on the Multiple Disaster Administration's Problem and Improvement (대형 재해관리의 문제점과 개선방안)

  • Kim, Hak-Soo;Koh, Jae-Moon
    • The Korean Journal of Emergency Medical Services
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    • v.7 no.1
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    • pp.179-198
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    • 2003
  • If see disaster administration system of our country, start in terms of is coping by countermeasure after four immediately after disaster occurrence many problems blessing with a sons by tribe and so on of link nature between formation, disaster administration complete charge utensil's absence, disaster charge manpower and budget be indicated and join. If examine improvement way accordingly, is as following ; Necessity of synthetic disaster administration system, Fire fighting formation's independence guarantee, Integration of fire fighting connection similarity business, Disaster administration's permanent establishment complete charge utensil's necessity, Disaster administration midautumn complete charge utensil at a metropolitan autonomous fire fighting system reorganization, Role division of labor between center and local government, Disaster administration professional human strength positivity, Disaster administration information system construction practical use, Equipment and improvement of budget state, Education public information for safety culture consciousness fixing, Internationalization of fire fighting business, globalization propulsion, Structure, member of rescue confrontation system and efficiency. Fire fighting environment is changing greatly, and fire fighting must become center to correspond to do confrontation that do one thing troble when produce disaster.

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Effect of Recombinant Human FSH on the Estrogen Synthesis by Human Fetal Ovarian Tissues Cultured In Vitro (재조합 인간 나포자극 호르몬이 체외배양중인 태아 난소조직의 에스트로젠 합성에 미치는 영향)

  • 이경아
    • Development and Reproduction
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    • v.1 no.1
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    • pp.25-28
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    • 1997
  • The present study was conducted to determine the effect of recombinant human follicle stimulating hormone (rhFSH) on the estrogen synthesis by human fetal ovarian tissues. Fetal ovaries were 18-19 weeks old (18 wks:n=1, 19 wks:n=2). One case of 19-week-old fetal ovaries were obtained from anencephalic fetus. Obtained ovarieswere cleaned and diced around $600\mu\textrm{m}$ pieces, and cultured in the sandwich agar bed system for 21-23 days. Estrone ($E_{1}$) and estradiol-17 $\beta$($E_{2}$) in the medium was measured by radioimmunoassay. Amount of $E_{2}$ synthesis was greater than $E_{1}$ in both normal cases. In contrast, fetal ovaries from anencephalic fetus did not produce neither $E_{1}$ nor $E_{2}$ in the presence or absence of rhFSH. Results suggest that the fetal ovaries have a capacity of estrogen production at 18-19 weeks of gestation Existence of FSH receptor is also supposed. Different results by anecephalic fetal ovaries suggest the difference in the development between normal and anencephalic fetal ovaries.

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Characterization of the Mutant of Streptomyces sp. SL-387(KCTC 0102BP) Producing Aminopeptidase M Inhibitors (Aminopeptidase M 저해제를 생산하는 Streptomyces sp. SL-387 (KCTC 0102BP) 변이주의 특성)

  • Chung, Myung-Chul;Chun, Hyo-Kon;Lee, Ho-Jae;Lee, Choong-Hwan;Kho, Yung-Hee
    • Microbiology and Biotechnology Letters
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    • v.23 no.1
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    • pp.47-52
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    • 1995
  • Since the original productivity of new aminopeptidase M inhibitors MR-387A and B by Streptomyces sp. SL-387 (KCTC 0102BP) was not enough for further chemical and biological evaluation, mutation of parent strain by the treatment of N-methyl-N'-nitro-N-nitrosoguanidine was performed in order to obtain a clone with greater inhibitory activity. Mutant N-3 was selected due to a 6-fold greater productivity (40 $\mu$g/ml) than that of the wild type(6.7 $\mu$g/ml). This mutant was resistant to 3,4-dehydro-DL-proline, an antimetabolite of proline, with 25 $\mu$g/ml of minimum inhibitory concentration. Furthermore, the characteristic morphological change from spiral spore chain in wild type to straight in mutant was observed. An aminopeptidase M nhibitor different from MR-387A and B was isolated from the culture broth of the mutant. This inhibitor was composed of 2 proline, 1 valine, and an unknown amino acid which is presumably 3-amino-4-phenylbutanoic acid. IC$_{50}$ value (89.1 $\MU$g/ml) of the purified inhibitor was lower than that of other inhibitors, which may be due to the absence of 2(S)-hydroxyl group within the structure of 3-amino-4-phenyl- butanoic acid.

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Evidence That Temporally Alternative Expression of the Vibrio vulnificus Elastase Prevents Proteolytic Inactivation of Hemolysin

  • Rhee, Jee-Eun;Lee, Jeong-Hyun;Jeong, Hye-Sook;Park, U-Ryung;Lee, Dong-Ha;Woo, Gun-Jo;Miyoshi, Shin-Ichi;Choi, Sang-Ho
    • Journal of Microbiology and Biotechnology
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    • v.13 no.6
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    • pp.1021-1026
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    • 2003
  • Numerous secreted and cell-associated virulence factors have been proposed to account for the fulminating and destructive nature of Vibrio vulnificus infections. Among the putative virulence factors are an elastase, elastolytic protease, and a cytolytic hemolysin. Effects of the elastase on the hemolysin were assessed by evaluating changes of hemolytic activities either in the presence or absence of the protease. Although hemolytic activity in the culture supernatant was lowered by the purified elastase added in vitro, the cellular level of hemolytic activity was unaffected by the mutation of vvpE encoding the elastase. Growth kinetic studies revealed that hemolysin reached its maximum level in the exponential phase of growth, and the elastase appeared at the onset of the stationary phase. These results have provided insight into the regulation of virulence factors: temporally coordinate regulation of virulence factors is essential for the overall success of the pathogen during pathogenesis.

Isolation of a Pseudomonas sp. Capable of Utilizing 4-Nonylphenol in the Presence of Phenol

  • Chakraborty Joydeep;Dutta Tapan K.
    • Journal of Microbiology and Biotechnology
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    • v.16 no.11
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    • pp.1740-1746
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    • 2006
  • Enrichment techniques led to the isolation of a Pseudomonas sp. strain P2 from municipal waste-contaminated soil sample, which could utilize different isomers of a commercial mixture of 4-nonylphenol when grown in the presence of phenol. The isolate was identified as Pseudomonas sp., based on the morphological, nutritional, and biochemical characteristics and 16S rDNA sequence analysis. The ${\beta}$-ketoadipate pathway was found to be involved in the degradation of phenol by Pseudomonas sp. strain P2. Gas chromatography-mass spectrometric analysis of the culture media indicated degradation of various major isomers of 4-nonylphenol in the range of 29-50%. However, the selected ion monitoring mode of analysis of biodegraded products of 4-nonylphenol indicated the absence of any aromatic compounds other than those of the isomers of 4-nonylphenol. Moreover, Pseudomonas sp. strain P2 was incapable of utilizing various alkanes individually as sole carbon source, whereas the degradation of 4-nonylphenol was observed only when the test organism was induced with phenol, suggesting that the degradation of 4-nonylphenol was possibly initiated from the phenolic moiety of the molecule, but not from the alkyl side-chain.