• Molecules and Cells
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• 제25권4호
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• pp.553-558
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• 2008

Essential aspects of the innate immune response to microbial infection appear to be conserved between insects and mammals. In order to identify new Drosophila melanogaster genes involved in the immune response, we performed gene expression profiling of Drosophila SL2 cells stimulated with bacterial (LPS/PGN) or fungal (curdlan) components using a cDNA microarray that contained 5,405 Drosophila cDNAs. We found that some genes were similarly regulated by LPS/PGN and curdlan. However, a large number, belonging to the functional classes of cell organization, development, signal transduction, morphogenesis, cell cycle, and DNA replication, displayed significant differences in their transcription profiles between the two treatments, demonstrating that bacterial and fungal components induce different immune response even in an in vitro cell system.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.151-152
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• 2002

Bacterial infection is a very complex process in which both pathogenic microorganisms and host cells play crucial roles, and it is the outcome of interactions between the two participants. To elucidate the bacterial pathogenesis mechanisms, therefore, it is essential to understand the cellular and systemic responses of the host as well as the virulence factors of the pathogen. Infection of a host by pathogenic bacteria causes drastic changes in the physiology of host cells, leading to activation of a program of various gene expression. (omitted)

• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.259-270
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• 2020

Listeria monocytogenes is a gram-positive, facultative anaerobe food pathogen responsible for the listeriosis that mostly occurs during the low-temperature storage of a cold cut or dairy products. To understand the systemic response to a wide range of growth temperatures, L. monocytogenes were cultivated at a different temperature from 10℃ to 42℃, then whole cell proteomic analysis has been performed both exponential and stationary cells. The specific growth rate increased proportionally with the increase in growth temperature. The maximum growth rate was observed at 37℃ and was maintained at 42℃. Global protein expression profiles mainly depended on the growth temperatures showing similar clusters between exponential and stationary phases. Expressed proteins were categorized by their belonging metabolic systems and then, evaluated the change of expression level in regard to the growth temperature and stages. DnaK, GroEL, GroES, GrpE, and CspB, which were the heat&cold shock response proteins, increased their expression with increasing the growth temperatures. In particular, GroES and CspB were expressed more than 100-fold than at low temperatures during the exponential phase. Meanwhile, CspL, another cold shock protein, overexpressed at a low temperature then exponentially decreased its expression to 65-folds. Chemotaxis protein CheV and flagella proteins were highly expressed at low temperatures and stationary phases. Housekeeping proteins maintained their expression levels constant regardless of growth temperature or growth phases. Most of the growth related proteins, which include central carbon catabolic enzymes, were highly expressed at 30℃ then decreased sharply at high growth temperatures.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.576-576
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• 2003

• BMB Reports
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• 제40권5호
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• pp.656-661
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• 2007

In this report, we describe an optimized method for generation of ephA8 BAC transgenic mice expressing the lacZ reporter gene under ephA8 regulatory sequences. First, we constructed a targeting vector that carries a 1.2 kb ephA8 DNA upstream of its first exon, a lacZ expression cassette, a kanamycin cassette, and a 0.7 kb ephA8 DNA downstream of its first exon. Second, the targeting vector was electroporated into cells containing the ephA8 BAC and pKOBEGA, in which recombinases induce a homologous recombination between the ephA8 BAC DNA and the targeting vector. Third, the FLP plasmid expressing the Flipase was electroporated into these bacteria to eliminate a kanamycin cassette from the recombinant BAC DNA. The appropriate structures of the modified ephA8 BAC DNA were confirmed by Southern analysis. Finally, BAC transgenic mouse embryos were generated by pronuclear injection of the recombinant BAC DNA. Whole mount X-gal staining revealed that the lacZ reporter expression is restricted to the anterior region of the developing midbrain in each transgenic embryo. These results indicate that the ephA8 BAC DNA contains most, if not all, regulatory sequences to direct temporal and spatial expression of the lacZ gene in vivo.

• Journal of Microbiology and Biotechnology
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• 제20권7호
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• pp.1156-1162
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• 2010

During ethanol fermentation, bacterial strains may encounter various stresses, such as ethanol and acid shock, which adversely affect cell viability and the production of ethanol. Therefore, ethanologenic strains that tolerate abiotic stresses are highly desirable. Bacteria of the genus Deinococcus are extremely resistant to ionizing radiation, ultraviolet light, and desiccation, and therefore constitute an important pool of extreme resistance genes. The irrE gene encodes a general switch responsible for the extreme radioresistance of D. radiodurans. Here, we present evidence that IrrE, acting as a global regulator, confers high stress tolerance to a Zymomonas mobilis strain. Expression of the gene protected Z. mobilis cells against ethanol, acid, osmotic, and thermal shocks. It also markedly improved cell viability, the expression levels and enzyme activities of pyruvate decarboxylase and alcohol dehydrogenase, and the production of ethanol under both ethanol and acid stresses. These data suggest that irrE is a potentially promising gene for improving the abiotic stress tolerance of ethanologenic bacterial strains.

• International Journal of Oral Biology
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• 제41권4호
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• pp.237-242
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• 2016

Interleukin-1b ($IL-1{\beta}$), a proinflammatory cytokine, regulates the innate immune responses against bacterial infection. Mature $IL-1{\beta}$ is produced from $pro-IL-1{\beta}$ by activated caspase-1, which in turn is activated by the inflammasome complex formation. In this study, we compared the inflammasome mRNA expression induced by S. sanguinis, S. oralis, F. nucleatum and P. intermedia. Among the tested bacteria, S. sanguinis induced the highest $IL-1{\beta}$ secretion. S. oralis, F. nucleatum and P. intermedia induced very weak $IL-1{\beta}$ secretion. S. sanguinis mostly induced the NLRP3 mRNA expressions. Although F. nucleatum did not induce high $IL-1{\beta}$ secretion, it induced high expression levels of AIM2, NLRP2, and NLRP3. No specific inflammasomes were induced by S. oralis and P.intermedia. Studying the inflammasome complex activation induced by oral bacteria may thus enhance our understanding of the pathogenesis of oral diseases.

• 대한의생명과학회지
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• 제12권3호
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• pp.139-143
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• 2006

Jopock (Jpk) has previously been ascertained that induces both bacterial and mammalian cell death. The Escherichia coli cells expressing Glutathion S-transferase (GST) fused Jpk showed elongated phenotype and inhibited cell growth which led eventual cell death. In an attempt to search the genetic suppressor of the lethal protein Jpk in bacterial cells, we constructed a unidirectional protein expression vector inserting tac promoter next to the C-terminus Jpk in pGEX-Jpk. The function of additional tac promoter was confirmed by substituting lac promoter in Plac-TOPO plasmid. The cells harboring plac- TOPO, which regulates $lacZ{\alpha}$ gene expression under lac promoter, formed blue colonies in 5-bromo-4-3 $indolyo-{\beta}-D-galactoside$ (X-gal) plate. When lac promoter was changed to tac promoter, same results were observed. Since the addition of tac promoter did not affect the toxic effect of Jpk, the pGEX-Jpk-ptac could be a useful vector for the screening of suppressor(s) for Jpk, in which GST-Jpk and a putative Jpk-suppressing protein are coexpressing from two unidirectional tac promoters, which response to the same inducer, $isopropyl-{\beta}-D-thiogalactopyranoside (IPTG)$.

• Journal of Plant Biotechnology
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• 제40권1호
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• pp.49-54
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• 2013

C3HC4-type RING zinc finger proteins essential in the regulation of plant processes, including responses to abiotic stresses. We previously isolated and examined the C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under abiotic stresses. To elucidate the role of the BrRZFP1 transcription factor in gene regulation, we transformed tobacco plants with the BrRZFP1 gene. Plants were regenerated from 82 independently transformed callus lines of tobacco and analysed for transgene expression. Transgene integration and expression was confirmed by Southern and RT-PCR analyses, respectively. T2 plants displayed more tolerance to the bacterial pathogens Pectobacterium carotovorum and Ralstonia solanacearum, and the tolerance levels were correlated with BrRZFP1 expression levels. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and its overexpression in plants could increase biotic stress resistance.

• BMB Reports
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• 제39권6호
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• pp.703-708
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• 2006

During infection, the common respiratory tract pathogen Streptococcus pneumoniae encounters several environmental conditions, such as upper respiratory tract, lung tissue, and blood stream, etc. In this study, we examined the effects of blood on S. pneumoniae protein expression using a combination of highly sensitive 2-dimensional electrophoresis (DE) and MALDI-TOF MS and/or LC/ESI-MS/MS. A comparison of expression profiles between the growth in THY medium and THY supplemented with blood allowed us to identify 7 spots, which increased or decreased two times or more compared with the control group: tyrosyl-tRNA synthetase, lactate oxidase, glutamyl-aminopeptidase, L-lactate dehydrogenase, cysteine synthase, ribose-phosphate pyrophosphokinase, and orotate phosphoribosyltransferase. This global approach can provide a better understanding of S. pneumoniae adaptation to its human host and a clue for its pathogenicity.