• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2007년도 International Meeting of the Microbiological Society of Korea
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• pp.83-85
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• 2007

Deep-sea bacteria are adapted to extreme environments, such as high pressures and cold temperatures. We have isolated many piezophiles which grow well even under high pressures from deep-sea sediment. Shewanella violacea DSS12 and Moritella japonica DSK1 have the ability to grow at up to 70 MPa, and those bacteria have unique mechanisms of gene expression in response to high pressure conditions. The combination of gene expression systems in piezophiles, like the high pressure-dependent promoters and GFP reporter gene, may reveal highly fluorescent cells when exposed to high hydrostatic pressure conditions. It is predicted that a novel bio-sensing system can be made to probe high pressure environments using living bacteria. First, gene transformation into our piezophiles, strains DSS12 and DSK1, were examined. Eschericha coli S17-1 was used for bacterial conjugation with those piezophiles. As a result, the broad host range vector, pKT231, and the shuttle vector, pTH10, were successfully introduced to DSS12 and DSK1, respectively. Next, The pressure regulated promoters from DSS12 and DSK1 were cloned into proper vectors and combined with GFP as a reporter gene downstream of each promoter. The transformants of DSK1 and DSS12 with the recombinant pTH10 and pKT231 plasmid, which has cadA and glnA promoters (each of them is a pressure regulated promoter from DSK1 and DSS12, respectively) and GFP, were grown under high pressure and gene expression of GFP promoted by 50 MPa pressure was confirmed. This is a critical point to create a pressure-sensing bacteria, as the "High Pressure Glow Cells", which will indicate the level of environmental pressure using fluorescence of GFP as a reporter gene.

• Reproductive and Developmental Biology
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• 제30권2호
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• pp.81-85
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• 2006

This study was conducted to examine the effect of IRES controlled reporter gene on screening and production of recombinant human erythropoietin (EPO) proteins from cultured CHO cells. The cDNA was cloned for EPO from human liver cDNA Using site-directed mutagenesis, we generated recombinant human EPO (rhEPO) with two additional N-glycosylations (Novel erythropoiesis-stimulating protein: NESP). Wild type hEPO and NESP were cloned into expression vectors with GFP reporter gene under regulatory control of CMV promoter and IRES so that the vectors could express both rhEPO and GFP. The expression vectors were transfected to cultured CHO-K1 cells. Under microscopy, expression of GFP was visible. Using supernatant of the culture, ELISA assay, immunocytochemistry and in vitro assay using EPO dependant cell line were performed to estimate biological activity to compare the production characteristics (secretion levels, etc.) between rhEPO and NESP. The activity of NESP protein, obtained by mutagenesis, was described and compared with its rhEPO counterpart produced under same conditions. Although NESP had less secretion level in CHO cell line, the biological activity of NESP was greater than that of rhEPO. These results are consistent with previous researches. We also demonstrated that rhEPO and GFP proteins expressed simultaneously from transfected CHO cell line. Therefore we conclude that use of GFP reporter gene under IRES control could be used to screen and produce rhEPO in cultured CHO cells.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권1호
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• pp.6-10
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• 1998

A plasmid vector containing two reporter genes, mer-lux and lac-GFP, was transformed to both Escherichia coli and Pseudomonas putida. Their cellular activities and biofilm characteristics were investigated in flow-cell units by measuring bioluminescent lights and fluorescent levels of GFP. Bioluminescence was effective to monitor temporal cell activities, whereas fluorescent level of GFP was useful to indicate the overall cell activities during biofilm development. The light production rates of E. coli and P. putida cultures were dependent upon concentrations of HgCl2. Mercury molecules entrapped in P. putida biofilms were hardly washed out in comparison with those in E. coli biofilms, indicating that P. putida biofilms may have higher affinity to mercury molecules than E. coli biofilms. It was observed that P. putida expressed GFP cDNA in biofilms but not in liquid cultures. This may indicate that the genetic mechanisms of P. putida were favorably altered in biofilm conditions to make a foreign gene expression possible.

• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1213-1216
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• 2007

The vector pCW5 with plasmid pC7, originally isolated in Lactobacillus paraplantarum C7 derived from kimchi, was constructed using a p32 strong promoter, the pC7 replicon, and green fluorescent protein (GFP) as the reporter. The constructed vector was transformed into E. coli and Leuconostoc mesenteroides, and GFP expression detected using a Western blot analysis. GFP fluorescence was recognized in E. coli and Leuconostoc mesenteroides using a confocal microscope. In addition, GFP fluorescence was also clearly detected in several industrially important lactic acid bacteria (LAB), including Lactobacillus bulgaricus, Lactobacillus paraplantarum, and Lactobacillus plantarum. Thus, pCW5 was shown to be effective for Leuconostoc mesenteroides when using GFP as the reporter, and it can also be used as a broad-host-range vector for other lactic acid bacteria.

• Journal of Plant Biotechnology
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• 제35권2호
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• pp.109-114
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• 2008

Agrobacterium 공동배양을 적용하여 소포자에 Agrobacterium-mediated genetic transformation이 가능한지를 조사하기 위하여 소포자 형질전환에 대한 조건을 구축하고자 하였다. 선발 배지에서 Kanamycin에 대한 소포자의 배발생율을 조사하였는데 Kanamycin 농도 10 mg/L, 50 mg/L, 100 mg/L를 처리하였을 때 배발생율이 각각 4배, 8배, 10배 이하로 감소하였고 Kanamycin이 형질전환 선발마커로 사용할 경우 형질 전환율이 매우 낮아질 것으로 사려 된다. GFP 유전자 발현을 이용하여 visual reporter로서 활용하고자 Agrobacterium과 공동배양 후 배발생 유도 배지에 치상하고 소포자가 배로 발생하는 과정을 현미경으로 조사하면서 GFP 발현을 관찰하였다. 소포자는 배양 12일째서부터 소포자 분열로 cluster를 형성하였으며 24일째에는 반복되는 분열을 통하여 큰 mass의 배로 발달된 모습을 각각 GFP 발현을 통해 볼 수 있었다. 배양48일째도 GFP발현이 계속 보이며 총 8 개의 배에서 GFP 발현 재현성을 보임으로서 형질전환은 된 것으로 보이지만 더 이상 성숙된 배로 자라지 않아 소포자를 이용한 Agrobacterium 형질전환 조건을 더 개선할 필요가 있다.

• 한국어병학회지
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• 제16권2호
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• pp.69-73
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• 2003

In this study, GFP reporter gene was transfected into a fibroblast cell line RTG-2 using a polycationic transfection reagent (Superfect) and showed a successful expression of GFP. The transfection efficiency by Superfect was compared to the commonly used transfection method, i.e. DNA-calcium phosphate coprecipitatlon. Transfection by Superfect was more effective than calcium phosphate coprecipltation method (frequency of cell expressing orr was 11.3% and 3.5%, respectively). The optimal expression of GFP and {\beta}-galactosidase was observed when $5-6\;{\mu}{\ell}$ of Superfect per ${\mu}g$ DNA was used for transfcction, 1:5-6 ratio between DNA(${\mu}g$) and Superfect ($\mu\ell$).

• Asian-Australasian Journal of Animal Sciences
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• 제27권3호
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• pp.324-329
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• 2014

To facilitate the construction of genetically-modified pigs, we produced cloned embryos derived from porcine fibroblasts transfected with a pair of engineered zinc finger nuclease (ZFN) plasmids to create targeted mutations and enriched using a reporter plasmid system. The reporter expresses RFP and eGFP simultaneously when ZFN-mediated site-specific mutations occur. Thus, double positive cells ($RFP^+/eGFP^+$) were selected and used for somatic cell nuclear transfer. Two types of reporter based enrichment systems were used in this study; the cloned embryos derived from cells enriched using a magnetic sorting-based system showed better developmental competence than did those derived from cells enriched by flow cytometry. Mutated sequences, such as insertions, deletions, or substitutions, together with the wild-type sequence, were found in the cloned porcine blastocysts. Therefore, genetic mutations can be achieved in cloned porcine embryos reconstructed with ZFN-treated cells that were enriched by a reporter-based system.

• 생명과학회지
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• 제17권2호통권82호
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• pp.293-297
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• 2007

형광단백질 (green fluorescent protein, GFP)은 생물공정을 살피데 지표 단백질로 유용하게 사용이 된다. 본 연구에서는 쌀세포에서 외래 단백질의 발현양상을 관찰하기 위해서, 표지 단백질로 GFP를 형질전환 후 이것에서 유도된 현탁세포에서 GFP의 발현 양상을 관찰하였다. 형질전환시 GFP의 발현을 위한 프로모터로 RAmysE를 사용하였으며 이것은 배양액 중에서 당이 고갈되었을 때 강력히 작동된다. 그래서 본 연구에서는 배양액 중에 다양한 슈크로오스 농도로 쌀세포를 배양하여 세포의 성장양태 및 GFP의 발현양에 미치는 영향을 관찰한 결과 세포의 성장은 12%의 당농도에서 7.06g/L로 최적이였으며 GFP는 당을 가장 적게 사용한 3%에서 최적임을 알 수가 있었다. 이것은 세포의 성장과 GFP의 생산에 사용된 당이 반대로 영향을 미침을 알 수가 있었으며 향후 최적의 대량배양을 위해서는 세포의 성장과 산물의 생산시기를 분리한 이단계 배양법이 필요함을 암시한다.

• Journal of Microbiology
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• 제42권3호
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• pp.243-247
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• 2004

Sphingomonas chlorophenolica ATCC39723 was successfully labeled with the gfp (green fluorescent protein) gene inserted into the pcpB gene by homologous recombination. As the gfp recombinant was easily distinguished from other indigenous organisms, the population of gfp recombinant was monitored after being released into the soil microcosms. Their population density dropped from 10$\^$8/ to 10$\^$6/ (cfu/$m\ell$) in the non-sterilized soil microcosms during the first 6 days. Moreover, the gfp recombinant was not detected even at lower dilution rates after a certain time period. The recombinant, however, survived for at least 28 days in the sterilized soil microcosms. Although the gfp recombinant did not degrade pentachlorophenol (PCP), this experiment showed the possibility of using gfp as a monitoring reporter system for S. chlorophenolica ATCC39723 and potentially other species of Sphingomonas.

• Animal cells and systems
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• 제6권4호
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• pp.317-322
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• 2002

To improve conventional yeast one-hybrid screening, we have developed an efficient mammalian one-hybrid system that allows rapid isolation of com-plementary DNAs which are able to induce human p14$^{ARF}$. tumor suppressor gene. A 1.5 kb promoter region of p14$^{ARF}$ was fused to EGFP to generate ARF promoter-EGFP reporter vector. This reporter plasmid was stably trans-fected into NIH3T3 cells for generation of reporter cell line. When the reporter cell line was infected with E2F-1 together with excess amounts of empty vector, the cells that received the positive modulator were readily identifiable by green fluorescence using FACS. The GFP-positive cells were cloned directly from the cultured cells and expanded in bulk culture. The genomic DNAs from GFP-positive cells were prepared and the CDNA insert in integrated retroviral genome was recovered by PCR using primers annealing to the retroviral vector sequences flanking the insert-cloning site. This system should be useful for efficient screening of expression CDNA libraries in mammalian cells to identify novel upstream regulators for spe-cific genes by one-hybrid interaction.ion.