• Journal of Microbiology
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• v.45 no.2
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• pp.153-157
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• 2007

5-enolpyruvylshikimate-3-phosphate synthase (EPSP synthase, EC 2.5.1.19) is the sixth enzyme in the shikimate pathway which is essential for the synthesis of aromatic amino acids and many secondary metabolites. The enzyme is widely involved in glyphosate tolerant transgenic plants because it is the primary target of the nonselective herbicide glyphosate. In this study, the Dunaliella salina EPSP synthase gene was cloned by RT-PCR approach. It contains an open reading frame encoding a protein of 514 amino acids with a calculated molecular weight of 54.6 KDa. The derived amino acid sequence showed high homology with other EPSP synthases. The Dunaliella salina EPSP synthase gene was expressed in Escherichia coli and the recombinant EPSP synthase were identified by functional complementation assay.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.222-229
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• 2006

Twenty-two isolates of Fusarium oxysporum f. sp. fragariae were obtained from diseased strawberry plants and their characteristics were investigated by vegetative compatibility group (VCG), random amplified polymorphic DNA (RAPD), and pathogenicity. Three major VCGs (A, B, and C) and one incompatible group were identified by nitrate reductase complementation test. The virulence pattern of the 22 isolates was studied in relation to four cultivars including Dochiodome, Red-pearl, Maehyang and Akihime. RAPD markers were used to determine genetic relationship, and created three major clusters among the 22 isolates of F. oxysporum f. sp. fragariae. Isolates belong to VCG-C were strongly pathogenic, and relatively high correlation was existed among VCG and RAPD, and virulence. In addition, VCG and RAPD pattern between pathogenic and non-pathogenic isolates were distinctly different.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.397-403
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• 2008

Nikkomycins are a group of peptidyl nucleoside antibiotics with potent fungicidal, insecticidal, and acaricidal activities. sanN was cloned from the partial genomic library of Streptomyces ansochromogenes 7100. Gene disruption and complementation analysis demonstrated that sanN is essential for nikkomycin biosynthesis in S. ansochromogenes. Primer extension assay indicated that sanN is transcribed from two promoters (sanN-P1 and sanN-P2), and sanN-P2 plays a more important role in nikkomycin biosynthesis. Purified recombinant SanN acts as a dehydrogenase to convert benzoate-CoA to benzaldehyde in a random-order mechanism in vitro, with respective $K_{cat}/K_m$$ values of $3.8mM^{-1}s^{-1}\;and\;12.0mM^{-1}s^{-1}$ toward benzoate-CoA and NADH, suggesting that SanN catalyzes the formation of picolinaldehyde during biosynthesis of nikkomycin X and Z components in the wild-type stain. These data would facilitate us to understand the biosynthetic pathway of nikkomycins and to consider the combinatorial synthesis of novel antibiotic derivatives.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.141-150
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• 1996

본 연구에서는 $CD4^+$ T 세포를 일회성으로 감염시킬 수 있고 $CD4^+$ T 세포에 HIV-1 envelope 유전자를 전달할 수 있는 바이러스 입자를 생산하는 HIV-1 complementation system을 개발하였고 이 system을 이용하여 $CD4^+$ T 세포에 선택적으로 HIV-1 envelope 당단백질을 발현시켰다. 이 system은 Gag/Gag-Pol expressor와 Env expressor로 구성되어있다. Gag/Gag-Pol expressor는 바이러스 입자 생산에 필요한 구조단백질과 기능단백질을 발현시키지만 packaging signal이 결핍되어 바이러스 입자로 유전자가 들어가지 못하도록 제조되었다. Env expressor는 Tat, Rev와 envelope 당단백질을 발현시키고 packaging signal을 갖고 있어 바이러스 입자로 envelope 유전자가 들어가도록 제조되었다. Gag/Gag-Pol expressor로부터 Gag와 Gag-Pol의 발현은 Rev 단백질을 요구하였고 Env expressor로부터 Rev 단백질 이 제공될 때 Gag와 Gag-Pol 단백질은 효율적으로 발현되었다. Gag/Gag-Pol과 Env expressor로 cotransfection된 COS-1 세포에서 $CD4^+$ T 세포를 일회성으로 감염시킬 수 있는 바이러스 입자가 생산되었다. 생산된 바이러스 입자는 $CD4^+$ T 세포에 HIV-1 envelope 유전자를 전달하여 envelope 당단백질을 발현시켰고 복제 가능한 자손 바이러스의 생성을 유도하지 못하였다. 본 연구에서 개발된 방법은 $CD4^+$ T 세포에서 envelope 당단백질의 기능을 분석하고 관심 있는 유전자를 $CD4^+$ T 세포에 전달하는 바이러스 입자의 생산에 이용할 수 있다.

• The Plant Pathology Journal
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• v.20 no.3
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• pp.206-211
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• 2004

Transgenic Nicotiana benthamiana plants harboring coat protein (CP) gene of Zucchini green mottle mosaic virus (ZGMMV) were generated for virus-resistant screening and complementation analysis of related viruses for environmental safety assessment (SA) of living modified organism (LMO) purposes. Transformation of leaf disc of N.benthamiana was performed by using Agrobacterium-mediated method and the pZGC-PPGA748 containing the ZGMMV CP and NPTII genes. Two kinds of transgenic homozygous groups, virus-resistant and virus-susceptible N.benthamiana lines, were obtained by screening of challenging homologous virus for Tl generations. These two pathologically different lines can be useful for host-virus interactions and LMO environmental SA.

• Journal of Plant Biotechnology
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• v.39 no.2
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• pp.106-113
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• 2012

Glycolysis is responsible for the conversion of glucose into pyruvate and for supplying reducing power and several metabolites. Fructose-1,6-bisphosphate aldolase (AtFBA1), a central enzyme in the glycolysis pathway, was isolated by functional complementation of the salt-sensitive phenotype of a calcineurin (CaN)-deficient yeast mutant. Under high salinity conditions, aldolase activity and the concentration of NADH were compromised. However, expression of AtFBA1 maintained aldolase activity and the NADH level in yeast cells. AtFBA1 shares a high degree of sequence identity with known class I type aldolases, and its expression was negatively regulated by stress conditions including NaCl. The fusion protein GFP-AtFBA1 was localized in the cytosol of Arabidopsis protoplasts. The seed germination and root elongation of AtFBA1 knock-out plants exhibited sensitivity to ABA and salt stress. These results indicate that AtFBA1 expression and aldolase activity is important for stress tolerance in yeast and plants.

• Journal of Environmental Science International
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• v.18 no.8
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• pp.847-855
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• 2009

As a part of effort to establish an offshore wind resource assessment system of the Korean Peninsula, a numeric wind simulation using mesoscale climate model MM5 and a spatial distribution of offshore wind extracted from SAR remote-sensing satellite image is compared and analyzed. According to the analyzed results, the numeric wind simulation is found to have wind speed over predication tendency at the coastal sea area. Therefore, it is determined that a high-resolution wind simulation is required for complicated coastal landforms. The two methods are verified as useful ways to identify the spatial distribution of offshore wind by mutual complementation and if the meteor-statistical comparative analysis is performed in the future using adequate number of satellite images, it is expected to derive a general methodology enabling systematic validation and correction of the numeric wind simulation.

• BMB Reports
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• v.30 no.3
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• pp.167-172
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• 1997

The yeast Saccharomyces cerevisiae, mutant CH117, shows a drug-hypersensitivity (dhs) to cycloheximide, bleomycin, actinomycin D, 5-fluorouracil. nystatin, nigericin and several other antibiotics. CH 117 was also temperature-sensitive (ts). being unable to grow at $37^{\circ}C$ and secreted more invertase and acid phosphatase into the medium than the parent yeast. CH117 grows very slowly and the cell shape is somewhat larger and more sensitive to zymolyase than the wild type cells. Light microscopic and electron microscopic observation also revealed abnormality of the mutant cell wall. These characteristics indicate that CH117 has a defect in an essential component of the cell surface and that the cell wall which performs barrier functions has become leaky in the mutant. We screened a genomic library of wild type yeast for clones that can complement the mutation of CH117. A plasmid, pCHX1, with an insert of 3.6 kilobases (kbs) could complement the dhs and ts of CH117. Deletion and subcloning of the 3.6 kb insert showed that a gene for the complementation of mutant phenotypes was located in 1.9 kbs Puvll-Hindlll fragment.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.227-230
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• 2000

A total of 90 isolates of Fusarium oxysporum f.sp. melonis, the causal agent of oriental melon (Cucumis melo var. makuwa) wilt, was isolated from symptomatic tissues of oriental melon from 4 provinces in Korea. These isolates were grouped into vegetative compatibility groups (VCGs) by demonstrating heterokaryosis through complementation using nitrate nonutilizing (nit) mutants. No self-incompatibility was observed in any of isolates. All isolates were grouped into 3 VCGs ; A, B, and C. iSOLATES BELONGING TO VCG A and VCG B accounted for 87% and 91% of the fungal population collected in 1991 and 1993, respectively. As the increment of cultivation period in the same field, the proportion of isolates belonging to VCG B increased whereas that of isolates belonging to VCG A decreased. Mean virulence of a total population increased as the increment of cultivation period in the same field. Isolates belonging to VCG B showed the highest increment of virulence. These data suggest that replanting of a host plant in the same field may cause increase of virulence in the pathogens. Furthermore, virulence of F. oxysporum f.sp. melonis isolates is related to the VCGs.

• Environmental Mutagens and Carcinogens
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• v.17 no.1
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• pp.1-6
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• 1997

The RAD4 gene of Saccharomyces cerevisiae is essential for the incision step of UV-induced excision repair. A yeast RAD4 gene has been previously isolated by functional complementation. In order to identify the RAD4 homologous gene from fungus Coprinus cinereus, we have constructed cosmid libraries from electrophoretically separated chromosomes of the C. cinereus. The 13 C. cinereus chromosomes were resolved by pulse-field gel electrophoresis, hybridized with S. cerevisiae RAD4 DNA, and then isolated homologous C. cinereus chromosome. The insert DNA of the RAD4 homolog was contained 3.2 kb. Here, we report the partial cloning and characterization of fungus C. cinereus homolog of yeast RAD4 gene. Southern blot analysis confirmed that C. cinereus contains the sequence homologous DNA to RAD4 gene and this gene exists as a single copy in C. cinereus genome. When total RNA isolated from C. cinereus cells was hybridized with the 1.2 kb PvuII DNA fragment of the S. cerevisiae RAD4 gene, a 2.5 kb of transcript was detected. The level of the transcript did not increase upon UV-irradiation, suggesting that the RAD4 homologous gene in C. cinereus is not UV-inducible.