• KSBB Journal
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• v.13 no.6
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• pp.662-668
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• 1998

Viruses belonging to the Hantavirus genus cause two acute severe illness in humans, i.e., Haemorrhagic Fever with Renal Syndrome (HFRS) and Hantavirus Pulmonary Syndrome(HPS). Among them, Hantaan virus is one of the most important viruses causing HFRS. Recombinant expression vectors, pKK-NP and pET-NP, with Hantaan viral nucleocapsid gene were constructed, and used to transform Eschericia coli BL21(DE3). Stability of the vectors in the host strain, and effects of some environmental conditions on the expression of nucleocapsid gene were studied. Expression vector, pKK-NP, was very unstable, and the expression level of nucleocapsid gene was very low compared to that of pET-NP. BL21(pET-NP) produced about 100 mg of N protein per liter of culture broth. Induction time did not show any significant difference on the expression level of nucleocapsid gen and cell growth. BL21(pET-NP) culture at 35$^{\circ}C$ showed a little higher expression level than at 30$^{\circ}C$ during growth phase, but reached to the same level at stationary phase. Total expression level was proportional to supplemented glucose concentration of media up to 0.5% along with cell growth, but expression level per unit cell mass was inversely proportional to glucose concentration and maximal when glucose was not supplemented at all.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.114-119
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• 1990

A yeast chromosomal superkiller gene (SK13) was cloned and expressed in $ski3^{-}$ Saccharomyces cerevisiae strains. The gene was fused to the structural region of E. coli lacZ gene at its C-terminus in a yeast-E. coli shuttle vector, pSR605. The fused gene complemented $ski3^{-}$ strains with SK13 activity and the quantitative level of expression was measured as determined by assaying $\beta$-galactosidase activity. The SDS-polyacrylamide gel electrophoresis and the Western blot analysis of this fused protein showed the immuno-reacted bands with a protein of the estimated molecular size (ca.250Kd).

• BMB Reports
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• v.32 no.5
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• pp.436-439
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• 1999

Shigella sonnei is an important cause of human enteric infections. S. sonnei KNIH104S was previously reported to be isolated from Korean shigellosis patients. We cloned a 2.8-kb KpnI fragment containing the recA gene encoding a recombinase from the chromosomal DNA of S. sonnei KNIH104S. This recombinant plasmid was named pRAK28. E. coli HB101, a recA mutant, cannot grow on Luria-Bertani medium in the presence of the alkylating agent methylmethane sulfonate, however, E. coli HB101 harboring pRAK28 was found to grow on this medium. As far as we know, we are the first to sequence the recA gene from S. sonnei. This gene is composed of 1062 base pairs with an ATG initiation codon and a TAA termination codon. Nucleotide sequence comparison of the S. sonnei recA gene exhibited 99.7% and 99.5% identity with those of S. flexneri and E. coli, respectively.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.21-25
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• 2000

We have got several clones from Serratia marcescens which stimulated the cells to use maltose as a carbon source in Escherichia. coli TP2139 ( lac, crp). One of the cloned genes, pCKB17, was further analyzed. In order to find whether the increased expression of the gent was under the direction of maltose metabolism, we constructed several recombinant subclones. We have found that the clone, pCKB17AV, codes maltose metabolism stimulation(mms) gene. E. coli transformed with the cloned gene showed increase in the activity of maltose utilzation, The recombinant proteins expressed by multicopy and induction with IPTG, one polypeptide of 29-kDa, was confirmed by SDS-PAGE. The overexpression of maltose-binding proter protein in the presence of mms gene was confirmed by Western blot analysis. Southern hybridization analysis confirmed that the cloned DNA fragment was originated from S. marcescens chromosomal DNA.

• Journal of Microbiology
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• v.34 no.3
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• pp.248-254
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• 1996

$cdc103^+$ gene in Schizosaccharomyces pombe which is similar to the CDC3 gene in Saccharomyces cerevisiae was cloned and sequenced. Comparison of the predicted amino acid sequences of $cdc103^+$ and CDC3 revealed that they share significant similarity (43% identity and 56% identity or similarity) to each other. The gene product of CDC3 in S. cerevisiae is known to be a highly ordered ring of filaments that lies just inside the cytoplasmic membrane in the region of the mother-bud neck. In order to characterize the gene product of $cdc103^+$ in Schizosaccharomyces pombe, fusion proteins were used to generate the polyclonal antibodies specific for the gene product (cdc103p). In immunofluorescence experiments, these antibodies decorate the region of the septum formation as a double ring structure late in the cell division cycle.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.145-150
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• 2001

This study was conducted to obtain the transformed birdsfoot trefoil (Lotus corniculatus L.) plants with BcHSP17.6 gene using Agrobacterium turnefaciens LBA4404 and we confirmed transformed gene from the regenerated birdsfoot trefoil plants. The expression vector, pBKH4 vector, harboring BcHSP17.6 gene was used for production of transgenic birdsfoot trefoil plants. The callus of birdsfoot trefoil was cocultivated with Agrobacteriurn turnefaciens and transformed calli were selected on kanamycin-containing SH-kc medium to regenerate into plants. The transformed birdsfoot trefoil plants were produced 4 momths after cultivation on BOi2Y medium. The transgenic birdsfoot trefoil plants were analyzed by isolation of genomic DNA and genomic Southern hybridization using a -32P labelled BcHSPl7.6 fragments. (Key words : Birdsfoot trefoil, Transgenic plant. BcHSP17.6 gene, Callus induction, Plant regeneration)

• The Journal of Korean Society of Virology
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• v.28 no.4
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• pp.295-302
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• 1998

The RNA genome of poliovirus encodes a long polyprotein precursor and this polyprotein is cleaved proteolytically by viral protease to yield mature proteins. The mature proteins derived from the P1 polyprotein precursor are the component of capsids. To further delineate the process of capsid assembly and encapsidation, in a first attempt, a cell line which expresses the authentic P1 polyprotein was established. CV-1 cells were transfected with the pRCRSVS1P1 plasmid DNA which contains 5'ncr sequences, whole authentic capsid gene of poliovirus and neomycin resistance gene. These cells were treated with G418 for 3 months, and eventually G418 resistant cells were selected and formed colonies. Each colony was picked and grown in the media containing G418. DNA analysis indicated that 1 of 13 neomycin resistant cell lines (R2-18) contains whole poliovirus P1 capsid gene segment which was incorporated into the genome. Immuneprecipitation of cell lysates with sera from rabbit immunized with inactivateded Sabin type 1 particles demonstrated the constitutive expression of the poliovirus P1 capsid protein from R2-18.

• Genomics & Informatics
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• v.5 no.1
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• pp.6-9
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• 2007

An RNase P ribozyme library has been developed as a tool for functional genomics studies. Each clone of this library contains a random 18-mer and the sequence of M1 RNA, the catalytic subunit of RNase P. Repression of target gene expression is thus achieved by the complementary binding of mRNA to the random guide sequence and the successive target cleavage via M1 RNA. Cellular expression of the ribozyme expression was confirmed, and EGFP mRNA was used as a model to demonstrate that the RNase P ribozyme expression system can inhibit the target gene expression. The constructed RNase P ribozyme library has a complexity of $1.4\times10^7$. This novel library system should become a useful in functional genomics, to identify novel gene functions in mammalian cells.

• Mycobiology
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• v.33 no.2
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• pp.113-117
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• 2005

In this study, a total of 300 isolates of Penicillium and related teleomorphic genera were collected from soils of 17 locations in Korea from April to May, 2004. Ninety four isolates were identified as the species of Penicillium subgenus Furcatum based on cultural and morphological characteristics and ${\beta}-tubulin$ gene sequences. Among the specie's, Korean isolates of P. brasilianum Bat. and P. daleae K. M. Zalessky were phylogenetically identical to the reference species based on DNA sequence of the ${\beta}-tubulin$ gene. Here we described and illustrated P. brasilianum and P. daleae that are new in Korea.

• Journal of Plant Biotechnology
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• v.2 no.2
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• pp.101-108
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• 2000

The liverwort Pellia borealis is a diploid, monoecious, allopolypliod species (n=18) that as it was postulated, originated after hybridization and duplication of chromosome sets of two cryptic species: Pellia epiphylta-species N (n=9) and Pellia epiphylla-species 5 (n=9). Our recent results have supported the allopolyploid origin of P.borealis. We have shown that the nuclear genome of P.borealis consists of two nuclear genomes: one derived from P.epiphylla-species N and the other from P.epiphylla-species 5. In this paper we show the origin of chloroplast and mitochondrial genomes in an allopolyploid species P.borealis. To our knowledge there is no information concerning the way of mitochondria and chloroplast inheritance in Brophyta. Using an allopolyploid species of p. borealis as a model species we have decided to look into chloroplast and mitochondrial genomes of P.borealis, P.epiphylla-species N and P.epiphylla-species S for nucleotide sequences that would allow us to differentiate between both cryptic species and to identify the origin of organelle genomes in the alloploid species. We have amplified and sequenced a chloroplast $tRNA^{Leu}$ gene (anticodon UAA) containing an intron that has shown to be highly variable in a nucleotide sequence and used for plant population genetics. Unfortunately these sequences were identical in all three liverwort species tested. The analysis of the nucleotide sequence of chloroplast, an intron containing $tRNA^{Gly}$ (anticodon UCC) genes, gave expected results: the intron nucleotide sequence was identical in the case of both P.borealis and P.epiphyllaspecies N, while the sequence obtained from P.epiphyllasperies S was different in several nucleotide positions. These results were confirmed by the nucleotide sequence of another chloroplast molecular marker the chloroplast, an intron-contaning $tRNA^{Lys}$ gene (anticodon UUU). We have also sequenced mitochondrial, an intron-containing $tRNA^{Ser}$ gene (anticodon GCU) in all three liverwort species. In this case we found that, as in the case of the chloroplast genome, P.borealis mitochondrial genome was inherited from P.epiphylla-species N. On the basis of our results we claim that both organelle genomes of P.borealis derived from P.epiphylla-species N.