• The Plant Pathology Journal
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• 제34권1호
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• pp.59-64
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• 2018

Bacteriophages of Acidovorax citrulli, the causal agent of bacterial fruit blotch, were isolated from 39 watermelon, pumpkin, and cucumber leaf samples collected from various regions of Korea and tested against 18 A. citrulli strains. Among the six phages isolated, ACP17 forms the largest plaque, and exhibits the morphology of phages in the Myoviridae family with a head diameter of $100{\pm}5nm$ and tail length of $150{\pm}5nm$. ACP17 has eclipse and latent periods of $25{\pm}5min$ and $50{\pm}5min$, respectively, and a burst size of 120. The genome of ACP17 is 156,281 base pairs with a G + C content of 58.7%, 263 open reading frames, and 4 transfer RNA genes. Blast search and phylogenetic analysis of the major capsid protein showed that ACP17 has limited homology to two Stentrophomonas phages, suggesting that ACP17 is a new type of Myoviridae isolated from A. citrulli.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.625-628
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• 2001

토양으로부터 특이적인 광학 이성질체에 활성을 갖는 두 효소원을 선별한 후, 동정하여 Pseudomonas sp. S34와 B. stearothermophilus JY144로 명명하였고, genecloning과 sequencing을 통해 유전자의 특성 및 관련효소들과의 유연관계를 규명하였다. 규명된 정보의 분석과 비교를 통해 ketoprofen ethyl ester에 활성을 갖는 효소들의 구조적 특성을 추론할 수 있었고, 이를 바탕으로 발현시스템을 구축하였다. 대량생산된 효소를 활용한 반응의 결과 높은 수율과 순도를 갖는 각각의 광학이성질체를 경제적으로 생산할 수 있었다.

• Genomics & Informatics
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• 제2권3호
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• pp.134-141
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• 2004

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide and a typical hypervascular tumor. Therefore, it is important to find factors related to angiogenesis in the process of HCC malignancy. In order to find angiogenesis-related factors in HCC, we used combined methods of in silico prediction and an experimental assay. We analyzed 1457 genes extracted from cDNA microarray of HCC patients by text-mining, sequence similarity search and domain analysis. As a result, we predicted that 16 genes were likely to be involved in angiogenesis and then the effects of these genes were confirmed by hypoxia response element(HRE)-luciferase assay. For instant, we classified osteopontin into a potent angiogenic factor and coagulation factor XII into a significant anti­angiogenic factor. Collectively, we suggest that using a combination of in silico prediction and experimental approaches, we can identify HCC-specific angiogenesis­related factors effectively and rapidly.

• Genomics & Informatics
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• 제10권1호
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• pp.9-15
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• 2012

Horizontal gene transfer (HGT) is the movement of genetic material between kingdoms and is considered to play a positive role in adaptation. $Cryptosporidium$ $parvum$ is a parasitic protozoan that causes an infectious disease. Its genome sequencing reported 14 bacteria-like proteins in the nuclear genome. Among them, cgd2_1810, which has been annotated as CysQ, a sulfite synthesis pathway protein, is listed as one of the candidates of genes horizontally transferred from bacterial origin. In this report, we examined this issue using phylogenetic analysis. Our BLAST search showed that $C.$ $parvum$ CysQ protein had the highest similarity with that of proteobacteria. Analysis with NCBI's Conserved Domain Tree showed phylogenetic incongruence, in that $C.$ $parvum$ CysQ protein was located within a branch of proteobacteria in the cd01638 domain, a bacterial member of the inositol monophosphatase family. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, the sulfate assimilation pathway, where CysQ plays an important role, is well conserved in most eukaryotes as well as prokaryotes. However, the Apicomplexa, including $C.$ $parvum$, largely lack orthologous genes of the pathway, suggesting its loss in those protozoan lineages. Therefore, we conclude that $C.$ $parvum$ regained cysQ from proteobacteria by HGT, although its functional role is elusive.

• Parasites, Hosts and Diseases
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• 제39권2호
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• pp.151-160
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• 2001

Randomly selected 435 clones from Acanthamoeba healyi cDNA library were sequenced and a total of 387 expressed sequence tags (ESTs) had been generated. Based on the results of BLAST search, 130 clones (34.4%) were identified as the genes enconding surface Proteins , enzymes for DNA, energy Production or other metabolism, kinases and phosphatases, protease, proteins for signal transduction, structural and cytoskeletal proteins, cell cycle related proteins, transcription factors, transcription and translational machineries, and transporter proteins. Most of the genes (88.5%) are newly identified in the genus Acanthamoeba. Although 15 clones matched the genes of Acanthamoeba located in the public databases, twelve clones were actin gene which was the most frequently expressed gene in this study. These ESTs of Acanthamoeba would give valuable information to study the organism as a model system for biological investigations such as cytoskeleton or cell movement, signal transduction, transcriptional and translational regulations. These results would also provide clues to elucidate factors for pathogenesis in human granulomatous amoebic encephalitis or keratitis by Acanthamoeba.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.48-48
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• 2003

본 실험은 spermatogonia 단계에 발현하는 유전자를 찾기 위하여 suppression subtractive hybridization를 수행하였다. 기존에 mouse에서는 spermatogonia 특이적인 유전자들이 밝혀져 있기 때문에 pig에 특이적인 유전자를 찾기 위하여 pig 250days testis와 pig 60days testis를 재료로 하여 실험하였다. SSH를 통하여 254days testis에 특이적으로 발현되는 후보유전자를 7개 찾았고 25days testis와 60days testis 의 Northern blot을 통하여 25days에 과발현하고 60days에 발현의 양이 대폭 줄어드는 spermatogonia 유전자로 생각되는 후보유전자 2개를 선택하여 pig tissue northern blot, genomic DNA southern blot, RT-PCR 그리고 In-situ hybridization을 수행하였다. Tissue northern blot과 RT-PCR을 통하여 후보자 1번은 간과 폐, 난소, 정소에서 발현하고, 후보유전자 15번은 난소와 정소에서만 특이적으로 발현함을 알았다. DNA sequence analysis와 NCBI Blast search를 통하여 후보자 1번은 다른 종에서 밝혀진 유전자였고 후보유전자 15번은 어느 종에서도 밝혀지지 않은 새로운 유전자였다. Degenerated primer를 통하여 후보자 1번의 pig full sequence를 밝히고 NCBI에 등록하였다. 그리고 In-situ hybridization을 통하여 후보유전자득이 20일째 testis의 Leydic cell에서 많이 발현되고 adult testis에서는 발현이 감소하는 결과를 얻었다. 이것으로 보아 위의 두 후보유전자는 spermatogonia에 직접 관련된 유전자이기 보다는 spermatogonia의 발달에 영향을 주는 leydic cell 특이발현을 가진 유전자로 사료되어진다.

• Journal of Microbiology and Biotechnology
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• 제17권3호
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• pp.481-489
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• 2007

[ $\alpha$ ]-L-Arabinofuranosidases (AFases; EC 3.2.1.55) are exo-type enzymes, which hydrolyze terminal nonreducing arabinose residues from various polysaccharides such as arabinan and arabinoxylan. Genome-wide BLAST search showed that various bacterial strains possess the putative AFase genes with well-conserved motif sequences at the nucleotide and amino acid sequence levels. In this study, two sets of degenerate PCR primers were designed and tested to detect putative AFase genes, based on their three highly conserved amino acid blocks (PGGNFV, GNEMDG; and DEWNVW). Among 20 Bacillus-associated species, 13 species were revealed to have putative AFase genes in their genome and they share over 67% of amino acid identities with each other. Based on the partial sequence obtained from an isolate, an AFase from Geobacillus sp. was cloned and expressed in E. coli. Enzymatic characterization has verified that the resulting enzyme corresponds to a typical AFase. Accordingly, degenerate PCR primers developed in this work can be used for fast, easy, and specific detection and isolation of putative AFase genes from bacterial cells.

• Journal of Ecology and Environment
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• 제34권3호
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• pp.323-331
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• 2011

Biodiversity and the community composition of micro-eukaryotic organisms were investigated in the Upo wetland in Korea using molecular analysis. Molecular identification was performed using cytochrome oxidase I (COI) and small subunit ribosomal DNA (SSU rDNA). The genomic DNA was isolated directly from soil samples. The COI and SSU rDNA regions were amplified using universal primers and then sequenced after cloning. In a similarity search of the obtained sequences with BLAST in the Genbank database, the closely related sequences from NCBI were used to identify the amplified sequences. A total of six eukaryotic groups (Annelida, Arthropoda, Rotifera, Chlorophyta, Bacillariophyta, and Stramenopiles) with COI and six groups (Annelida, Arthropoda, Rotifera, Alveolata, Fungi, and Apicomplexa) with SSU rDNA genes were determined in the Upo wetland. Among 38 taxa in 20 genera, which are closely related to the amplified sequences, 10 genera (50%) were newly reported in Korea and five genera (25%) were shown to be distributed in the Upo wetland. This approach is applicable to the development of an efficient method for monitoring biodiversity without traditional taxonomic processes and is expected to produce more accurate results in depositing molecular barcode data in the near future.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.243-246
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• 2005

A novel esterase showing high enantioselectivity to (S)-ketoprofen ethyl ester was selected from fosmid environmental DNA library which is provided by Microbial Genomic & Applications Center. As a result of Blast search, the gene wasn't registerated in Gene Bank yet. And as we know, conserved domain region of esterase , G-X-S-X-G, wasn't discovered.$^{4)}$ And it is similar to Beta-lactamase. The DNA sequence of cloned esterase include an open reading frame consisting of 1170 bp, designated as EST-Y29, encoding a protein of 389 amino acids with a molecular mass of about 42.8 kDa. And amino acid sequence analysis revealed only a few identity (28%) to tile known esterases/lipases in the databases containing the conserved sequence motifs of esterases/lipases. when being comparison to other esterase revealed , this enzyme seems to be classified as a new member of esterase family. EST-Y29 was functionally overexpressed in a soluble form in E. coli with maximum conversion yield of (S)-ketoprofen at $65^{\circ}C$. This study demonstrates that functional screening combined with the sequential uses of restriction enzymes to exclude already known enzymes is a useful approach for isolating novel enzyme from a metagenome.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권1호
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• pp.23-26
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• 2000

In order to develop the specific genetic marker for Korean native cattle (Hanwoo), randomly amplified polymorphic DNA (RAPD) analysis of 6 different cattle breeds was attempted by using 38 decamer primers. In comparison of RAPD patterns, two distinctive DNA bands specific for Hanwoo were detected. One was 296 bp of DNA fragment found to be specific only for female Hanwoo when primer GTCCACACGG was employed. In individual analysis of this RAPD marker was observed only in female individuals with the possibility of $85.3\%$. The other was 521 bp of RAPD marker amplified using TCGGCGATAG and AGCCAGCGAA primers, which showed $83.0\%$ of genetic frequency in 85 male and 68 female individuals tested. Nucleotide sequencing of these genetic markers revealed that 296 bp marker has a short micro satellite-like sequence, ACCACCACAC, and a tandem repeat sequence of microsatellite GAAAAATG in the determined sequence. Two distinctive tandem repeats of microsatellite sequences, MC and GAAGA, were also appeared in 521 bp DNA marker. In BLAST search, any gene having high homology with these markers was not found.