• Korean Journal of Plant Tissue Culture
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• v.25 no.6
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• pp.519-524
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• 1998

A simple and reliable method to diagnose cucumber green mottle mosaic virus of watermelon in Korea (CGMMV-WK) was determined by RT-PCR, and coat protein gene for CGMMV-WK was cloned. Comparing to a method reported by Lee et al. (1996), the method developed here showed a better RT-PCR reaction. RT-PCR was possible by one step in the PCR reaction mixture that contains 20 pmol of primer, reverse transcriptase (30 unit), RNasin (5 unit) using the crude RNA solution. RT-PCR condition for specifically diagnosing CGMMV-WK was that cDNA was synthesized at 42$^{\circ}C$ for 45 min followed by pre-denaturation at 95$^{\circ}C$ for 2 min, and then PCR reaction was carried out with a programmed condition that consisted of 36 sequential cycles at 96$^{\circ}C$ for 30 sec, 6$0^{\circ}C$ for 30 sec, and 72$^{\circ}C$ for 1 min. A gene encoding the coat protein of CGMMV-WK was cloned and characterized. Nucleotide sequence of coat protein gene of CGMMV-WK shared 98.77% and 99.38% of sequence identity with those of CGMMV-W and CGMMV-SH, respecitvely, however, all of amino acid sequences were same.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.2
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• pp.157-168
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• 2000

Sea urchin S. intermedius occurring in the Korean east coast is a cold water species that belongs to the family Strongylocentrotidae of Echinoidea. Although it is known that there are nine species in the family, species identification criteria, phylogenetic relationships, time and process of evolution of the family members have not been uncovered clearly. In the present study, I tried to find some clues to such problems for S. intermedius by means of DNA sequences. For this, cytochrome c oxidase subunit I (COI), one of the mitochondrial genes that evolve fast and follow maternal inheritance was analyzed. DNA was extracted from the female gonad of S. intermedius, a segment of COI gene amplified by polymerase chain reaction (PCR), and finally a total of 1077 base pair sequence of COI obtained by cloning and sequencing the PCR product. The sequence was compared with homologous genes of other sea urchins and echinoderm species. Phylogenetic trees of the COI gene segment revealed that S. intenedius is a sister species of S. purpuratus which lives along the east coast of the Paciflc. With reference to the fossil records of sea urchins and genetic distances in the molecular phylogenies, it is estimated that the two species were separated about 0.89 million years ago when the earth temperature fluctuated significantly. The current disjunct distribution patterns of the two species and the climate change of the earth at the time of separation suggest that speciation might have occurred by vicariance. The COI gene sequence obtained here now can be used as a molecular character which discerns S. intermedius from the other sea urchin species of Strongylocentrotidae.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.380-387
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• 1997

Phytopathogenic Erwinia carotovora subsp. carotovora (Ecc) LY34 causes plant tissue maceration by secretion of pectinolytic enzymes such as pectate Iyase (PL) existed as multiple isoenzyme form. Genomic DNA from Ecc LY34 was digested with Sau3Al and ligated into the BamHI site of pBluescript ll $SK^+$. Among them, a clone hydrolyzing polypectate was selected and its DNA was digested with BamHI. Through the subsequent subcloning the resulting 3.1 kb fragment, corresponding to a peICI, was subcloned into pLYPA 100. The structural organization of a peICI gene encoding a 374 amino acid residues consists of an open reading frame (ORF) of 1,122 bp commencing with a ATG start codon and followed by a TAA stop codon. PeICI contained a typical prokaryotic signal peptide of 22-amino acid. Since the deduced amino acid sequences of PeICl protein was very similar to those of PelIII of Erwinia carotovora subsp. carotovora, and to those of Pel3 of Erwinia carotovora subsp. atroseptica, and to those of PeIC of Erwinia carotovora subsp. carotovora, it belong to the same family PLbc group. The 374-amino acld PeICI had a calculated Mr of 40,507 and pI of 7.60.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.173-180
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• 2000

The intern1 spacer regions (ISR) between the 16s and 23s $1_RNA$ genes of Aeronzonus iwonii blogroupsobria and A. caviae were investigated by PCR fragment length typing and DNA sequencing. A. iwonii bv.sobria has a speciIic 16s-23s pattern of 2-4 fiagments ranging Goin 479-539 bp, with the exception of thespecies Aeron7onns cmiae, which has 3 fragments ranglog from 470-602 bp. In all of the.4 vei*onii bv. sobr,iaand A, caviae strains examined in this study, the 470-481bp Tragnent, designated TSR-1, invariably contained $tDNA^{uc(GAT)$ and $tDNA^{Ala(TGC)$ in contrast to ISR-2 (513-525 bp). ISR-3 (537-539 bp) and ISR-4 (568-602 bp)containing TEX>$tDNA^{Olu(ITC)$ A stretch of 20 nucleotides (178-197 bp) in the ISR-4 was conserved only wit11mA.caiiue, from which the A. caiiae specific primer, named prAC-F, was designed and used for PCR with aAcaviae coimnon reverse primer A PCR product of 450 bp was apparent alnong I , caiizne strains, but not ii1.4.ijeronii bv. sob~ia strains. The PCR product was oot detected t"-om strains belonging to A. hjili-o~~hila, Ebrio,aud the family Ef\ulcornertei,obncteriaceae. This study provides the first molecular tool for mdentifying the species 8.caviae.ing the species 8. caviae.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.141-147
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• 2017

In this study, a meta-analysis of fecal bacteria in dogs was conducted using 16S rRNA gene sequences that have been recovered from cloning and Sanger sequencing. For this meta-analysis, we retrieved all 16S rRNA gene sequences recovered from fecal bacteria in dogs in the RDP database (Release 11, Update 3). A total of 420 sequences were identified from the RDP database, 42 of which were also recovered from cultured isolates. The 420 sequences were assigned to five phyla, of which Firmicutes was the most predominant phylum, accounting for 55.2% of all 420 sequences. Bacteroidetes was the second most predominant phylum, accounting for 32.1% of the 420 sequences, followed by Actinobacteria (6.4%), Fusobacteria (3.8%), and Proteobacteria (2.4%). The genus Bacteroides within Bacteroidetes was the largest, representing 30.0% of all 420 sequences, while the putative genus Clostridium XI within Firmicutes was the second largest, representing 27.4% of all 420 sequences. A total of 82 operational taxonomic units (OTUs) that are putative species were identified from the retrieved sequences. The results of this study will improve understanding of the diversity of fecal bacteria in dogs and guide future studies on the health and well-being of dogs.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.749-754
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• 2000

PCR primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of the enzymes involved in the biosynthesis of deoxysugar. The PCR product (360 bp) was obtained from Thermus caldophilus GK24. Colony hybridization was carried out to the cosmid library constructed from T. caldophilus GK24 genomic DNA by the PCR product DNA fragment. We isolated a cosmid clone (pSMTC-1) that was subcloned to call pKCB series plasmid (BamHI fragments), partially sequenced and analyzed. pKCB80 (4.2 kb-BamHI DNA fragment) of them showed ORFs that was orfA, orfB, orfC and orfD. The orfABCD gene cluster is the deosysugar biosynthetic gene ; orfA (glucose-1-phosphate thymidylytransferase), orfB (dTDP-D-glucose 4,6-dehydratase), orfC (dTDP-4-keto-L-rhamnose reductase) and orfD (dTDP-4-keto-6-deoxy-D-glucose 3,5-epimerase). The gene cluster that was related in biosynthesis of dTDP-L-rhamnose was also identified by computer analysis, and we proposed that the biosynthetic pathway of deoxysugar analyzed from DNA sequencing of pKCB80 is from D-glucose-1-phosphate, dTDP-D-glucose, dTDP-4-keto-6-deoxy-D-glucose via dTDP-4-keto-L-rhamnose to dTDP-L-rhamnose.

• BMB Reports
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• v.36 no.6
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• pp.545-551
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• 2003

A cDNA of bovine brain glutamate dehydrogenase (GDH) was isolated from a cDNA library by recombinant PCR. The isolated cDNA has an open-reading frame of 1677 nucleotides, which codes for 559 amino acids. The expression of the recombinant bovine brain GDH enzyme was achieved in E. coli. BL21 (DE3) by using the pET-15b expression vector containing a T7 promoter. The recombinant GDH protein was also purified and characterized. The amino acid sequence was found 90% homologous to the human GDH. The molecular mass of the expressed GDH enzyme was estimated as 50 kDa by SDS-PAGE and Western blot using monoclonal antibodies against bovine brain GDH. The kinetic parameters of the expressed recombinant GDH enzymes were quite similar to those of the purified bovine brain GDH. The $K_m$ and $V_{max}$ values for $NAD^+$ were 0.1 mM and $1.08\;{\mu}mol/min/mg$, respectively. The catalytic activities of the recombinant GDH enzymes were inhibited by ATP in a concentration-dependent manner over the range of 10 - $100\;{\mu}M$, whereas, ADP increased the enzyme activity up to 2.3-fold. These results indicate that the recombinant-expressed bovine brain GDH that is produced has biochemical properties that are very similar to those of the purified GDH enzyme.

• The Journal of Korean Society of Virology
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• v.29 no.1
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• pp.45-53
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• 1999

We examined the hepatitis G virus infections among 227 Koreans who were healthy or were suspected of hepatitis and determined the phylogenetic relationship based on a part of the NS-5 region of 5 positive samples. Viral RNA was extracted from sera and cDNA was synthesized and subsequently amplified by RT-PCR (reverse transcription-polymerase chain reaction) or RT-nested PCR using random hexamer and NS-5 specific primers (470-20-1-77F, 470-20-1-211R, HGVNESTFO, HGVNESTRE). Five positives were found to belong to samples of patients showing symptoms of viral hepatitis. Primers used for PCR or nested PCR were derived from the NS-5 region. On the other hand, no amplification was detected using primers derived from the 5'-NCR (G-146F, G-401R). We performed TA cloning and sequencing of 5 amplified fragments, and their sequences were compared with those of foreign isolates of HGV. The phylogenetic analysis using MegAlign programme of DNAstar has shown that the Korean isolates are clustered on the phylogenetic tree. In summary, we confirmed the hepatitis G virus infection in 5 cases out of 12 patients showing the symptoms of viral hepatitis. The phylogenetic analysis of sequences of 5 amplified fragments showed that their relations to each other were closer than those to the foreign HGV isolates reported.

• The Korean Journal of Malacology
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• v.29 no.3
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• pp.171-179
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• 2013

Arginine kinase (ArK) is known to play an important role in most invertebrates the level of ATP by phosphorylation of phosphagens in cell and immuninty in living organisms. ArK has been identified in many kinds of organisms ranging from invertebrate to vertebrate. However, no ArK gene has been cloned and investigated from N. samarangae. This leads us to identify ArK cDNA (NsArK) from the expressed sequence tag (EST) sequencing of N. samarangae. Sequence analysis indicated that the coding region of 1,065 bp contains 355 amino acid residues. Molecular phylogenetic analysis shows that NsArK had very high similarities with mollusca and arthropoda. In an attempt to investigate a potential role of NsArK in the digestive gland of N. samarangae, expression patterns were analyzed. RT-PCR analsysis shows that NsArK mRNA is induced in the rane of 1.2 fold at 6 hr by laminarin when compared with the control. The immunnologial and physiological role of NsArK remains to be further investigated in N. samarangae.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.355-362
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• 2016

The phosphomannomutase/phosphoglucomutase gene (pmm/pgm) of Vibrio anguillarum (the causative agent of fish vibriosis) was cloned, and the open reading frame corresponded to a protein with 446 amino acids. The pmm/pgm gene showed a significant degree of sequence homology with the previously reported genes from V. mimicus, V. vulnificus, V. splendidus, and V. harveyi, with 92.3%, 91.4%, 89.9%, and 89.9% amino acid identity, respectively. By reverse transcriptase-polymerase chain reaction, we found that the pmm/pgm gene was upregulated under cold stress condition. The PMM/PGM protein is known to catalyze the interconversion between mannose-1-phosphate and mannose-6-phosphate or glucose-1-phosphate and glucose-6-phosphate, which are important intermediates for lipopolysaccharide (LPS) biosynthesis. To confirm the role of PMM/PGM in the LPS biosynthetic pathway, we constructed a knock out mutant by homologous recombination. The respective LPSs were isolated from the V. anguillarum wild-type and mutant strains, and changes were compared by subjecting them to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Based on the different patterns of the LPSs, we expect the pmm/pgm gene to have an important role in LPS biosynthesis. The pmm/pgm-deficient mutant of V. anguillarum will contribute to further studies about the role of LPS in V. anguillarum pathogenesis.