• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.870-872
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• 1999

The ubiquinone and G+C contents of the bioflocculant-producing fungus, a new Aspergillus strain, were detennined using high-perfonnance liquid chromatography. The internal transcribed spacers 1 and 2 (ITS1 and ITS2), and the 5.8S ribosomal DNA (rDNA) of the strain were amplified and sequenced. The strain contained ubiquinone-l0($H_2$)as a major quinone and the G+C content was 49 mol%. A phylogenetic analysis of the ITS regions indicated that the strain belonged to the genus Aspergillus according to its previously classified morphological characteristics. Based on a sequence homology search, the strain was most closely related to Petromyces muricatus (anamorph, A. muricatus; accession number, AJ005674). The sequence of a new Aspergillus strain in ITS1 and ITS2, and 5.8S rDNA showed 97% homology to P. muricatus. Therefore, the strain is believed to be a new bioflocculant-producing Aspergillus strain.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.41-49
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• 2009

Random amplified polymorphic DNA (RAPD) marker and sequence analyses of the internal transcribed spacer (ITS) region of ribosomal DNA were used to assess phylogenetic relationships of four Korean oyster species. The average number of species-specific markers identified from five universal rice primers (URPs) by RAPD-PCR was 1.8 for Crassostrea gigas, 3.2 for C. nippona, 3.6 for C. ariakensis, and 4.6 for Ostrea denselamellosa. The length of the ITS (ITS1-5.8S-ITS2) region ranged from 1,001 to 1,206 bp (ITS1, 426-518 bp; 5.8S, 157 bp; and ITS2, 418-536 bp), while the GC content ranged from 55.5-61.1% (ITS1, 56.8-61.8%; 5.8S, 56-57.3%; and ITS2, 54.1-62.2%). A phylogenetic analysis of the oysters based on our RAPD, ITS1, and ITS2 sequence data revealed a close relationship between C. gigas and C. nippona and a distant relationship between the genera Crassostrea and Ostrea. Our results indicated that RAPD and ITS sequence analysis was a useful tool for the elucidation of phylogenetic relationships and for the selection of species-specific markers in Korean oysters.

• The Korea Journal of Herbology
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• v.30 no.3
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• pp.41-47
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• 2015

Objectives : Due to the morphological similarity of the pericarp and description of multi-species in National Pharmacopoeia of Korea and China, the Zanthoxylum Pericarpium is difficult to authenticate adulterant in species levels. Therefore, we introduced the sequence analysis of DNA barcode and identification of single nucleotide polymorphism(SNP) to establish a reliable tool for the distinction of Zanthoxylum Pericarpium from its adulterants. Methods : To analyze DNA barcode region, genomic DNA was extracted from twenty-four specimens of authentic Zanthoxylum species and inauthentic adulterant and the individual internal transcribed spacer regions (rDNA-ITS and ITS2) of nuclear ribosomal RNA gene were amplified using ITS1, ITS2-S2F, and ITS4 primer. For identification of species-specific sequences, a comparative analysis was performed using entire DNA barcode sequences. Results : In comparison of four Zanthoxylum ITS2 sequences, we identified 16, 4, 6, and 4 distinct species-specific nucleotides enough to distinguish Z. schinifolium, Z. bungeanum, Z. piperitum, and Z. simulans, respectively. The sequence differences were available genetic marker to discriminate four species. Futhermore, phylogenetic relationship revealed a clear classification between different Zanthoxylum species showing 4 different clusters. These results indicated that comparative analysis of ITS2 DNA barcode was an useful genetic marker to authenticate Zanthoxylum Pericarpium in species levels. Conclusions : The marker nucleotides, enough to distinguish Z. schinifolium, Z. piperitum, Z. bungeanum, and Z. simulans, were obtained at 30 SNP marker nucleotides from ITS2 sequences. These differences could be used to authenticate official Zanthoxylum Pericarpium from its adulterants as well as discriminating each four species.

• Fisheries and Aquatic Sciences
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• v.13 no.4
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• pp.272-277
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• 2010

Seagrasses are marine angiosperms of ecological importance in providing shelter and food to aquatic species as well as maintaining the carbon cycle on earth. Phyllospadix iwatensis is a seagrass of the family Zosteraceae and is distributed along the eastern coast of Korea. The nucleotide sequences of P. iwatensis nuclear genes encoding 18S ribosomal RNA (rRNA) and internal transcribed spacer-1 (ITS-1) were determined for molecular phylogenetic analysis. Genomic DNA was isolated from P. iwatensis and used for PCR amplification of 18S rRNA and ITS-1. Examination of the 18S rRNA sequence of P. iwatensis showed a close (99% similarity) relationship to Zostera noltii, another genus of Zosteraceae, but a distant (84% similarity) evolutionary relationship to other macroalgal Laminariales species. Further discrepancies found in ITS-1 nucleotide sequences between closely related species indicate that the sequence information could be used for species identification.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.186-191
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• 1994

The origin of the leading strand replication (ori) and of lagging strand replication (M-O) of R-plasmid pSBK203 was identified and its base sequence was determined. About 50 bp of ori sequence residues overlapped with the structural gene of rep. Sequence comparison reveals that pSBK-ori shares obvious identities with those of pT181 family and consists of two regions, one is conserved and the other is variable region. Of two palindrome sequence located one after another in upstream region of rep gene, palA' instead of palA which shares sequence homology with diverse family of plasmids such as pOX6, pC194, and pE194 seems to act as a signal for conversion of primarily replicated ssDNA to dsDNA (minus origin (M-O)).

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.346-361
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• 2022

Food poisoning accidents caused by poisonous plants occur every year. As certain poisonous plants are mistaken for edible plants causing food poisoning, accurate species identification of poisonous plants is required. DNA barcodes suitable for species identification of poisonous plants and database that can be used for accurate species identification are necessary for their use in forensic cases. In this study, species identification of 19 poisonous plants native to Jeju Island using seven DNA barcodes (trnH-psbA, trnL-trnF, trnL intron, rbcL, matK, ITS1-ITS4, 18S rRNA) was performed to construct a database containing sequence information and DNA barcode universality. trnL-trnF barcode and ITS1-ITS4 barcode were the easiest markers for PCR amplification and sequence retrieval, and the combination of the two barcodes enabled single species identification in 18 out of 19 plants. Therefore, when an investigation of unknown poisonous plants is requested, combination of trnL-trnF and ITS1-ITS4 barcodes is considered as a primary marker for species identification. The database of recommended DNA barcodes for each poisonous plant presented in this study will be helpful in plants poisoning cases.

• International Journal of Industrial Entomology and Biomaterials
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• v.37 no.2
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• pp.82-89
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• 2018

This study was carried out to understand phylogenetic relationships of the 30 mulberry cultivars converved in Korea based on the ITS rDNA region, and they were compared to 40 reference sequences from GenBank. The size and the G+C content of the ITS rDNA gene regions from the 30 Korean mulberry cultivars and 40 reference sequences varied from 612-630 bp and 58.19-61.62%, respectively. Based on the results of the comparative phylogenetic analysis of the ITS rDNA regions of the 30 Korean mulberry cultivars and 40 reference sequences, they were divided into three groups (Group 1, 2, and 3) and two subgroups (Group 1A and 1B within Group 1). The sequence lengths of the Korean mulberry cultivar numbers 1-26 and 27-30 were 615 bp and 616 bp, respectively. At 205 bp location of ITS1 rDNA region, the cultivar numbers 1-26 contain the nucleotide thymine but the cultivar numbers 27-30 contain the nucleotide adenine. In addition, the insertion of the nucleotide adenine at 206 bp location was found only in the four Korean mulberry cultivars (numbers 27-30). Based on these sequence information and phylogenetic result, the 30 Korean mulberry cultivars were identified as M. alba and M. australis. This study will contribute to the construction of genetic database constructions and accurate variety identifications for unidentified mulberry varieties in Korea.

• Korean Journal of Plant Taxonomy
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• v.34 no.4
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• pp.335-358
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• 2004

To investigate molecular phylogenetic relationships and to test hypothesis of hybrid origin of Ranunculus cantoniensis (Ranunculaceae), the sequences of nrDNA and chloroplast DNA were analyzed for 8 taxa and 25 accessions including 5 accessions of outgroup. In the phylogenetic trees by analyses of maximum parsimony and maximum likelihood for ITS nrDNA sequences and combined data of psbA-trnH, rps16 and trnL sequences of cpDNA, R. cantoniensis was most closely related to R. chinensis, and then to R. taciroi and R. silerifolius. The molecular phylogenetic relationships were not congruent with the previous report that R. cantoniensis was most closely related to R. silerifolius. In the sequence analysis of ITS and psbA-trnH, rps16, trnL for R. cantoniensis and the related taxa, R. cantoniensis showed polymorphism. It supported that the polymorphism also was reported in chromosome number and karyotype of R. cantoniensis. Ranunculus cantoniensis shared the marker gene of R. chinensis and R. silerifolius in ITS, and one of R. silerifolius in cpDNA. These results supported the hypothesis that R. cantoniensis was caused by hybridization between R. chinensis and R. silerifolius based on chromosome number and karyotype, and also estimated that R. silerifolius might be of maternal origin and R. chinensis be paternal.

• Journal of Life Science
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• v.27 no.1
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• pp.89-94
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• 2017

DNA sequences of the intergenic spacer 1 and intergenic spacer 2 of the nineteen plants belonging Vitis genus were collected from the Genbank. DNA sequences of the same regions of Vitis thunbergii var. sinuata and Ampelopsis brevipedunculata var. heterophylla, both common plants in Korea, were not available in Genbank. Those two plants were collected, their genomic DNA encoding 18S rRNA, intergenic spacer 1, 5.8S rRNA, intergenic spacer 2 and part of 28S rRNA amplified and DNA sequence determined. DNA sequences of twenty-one plants including two Korean plants were aligned by the Multiple sequence comparison by log-expectation(MUSCLE) algorithm and the alignment was used to calculate neighbor-joining tree and pairwise distance. The results indicate DNA sequences of the two Korean plants are highly homologous with each other, but they are quite distantly related to the other Vitis plants. Distant relationship of the two Korean plants with the other Vitis plants might be due to independent evolution of those two plants in geographically isolated environment. Those two Korean plants are classified in different genera based on the morphology, one in Vitis genus and the other in Ampelopsis genus, providing another example of discrepancy between morphological and genetic classification.

• Journal of Sericultural and Entomological Science
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• v.41 no.3
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• pp.174-179
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• 1999

The genetic relationships among six Cordyceps spp. were investigated based on internal transcribed spacer sequences of ribosomal DNA .A portion of the these genes was amplified by PCR. Approximately 590 base pairs were successfully amplified, cloned, sequenced, compared. The nucleotide sequence of the six amplified fragments were aligned by the clustal W program. As a result, Cordyceps militaris shared 87, 96, 98, 90 and 97% sequences homology with Paecilomyces japonica, Paecilomyces sp. J300, Paeciomyces farinosa. Paecilomyces sp. J500 and Cordyceps sinensis, respectively. Paecilomyces japonica also shared 87, 88, 92 and 87% sequence similarity with Paecilomyces sp. J300, Paecilomyces farinosa, Paecilomyces sp. J500 and Cordyceps sinensis, repectively.