• Korean Journal of Microbiology
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• v.37 no.1
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• pp.49-55
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• 2001

Bacillus anthracis is a gram-positive spore-forming bacterium that causes the disease anthrax. The anthrax toxin contains three components, including the protective antigen (PA), which binds to eucaryotic cell surface receptors and mediates the transport of toxins into the cell. In this study, the entire 2,294-nucleotide protective antigen gene (pag) was sequenced from 4 of B. anthracis strains to identify potential variation in the toxin and to further our understanding of B. anthracis evolution in Korea. Sequence alignment of the entire PA gene from 30 strains representative of the four B. anthracis diversity groups revealed mutations. The mutation of B. anthracis BAK are located adjacent to a highly antigenic region crossing the junction between PA domains 3 and 4 shown to be critical to LF binding. The different mutational combinations observed in this study give rise to 11 PA genotypes and 4PA phenotypes. Three-dimensional analysis of all the amino acid changes (Ala to Val) observed in BAK indicated that these changes are not only close sequentially but also very close in three-dimensional space to the antigenic region importan tfor LF binding. Phylogenetic (cladistic) analysis of the pag corresponded with previous strain grouping based on chromosomal variation, suggesting that plasmid evolution in B. anthracis has occurred with little or no horizontal transfer between the different strains.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.75-79
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• 2001

An experiment was carried out to introduce OsHSP17.9, a low molecular HSP gene isolated from rice plant to orchardgrass (Dactylis glomerata L.) using Agrobacterium. Mature seed-derived calli of orchardgrass were co-cultured with Agrobacterium tumefaciens EHA101 harboring the plasmid pIG-HSP17.9 for transformation. Calli selected by hygromycin were transferred to N$_{6}$ medium containing 1 mg/L NAA, 5 mg/L kinetin, 250 mg/L cefotaxime and 50 mg/L hygromycin and several hygromycin resistant plants were obtained. Stable incorporation of the introduced OsHSP17.9 to the genome of the hygromycin resistant plants was confirmed by PCR and Southern blot analysis. Transformation efficiency was variable between cultivars in which it was 16.5% in Potomac and 8.0% in Frontier. Constitutive expression of the transgene in the transformed orchardgrass tissues was identified by Northern blot analysis but transcript levels were different among individual plants.s.

• Research in Plant Disease
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• v.29 no.4
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• pp.420-424
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• 2023

In 2020, within the Dongbaekdongsan area in Jeju Island, a Septobasidium sp. associated with a felt disease in Castanopsis sieboldii (Makino) Hatus. ex T. Yamaz. & Mashiba was identified. The symptom included the presence of brown, thin, and silk-like mycelial mats attached to the tree's bark, displaying variations in size from large to small. To induce hyphal growth, the samples collected were incubated in a moist chamber, and the newly formed hyphae were subjected to genomic DNA extractions. The nucleotide sequences of the internal transcribed spacer and small subunit rDNA genes were determined, and molecular characteristics among the isolates were investigated through polymerase chain reaction-based restriction fragment length polymorphism analysis. This Septobasidium sp. exhibited distinct morphological and phylogenetic features compared to those that were previously reported in South Korea. Consequently, this strain is taxonomically classified as a provisionally novel species of Septobasidium. Furthermore, the observed felt disease exhibited a high degree of host specificity, as it was exclusively identified in C. sieboldii without occurrence in other tree species at the time of observation.

• Korean Journal of Medicinal Crop Science
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• v.12 no.1
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• pp.60-66
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• 2004

This study was carried out to confirm the phylogenetic relationships in Korean Rhus species. Sequences from internal transcribed spacers (ITS) of nuclear ribosomal DNA and rbcL gene of chloroplast DNA were determined. Cotinus coggygria was selected as outgroup because it is closest allied with Rhus in Anacardiaceae. Also, ingroup was limited as six Korean Rhus species. ITS 1 sequences in six species of Rhus and one species of Cotinus ranged from 246 to 253 bp and ITS 2 sequences from 234 to 244 bp. Concerning the G+C content of the studied taxa, ITS 1 sequences ranged from 58.0 to 68.13% and ITS 2 from 59.75 to 68.46%. On the other hand, rbcL sequences were same size in the all species examined by 1,428 bp. G+C contents of rbcL sequences were ranged from 43.56 to 43.77% which means there are nearly no different from interspecies each other. Phylogenetic tree strongly supports the colse relationships between R. succedanea and R. sylvestris. Rhus javanica and Cotinus coggygria were also closely allied with each other in ITS and rbcL trees. Therefore, R. javanica was regarded as most primitive species among the Korean Rhus species. ITS 1 region of nuclear ribosomal DNA was suggested as very useful taxonomical marker for genus Rhus.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.1
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• pp.12-26
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• 2002

The phylogenetic relationships for 33 strains belonging to the genera Azorhizobium, Bradyrhizobium, Mesorhizobium, Rhizobium and Sinorhizobium were conducted by the sequence analyses of the ITS regions. The sequence homologies of these strains showed the high variations(28.0 - 94.9%). According to the phylogenetic analysis of ITS regions. 37 ITS clones from 33 strains of 32 species were classified into four groups. Group I included all strains of the genus Sinorhizobium as core members and R. giardinii as a peripheral member. The genus Rhizobium strains were clustered into group II which was very heterogeneous and the tree toplogy of this group were very unstable. Among the members of group II. the taxonomic position of R. radiobacter and R. rubi was not clearly identified on the basis of ITS I regions. R. undicola and R. vitis were remotely related with other Rhizobium strains including R. leguminosarum, R. galegae, R. gallicum, R. mongolense, R. tropici, R. hainanense, R. rhizogense and R. huautlense of group II were supposed to be loosely related to R. leguminosarum. While the stains of the genera Bradyrhizobium constituted group III with Azorhizobium caulindans, the strains of the genus Mesorhizobium formed group IV on the relatively high sequence homology level.

• Korean Journal of Plant Taxonomy
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• v.39 no.3
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• pp.135-142
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• 2009

Phylogeny of the family Ophioglossaceae and a phylogenetic position of Mankyua were estimated through analyses of chloroplast rbcL gene sequences and spore morphology. Sequence analysis of the rbcL gene clearly indicated that there are two major lineages in the family Ophioglossaceae: Botrychioid lineage and Ophioglossoid lineage. The Botrichioid lineage is composed of three distinct clades: Botrychium, Helminthostachys and Mankyua, where Helminthostachys and Mankyua were placed as sister groups to the Botrychium. Within the genus Botrychium, subgenera Septridium and Botrychium were monophyletic, while taxa of subgen. Botrypus branched as sister of the two, successively, thus making a non-monophyletic group. Ophioglossum formed the Ophioglossoied lineage, where the subgen. Ophioglossum is monophyletic, while subgen. Cheiroglossa and Ophoderma formed a sister relationship with subgen. Ophioglossum. In terms of external morphology and spores, Mankyua is most similar to Helminthostachys, however, patristic distance in the cladogram and trophophore characteristics of the two genera are distinct. Therefore, Mankyua is a well defined genus within the family in terms of morphology as well as molecular phylogeny which places it in basal position of the Botrychioid lineage on the gene tree.

• Korean Journal of Poultry Science
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• v.41 no.1
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• pp.7-14
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• 2014

Tyrosinase (TYR) gene is located on chromosome 1 in chicken and it is composed of five exons and four introns. TYR gene is described as a key enzyme in melanin biosynthesis. Most examples of complete albinism in chicken have been due to defects in the tyrosinase gene. The association of feather color and sequence polymorphism in the Tyrosinase (TYR) gene was investigated using Korean Native chicken H breed (H_PL), Korean Native chicken L/W breed(L/W_PL) and 'Woorimatdag' commercial chickens (Woorimatdag_CC). From L_PL and W_PL breed analyses, 4 synonymous SNPs (locus G33A, G116A, C217T and C247T) and 2 SNPs (G838A and G958A) were detected in 4th exon and 4th intron of TYR gene respectively. The genotype frequencies for 6 SNPs were compared between L_PL and W_PL and W_PL represented homozygous SNP types in all the analyzed SNP positions while L_PL displayed various SNP types.

• Biomedical Science Letters
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• v.6 no.2
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• pp.131-139
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• 2000

RAPD-PCR was applied to identify the phylogenetic relationship between isolated Korean-type coliphages ($\phi$C1, $\phi$C2, $\phi$C3 and $\phi$C4) and well-known American coliphages ($\phi$T2, $\phi$T4, $\phi$T5, $\phi$T7 and ${\phi}{\lambda}$). Subsequently, a computer analysis was carried out with the results of RAPD-PCR. As a result, 9 individuals were divided into five groups. The Korean-type coliphages formed a single cluster which showed very high genetic similarity but the American-type coliphages revealed very low genetic similarity among them. In particular, the $\phi$T2와 $\phi$T4 (T$_{even}$ phages) made one sub-cluster among American coliphages, and they were very distant from $\phi$T5, $\phi$T7 and ${\phi}{\lambda}$. However, ${\phi}{\lambda}$ made a cluster with the Korean-type coliphages that we isolated. The genome size of Korean-type coliphages was ranged from 25,000 bp to 35,000 bp. Among them, the genome of $\phi$C2 was the smallest and that of $\phi$C1 was the biggest, while others were in the middle of the size.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.61-67
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• 2017

Two major sex pheromone components (Z-8-dodecenyl acetate and E-8-dodecenyl acetate) are known in the peach fruit moth, Grapholita molesta. From a putative biosynthetic pathway of these sex pheromone components, delta 10 desaturase ($10{\Delta}$ DES) has been proposed to play a crucial role in synthesizing a species-specific stereoisomer of the double bond. However, its molecular identity was not known. This study determined a putative desaturase (Gm-comp1575) as a $10{\Delta}$ DES candidate from G. molesta transcriptome constructed from the sex pheromone gland. Its open reading frame encodes 370 amino acid sequence with a predicted molecular weight at 43.2 kDa and isoelectric point at 8.77. It was predicted to have four transmembrane domains and six glycosylation sites at N-terminal or cytosolic domains. A phylogenetic analysis with its predicted amino acid sequence indicated that Gm-comp1575 is closely related with known $10{\Delta}$ DES genes of other insects. Gm-comp1575 transcript was detected in female adults at sex pheromone gland and other abdominal tissues. RNA interference of Gm-comp1575 significantly reduced attractiveness of virgin females in apple orchard compared to control females. These results suggest that Gm-comp1575 is associated with sex pheromone biosynthesis of G. molesta.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.35-42
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• 2011

The study was conducted to select and optimize microsatellite (MS) markers for evaluation of Korean native pig (KNP) populations in order to provide standard for the classification and breed definition of the indigenous breeds. The study also aimed to characterize and classify each KNP populations. A total of 648 pigs from 17 pig populations including six KNP, four Chinese native pig and four commercial pig populations were analyzed with 26 MS markers. KNP populations formed separate cluster from those of Chinese native pig and introduced pig populations. Expected heterozygosity (He) of KNP populations were 0.48~0.55 except two populations with 0.65. Genetic distances between KNP populations were relatively shorter: 0.12-0.34. Among six KNP populations, three showed high genetic uniformity, two showed lower uniformity and one showed high level of impurity and heterozygosity. The results can be used to evaluate and manage animal genetic resources at national scale.