• ALGAE
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• v.29 no.2
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• pp.75-99
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• 2014

A small dinoflagellate, Ansanella granifera gen. et sp. nov., was isolated from estuarine and marine waters, and examined by light microscopy, scanning electron microscopy, and transmission electron microscopy. In addition, the identity of the sequences (3,663-bp product) of the small subunit (SSU), internal transcribed spacer (ITS) region (ITS1, 5.8S, ITS2), and D1-D3 large subunit (LSU) rDNA were determined. This newly isolated, thin-walled dinoflagellate has a type E eyespot and a single elongated apical vesicle, and it is closely related to species belonging to the family Suessiaceae. A. granifera has 10-14 horizontal rows of amphiesmal vesicles, comparable to Biecheleria spp. and Biecheleriopsis adriatica, but greater in number than in other species of the family Suessiaceae. Unlike Biecheleria spp. and B. adriatica, A. granifera has grana-like thylakoids. Further, A. granifera lacks a nuclear fibrous connective, which is present in B. adriatica. B. adriatica and A. granifera also show a morphological difference in the shape of the margin of the cingulum. In A. granifera, the cingular margin formed a zigzag line, and in B. adriatica a straight line, especially on the dorsal side of the cell. The episome is conical with a round apex, whereas the hyposome is trapezoidal. Cells growing photosynthetically are $10.0-15.0{\mu}m$ long and $8.5-12.4{\mu}m$ wide. The cingulum is descending, the two ends displaced about its own width. Cells of A. granifera contain 5-8 peripheral chloroplasts, stalked pyrenoids, and a pusule system, but lack nuclear envelope chambers, a nuclear fibrous connective, lamellar body, rhizocysts, and a peduncle. The main accessory pigment is peridinin. The SSU, ITS regions, and D1-D3 LSU rDNA sequences differ by 1.2-7.4%, >8.8%, and >2.5%, respectively, from those of the other known genera in the order Suessiales. Moreover, the SSU rDNA sequence differed by 1-2% from that of the three most closely related species, Polarella glacialis, Pelagodinium bei, and Protodinium simplex. In addition, the ITS1-5.8S-ITS2 rDNA sequence differed by 16-19% from that of the three most closely related species, Gymnodinium corii, Pr. simplex, and Pel. bei, and the LSU rDNA sequence differed by 3-4% from that of the three most closely related species, Protodinium sp. CCMP419, B. adriatica, and Gymnodinium sp. CCMP425. A. granifera had a 51-base pair fragment in domain D2 of the large subunit of ribosomal DNA, which is absent in the genus Biecheleria. In the phylogenetic tree based on the SSU and LSU sequences, A. granifera is located in the large clade of the family Suessiaceae, but it forms an independent clade.

• Korean Journal of Plant Taxonomy
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• v.41 no.4
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• pp.324-328
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• 2011

The purpose of this study was to analyze the interspecific relationships of Chenopodium album and its related taxa collected in Korea. The 18S-26S ribosomal DNA (45S rDNA) loci were detected directly on mitotic chromosomes by fluorescence in situ hybridization (FISH) and the chromosome numbers were examined using aceto-orcein methods. The chromosomal numbers of Chenopodium album var. album and C. album var. centrorubrum were 2n = 6x = 54, whereas for C. album var. stenophyllum, this number was 2n = 4x = 36. The basic chromosome number was x = 9. The biotin labeled 18S-26S rDNA probe exhibited eight yellow fluorescent signals on the metaphase chromosome of C. album var. album and var. centrorubrum respectively, while two yellow signals of C. album var. stenophyllum were noted. All of the signals on the chromosomes were located at the terminal regions. The chromosome number and FISH findings suggest that C. album var. centrorubrum is merged into var. album and that it is clearly distinguished from C. album var. stenophyllum.

• Journal of Korean Society of Forest Science
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• v.108 no.2
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• pp.200-207
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• 2019

The aim of this study was to provide the basic information necessary to identify Korean fir (Abies holophylla), momi fir (A. firma), and Nikko fir (A. homolepis), and other fir trees planted in South Korea that are protected by law. Analysis of the morphological characteristics of the needles from each sample was investigated. The shape of the needle-leaf tip from A. holophylla was acute, whereas that from A. firma and A. homolepis was emarginate and that from the protected fir trees was obtuse. The number of stomata on the needles was not significantly different between A. holophylla and A. firma, and the number of stomata on the needles from A. homolepis and the protected fir trees were highly similar. In addition, the genetic differences among the Abies species were analyzed using the sequences of five chloroplast DNA regions-matK, atpF-atpH, rpoC2-rps2, rpoC1, and psbA-trnH.The atpF-atpH and psbA-trnH regions were useful for discriminating A. firma from the other species, but there were no differences among A. holophylla, A. homolepis, and the protected fir trees. The same chloroplast sequences were found in both A. holophylla and A. homolepis, which suggests that additional genetic studies might be necessary to identify the Abies species planted in both South Korea and Japan.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.4
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• pp.238-244
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• 2007

Nowadays many people are concerned about being healthy, and many dairy products are taken as health supplementary foods. Among dairy products, kefir, also called as Tibet mushroom, is a yogurt fermented by kefir grain, which is a mixture of lactic acid bacteria and yeasts. Although there are many empirical evidences that kefir is very influential for human body, the exact reason is not definitively discovered. Therefore, it would be useful to understand characteristics of a kefir grain and to categorize bacteria in a kefir grain. In this paper, molecular biological apparatus such as PCR, electrophoresis, PCR purification, DNA sequencing were used to identify and classify the species of lactic acid bacteria and yeast in a kefir grain. We used PCR-based identification method using 16S rRNA primer and Internal Transcribed Spacer (ITS) primer. We identified 6 different species which were selected on different medium. In addition, observation with scanning electron microscope (SEM) enabled us to grasp an external shape of the kefir grain. Although we found a limited number of microbial species, more intensive research are needed for extensive identification of microorganism species in Korean kefir grain.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.967-972
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• 2022

We investigated the molecular and morphological traits of 338 individual macrourids collected from the Southern Ocean (FAO area number, 88.1 and 88.3) between 2021 and 2022 by Korean bottom trawls. We first identified them as Macrourus caml and Macrourus whitsoni based on morphological traits, such as the number of pelvic fin rays (PF) and the rows of lower jaw teeth (LJT). However four individuals showed uncategorizable morphological characteristics such as PF and LJT numbers that overlapped between the two species. Subsequently, we obtained and analyzed 509 bp of the mtDNA COI sequences of 49 individuals, including the four unidentified individuals, and found only one single nucleotide polymorphism (SNP) that distinguished the two species. Finally, using our molecular identification key, we confirmed that each two individuals were misidentified as M. whitsoni and M. caml reversely. Our results suggest that the number of PF and LJT should be investigated together to accurately identify the two species.

• ALGAE
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• v.35 no.4
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• pp.325-335
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• 2020

A new diatom species, Mayamaea vietnamica sp. nov., is described from Cát Tiên National Park in Vietnam. This species was discovered and described from soil samples. Algae from soil ecosystems in Vietnam are almost unknown. The new species is described on the basis of an integrated approach with molecular and morphological data, and comparison with similar species. In terms of molecular data, 18S rDNA (including V4 domain), and partial rbcL plastid genes show M. vietnamica sp. nov. is most closely related to M. terrestris N. Abarca and R. Jahn, and together they form a monophyletic group relative to other members of the genus. M. vietnamica sp. nov. differs from other species in the genus by the number of striae and areolae in 10 ㎛, number of areolae per stria, as well as shape and presence or absence of axial and central areas.

• Korean Journal of Medicinal Crop Science
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• v.17 no.1
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• pp.26-32
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• 2009

The region containing 18S rRNA gene, ITS 1 and part of the 5.8S rRNA gene of the Atractylodes japonica Koidz was amplified by PCR and the product cloned in a pBluescript SK II plasmid. DNA sequence of the cloned DNA was determined and submitted to the GenBank (accession number EU678363). Phylogenetic analysis of the ITS 1 DNA showed close similarity with the other plant species of the family Compositae. The extract of the plant materials of five different members of the family Compositae was analyzed by HPLC to detect atractylon. Extract of the A. japonica Koidz showed presence of significant amount of atractylon. However, noticeable amount of atractylon was not detected by the same analyses from the extracts of the other plants belonging to the family Compositae including Artemisia capillaris, Chrysantemum zawadskii, Eclipta prostrata or Taraxacum platycarpum.

• KSBB Journal
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• v.17 no.1
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• pp.1-13
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• 2002

Label-free optical methods for the monitoring of interactions between biological molecules have become increasingly popular within the last decade. A rising number of publications have demonstrated the benefits of direct biomolecular interaction analysis(BIA) for biology and biochemistry, such as antigen-antibody Interactions, receptor-ligand interactions, protein-DNA, DNA- intercalator, and DNA-DNA interactions. This article gives an overview of the historical development, principle and application of label-free optical biosensor to examine the functional characteristics of biospecific interaction, such as kinetics, affinity, and binding position of biomolecular between an immobilized species at the transducer surface and its dissolved binding partner.

• Journal of Aquaculture
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• v.20 no.4
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• pp.248-254
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• 2007

Representative cDNA libraries were constructed from various tissue sources of Hemibarbus mylodon, an endangered freshwater fish species in Korea, for the mining of expressed sequence tags (ESTs). Randomized and non-normalized EST analysis was performed with 7 unidirectional cDNA libraries generated from brain, intestine, kidney, liver, muscle, ovary or testis. Of 3,383 ESTs in total, the number of singleton was 2,029, and 333 contigs containing 1,354 ESTs were assembled (percent of unigene = 70.0%). Abundantly expressed gene transcripts and broad clustering of putative gene function were tissue-specific in general, and the redundancy was also variable among those libraries. Over half of H. mylodon ESTs were matched with orthologues from other teleosts among which zebrafish gene sequences were the most frequent in those matches. This initial setting of EST libraries achieved in the present study would be a fundamental basis for the banking of gene resources from this endangered fish species.

• Korean Journal of Plant Resources
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• v.17 no.3
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• pp.265-271
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• 2004

Genetic variation is the basis of crop improvement. Limited genetic diversity in a crop species may restrict the amount of genetic improvement that can be achieved through plant breeding. Soybean is one of the world's most important crops. A potential source of genetic variability for the cultivated soybean is the wild species G. soja Sieb. ＆amp; Zucc. Amplified fragment length polymorphism (AFLP) analysis is a PCR-based technique, which can detect a 10-fold greater nubmer of loci than other DNA marker analysis. Twenty cultivated soybeans and two-hundred wild soybeans were used to determine genetic vatiations by AFLPs and evaluate the usefulness of AFLPs as DNA markers. Six-hundred and ten fragments were detected with an average of 56 AFLP fragments produced per primer in a total of 11 AFLP primer pairs. The number of polymorphic loci detected per primer ranged from 7 to 20 and the polymorphism was greater in wild than in cultivated soybean. F$_2$ segregation analysis of four AFLP fragments in combination of Hwaeomputkong ${\times}$ PI 417479 indicated that they segregate as stable Mendelian loci with 3 : 1. This results strongly suggest that the AFLP analysis is a good technique for the detection of genetic polymorphism in a wide plant species.