• Journal of Microbiology
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• 제40권2호
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• pp.109-118
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• 2002

The present work is aimed at providing additional new pure cultures of oxalate utilizing bacteria and its preliminary characterization for further work in the field of oxalate-metabolism and taxonomic studies. The taxonomy of 14 mesophilic, aerobic oxalotrophic bacteria isolated by an enrichment culture technique from soils rhizosphers, and the juice of the petiole/stem tissue of plants was investigated. Isolates were characterized with 95 morphological, biochemical and physiological tests. Cellular lipid components and carotenoids of isolates were also studied as an aid to taxonomic characterization. All isolates were Gram-negative, oxidase and catalase positive and no growth factors were required. In addition to oxalates, some of the strains grow on methanol and/or formate. The taxonomic similarities among isolates, reference strains or previously reported oxalotrophic bacteria were analysed by using the Simple Matching (S/ sub SM/) and Jaccard (S$\_$J/) Coefficients. Clustering was performed by using the unweighted pair group method with arithmetic averages (UPGMA) algorithm. The oxalotrophic strains formed five major and two single-member clusters at the 70-86% similarity level. Based on the numerical taxonomy, isolates were separated into three phenotypic groups. Pink-pigmented strains belonged to Methylobacterium extorquens, yellow-pigmented strains were most similar to Pseudomonas sp. YOx and Xanthobacter autorophicus, and heterogeneous non-pigmented strains were closely related to genera Azospirillum, Ancylobacter, Burkholderia and Pseudomonas. New strains belonged to the genera Pseudomonas, Azospirillum and Ancylobacter that differ taxonomically from other known oxalate oxidizers were obtained. Numerical analysis indicated that some strains of the yellow-pigmented and nonpigmented clusters might represent new species.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.184-190
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• 1999

To acquire an industrially useful biocatalyst for the enzymatic synthesis and production of various D-amino acid aminotransferase (D-AAT) activity. The enzyme activity was found from 110 strains of isolated thermophiles revealing its wide occurrence in thermophiles. Enzyme activity and thermal stability of the D-AAT producers were compared. Finally we have selected four thermophiles as producers of potent biocatalysts for the D-amino acid production; two thermophiles, Bacillus sp. Lk-1 and LK-2, having higher specific activity and two thermophiles, B. stearothermophilus KL-01 and Bacillus sp. KLS-01, having higher thermal stability than the D-AAT producers. Taxonomic and physiological characteristics of the four isolated thermophiles were described herein.

• 한국잠사곤충학회지
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• 제31권2호
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• pp.113-120
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• 1989

가잠에서 분리된 새로운 미포자충(S85)의 특성을 구명하기 위한 일환으로 포자의 미세구조를 전자현미경으로 관찰한 결과는 아래와 같다. 1. 포자는 전자밀도가 상이한 3층의 피각으로 되어 있으며 그 외각은 전자밀도가 높고 요철이 다소 심한 편이고 내각은 전자밀도가 낮으며 포자피각 두께의 대부분을 차지하였다. 2. 극막층은 그 배열이 조밀하고 성긴 두 부분의 Lamellae 구조로 되어 있었다. 3. 극사는 13개의 coil을 가지고 있으며 전자밀도가 서로 다른 8개의 동심원층으로 되어 있었다. 4. 포자는 1개의 핵을 가지고 있으며 다포자아막을 형성하고 막내에 16개 이상의 포자를 가지고 있었다. 5. 포자의 표면은 거칠고 주름이 있으며 다포자 아막은 고무풍선처럼 생긴 얇은 막구조로서 표면에는 약간의 주름이 있었다.

• 식물분류학회지
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• 제47권1호
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• pp.6-10
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• 2017

Microsatellite markers were isolated for Daphne kiusiana var. kiusiana (Thymelaeaceae), an evergreen broad-leaved shrub endemic to Korea and Japan. Because its populations in Jeju Island are morphologically controversial, and consistently threatened by anthropogenic pressures, taxonomic delimitation and conservation effort are required at the genetic level. We developed 21 polymorphic microsatellite loci from Next Generation Sequencing data. The primer set included di-, tri-, and tetra-nucleotide repeats. Variability in the markers was tested for 80 individuals of D. kiusiana from three natural populations in Jeju Island and Japan. Among the 21 loci, three were unavailable for population JKJU of Japan. The Neighbor-Joining tree based on microsatellite markers described here classified the three populations into two groups according to geographical or morphological traits. These will be a powerful genetics tool for determining the taxonomic boundary and establishing suitable conservation strategies for D. kiusiana in Jeju Island.

• 생태와환경
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• 제54권2호
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• pp.125-129
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• 2021

Chironomids are a large group of invertebrates that live in various aquatic habitats. The distribution range of these invertebrates has become varied due to anthropogenic impacts; as such, their distribution can be used as an indicator of environmental health. Adult chironomids are well known in South Korea; however, the larvae have rarely been studied due to difficulties associated with morphological classification. To address this lack of information, we collected larvae from four important rivers in South Korea and summarized their taxonomic morphological characteristics. The antennae, mandible, and mentum were used for larval taxonomic characterization. In this study, we describe the basic morphological features and key pictorial features of 20 species of chironomids, representing 16 genera.

• Journal of Plant Biotechnology
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• 제49권2호
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• pp.139-144
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• 2022

The genus Prunus (family: Rosaceae) consists of over 400 plant species and exhibits vast biodiversity worldwide. Given the wide distribution of this genus, its taxonomic classification is important. Anatomical characteristics are conserved and stable and can therefore be used as an important tool for the taxonomic characterization of plants. Therefore, this study aimed to assess and document the anatomical characteristics of the leaf, stem, and seed of P. africana using micrographs and photographs for possible use in the identification, quality control, and phylogenetic analysis of the species. The anatomical sections of a young stem revealed a cortex consisting of isodiametric parenchyma cells, druse crystals, primary vascular bundles, and pith. The mature stem bark majorly consisted of the rhytidome, with the periderm densely arranged in multiple layers; a cluster of stone cells; and sclerenchyma. The leaf sections were hypostomatic, with stomata sizes ranging from 18.90-(22.34)-26.90 × 15.41-(18.40)-21.22 ㎛. The leaf sections showed the presence of characteristic druse crystals, vascular bundles, and mesophyll layers. The pericarp contained the epicarp, mesocarp, and endocarp, with their thickness being approximately 350-400, 300-350, and 30-50 ㎛, respectively. In addition, it contained a seed testa with a thickness of approximately 50-60 ㎛. The morphological and anatomical characteristics observed in P. africana leaves, stems, and seeds in this study could serve as useful data for the taxonomic identification of this species.

• 한국어병학회지
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• 제16권1호
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• pp.51-59
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• 2003

Streptococcal infection is one of the most serious disease of cultured olive flounder, Paralychthys olivaceus in Korea and caused by more than one species. However, there has been considerable confusions about the taxonomic position of the fish pathogenic streptococci. In this study, We performed the randomly amplified polymorphic DNA(RAPD) pattern analysis to evaluate the possible classification in 8 streptococci isolated from diseased olive flounder and reference strains based on their DNA structure. RAPD PCR with DNA solution prepared by simple boiling and 10-mer random primer was appeared to be a good tool for discrimination of different streptococcal strains. Phenotypical characters by simple biological test and API 20 Strep corresponded well to the specific profiles of RAPD in streptococcal isolates of this study. Therefore, the RAPD profile was considered as one of differential characters to discriminate the streptococcal isolates from diseased olive flounder.

• Journal of Microbiology and Biotechnology
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• 제3권1호
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• pp.57-60
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• 1993

The herbicidal compound, 3D5 was isolated from the culture broth of strain 3D5, a soil isolate. Based on taxonomic studies, this culture was identified as Streptomyces sp. 3D5.

• BMB Reports
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• 제41권3호
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• pp.217-222
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• 2008

Based on a five-letter model of the 20 amino acids, we propose a new 2-D graphical representation of protein sequence. Then we transform the 2-D graphical representation into a numerical characterization that will facilitate quantitative comparisons of protein sequences. As an application, we construct the phylogenetic tree of 56 coronavirus spike proteins. The resulting tree agrees well with the established taxonomic groups.

• 천문학회보
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• 제43권1호
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• pp.42.1-42.1
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• 2018

Deep Ecliptic Patrol of the Southern Sky (DEEP-South) observation is being made during the off-season for exoplanet survey, using Korea Microlensing Telescope Network (KMTNet). An optimal combination of its prime focus optics and the 0.3 billion pixel CCD provides a four square degrees field of view with 0.4 arcsec/pixel plate scale which is also best suited for small body studies. Normal operation of KMTNet started in October 2015, and a significant portion of the allocated telescope time for DEEP-South is dedicated to targeted observation, Opposition Census (OC), of near-Earth asteroids for physical and taxonomic characterization. This is effectively achieved through multiband, time series photometry using Johnson-Cousins BVRI filters. Uninterrupted monitoring of the southern sky with KMTNet is optimized for spin characterization of a broad spectrum of asteroids ranging from the near-Earth space to the main-belt, including binaries, asteroids with satellites, slow/fast- and non-principal axis-rotators, and thus is expected to facilitate the debiasing of previously reported lightcurve observations. Our software subsystem consists of an automated observation scheduler, a pipelined data processing system for differential photometry, and an easy-to-use lightcurve analysis toolkit. Lightcurves, spin periods and provisional determination of class of asteroids to which the lightcurve belongs will be presented, using the dataset from first year operation of KMTNet. Our new taxonomic classification scheme for asteroids will also be summarized.