• 생명과학회지
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• 제21권6호
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• pp.788-795
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• 2011

병원균에 대한 정확한 동정은 임상 연구실에서 필수적인 요소의 하나이다. Chyseobacterium indologenes에 대한 동정을 포함한 분자생물학적 분석과 리보솜의 16S rRNA 유전자로 한국에서 추출한 17검체와 GenBank에서 Chyseobacterium속 검색을 통해 이들과 계통관계를 평가하였다. C. indologenes의 배당 서열은 1,176 nucleotides였다. C. indologenes 내의 서열 변이는 주로 염기 치환이었다. 한국의 C. indologenes 검체는 다른 나라의 동 종과 크게 다르지 않았다. 그런데 한국의 C. indologenes의 치환율은 GenBank에 있는 동종보다 높았다. C. indologenes는 C. isbiliense, C. hominis, C. hispanicum, C. molle, C. hungaricum, and C. pallidum과 자매종을 형성하였다.

• 한국균학회지
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• 제47권1호
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• pp.89-94
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• 2019

중국에서 범부채의 녹병균이 Puccinia iridis로 동정됨에 따라 우리나라에서도 범부채의 녹병균을 재검토하였다. 저자들이 채집한 2점의 시료를 형태적으로 검토한 결과 모두 P. iridis의 특징과 일치하였다. 또한 유전분석한 결과 ITS 및 LSU rDNA 영역의 염기서열이 기존에 기록된 P. iridis와 각각 100% 및 99%의 상동성을 나타냈다. 이를 Neighbor-joining 분석법으로 계통수를 작성하였을 때도 P. iridis 계통군에 속하였다. 따라서 우리나라에서 범부채의 녹병균으로 P. iridis의 존재가 확인되었다. 한편, 우리나라에서 2003년에 범부채의 녹병균으로 기록된 Puccinia belamcandae에 대한 재검토는 향후 숙제로 남게 되었다.

• The Plant Pathology Journal
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• 제40권2호
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• pp.171-191
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• 2024

Identification of Helicotylenchus species is very challenging due to phenotypic plasticity and existence of cryptic species complexes. Recently, the use of rDNA barcodes has proven to be useful for identification of Helicotylenchus. Molecular markers are a quick diagnostic tool and are crucial for discriminating related species and resolving cryptic species complexes within this speciose genus. However, DNA barcoding is not an error-free approach. The public databases appear to be marred by incorrect sequences, arising from sequencing errors, mislabeling, and misidentifications. Herein, we provide a comprehensive analysis of the newly obtained, and published DNA sequences of Helicotylenchus, revealing the potential faults in the available DNA barcodes. A total of 97 sequences (25 nearly full-length 18S-rRNA, 12 partial 28S-rRNA, 16 partial internal transcribed spacer [ITS]-rRNA, and 44 partial cytochrome c oxidase subunit I [COI] gene sequences) were newly obtained in the present study. Phylogenetic relationships between species are given as inferred from the analyses of 103 sequences of 18S-rRNA, 469 sequences of 28S-rRNA, 183 sequences of ITS-rRNA, and 63 sequences of COI. Remarks on suggested corrections of published accessions in GenBank database are given. Additionally, COI gene sequences of H. dihystera, H. asiaticus and the contentious H. microlobus are provided herein for the first time. Similar to rDNA gene analyses, the COI sequences support the genetic distinctness and validity of H. microlobus. DNA barcodes from type material are needed for resolving the taxonomic status of the unresolved taxonomic groups within the genus.

• 대한미생물학회지
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• 제34권6호
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• pp.561-571
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• 1999

Diagnosis of mycobacterial infection is dependent upon the isolation and identification of causative agents. The procedures involved are time consuming and technically demanding. To improve the laborious identification process mycobacterial systematics supported by gene analysis is feasible, being particularly useful for slowly growing or uncultivable mycobacteria. To complement genetic analysis for the differentiation and identification of mycobacterial species, an alternative marker gene, rpoB encoding the ${\beta}$ subunit of RNA polymerase, was investigated. rpoB DNAs (342 bp) were amplified from 52 reference strains of mycobacteria including Mycobacterium tuberculosis H37Rv (ATCC 27294) and clinical isolates by the PCR. The nucleotide sequences were directly determined (306 bp) and aligned using the multiple alignment algorithm in the MegAlign package (DNASTAR) and MEGA program. A phylogenetic tree was constructed with a neighborhood joining method. Comparative sequence analysis of rpoB DNA provided the basis for species differentiation. By being grouped into species-specific clusters with low sequence divergence among strains belonging to same species, all the clinical isolates could be easily identified. Furthermore RFLP analysis enabled rapid identification of clinical isolates.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1301-1307
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• 2014

White-rot fungi of the genus Bjerkandera are cosmopolitan and have shown potential for industrial application and bioremediation. When distinguishing morphological characters are no longer present (e.g., cultures or dried specimen fragments), characterizing true sequences of Bjerkandera is crucial for accurate identification and application of the species. To build a framework for molecular identification of Bjerkandera, we carefully identified specimens of B. adusta and B. fumosa from Korea based on morphological characters, followed by sequencing the internal transcribed spacer region and 28S nuclear ribosomal large subunit. The phylogenetic analysis of Korean Bjerkandera specimens showed clear genetic differentiation between the two species. Using this phylogeny as a framework, we examined the identification accuracy of sequences available in GenBank. Analyses revealed that many Bjerkandera sequences in the database are either misidentified or unidentified. This study provides robust reference sequences for sequence-based identification of Bjerkandera, and further demonstrates the presence and dangers of incorrect sequences in GenBank.

• 환경생물
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• 제41권2호
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• pp.145-166
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• 2023

Parrots have been threatened by global trade to meet their high demand as pets. Controlling parrot trade is essential because parrots play a vital role in the ecosystem. Accurate species identification is crucial for controlling parrot trade. Parrots have been traded as eggs due to their advantages of lower mortality rates and more accessible transport than live parrots. A molecular method is required to identify parrot eggs because it is difficult to perform identification using morphological features. In this study, DNAs were obtained from 43 unidentified parrot eggs using a non-destructive sampling method. Partial cytochrome b (CYTB) gene was then successfully amplified using polymerase chain reaction (PCR) and sequenced. Sequences newly obtained in the present study were compared to those available in the GenBank by database searching. In addition, phylogenetic analysis was conducted to identify species using available sequences in GenBank along with sequences reported in previous studies. Finally, the 43 parrot eggs were successfully identified as seven species belonging to two families and seven genera. This non-destructive sampling method for obtaining DNA and molecular identification might help control the trade of parrot eggs and prevent their illegal trade.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.124-129
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• 2005

The Growing Self-Organizing Map (GSOM), an extended type of the Self-Organizing Map, is a widely accepted tool for clustering high dimensional data. It is also suitable for the clustering of short DNA sequences of phylogenetic genomes by their oligonucleotide frequency. The GSOM presents the result of the clustering process visually on a coloured map, where the clusters can be identified by the user. This paper describes a proposal for automatic cluster detection on this map without any participation by the user. It has been applied with good success on 20 different data sets for the purpose of species separation.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.79-86
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• 2005

Molecular markers have increasingly been used in plant genetic analysis, due to their obvious advantages over conventional phenotypic markers, as they are highly polymorphic, more in number, stable across different developmental stages, neutral to selection and least influenced by environmental factors. Among the PCR based marker techniques, ISSR is one of the simplest and widely used techniques, which involves amplification of DNA segment present at an amplifiable distance in between two identical microsatellite repeat regions oriented in opposite direction. Though ISSR markers are dominant like RAPD, they are more stable and reproducible. Because of these properties ISSR markers have recently been found using extensively for finger printing, pohylogenetic analysis, population structure analysis, varietal/line identification, genetic mapping, marker-assisted selection, etc. In mulberry (Morus spp.), ISSR markers were used for analyzing phylogenetic relationship among cultivated varieties, between tropical and temperate mulberry, for solving the vexed problem of identifying taxonomic positions of genotypes, for identifying markers associated with leaf yield attributing characters. As ISSR markers are one of the cheapest and easiest marker systems with high efficiency in generating polymorphism among closely related varieties, they would play a major role in mulberry genome analysis in the future.

• ALGAE
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• 제21권4호
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• pp.349-375
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• 2006

The application of modern ecological, ultrastructural and molecular methods, aided by the cultivation of numerous cyanobacterial morphotypes, has substantially changed our knowledge of these organisms. It has led to major advances in cyanobacterial taxonomy and criteria for their phylogenetic classification. Molecular data provide basic criteria for cyanobacterial taxonomy; however, a correct phylogenetic system cannot be constructed without combining genetic data with knowledge from the previous 150 years research of cyanobacterial diversity. Thus, studies of morphological variation in nature, and modern morphological, ultrastructural, ecophysiological and biochemical characters need to be combined in a “polyphasic” approach. Taxonomic concepts for generic and infrageneric ranks are re-evaluated in light of combined phenotypic and molecular criteria. Despite their usefulness in experimental studies, the limitations of using strains from culture collections for systematic and nomenclatural purposes is highlighted. The need for a continual revision of strain identification and proper nomenclatural practice associated with either the bacteriological or botanical codes is emphasized. Recent advances in taxonomy are highlighted in the context of prospects for understanding cyanobacterial diversity from natural habitats, and the evolutionary and adaptational processes that cyanobacteria undergo.

• Fisheries and Aquatic Sciences
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• 제13권4호
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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.