• 생명과학회지
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• 제13권6호
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• pp.856-864
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• 2003

원핵생물 (Procaryote)의 분류에 16S rRNA유전자가 많이 이용되어 있으나 제한된 해상력과 유전자의 수에 차이가 있는 등의 문제가 있어 이를 보완할 수 있는 새로운 생체분자를 찾고 그 분류 결과를 16S rRNA의 결과와 비교하였다. COG (Clusters of Orthologous of protein) 방법을 이용하여 43종의 미생물중에서 진핵생물을 제외한 42종의 원핵생물 (procaryote)에서만 발견되는 3종류의 COG인 Transcription elongation factor인 COG0195과 bacterial DNA primase인 COG0358 그리고 uridylate kinase인 COG0528를 구하였다. 이중 유사도와 유전자 수를 바탕으로 새로운 분류의 키로 uridylate kinase를 설정하여 분석한 결과, 같은 속 (genus)에 속하는 세균들은 아주 높은bootstrap value를 갖고 분류도에서 같은 위치에 분포하고 고세균 (Archaebacteria) 내부의 응집성이 높은 등의 유사성을 보였다. 한편 alpha와 epsilon 그룹의 Proteobacteria가 분류도에서 다르게 위치하고 진정세균 (Eubacteria)의 Spi-rochaetales에 속하는 Treponema pallidum (Tpa)와 Borrelia burgdorferi (Bbu)가 고세균과 유연관계가 높게 나타나는 등 차이점도 보였다. Uridylate kinase를 이용한 분류는, 아주 높은 보존성에 의해서 생기는 16S rRNA 유전자를 이용한 문제점을 보완하여 원핵생물의 정확한 분류에 기여할 수 있을 것으로 사료되었다.

• 한국미생물·생명공학회지
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• 제37권3호
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• pp.189-196
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• 2009

Bacteria were isolated from roots of plants belonging to family Solanaceae and Gramineae, inhabited in Dokdo island. Fifty six endospore-forming bacteria grown on tryptic soy broth (TSB) agar medium and 23 nitrogen-fixing bacteria (NFB) grown on nitrogen free agar medium were isolated, respectively. The isolates were partially identified by analyzing the 16S rDNA and categorized into phylogenetic groups. The 16S rDNA sequences of each identified isolates were compared with sequences of each type strains to analyze phylogenetic relationship by phylogenetic tree. As a result, endospore-forming bacteria and nitrogen-fixing bacteria were classified into 4 and 6 lineage groups, respectively. Among these isolated, 18 were presumed to be novel species candidates based on the similarity (lower than 98%) analysis of the l6S rDNA sequences.

• The Plant Pathology Journal
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• 제18권2호
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• pp.98-101
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• 2002

Using phytoplasma universal primer pair Pl and P7, a fragment of about 1.8 kb nucleotide sequences of 16S rRNA gene and 16S-23S rRNA intergenic spacer region, and a portion of 23S rRNA gene of jujube witches'broom (JWB) and mulberry dwarf(MD) phytoplasmas were determined. The nucleotide sequences of JWB and MD were 1,850 bp and 1,831 bp long, respectively. The JWB phytoplasma sequence was aligned with the homologous sequence of MD phytoplasma. Twenty-eight base insertions and nine base deletions were found in the JWB phytoplasma sequence compared with that of MD phytoplasma. The similarity of the aligned sequences of JWB and MD was 84.8%. The near-complete 16S rRNA gene DNA sequences of JWB and MD were 1,529 bp and 1,530 bp in length, respectively, and revealed 89.0% homology. The 16S-23S rRNA intergenic spacer region DNA sequences were 263 bp and 243 bp in lengths respectively, while homology was only 70% and the conserved tRNA-lle gene of JWB and MD was located into the intergenic space region between 16S-23S rRNA gene. The nucleotide sequences were 77 bp long in both JWB and MD, and showed 97.4% sequence homology. Based on the phylogenetic analysis of the two phytoplasmas, the JWB phytoplasma belongs to the Elm yellow phytoplasma group (16S rV), whereas, the MD phytoplasma belongs to the Aster yellow group (16S rI).

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.428-434
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• 2001

A viscous substance producer strain BS62, which was isolated from conventional Chungkookjang, was examined for its productivity of levansucrase and levan during soybean fermentation at $37{\circ}C$. After one day of cultivation, the enzyme activity reached the highest level, 8 units $ml^{-1}$. Extracts of fermented soybeans were precipitated by ethanol and hydrolyzed by either 0.1 N HCl or invertase, and the hydrolyzates were analyzed using thin layer and ion chromatographies. Fructose was the only sugar detected. This suggest that fructose was derived from the levan produced by the strain BS62 during soybean fermentation. The aerobic, endospore-forming bacterium BS62 was identified as a Bacillus subtilis sp., based on the composition of its cellular fatty acids and phylogeny, which was determined by its 16S rDNA sequence.

• 한국토양비료학회지
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• 제33권4호
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• pp.266-274
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• 2000

토양과 작물근계의 유용미생물을 이용하여 작물생산성을 증대하고 병충해의 생물학적 방제를 위해서는 토양-근계의 미생물군집을 분석하고 그 기능을 밝히는 것이 전제가 되어야한다. 그러나 희석평판법으로는 극히 일부분만이 배양된다는 점을 고려할 때, 생존하지만 배양 불가능한 미생물의 군집 분석도 반드시 병행할 필요가 있다. 따라서 본 연구에서는, 고추재배지의 토양, 근권토양, 근면의 세균군집 구조해석을 위해서, 배양을 거치지 않고 각 시료로부터 직접 DNA를 추출하여 PCR증폭, 16S rDNA cloning, sequencing, 계통 해석을 행했다. 그 결과, 토양중에는 근권세균보다 미지의 동정이 되지 않는 세균이 우점하고 있었다. 27 clones 중에서 16 clones이 그램음성세균의 대표격인 Proteobacteria였으며, 방선균 등이 속해있는 고(高) G+C 그램양성세균군은 1 clone이 검출되었다. 그 외는 CFB 군이 2 clones, Verrucomicrobia가 1 clone이었고, Nitrospira가 1 clone이었으며 4 clones은 어느 군에도 속하지 않았다.

• Animal Systematics, Evolution and Diversity
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• 제38권1호
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• pp.26-33
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• 2022

Two Pseudopolydora polychaetes, P. bassarginensis and P. reticulata, originally described from Peter the Great Bay in Russia and Taiwan, respectively, were recorded firstly in Korea with DNA information. Two species are known to have distinct morphological characteristics that are separated from other Pseudopolydora species. They are characterized by reticulate pigmentations on the dorsal sides of the anterior chaetigers, a longitudinal black band-like pigmentation on the caruncle, and black paired spots on the ventral sides of the anterior chaetigers. These two species can be distinguished morphologically from each other by the length of the caruncle. Methyl green staining pattern of the species is a good method for delimiting Pseudopolydora species. The partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA (16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) from Korean specimens of the two species were determined. The morphological descriptions and images of the two Pseudopolydora species are provided.

• Journal of Microbiology
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• 제38권1호
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• pp.11-17
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• 2000

A new method was developed for the rapid analysis of diverse bacterial species in the natural environment. Our method is based on PCR-single-strands-conformation polymorphism (PCR-SSCP) and selective isolation technique of single-stranded DNA. Variable V3 fragments of 16S rDNA were amplified by PCR with bacterial 16S rDNA primers, where one of the primers was biotinylated at the 5'-end. The biotinylated strands of the PCR products were selectively isolated by using streptavidin paramagnetic particles and a magnetic stand, to prevent SSCP analysis producing heteroduplexes from heterogeneous DNA samples. The selected strands were separated by electrophoresis on a polyacrylamide gel, and detected by silver staining. Analysis of PCR products from 8 bacterial strains demonstrated their characteristic DNA band patterns. In addition, changes in the structure of the bacterial community and species diversity in the microcosm treated with phenol could be monitored. After 3 weeks of incubation, phenol and its intermediate, 2-hydroxy-muconic-semialdehyde, were degraded by indigenous bacteria. These dominating bacterial populations were identified as strong bands on an SSCP gel. Therefore, this study provides useful tools for microbial community analysis of natural habitats.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.810-814
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• 2003

원핵생물 (procaryote)의 분류에 16S rRNA 유전자가 많이 이용되어 있으나 제한된 해상력과 유전자의 수에 차이가 있는 등의 문제가 있어 이를 보완할 수 있는 새로운 생체분자를 찾고 그 분류 결과는 16S rRNA의 결과와 비교하였다. COG(clusters of orthologous of protein) 알고리즘으로 42종의 원핵생물 (procaryote)에서만 발견되는 transcription elongation factor (COG0195), bacterial DNA primase (COG0358) 그리고 uridylate kinase (COG0528)를 구하였다. 이중 유사도와 유전자수를 바탕으로 새로운 분류의 키로 uridylate kinase를 설정하여 분석한 결과 16S rRNA 유전자 결과와 유사점과 차이점을 보여, uridylate kinase를 이용한 분류가 16S rRNA 유전자를 이용한 분류의 문제점을 보완하여 원핵생물의 정확한 분류에 기여할 수 있을 것으로 사료되었다.

• International Journal of Oral Biology
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• 제41권4호
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• pp.199-208
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• 2016

The aim of this study was to identify the non-Aggregatibacter actinomycetemcomitans bacteria grown on the tryptic soy-serum-bacitracin-vancomycin (TSBV) medium, an A. actinomycetemcomitans selective medium. A total of 82 unidentified bacterial isolates from the oral cavities of a Korean population were kindly provide by the Korean Collection for Oral Microbiology. All the clinical isolates were grown on TSBV medium and bacterial DNA purified from each isolate was subjected to PCR with universal primers specific for bacterial 16S rRNA genes (16S rDNAs) sequence. The each bacterial 16S rDNA was amplified by PCR and the nucleotide sequences of it was determined by the dideoxynucleotide chain termination method. They were identified by 16S rDNA sequence comparison method at the specie-level. The data showed that Neisseria spp. (42 strains), Fusobacterium spp. (10 strains), Capnocytophaga spp. (8 strains), Propionibacterium acnes (5 strains), Aggregatibacter aprophilus (4 strains), Campylobacter spp. (5 strains), Veillonella dispar (3 strains), Streptococcus sp. (1 strain), Haemophilus parainfluenzae (1 strain), Leptotrichia wadei (1 strain), Morococcus sp./Neisseria sp. (1 strain), and Staphylococcus sp. (1 strain) were identified. These results could be used to develop a new A. actinomycetemcomitans-selective medium which is more effective than the TSBV medium in future studies.

• 미생물학회지
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• 제46권3호
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• pp.296-302
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• 2010

남조세균 Microcystis (Cyanobacteria, Chroococcales)는 담수 녹조원인 생물의 하나로써 일부 종은 microcystin이라는 간 독소를 분비한다. 따라서 담수 수질관리 및 보건위생 측면에서 이들에 대한 관리가 필요하다. 본 연구는 Microcystis 분자 검출을 위한 신규 마커로 RNA polymerase beta subunit (rpoB) 유전자 염기서열을 분석하여 이들의 분자적 특성을 규명하였다. Microcystis rpoB 유전자는 16S rRNA보다 염기 유사도와 유전거리에서 큰 변이가 있는 것으로 조사되었으며, 통계적으로 유의한 차이를 보였다(Student t-test, p<0.05). Parsimony 분석을 통해 rpoB 유전자가 16S rRNA 유전자보다 2배 이상 빠르게 진화하는 것으로 파악되었다. 또한 rpoB 유전자 phylogeny 분석에서 16S rRNA tree 보다 M. aeruginosa 균주를 명확하게 구분해 주었다. Microcystis가 속하는 Chroococcales 목은 염색체 안에 2개 정도의 rRNA 오페론이 있고 rpoB 유전자는 1개 있는 것으로 조사되었다. 본 연구결과는 rpoB 유전자가 Microcystis의 분자계통분류 및 분자검출 마커로 유용하다는 것을 제시해 준다.