• Journal of Yeungnam Medical Science
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• 제19권1호
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• pp.1-10
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• 2002

With the establishment of rapid sequence analysis of 16S rRNA and the recognition of its potential to determine the phylogenetic position of any prokaryotic organism, the role of 16S rRNA similarities in the present species definition in bacteriology need to be clarified. Comparative studies clearly reveal the limitations of the sequence analysis of this conserved gene and gene product in the determination of relationship at the pathogenic strain level for which DNA-DNA reassociation experiments still constitute the superior method. Since today the primary structure of 16S rRNA is easier to determine than hybridization between DNA strands, the strength of the sequence analysis is to recognize the level at which DNA pairing studies need to be performed, which certainly applies to similarities of 97% and higher.

• 한국식품과학회지
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• 제32권6호
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• pp.1331-1335
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• 2000

김치 젖산균인 WL6는 API kit 또는 Biolog system방법에 의하여 동정한 결과, Leuconostoc mesenteroides ssp. cremoris, Leu. mesenteroides ssp. dextranicum 또는 Lactobacillus bifermentans로 나타나 동정되지 않았다. 그러나, pepN gene과 16S rRNA gene으로부터 2개의 specific-sequence primer set을 제조하여 PCR 방법으로 증폭한 후에 표준균주들과 비교한 결과, WL6는 Lactobacillus bifermentans로 추정되었다.

• 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).

• 미생물학회지
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• 제30권6호
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• pp.479-482
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• 1992

The sequence of the cytoplasmic 5S-rRNA from Trimorphomyces papilionaceus, a basidiomycetous yeast, was determined by the direct chemical method for sequencing RNA and compared to known 5S rRNA sequences of 19 basidiomycetous fuungi. There were 26 nucleotide differences between T. papilionaceus and Tremella mesenterica both of which belong to the Tremellaceae of the Tremellales. Based on Knuc values, the closest fungus was Tilletiaria anomala, another basidiomycetous yeast which belong to the Sporbolomycetaceae of the Sporobolomycetales. T. papilionaceus did not show any significant phylogenetic relationship with other fungi.

• 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.

• 한국패류학회지
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• 제13권1호
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• pp.1-7
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• 1997

한국산 가리비, 큰가리비(Patinopecten yessoensis)와 주문진가리비(Chlamys swifti), 2종에 대한 28S ribosomal RNA 유전자의 PCR- 산물을 이용 RFLP 및 염기서열을 밝히고, 이미 보고된 2과 3종의 염기서열과 상동성을 비교 분석하였다. 그 결과 28S rRNA유전자를 이용하여 7가지 제한효소를 처리한 PCR-RFLP의 종간 차이에서 Taq I 제한효소에서만 차이를 볼 수 있었다. 한편 두종간에 28S rRNA유전자의 D1 부위의 염기서열에서 231개 부위 중 14군데에서 변이를 보였다.

• 생태와환경
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• 제55권4호
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• pp.352-359
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• 2022

국내 서식하는 수서 생물(식물플랑크톤, 동물플랑크톤, 저서대형무척추동물, 어류)에 대한 eDNA 연구에 주요 이용되는 유전자인 12S rRNA와 16S rRNA, 18S rRNA, COI, CYTB를 대상으로 속(Genus) 수준의 등록 현황을 조사하였다. 그 결과 식물플랑크톤과 동물플랑크톤은 18S rRNA에서 가장 높은 등록 속 비율을 보였으며, 저서무척추동물은 COI에서 가장 높은 등록 속 비율을 확인하였다. 어류에서는 18S rRNA를 제외한 모든 유전자에서 90%에 가까운 높은 비율을 보였다. 분류군에 따른 우점 생물의 상위 20속에 대한 유전자 등록 현황은 식물플랑크톤은 18S rRNA에서 19속이, 저서무척추동물은 COI에서 18개 속이 등록되어 있었다. 어류에서는 12S rRNA, 16S rRNA, CYTB에서 상위 20의 모든 유전자 염기서열이 존재함을 확인하였다. 본 자료 분석을 통하여 각 분류군별 eDNA 연구에 적합한 유전자 데이터베이스의 양적인 정보를 파악하였다.

• 미생물학회지
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• 제41권2호
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• pp.125-128
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• 2005

S. chungbukensis DJ77로부터 16S rRNA유전자의 염기서열을 분식하였다. 염기서열은 총 1,502 bp로 2000 년에 등록된 부분 서열(1,435 bp)보다 5' 방향과 3' 방향으로 29 bp와 37 bp 길이만큼 각각 확장하였으며, 1 bp가 추가로 삽입되었다. E. coli의 16S rRNA유전자를 모델로 이차구조를 제작하였으며, 네 부위가 특이적임을 발견하였다. Sphnigomonas spp.의 16S rRNA 서열과 S. chungbukensis DJ77의 다중서열검색 결과, Sphingomonas종에서만 나타나는 보존부위와 가변부위를 발견할 수 있었다. 특히, Campylobacter jejuni에서만 나타나는 것으로 알려진 긴 stem loop구조가 서열은 조금 다르지만 구조적 일치를 보이는 유사한 구조를 S. chungbukensis DJ77에서도 발견하였다. 결과적으로, 다중서열검색을 통해 제작한 계통수와 nucleotide signatures분석에 근거하여 S. chugukensis DJ77을 cluster II (Sphingobium)로 분류하였다.

• Animal cells and systems
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• 제4권1호
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• pp.31-37
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• 2000

The genetic variations among six species of Rana from Korea (R. nigro-maculata, R. piancyi, R. dybowskii, R. sp, R. rugosa type A, B and R. amurensis) were investigated using 499 bases of mitochondrial DNA sequences for ND2 (NADH dehydrogenase subunit 2) gene and $tRNA^{Trp}$ gene. Partial sequences of ND2 gene (427 bp) and full sequences of $tRNA^{Trp}$ gene (73 bp) were identified. The level of sequence divergences ranged from 0.2 to 5.2% within species and 4.9-28.0% among 6 species of the genus Rana. The $tRNA^{Trp}$ gene of the genus Rana was composed of 77 nucleotides which showed a two dimensional "cloverleaf" structure. The secondary structure of $tRNA^{Trp}$ was not found compensatory changes which could potentially confound phylogenetic inference. In the neighborjoining tree, brown frogs were clustered first with the level of sequence divergence of 13.20% between R. amurensis and R. dybowskii, and 9% between R. dybowskii and R. sp. supported by 99% bootstrap iterations, respectively. R. nigromaculata and R. plancyi were clustered into another group with 5.1% divergence supported by 100% bootstrap iteration. R. rugosa A 8nd B types were grouped by 4.9% divergence and clustered into the last group with other two groups with 100% bootstrap iterations.

• ALGAE
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• 제27권2호
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• pp.75-82
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• 2012

$Arthrospira$ $platensis$ and $Arthrospira$ $maxima$ are species of cyanobacteria used in health foods, animal feed, food additives, and fine chemicals. This study conducted a comparison of the 16S rRNA gene and $cpcBA$-intergenic spacer ($cpcBA$-IGS) sequences in $Arthrospira$ strains from culture collections around the world. A cluster analysis divided the 10 $Arthrospira$ strains into two main genotypic clusters, designated I and II, where Group I contained $A.$ $platensis$ SAG 86.79, UTEX 2340, $A.$ $maxima$ KCTC AG30054, and SAG 49.88, while Group II contained $A.$ $platensis$ PCC 9108, NIES 39, NIES 46, and SAG 257.80. However, although $A.$ $platensis$ PCC 9223 belonged to Group II-2 based on its $cpcBA$-IGS sequence, this strain also belonged to Group I based on its 16S rRNA gene sequence. Phylogenetic analyses based on the 16S rRNA gene and $cpcBA$-IGS sequences showed no division between $A.$ $platensis$ and $A.$ $maxima$, plus the 16S rRNA gene and $cpcBA$-IGS sequence clusters did not indicate any well-defined geographical distribution, instead overlapping in a rather interesting way. Therefore, the current study supports some previous conclusions based on 16S rRNA gene and $cpcBA$-IGS sequences, which found that $Arthrospira$ taxa are monophyletic. However, when compared with 16S rRNA sequences, $cpcBA$-IGS sequences may be better suited to resolve close relationships and intraspecies variability.