• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.515-523
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• 2001

The dinoflagellates have some primitive nuclear features and are evolutionarily intermediate between prokaryotes and eukaryotes. The small subunit ribosomal RAN gene, the 5.8S ribosomal RNA gene, and the internal transcribed spacer (ITS) of Gonyaulax polyedra were cloned, and their sequences were analyzed to better understand their evolutionary position. The small subunit ribosomal RNA gene was 1,794 nt long, the large subunit ribosomal RNA gene was approximately 3,500 nt long, and the 5.8S ribosomal RNA gene was 159 nt long. The first internal transcribed spacer (ITS1) was 191 nt long, and the second internal transcribed spacer (ITS2) was 185 nt long. The intergenic spacer of the ribosomal RNA gene (IGS) was about 2,200 nt long, indicating that 5,800 nt of transcribed sequences were separated by roughly 2,200 nt of intergenic spacer. The ribosomal RNA genes were repeated many times and arranged in a head-to-tail, tandemly repeated manner. The repeating unit of ribosomal RNA gene of G. polyedra was proposed to be 8,000 nt long. Based on the lengths of ribosomal RNA, sequence alignments with representative organisms, and phylogenetic analysis on ribosomal RNA, G. polyedra appears to be one of the alveolates branched from the eukaryotic crown and, among dinoflagellates, it seems to not have emerged early.

• Parasites, Hosts and Diseases
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• v.36 no.1
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• pp.47-54
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• 1998

Small subunit ribosomal RNA (SSU rRNA) gene nucleotide sequences of bovine ReiLerin isolates from Korea (KLS and KCB) and japan (JHS) were determined. The genes from each isolate were amplified by the polymerase chain reaction and the approxi- mately 1.8 kb product cloned and sequenced by a modified dideoxynucleotide method. Overlapping gene segments produced with a series of primers were sequenced, resoRting in a complete DNA sequence for both forward and reverse strands of the SSU rRNA genes of each isolate. SSU rRNA gene sequences (termed Type A) were identical among the bovine ReiLeri,n isolates from Korea and the isolate from Japan. A GenBank data library homolo- gy search showed the sequence to be the same as that listed as leiLeyia buKeLi isolated from cattle in Marula, Kenya.

• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.909-917
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• 1998

Six different sequences types(A through E and H) and a subtype(Bl) of the small subunit ribosomal RNA(SSUrRNA) gene were found in bovine Theileria isolates from different areas of Korea and Japan. The sequences were aligned and three hypervariable regions were observed in the nucleotide position ranges 212~231, 261~270 and 632~690. Five of the Theileria isolates yielded sequence type A; these were the field isolates KCB, KCN, and KCJ, and the laboratory stock KLS, all from Korea, and a single isolate from Japan (JHS). This sequence type is identical to the SSUrRNA gene sequence listed for Theileria buffeli (GenBank Accession No. Z15106) from Marula, Kenya. The Korean field isolate KKB yielded only a single sequence type (B), but multiple sequence types were found in some isolates. For example, KCB and JHS isolates yielded both types A and B ; isolate KKW showed types B and H; isolate KCN showed types A, C, and D ; and isolate KCJ showed types A, B, E, and a subtype B1. Finding of the multiple sequences SSUrRNA gene sequences suggests that bovine Theileria isolates from both Korea and Japan may consist of mixed populations.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.382-388
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• 2014

Shortfin eel (Anguilla bicolor pacifica) is a species of commercial importance and its production is greatly affected due to the infection by Heterosporis anguillarum. In this study, we evaluated the effect of H. anguillarum infection on the growth of Shortfin eel. A disease that trunk muscle of cultured shortfin eel, Anguilla bicolor pacifica, were irregular and resulted in death, breakout of the commercial eel culture farm. We observed that the trunk muscle of infected eels were irregular and represented white or yellowish externally. Histopathologically, a great numbers of large or small spores and sporophorocysts were also observed in degenerated muscle layer. The cloning of specific gene of H. anguillarum, encoding small subunit ribosomal RNA (SSU-rRNA) was amplified by the polymerase chain reaction(PCR) from the muscle lesion of diseased eel. The size of clone gene is well matched with the size of small subunit ribosomal RNA of H. anguillarum and thus confirming the infection by H. anguillarum.

• Journal of Microbiology
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• v.38 no.3
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• pp.122-131
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• 2000

Phylogenetic classification of the Aphyllophorales was conducted based on the analysis of nuclear small subunit ribosomal RNA (nuc SSU rDNA) sequence. Based on phylogenetic groupings and taxonomic characters, 16 families were recognized and discussed. Although many of the characters had more or less homoplasies, miroscopic characters such ad the mitic system and clamp, spore amyloidity and rot type appeared to be important in the classification of the Aphyllophorales. Phylogenetically significant families were newly defined to improve the classification of the order Aphyllophorales.

• Mycobiology
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• v.29 no.2
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• pp.73-79
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• 2001

The Polyporaceae is a chaotic mass of genera having poroid hymenophores in the Aphyllophorales. To classify the Polyporaceae into more natural groups, phylogenetic analyses were performed using nuclear small subunit ribosomal DNA sequences. Thirty-six species from the families of the Polyporaceae, the Hymenochaetaceae, the Ganodermataceae, the Corticiaceae, the Bondarzewiaceae, the Meruliaceae, the Steccherinaceae and the Lentinaceae were phylogenetically compared. By performing maximum parsimony analysis, seven phylogenetically meaningful groups were identified and discussed. The hyphal system, presence or absence of clamps, and the type of rot were found as important characters in defining the groups. Each group was phylogenetically significant enough to be a core member of each family when the Polyporaceae was split into smaller and more natural families.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.225-233
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• 2007

To verify which loop regions of 18S rRNA gene are suitable as species-specific genetic markers in ciliates, we analyzed the genetic variation of 18S rRNA gene among 9 Euplotes species (Hypotrichia : Ciliophora). In our result, no inter-specific variation was detected from V1, V3 and V5 regions, and the length of V7 and V8 are 44 bp and 79 bp, respectively, which are too short to make genetic marker. In contrast, V2 and V4 may be good candidate segments of species-specific diagnostic molecular markers because these two regions are most variable ($1.75{\sim}20.61%$) and showed good inter-specific phylogeny. Furthermore, the sequences of V2 and V4 are 123 bp and 306 bp, respectively in length which are enough to make species-specific marker.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.194-199
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• 1995

A portion (7.4 kb) of ribosomal DNA tandem repeat unit from a genome of the mushroom T. matsutake has been cloned. A 1.75 kb EcoRI fragment was cloned first using S. cerevisiae 255 rRNA gene as a probe, and this was then used for further cloning. A chromosomal walking experiment was carried out and the upstream region of the 1.75 kb fragment was cloned using SmaI/BamHI enzyme, the size was estimated to be 5.2 kb in length. Part of the downstream region of the 1.75 kb fragment was also cloned using XbaI/BamHI enzymes. Restriction enzyme maps of three cloned DNA fragments were constructed. Northern hybridization, using total RNA of T. matsutake, and the restriction fragments of three cloned DNAs as probes, revealed that all four ribosomal RNA genes (large subunit[LSU], small subunit [SSU], 5.85 and 5S rRNA genes) are present in the cloned region. The gene organization of the rDNA are regarded as an intergenic spacer [IGS]2 (partial) - SSU rRNA - internal transcribed spacer [ITS]1 - 5.8S rRNA - ITS2 - LSU rRNA - IGS1 -5S rRNA - IG52 (partial).

• YAKHAK HOEJI
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• v.24 no.1
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• pp.1-10
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• 1980

Viomycin inhibited polypeptide biosynthesis, initiation complex formation and translocation of peptidyl-tRNA on ribosomes derived from a sensitive strain of Mycobacterium smegmatis (R-15), but not significantly on ribosomes from viomycin-resistant mutants(R-31 and R-43). The inhibition of translocation was stronger than that of initiation complex formation in the sensitive strain. The binding of [$^{14}C$] tuberactinomycin O, a viomycin analog, to ribosomal particles was studied by Millipore filter method. The sensitive ribosome exhibited higher affinity for the antibiotic than the resistant ribosomes. The resistance was localized on the large ribosomal subunit in a mutant(R-31), and on the small subunit in another mutant(R-43). The binding of the drug to the sensitive ribosomal subunit was markedly reduced by combination with the resistant pair subunit, and the entire ribosome became resistant to the antibiotic.

• Proceedings of the Zoological Society Korea Conference
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• 1998.04a
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• pp.37.1-37
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• 1998

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