• Korean Journal of Medicinal Crop Science
• /
• v.14 no.3
• /
• pp.178-182
• /
• 2006

This study was conducted to investigate the variation in sequence, the base composition and the sequence similarity of 18S rDNA (18S ribosomal RNA coding region) in the 10 Polygonatum spp. collections. The entire 18S rDNA region of 10 Polygonatum spp. collections ranged from 913 bp to 914 bp. There were 8 variable sites in the entire 18S region, and they were attributable to nucleotide substitution and deletion. $T{\rightarrow}C$ transition happened in 4 sites, and $A{\rightarrow}G$ transition happened in 1 site. $C{\rightarrow}A$ transversion happened in 1 site, and deletion happened in 2 sites. Transition rates were five times that of transversion. Base compositions of 18S rDNA were $23.09{\sim}23.33%$ in adenine, $23.33{\sim}23.52%$ in guanine, $25.60{\sim}25.85%$ in thymine and $27.38{\sim}27.79%$ in cytosine. The A + T content of 18S rDNA of 10 Polygonatum spp. collections averages 48.99%, ranging from 48.80% to 49.18%, and the G + C content averages 51.01%, ranging from 50.82% to 51.20%. Pairwise sequence comparisons indicated that 18S rDNA sequence similarity ranged from 99.7% to 100%.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.36 no.1
• /
• pp.35-38
• /
• 2003

Nuclear 18S ribosomal RNA gene (185 rDNA) from the aquaculturable seaweed Porphya tenera (Bangiales, Rhodophyta) was amplified using the polymerase chain reaction and its sequence was analysed. Complete 185 rDNA has an 1,822 bp exon and a 510 bp intron. The G+C contents of exon and intron were $48.68\%\;and\;54,90\%,$ respectively. The exon sequence showed $99.6\%$ homology to the GebBank accession number AB029880 of the Japanese P. tenera. The intron region that is inserted upstream between 568 and 1,079 showed $43.6\%$ homology to the AB029880.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.6
• /
• pp.633-638
• /
• 2002

Nuclear 18S ribosomal RNA gene (185 rDNA) from the aquaculturable seaweed Porphya yezoensis (Bangiales, Rhodophyta) was amplified using the polymerase chain reaction and its sequence was analysed. Complete 185 rDNA has an 1823 bp exon and a 514 bp intron. The G+ C contents of exon and intron were $48\%$ and $51.4\%$, respectively. The exon sequence showed $99.5\%$ homology to the GenBank accession number AB013177 of the Japanese p. yezoensis. The intron region that was inserted upstream between 568 and 1083 showed $93.4\%$ homology to the AB013177.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.50 no.4
• /
• pp.447-452
• /
• 2017

In this study, we tried to identify a sea anemone collected from the coast of Gijang, Busan. The anemone was morphologically similar to species belonging to the genus Anthopleura, but its morphological characteristics did not allow for confirmed identification to species level. Multiple genes from mitochondrial cytochrome oxidase III, 12S and 16S rRNA, and nuclear 18S and 28S rRNA, were amplified for multilocus sequence typing (MLST) analysis using genomic DNA extracted from the sampled anemone and a different primer set. Based on the MLST analysis, the anemone obtained in this study was identified as Anthopleura artemisia. Also, the sequence of internal transcribed spacer-2 was most closely related to A. artemisia, indicating that this single region might be useful for anemone identification. This study shows significance of molecular identification for sea anemones, and will be helpful in studies of sea anemone identification using genotyping-by-sequencing.

• The Korean Journal of Malacology
• /
• v.21 no.2 s.34
• /
• pp.147-161
• /
• 2005

To elucidate the phylogenetic relation of the superfamily Veneroidea, we obtained partial 28S rRNA sequences of 14 heterodonts and three pteriomorphs which were collected from Korea and the sequence data of related taxa from GenBank, and analyzed maximum parsimony with PAUP program 750 of the nucleotide positions were variable, 560 of which were informative under conditions of parsimony. Total tree length was 2,765, and consistency index, homoplasy index (HI), and Retention index was 0.4843, 0.5157, and 0.6291, respectively. Intraspecific variation of 28 rRNA of Corbicula fluminea and Sinonovacula constricta was 3.1% and 1.3%, respectively. Pitarinae-Cyclininae-Meretrinae group had a clade and Samaranginae, Chioninae, and Dorsininae were clustered.

• Korean Journal of Ichthyology
• /
• v.18 no.2
• /
• pp.78-86
• /
• 2006

We examined the genetic diversity in intra-populations of Korean shiner, Coreoleuciscus splendidus, in six major rivers (Bukhan, Namhan, Geum, Osipcheon, Nakdong and Seomjin river) of Korea based on two different mitochondrial genes, the mitochondrial cytochrome b and the 16S rRNA. Analysis of sequence variation in a 657-bp segment of the mitochondrial cytochrome b gene revealed deep divergence among populations (98.2~99.9%) and high genetic diversity from geographically isolated populations. Intra-specific variation in this 697-bp segment of the 16S rRNA gene sequences was very low and nearly identical. Six isolate populations of C. splendidus showed a high similarity (97.7%~99.7%). This result may be indicative of a complex history of connection and isolation of the rivers in the Korea peninsula.

• Proceedings of the Korean Society of Sericultural Science Conference
• /
• 2003.10a
• /
• pp.24-27
• /
• 2003

The ribosomal RNA gene (rDNA) cluster was located in the nucleolus organizer and was genetically determined as one locus. We speculated by using sequence differences in the functional rDNA unit that the segregation time between Chinese and Japanese types of B. mandarina is about three million years ago. The differences of the amount of inserted non-LTR retrotransposons, R1Bm and R2Bm, in rDHA cluster were used for the identification of B.mori strains. (omitted)

• Journal of Life Science
• /
• v.22 no.7
• /
• pp.987-990
• /
• 2012

Mungbean sprout rot is one of the most serious problems of the commercial mungbean sprout industry. In this study, 70 strains of mungbean sprout rot pathogens were isolated from rotten sprouts at different time intervals. The pathogenicity of the isolated pathogens was tested. The highly pathogenic strain (YV-St-033) was identified as Pseudomonas sp. by 16S rRNA gene sequencing. In phylogenetic analysis, the YV-St-033 strain was grouped with P. mosselii, P. putita, P. fluorescens, P. entomophila, and P. lecoglossicida. The results of the 16S rRNA gene sequence analysis revealed that the YV-St-033 strain shared the highest sequence identity (more than 99%) with the P. mosselii R10 strain. The mungbean lines of Yeungnam University germplasm were screened against the YV-St-033 strain. Based on the growth rate of the sprouts after 3 days of inoculation with the pathogen, the YV148 line was highly resistant to the pathogen. The remaining lines were either partially or fully infected. The highly resistant line YV 148 is suitable for future breeding programs due to their thin sprouts and fast growing nature.

• Journal of Animal Science and Technology
• /
• v.46 no.6
• /
• pp.937-946
• /
• 2004

Duroc is widely used to improve the meat quality and productivity. To elucidate the phylogenetic relation and the sequence specificity for the maternal property, the complete sequence of mitochondrial genome was determined and the population diversity of Duroc was investigated in this study. The length of mtDNA tested is 16,584-bp. There are several insertion/deletion mutations in the control region and coding regions for tRNA and rRNA, respectively, but not in peptide-coding regions. Four peptide-coding genes(COⅡ, COⅢ, ND3 and ND4) showed incomplete termination codon sequences such as T--, and two(ND2 and ND4L) did alternative initiation codons(AIC), respectively. Especially, the initiation codon sequences of ND2 gene were polymorphic in this population. Polymorphisms were detected in 11-bp duplication motif within control region as well as ND2 and CYTB. Variation patterns observed from the tests on three mtDNA regions were linked completely and then two haplotypes obtained from combining the data dividing this population. Duroc mtDNA is observed at the European pig cluster in the phylogenetic tree, however, the results from the population analyses supported previous opinions. This study suggests that the breed Duroc was mainly originated from the European pig lineage, and Asian lineage was also used to form the pig breed Duroc as maternal progenitors.

• Korean Journal of Environmental Biology
• /
• v.31 no.2
• /
• pp.158-164
• /
• 2013

A microcystin-degrading bacterium was isolated from Daechung reservoir, Korea. The isolated bacterium was identified as Microbacterium sp. by 16S rRNA gene sequence analysis, and designated as Microbacterium sp. MA21. This strain degraded cyanobacterial hepatotoxin, microcystin-LR, over 80% when incubated at $30^{\circ}C$ for 12 hr in R2A medium. Two unknown metabolites of microcystin were also identified during the degradation process. Although only Sphinogomonas and Actinobacteria have been known to degrade microcystin previously, this is the first report that Microbacterium sp. MA21 could degrade microcystin.