• Korean Journal of Ecology and Environment
• /
• v.46 no.2
• /
• pp.301-309
• /
• 2013

Between May and August 2012, a massive cyanobacterial bloom with Anabaena has been occurred throughout the North Han River. Sampling was conducted at one station on each lake, L. Uham, L. Cheongpyung, and L. Paldang, where occurred a dense bloom, in 13 July. According to the microscopic examination, the blooms was dominated by one specific filamentous cyanobacterium Anabaena and other phytoplankton. Morphologically, previous literature proven that this Anabaena species is A. crassa (Lemmermann) Komark.-Legn. & Cronberg. However, identification of species in a mixed population is complicated due to limited morphological differences. Therefore, with live sample including trichome, akinete and heterocyst, the sequences of 16S rRNA gene of Anabaena isolates were cloned and analyzed, and three 16S rRNA gene sequences of 1188~1520 bp in length were obtained. It was shown from the homologous analysis results that the obtained 16S rRNA sequences were highly homologous to the relevant sequences of A. crassa in GenBank. The 16S rRNA sequences of 63 species were retrieved from GenBank, and the phylogenetic tree was constructed by using these sequences.

• Journal of Marine Life Science
• /
• v.5 no.1
• /
• pp.17-24
• /
• 2020

We have identified a heat shock protein 70 gene from freshwater snail, Semisulcospira coreana. The freshwater snail HSP70 gene encode a polypeptide of 639 amino acids. Based on bioinformatic sequence characterization, HSP70 gene possessed three classical signature motifs and other conserved residues essential for their functionality. The phylogenetic analysis showed that S. coreana HSP70 had closet relationship with that of golden apple snails, Pomacea canaliculata. The HSP70 mRNA level was significantly up-regulated in response to thermal and salinity challenges. These results are in agreement with the results of other species, indicating that S. coreana HSP70 used be a potential molecular marker in response to external stressors and the regulatory process related to the HSP70 transcriptional response can be highly conserved among species.

• Journal of Mushroom
• /
• v.8 no.1
• /
• pp.27-32
• /
• 2010

This study was carried out to analyze the genetic relationships among 22 strains of Sparassis crispa, which were collected from various regions of worldwide. The cleaved amplified polymorphic sequence were obtained from the ribosomal DNA ITS regions of each strain. Based on the sequence analysis, the presence of five different groups were observed. Most strains shared the high nucleotide sequence similarity (about 90%) to each other, except only one strain, KACC50866. Nucleotide sequence similarity of KACC50866 was below 10% to other strains, indicating the genetic relatedness of strain KACC50866 was low compared to other strains. More works such as mitochondria genome analysis should help to determine the precise genetic diversity of S. crispa strains.

• Korean Journal of Ichthyology
• /
• v.21 no.4
• /
• pp.291-298
• /
• 2009

A molecular phylogenetic relationship inferred from mitochondrial cytochrome b gene sequence was developed based on analysis of Zacco species distributed in Korea as well as China, Japan and Taiwan. A maximum parsimony (MP) tree showed that Korean Z. temminckii and Z. koreanus formed a monophyletic clade, but the populations of Z. temminckii and Z. koreanus in the 'South Korean Subdistrict' region had genetic similarity with Japanese Z. temminckii. Korean Z. platypus had a closer relationship with Japanese members of the clade than with Chinese Z. platypus, which was more closely related to Opsariichthys uncirostris amurensis. The analysis of neighbor joining (NJ) tree may support a hypothesis that the clade of Z. platypus had genetically diverged from the common ancestor of Zacco species comprising Z. koreanus, Z. temminckii, Z. sieboldii and other species; thereafter a cladogenesis of Z. koreanus and Z. temmminckii had occurred from the ancestor of Z. sieboldii. Moreover, the Chinese Z. platypus had diverged far from the Korean Z. platypus and formed a phylogenetic relationship with O. uncirostris amurensis. Therefore, a more detailed study of the taxonomy and systematics of Zacco species in regard to their zoogeographical distributions is needed.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.3
• /
• pp.543-552
• /
• 2014

Papain family중 하나인 cysteine protease는 근골격계 질환 치료를 위한target molecule로 인식 되어왔으며 Cathepsin B 는 단백질 분해의 초기과정에 관여하는 cysteine proteases 중 하나이다. 본 연구는 넙치의 cathepsin B 유전자의 발현 양상과 넙치 cathepsin B(PoCtB)의 클로닝, 발현 및 효소특성을 분석하였다. cDNA Library Screening을 이용하여 넙치의 cDNA를 클로닝하였다. 넙치의 동정된 cathepsin B 유전자는 993bp의 open reading frame과 330개의 아미노산으로 이루어져있다. Cathepsin B의 propeptide region 내에 GNFD motif와 occluding loop 가 존재함으로써 이것이 명백하게 cathepsin B group이라는 것을 보여주며, 계통 유전학적 분석 결과 다른 종의 cathepsin B에 비해 초창기에 분화되어 나온 것으로 사료된다. mature enzyme인 maPoCtB은 fusion protein인 glutathione S-transferase를 포함하는 pGEX-4T-1 vector에 삽입하여 E.coli 균주인 $DH5{\alpha}$ 내에 발현시켰다. 재조합 단백질인 PoCtB을 과발현 시킨 결과 53kDa의 분자량을 가진다. 넙치 cathepsin B 활성은 Z-Arg-Arg-AMC와 같은 fluorogenic 펩타이드 기질을 이용하여 측정되었고 적정 pH는 pH.7.5 이다.

• Korean Journal of Ichthyology
• /
• v.33 no.4
• /
• pp.217-225
• /
• 2021

The family Platycephalidae is a taxonomic group of economically important demersal flathead fishes that predominantly occupy tropical or temperate estuaries and coastal environments of the Indo-Pacific oceans and the Mediterranean Sea. In this study, we for the first time analyzed the complete mitochondrial genome (mitogenome) of the flathead Platycephalus cultellatus Richardson, 1846 from Vietnam by Next Generation Sequencing method. Its mitogenome was 16,641 bp in total length, comprising 13 protein-coding genes (PCGs), two ribosomal RNA genes, and 22 transfer RNA genes. The gene composition and order of the mitogenome were identical to those of typical vertebrates. The phylogenetic trees were reconstructed based on the concatenated nucleotide sequence matrix of 13 PCGs and the partial sequence of a DNA barcoding marker, cox1 in order to determine its molecular phylogenetic position among the order Scorpaeniformes. The phylogenetic result revealed that P. cultellatus formed a monophyletic group with species belonging to the same family and consistently clustered with one nominal species, P. indicus, and two Platycephalus sp. specimens. Besides, the cox1 tree confirmed the taxonomic validity of our specimen by forming a monophyletic clade with its conspecific specimens. The mitogenome of P. cultellatus analyzed in this study will contribute valuable information for further study on taxonomy and phylogeny of flatheads.

• The Korean Journal of Mycology
• /
• v.47 no.4
• /
• pp.329-335
• /
• 2019

Endophytic fungal strains were isolated from the sterilized roots of a medicinal plant, Ligusticum chuanxiong and identified based on morphological characteristics and molecular analysis of internal transcribed spacer, large subunit rDNA, and beta-tubulin DNA regions. Our results confirmed the presence of Pithomyces chartarum and Plectosphaerella niemeijerarum in the fungal strains. To the best of our knowledge, the fungal strains have not been reported in Korea. In this report, we describe morphological characteristics and phylogenetic trees of these endophytic fungal strains.

• Journal of Life Science
• /
• v.14 no.4
• /
• pp.593-607
• /
• 2004

The nucleotide sequence for a nuclear-encoded small subunit rDNA (SSU rDNA) was determined for 43 species of the class Dinophyceae, including harmful algae Cochlodinium polykrikoides and Gyrodinium aureolum. These sequences and data analyses were performed by parsimony, distances and maximum likelihood methods in PHYLIP (Phylogenetic Inference Package) version 3.573c. The species Noctiluca scintillans, Gonyaulax spinifern and Crypthecodinium cohnii occupied a basal position within the Dino- phyceae in our analyses. The genera Alexandrium and Symbiodinium were monophyletic (supported by a bootstrap value of >70%), whereas the genera Gymnedinium and Gyrodinium formed polyphyletic nodes, for which bootstrap support was strong (>70%) in the neighbor-joining and maximum likelihood methods except for the PHYLIP parsimony analysis (=59%). The sequence divergence between G. aureolum and G. dorsum/ G. galathenum was the largest at 7.4% (45 bp), whereas G. aureolum and G. mikimotoi showed an extremely low value of genetic divergence of 0.9% (5 bp). The genetic divergence between C. polykrikoides and G. aureolum was a low value of 5.2% (31 bp). In the phylogenetic analysis, the placement of G. aureolum and C. polykrikoides was closer to the genus Gymnodinium than to the genus Gyrodinium, which was supported by a moderate bootstrap value.

• Journal of Plant Biotechnology
• /
• v.40 no.4
• /
• pp.192-197
• /
• 2013

This study examined the phenotypic and molecular characteristics of the $2^{nd}$ clone ($T_0V_2$) plants of LeLs-antisense gene-transgenic chrysanthemum line (LeLs80) that exhibited non-branching, proving the relevance of these characteristics as a factor for use in environmental risk assessment. Results of the Southern blot analysis showed that three copies of the LeLs-antisense gene were introduced into the transgenic line, and northern analysis showed that the transcripted gene was normally expressed in the transgenic line. A flanking T-DNA sequencing method was used to determine that sequences of 184 and 464 bps flanked the LeLs-antisense gene in the transgenic line. These sequences, respectively, matched the 35S promoter for expression of the npt II gene and the NOS terminator for expression of the LeLs-antisense gene within the pCAMBIA 2300 vector.