• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.699-707
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• 1995

Eurasian yellow perch (Perca fluviatilis) and American yellow perch (Perca flavescens) are known to be endemic species in Eurasia and North America, respectively. The presence of endemic species on each continent suggests their independent evolutionary history. However, because of the morphological similarity, distribution pattern, and only recent fossil record, their divergence time and speciation of the two Perca species has long been controversial. Here, from the comparison of the entire nucleotide sequences of cytochrome b gene, large genetic divergence between the two Perca species is observed although they are morphologically similar each other. Among 1,140 base pairs, interspecific nucleotide differences are found at 130 sites $(11.4\%)$. The differences varies with codon position, showing 22 sites in the first, 5 sites in the second, and 103 sites in the third codon position. Considering the types of nucleotide changes, transitional differences are much more than transversional differences and its ratio turned out to be 5.19. The estimated divergence time of the two Perca species indicates that they were separated each other approximately in the late Miocene period, which implies the long history of speciation. With comparison of the inferred amino acid sequences, strong structural and functional constraints which seem to be maintained by the highly conservative amino acid residues or protein regions, as found in other taxonomic groups of organisms, are also recognized in the cytochrome b of the fishes examined.

• Animal Systematics, Evolution and Diversity
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• v.6 no.1
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• pp.1-16
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• 1990

The skull and superficial cephalis muscles of Coreoleuciscus splendidus Mori was investigated comparatively with other some fishes of the family Cyprinidae to study on the systematic position of this species. Coreoleuciscs splendidus was unique in the morphology of sphenotic process and the urohyal and this species differ from the true bottom dwellers of the subfamily Gobioninae in the strucutre of cephalic lateral-line canals, the relation of parasphenoids with pterotic and prootic, the morphology of urohyal , basihyal , hypobranchial, and , particulary, the configuration of adductor manibulae complex. With reference to the information so far obtained , the taxonomic position of the present species was discussed in the Cyprinidae.

• Journal of Microbiology and Biotechnology
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• v.21 no.6
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• pp.567-573
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• 2011

We investigated the phylogenetic diversity of ammoniaoxidizing bacteria (AOB) in Yellow Sea continental shelf sediment by the cloning and sequencing of PCR-amplified amoA and 16S rRNA genes. Phylogenetic analysis of the amoA-related clones revealed that the diversity of AOB was extremely low at the study site. The majority (92.7%) of amoA clones obtained belonged to a single cluster, environmental amoA cluster-3, the taxonomic position of which was previously unknown. Phylogenetic analysis on AOB-specific 16S rRNA gene sequences also demonstrated a very low diversity. All of the cloned 16S rRNA gene sequences comprised a single phylotype that belonged to the members of uncultured Nitrosospira cluster-1, suggesting that AOB belonging to the uncultured Nitrosospira cluster-1 could carry amoA sequences of environmental amoA cluster-3.

• Journal of Ecology and Environment
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• v.36 no.4
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• pp.407-419
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• 2013

Cyclotella species were collected at 51 sites from July 2010 to June 2013 in Korean coastal waters. A total of five Cyclotella species (C. atomus var. marina, C. baltica, C. litoralis, C. meduanae, and C. meneghiniana) were identified in this study. The diagnostic characteristics for five Cyclotella species are described, focusing on the spacing, position, number of satellite pores of the mantle fultoportula and valve face fultoportula. In addition, we put the salinity ranges of five species of Cyclotella together. Of the five Cyclotella species, C. baltica, C. litoralis and C. meduanae are newly recorded in Korea.

• ALGAE
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• v.19 no.4
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• pp.283-292
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• 2004

Psilothallia is a ceramiaceous red algal. genus that includes three species worldwide: P. dentate, P. siliculosa, and P. striate. The latter two species are limited to Australian waters, and P. dentate occurs in Japan. We here report the detailed morphology of P. dentate, and also determined plastid protein-coding psbA in P. dentate and putative relatives. Psilothallia dentate is distinguished by compressed thalli with alternate-distichous determinate branchlets, six periaxial cells, rhizoidal filaments in axes, cystocarps with 7-8 involucral filaments, spermatangia on branched filaments, and tetrahedrally divided tetrasporangia on branched filaments. Psilothallia dentate is also unusual in that cystocarps, spermatangial clusters, and tetrasporangial tufts are formed on short adventitious indeterminate branches arising on axils of determinate branchlets. The phylogenetic trees of psbA sequences show that P. dentata was nested in a monophyletic Glade comprising Ptilota, Neoptilota, and Plumaria. This result suggests that the taxonomic position of P. dentate may be transferred from the tribe Rhodocallideae to the Ptiloteae.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.167-172
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• 1977

Colony morphology, growth responses on some simple carbon sources and taxonomic position were established for three stock cultures of National Collection of Industrial Bacteria, Scotland. It was confirmed that NCIB 8077 belonged to the Cellulomonas species and that NCIB 8633 and NCIB 8634 belonged to the Pseudomonas species. Taxonomy of other cellulolytic bacteria published on various journals was also discussed.

• Journal of Microbiology and Biotechnology
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• v.7 no.1
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• pp.32-36
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• 1997

An adenosine deaminase inhibitor-producing bacterium was isolated from soil. An isolate exhibiting high adenosine deaminase inhibitory activity, was designated J-89, and classified as a strain of Bacillus subtilis on the basis of its morphological, phenotypic characteristics, the menaquinone content and cellular fatty acid composition. To confirm the taxonomic position of the strain we need more information such as DNA-DNA homology and other chemotaxonomic characteristics. In this paper we provisionally named strain J-89 as Bacillus sp. J-89 pending further chemotaxonomic study and analysis of adenosine deaminase inhibitor.

• Journal of Microbiology
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• v.41 no.2
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• pp.83-88
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• 2003

The taxonomic position of actinomycete strain SCNU5$\^$T/, isolated from extensive foam in the aeration basin of an activated sludge process, was clarified by phenotypic, chemotaxonomic and phylogenetic analyses. The strain possesses wall chemotype IV, MK-9(H$\^$0/), as the major menaquinone, and contains saturated, monounsaturated and 10-methyl branched fatty acids. The G+C content of its DNA is 68.1 mol%. Phenotypic data and DNA relatedness to known species indicate that the strain SCNU5$\^$T/ represents a new species within the genus Tsukamurella, for which we propose the name Tsukamurella sunchonensis SP. NOV. The type Strain Of T. sunchonensis is SCNU5$\^$T/ (=KCTC 9827$\^$T/).

• Journal of Plant Biology
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• v.25 no.1
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• pp.9-19
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• 1982

A thin-layer chromatographic study was made of the chloroform-soluble and flavonoid fractions from the fruit peels of 16 species, 2 varieties and 5 formas of the Citrus plants cultivated in Je Ju Island for their interspecific relatinships. In addition, 3 hybrids and 9 native plants were also studied for their taxonomic position. Three phenograms were developed from these chromatographic data after cluster analysis via the unweighted paired group method using rithmatic average by Sneath and Sokal. These plants were grouped into 5 alliences based on the phenogram obtained from the chloroform-soluble fracitons, which were nearly identical to the subgenus rank by Tanaka, and rutinoside and neohesperidoside groups by Horowitz. Those from the flavonoid and methanol-soluble fractions were not able to evaluate the morphological classification except for a few cases.

• Animal Systematics, Evolution and Diversity
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• v.18 no.1
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• pp.91-98
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• 2002

Two marine tardigrades belonging to the genus Halechiniscus Richters, H. jejuensis n. sp. and H. remanei Schulz are recorded from Jeju Island, Korea. Halechiniscus jejuensis n. sp. is distinguished from the congeners by the shape and position of lateral body processes, the shape of sensory papilla on leg IV, and the contour of head portion not clearly divided into two lobes. A revised key to the nine species of the genus Halechiniscus is prepared.