• Korean Journal of Microbiology
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• v.31 no.4
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• pp.261-266
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• 1993

A new methyltrophic bacterium which utilizes methanol as a sole source of carbon and energy was isolated from soil. It was Gram-negative, nonmotile, nonspore-forming rod, and strictly aerobic bacterium. Catalase and oxidase activities were present. Nitrate was reduced to nitrite. Vitamins and other growth factors were not required. Generation time was 1.6 hr under the optimal condition. The isolate assimilated methanol via the ribulose mono-phosphate pathway (Enter-Doudoroff varient) and did not have .alpha.-ketoglutarate dehydrogenase. It assimilated ammonia through glutamate dehydrogenase. The guanine plus cytosine content of the DNA was 61.0 mol%. The celular fatty acid composition was primarily straight-chain saturated $C^{16 : 0}$ acids (palmitic acids) and unsaturated $C_{16 :1}$ acid (palmitoleic acids), and the isolate also contained two unidentified $C_{17}$ branched fatty acids. The major ubiquinone was Q-8, and Q-6 and Q-7 were present as minor components. Phosphatidylethanolamine and phosphatidylglycerol were predominantly present, and diphosphatidyglycerol was also detected. Based on the physiological and biochemical properties, the isolate was assigned to a novel species of the genus Methylobacillus, Methylobacillus methanolovorus sp. nov.

• Korean Journal of Ecology and Environment
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• v.35 no.2 s.98
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• pp.103-110
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• 2002

Seasonal changes of the phytoplankton community was investigated from July 2000 to April 2001 at the river bed lake, Jangjwa Lake in the Imjin River, which appeared to be the most natural condition. A total of phytoplankton were composed of 112 taxa, belonging to 5 divisions,83 species, 10 varieties,1 variety-form, 1 form and 17 unidentified species. Of those, the green algae and the diatoms were present during the investigation periods more frequently then the other taxa. The phytoplantton standing crops varied from $2,943{\times}10^3\;cells/l$ on April 2001 to $5,742{\times}10^3\;cells/l$ on January 2001. The phytoplankton standing crops had a continuous high value over $3,000{\times}10^3\;cells/l$ during the investigated periods and showed the highest value during winter period. The major dominant species were Aulacoseira granulata, Chlamydomonas nivalis v. kobayasii, Dinobryon sertularia, Mougeotia so. and Uroglenopsis americana. Among those, Chlamydomonas nivalis v. kobayasii was a major dominant species during winter period.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.283-292
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• 1998

The community dynamics and distribution of dinoflagellates and their cysts were monitored monthly from June 1996 to May 1997 at six stations in Masan-Chinhae Bay, one of the famous bays for red-tide occurrence in Korea. The dinoflagellate standing crops ranged from the minimum of 306 cells $ml^{-1}$ in February to the maximum of 37,959 cells $ml^{-1}$ in May. The species causing massive blooms were Prorocentrum micans Ehrenberg and Ceratium furca (Ehrenberg) Claparede & Lachmann in July, Gymnodinium sanguineum Hirasaka in October, Alexandrium tamarense (Lebour) Balech in April and Proroeentrum minimum (Pavillard) Schiller in May. Twenty-seven taxa of dinoflagellate cysts were isolated, including 20 identified species and 7 unidentified species. The mean cyst abundance ranged from the minimum of 556 cysts $cm^{-3}$ in June to the maximum of 5,727 cysts$cm^{-3}$ in February. The spatial pattern of cyst distribution showed the gradual increase in abundance from offshore to inshore stations. The cyst genera of Protoperidinium, Gymnodinium, Serippsiella, Gyrodinium and Alexandrium were abundant throughout the year. The vertical distribution of cysts showed the surface miximum at the 0-2cm layer and the sub-surface maximum at the 2-4cm layer. Total abundance of cysts showed the most significant relationships with water temperature, and some minor relationship with dissolved oxygen, salinity, pH, phosphate and total inorganic nitrogen of surface and bottom layer in the water column. The number of dinoflagellate species decreased, while the abundance of cysts increased 4.5 times as compared with the observation of 10 years prior to the present study at the same stations of Masan-Chinhae Bay.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.354-358
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• 2019

In order to evaluate the migration of fungi into doenjang from its materials, meju and solar salt, microbial communities were analyzed using pyrosequencing. Dominant fungi of meju were Botrytis spp. (57.94%) and Dothiorella samentorum (24.08%). Unidentified fungal species (37.53%), unassigned species (32.60%) and several fungal species of small portion were identified in solar salt. In doenjang, Candida versatilis were predominantly detected (92.62%). Non-halophilic mold were dominantly identified from meju (low-salt fermented soybean), while halophilic bacteria and archaea for solar salt and salt-tolerance fungi such as C. versatilis for doenjang (high-salt fermented soybean) were frequently detected. These results implied that most predominant fungal species might not be migrated from meju and/or solar salt into doenjang.

• Animal Systematics, Evolution and Diversity
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• v.34 no.3
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• pp.162-167
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• 2018

To confirm the genetic identification and phylogenetic relationships of unidentified 6 baleen whales by-caught from 2002 to 2016, a partial sequence of approximately 500 base pair (bp) of the mitochondrial DNA (mtDNA) control region was analyzed and compared to published sequence from Genbank. Our results indicated that the two individuals among 6 specimens are clustered with Omura's whale clade through phylogenetic analysis, which had only a single haplotype. Omura's whale was reclassified as a new species in 2003 and they had not been previously reported in Korean waters. This study firstly revealed existence of Omura's whale in Korean waters by molecular analysis based on mtDNA control region.

• Animal Systematics, Evolution and Diversity
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• v.20 no.2
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• pp.109-140
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• 2004

Seven new species of cope pods associated with marine invertebrates are described from the Great Barrier Reef, Australia. They are Panjakus bidentis from the scleractinian Pocillopora verrucosa (Ellis and Solander), Scyphuliger humesi, S. vicinus and S. placidus from the scleractinian Acropora squarrosa (Ehrenberg), Doridicola parapatulus from the nudibranch Glossodoris atromarginata (Cuvier), Ruhtra germinata from an unidentified alcyonacean coral, and Collocheres oribullatus from the crinoid Comanthina belli (Carpenter).

• BMB Reports
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• v.36 no.5
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• pp.508-513
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• 2003

The bacterium Bacillus thuringiensis produces toxin inclusions that are deleterious to target insect larvae. These toxins are believed to interact with a specific receptor protein(s) that is present on the gut epithelial cells of the larvae. In various insect species (in particular those belonging to the lepidopteran class), aminopeptidase N (APN) is one of the two receptor proteins that are considered to be involved in toxin-receptor interactions. However, in mosquitoes, the nature and identity of the receptor protein is unknown. Here, using RT-PCR, we identified two isoforms of the APN transcripts in the Aedes aegypti mosquito larval midgut. These results are congruent with a previous report of multiple isoforms of the APN gene expression in lepidopteran larvae. Which of the two isoforms (or other yet unidentified receptor proteins) is involved in the killing of mosquito larvae remains to be elucidated.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.405-408
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• 2010

Diversity of myxobacteria in five soil samples from Asansi and Uponeup in Korea was explored by means of polymerase chain reaction (PCR) using primers that specifically bind 16S rDNA of myxobacteria. DNA sequence analysis of 76 PCR fragments containing myxobacterial 16S rDNA revealed five putative novel myxobacterial genera whose 16S rDNA sequences shared <95% sequence identity with those of the type strains. This finding indicates the presence of many uncultured and unidentified myxobacterial species in Korean soil.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.05a
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• pp.24-24
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• 2004

This study was investigated to the seasonal variation of attached diatoms communities in the Hantan River in November 2001, February, Ma and August 2002. It was identified the total 107 taxa which were composed of 95 species, 11 varieties and 1 unidentified speCies. The standing crops ranged 298,5004,776,000cells${\cdot}cm^{-2}.$and showed marked irregularly seasonal variations. It was higher value at the lower station than the upper station in fall. But it was similar values from the upper to the lower station by the effect of typhoon in summer. Chlorophyll concentrations ranged $13.4~304.2{\mu}m{\cdot}cm^{-2}.$ Standing crops and chlorophyll showed similar trends during investigation. Low diversity index values probably indicated the effects of envi~onmental stresses(water temperature, flow and current velocity) other than organic pollution. An assessment of organic pollution using epilithic diatoms(DAlpo) was $\alpha$-oligosaprobic states at the upper and mid stations, and was $\alpha$-mesosaprobic states at the lower stations.

• 한국해양학회지
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• v.28 no.1
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• pp.69-71
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• 1993

Food items of the five species of marine cladocerans were reported to be largely confined to centric diatoms. Reexamination of the prey items, however, revealed that flagellar organisms were also well fed by cladocerans. This additional finding suggests that marine cladocerans might extend their food items to weakly motile flagellates e.g., Prorocentrum micans, Protoperidinium sp. and unidentified flagellates.