• 제목/요약/키워드: Korea Polar Research Institute

검색결과 1,655건 처리시간 0.109초

Crystal Structure and Comparative Sequence Analysis of GmhA from Colwellia psychrerythraea Strain 34H Provides Insight into Functional Similarity with DiaA

  • Do, Hackwon;Yun, Ji-Sook;Lee, Chang Woo;Choi, Young Jun;Kim, Hye-Yeon;Kim, Youn-Jung;Park, Hyun;Chang, Jeong Ho;Lee, Jun Hyuck
    • Molecules and Cells
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    • 제38권12호
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    • pp.1086-1095
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    • 2015
  • The psychrophilic organism Colwellia psychrerythraea strain 34H produces extracellular polysaccharide substances to tolerate cold environments. Sedoheptulose 7-phosphate isomerase (GmhA) is essential for producing $\small{D}$-glycero-$\small{D}$-mannoheptose 7-phosphate, a key mediator in the lipopolysaccharide biosynthetic pathway. We determined the crystal structure of GmhA from C. psychrerythraea strain 34H (CpsGmhA, UniProtKB code: Q47VU0) at a resolution of $2.8{\AA}$. The tetrameric structure is similar to that of homologous GmhA structures. Interestingly, one of the catalytic residues, glutamate, which has been reported to be critical for the activity of other homologous GmhA enzymes, is replaced by a glutamine residue in the CpsGmhA protein. We also found differences in the conformations of several other catalytic residues. Extensive structural and sequence analyses reveal that CpsGmhA shows high similarity to Escherichia coli DnaA initiatorassociating protein A (DiaA). Therefore, the CpsGmhA structure reported here may provide insight into the structural and functional correlations between GmhA and DiaA among specific microorganisms.

Heavy Metal Pollution Monitoring at King Sejong Station, King George Island, Antarctica

  • Ahn, In-Young;Choi, Hee-Seon;Kim, Ko-Woon
    • Ocean and Polar Research
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    • 제25권4호
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    • pp.645-652
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    • 2003
  • The coastal environment of King George Island is potentially subject to contamination by pollutants arising from station operations, such as emissions from fossil fuel burning, oil spills, waste disposal, etc. As a preparatory step to assess such impacts on the marine environment and living organisms of this island, two molluscan species (the bivalve Laternula elliptica and the gastropod Nacella concinna) were selected as biomonitors for metal pollution monitoring, and their baseline levels have been investigated for the past several years at King Sejong Station. In this review, variability of the baseline levels is discussed in relation to body size, tissue type, and sex. Natural elevations of some metals are also discussed with respect to the environmental characteristics of this region.

북극해 박테리아, Pseudomonas aeruginosa에서 분리된 퀴놀론 알칼로이드 (Quinolone Alkaloids from the Arctic Bacterium, Pseudomonas aeruginosa)

  • 윤의중;한세종;김일찬;임정한
    • 생약학회지
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    • 제49권2호
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    • pp.108-112
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    • 2018
  • Four quinolone alkaloids, 2-heptyl-4-quinolone (1), 2-nonyl-4-quinolone (2), 2-undecyl-4-quinolone (3), and 2-undecen-1'-yl-4-quinolone (4), together with two nitrogen derived benzoic acid derivatives, N-acetylanthranilic acid (5) and o-acetamidobenzamide (6) have been isolated from the Arctic bacterial strain, Pseudomonas aeruginosa. The structures of the compounds were determined by 1D and 2D NMR, and MS experiments, as well as by comparison of their data with published values. To the best of our knowledge, compounds 3-6 were isolated for the first time from P. aeruginosa.

KOMPSAT-2 Terminal for Polar Station (K2PS) Development by KARI

  • Koo, In-Hoi;Kang, Ji-Hoon;Bae, Hee-Jin;Ahn, Sang-Il
    • 대한원격탐사학회지
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    • 제24권5호
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    • pp.409-416
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    • 2008
  • Recently, KARI developed "KOMPSAT-2 Terminal for Polar Station" which is high performance system newly required for stimulating KOMPSAT-2 application. The KOMPSAT-2 Terminal for Polar Station consists of one receiving system and two processing systems. The receiving system has been installed at Svalbard Satellite Station located at Norwegian Svalbard island. and the two receiving systems have been installed at Kongsberg Satellite Service AS located at Tromso Norway and Spot Image SA located at Toulouse France respectively. In this paper overall items of KOMPSAT-2 Terminal for Polar Station, which includes requirements, designs and operation concepts, are to be addressed with the verification result on its performance.

Crystal Structure and Functional Characterization of a Xylose Isomerase (PbXI) from the Psychrophilic Soil Microorganism, Paenibacillus sp.

  • Park, Sun-Ha;Kwon, Sunghark;Lee, Chang Woo;Kim, Chang Min;Jeong, Chang Sook;Kim, Kyung-Jin;Hong, Jong Wook;Kim, Hak Jun;Park, Hyun Ho;Lee, Jun Hyuck
    • Journal of Microbiology and Biotechnology
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    • 제29권2호
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    • pp.244-255
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    • 2019
  • Xylose isomerase (XI; E.C. 5.3.1.5) catalyzes the isomerization of xylose to xylulose, which can be used to produce bioethanol through fermentation. Therefore, XI has recently gained attention as a key catalyst in the bioenergy industry. Here, we identified, purified, and characterized a XI (PbXI) from the psychrophilic soil microorganism, Paenibacillus sp. R4. Surprisingly, activity assay results showed that PbXI is not a cold-active enzyme, but displays optimal activity at $60^{\circ}C$. We solved the crystal structure of PbXI at $1.94-{\AA}$ resolution to investigate the origin of its thermostability. The PbXI structure shows a $({\beta}/{\alpha})_8$-barrel fold with tight tetrameric interactions and it has three divalent metal ions (CaI, CaII, and CaIII). Two metal ions (CaI and CaII) located in the active site are known to be involved in the enzymatic reaction. The third metal ion (CaIII), located near the ${\beta}4-{\alpha}6$ loop region, was newly identified and is thought to be important for the stability of PbXI. Compared with previously determined thermostable and mesophilic XI structures, the ${\beta}1-{\alpha}2$ loop structures near the substrate binding pocket of PbXI were remarkably different. Site-directed mutagenesis studies suggested that the flexible ${\beta}1-{\alpha}2$ loop region is essential for PbXI activity. Our findings provide valuable insights that can be applied in protein engineering to generate low-temperature purpose-specific XI enzymes.

영지버섯(Ganoderma lucidum)으로 부터 분리한 이차대사산물 및 이들의 항 염증 활성 (Secondary Metabolites Isolated from Ganoderma lucidum and Their Anti-inflammatory Activity)

  • 김혜지;구만형;이준혁;서승석;윤의중
    • 생약학회지
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    • 제50권3호
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    • pp.232-238
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    • 2019
  • Phytochemical study of Ganoderma lucidum (Polyporaceae) let to the isolation of five lanostane triterpenoid (1-5), along with two nitrogen derived phenolic compounds, N-phenylethylformamide (6) and N-acetylphenethylamine (7). The structures of the compounds were determined by 1D and 2D NMR, and MS experiments, as well as by comparison of their data with published values. Compounds 6 and 7 were isolated for the first time from the genus Ganoderma and this species. All the compounds were evaluated for cancer chemopreventive potential based on their ability to inhibit nitric oxide (NO) production induced by lipopolysaccharide (LPS) in mouse macrophage RAW 264.7 cells in vitro. Among the isolates, compounds 2 and 3 showed moderate inhibitory activity against NO production.

남극, 킹조지섬, 세종과학기지 연안에 우점하는 남극암치아속 어류 두 종의 길이와 무게의 관계 (Length and Weight Relationship for Two Dominant Antarctic Notothenioid Fishes Caught in the Coastal Water off King Sejong Station, King George Island, Antarctica)

  • 박현;김일찬;강승현;김보미;한동원;김진형
    • 한국어류학회지
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    • 제29권2호
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    • pp.146-150
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    • 2017
  • 남극 연안에 우점하는 남극암치아목과, 암치아목속 어류 두 종 (Notothenia coriiceps와 Notothenia rossii)의 전장과 무게의 관계를 조사하였다. 어류는 2017년 1월에 남극 킹조지섬에 위치한 세종과학기지 연안에서 낚시로 채집되었다. 총 30마리가 채집된 N. coriiceps의 평균 전장은 266.0 mm였고, 7마리가 채집된 N. rossii의 평균전장은 275.4 mm이었다. 평균 무게의 경우 N. coriiceps는 283.1 g이었고, N. rossii는 290 g이었다. 전장과 무게의 관계를 조사한 결과, 두 종 모두 양의 상대성장 값(b>3)을 보였다. 본 조사에서 얻은 남극 연안에 우점하는 두 종의 크기 자료는 남극 해양생물의 환경적응 기작과 생물학적 대사과정을 이해하기 위한 관련 생리 연구를 수행하는데 있어서, 좋은 기초자료로 활용될 수 있을 것으로 기대된다.