• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.48-48
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• 2002

Glutathione (GSH) is most prevalent reducing thiols in eukaryotic cells and known that participates in many cellular processes. It was found that total amount of glutathione and the ratio of reduced to oxidized glutathione during development of Dictyostelium discoideum increase at the initial stage of the aggregation of amoeba.(omitted)

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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• pp.43-43
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• 2001

In cells of the eukaryotic microorganism Dictyostelium discoideum, at least eight small, four-EF hand calcium-binding proteins respectively are expressed at specific stages during development. One of these proteins, calcium-binding protein 3 (CBP3), first appears just prior to cell aggregation and then maintains relatively constant levels throughout development.(omitted)

• 아시안잔디학회지
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• 제10권1호
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• pp.71-80
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• 1996

Fourteen dictyostelids(12 species of genus Dictyostelium. 2 species of genus Polysphonylium) oc-curred in Mt. Chiri Korea. Soils samples were collected from the nine sites. In the broadleaved-deciduous forests and conifers, common species of cellular slime molds are Dictyostelium mucoroides, and D. brefeldianum. Only two species are above 30 in importance value and above 50% in presence. Dominant species in the broadleaved-deciduous forests is D. mecoroides wheras in the conifer forests is D. brefeldianum which was not common until now in Korea, found in the low elevation either. In addition, Five cellular slime molds occured in the Miscanthus sinensis community: 4 species of genus Dictyostelium and 1 species of genus Polysphonylium. Dominant species is D. purpureum. Importance value is very high, 85. This Result is exceptively unusual. It dind't occur in the other sites. Correlation between the altitudes and the occurrence and distribution of dictyostelids was not accurate. Merely dominant species were different according to forest types and organic matter contents in soil. Cellular slime molds have different favorite forest types. And the growth and germination are dependent on the soil enviroryrnental conditions and soil quility. Key words:Dictyostelids, Mt. Chiri D. mecoroides, D. brefeldianum. D. purpureum. Soil quility, Favorite forest type, Soil environmental condition.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.55-55
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• 2004

• 아시안잔디학회지
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• 제10권2호
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• pp.117-124
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• 1996

One new cellular slime mold, Dicivostelium valenstemmun sp. n. Shim et Chang, is isolated from the fermentation layer of soils in the cool temperate forests of Surak mountain, Korea. This species has the sori and sorophore yellow-pigmented, and sparse or irregular branches. And it is characterized by tall and robust sorocarps, well-form basal disks, mucoroides-type aggregations and large spores. This species has sorophores gradually tapering from bases to tips, simple capi- tate sorophore tips and conical bases. When prostrates on the plates, it has sparsely clavate bases. Spores are considerably large, 6.8~9.9 x 3.4~5.1 $\mu$m(avg. 8.5 x 4.1 $\mu$m), L /W index l.84~2.43(avg. 2.07) without polar granules. Key words: Diccyostelium valeustemmum, Cool temperate forests, Surak mountain.

• 아시안잔디학회지
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• 제10권3호
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• pp.231-246
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• 1996

In order to elucidate the human impact on the distribution of cellular slime molds, samples were collected from 3 types of forest ; natural forests(Mt. Deogyu and Mt. Tsukuba), semi-natural forests(Seoul Great Zoo and Tama Zoo), artificial forests(Seoul National University and Tokyo Gakugei University) .The distribution of cellular slime molds in mountains was different from that of zoo and universities. In mountains, endemic species was occurred and species diversity was higher than in zoo and universities. In zoo and universities disturbed by human, Dictyostelium sphaerocephalum was occurred with higher importance value than in mountains. 6 species were selected to investigate the effect of temperature on froctification; Polysphondylium canlidum, D. delicatum. D. firmibasis, D. sphaerocephalum P. violaceum, D. purpureum. P. violaceum and D. purpureum had an optimum temperature for fructification around 25~3O˚C but the others around 22~23˚C. The degree of sensitivity to temperature was as follows; P. candidum >D. lelicatum > D. firmibasis > D. sphaerocephalum > P. violaceum > D. purpureum. Key words: Human impact, Cellular slime molds, Occurrence and distribution, fructification, Dictylostelium delicatum. Dictyostelium sphaerocephalum.

• Journal of Plant Biology
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• 제26권3호
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• pp.131-139
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• 1983

Temperature response of amoebae of thermotactic mutants have been investigated. Amoebae of the mutant strain HO 428 showed positive thermotaxs which is strong at lower temperaturs and drops sharply above the growth temperature of amoebae. The temperature response of HO 428 amoebae was not affected by the length of amoebae on the grdients. HO 596 amoebae seemed to have both positive and negative thermotactic responses shortly after food depletion. Longer exposure of these amoebae on the thermal gradients induced a stronger negative response at lower temperatures and an apparent positive response at higher temperatures. A similar changes could be observed in HO 1445 amoebae. Based on the steady positive thermotactic response by HO 428 amoebae and the mode of change in termperature response at higher temperatures, 24$^{\circ}C$ and $25^{\circ}C$, by HO 596 amoebae, a model for the temperature response of vegetative Dictyostelium discoideum amoebae, strain HL 50, has been proposed. The main features of the model are: a positive response at the thermal gradients with midpoint temperatures lower than the growth temperatures of amoebae and a negative response above it.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.60-60
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• 2003

GSH-dependent glutaredoxinl (Grxl) was characterized in Dictyostelium discoideum. After starvation, the mRNA levels of grx1 gene increased during aggregation, thereafter decreased up to tip formation and increased again during culmination. To investigate the function of Grxl, the protein was overexpressed in D. discoideum using actinl5 promoter, The phenotype analysis on Grxl-overexpressed cells showed the maintenance of slug stage for a long period and delayed culmination under dark condition. To corroborate these phenotype by the enzyme, the two mutant forms of Grxl (C21S and C24S) were overexpressed in D. discoideum. The phenotype of two mutant cells represented no slug formation and the early culmination on dark condition. These results indicate that Grxl might regulate the transition from slug to culminant in darkness.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.218.2-218
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• 2005

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.782-787
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• 2015

In this study, we developed an assay system for missense mutations in human phenylalanine hydroxylases (hPAHs). To demonstrate the reliability of the system, eight mutant proteins (F39L, K42I, L48S, I65T, R252Q, L255V, S349L, and R408W) were expressed in a mutant strain (pah^-) of Dictyostelium discoideum Ax2 disrupted in the indigenous gene encoding PAH. The transformed pah - cells grown in FM minimal medium were measured for growth rate and PAH activity to reveal a positive correlation between them. The protein level of hPAH was also determined by western blotting to show the impact of each mutation on protein stability and catalytic activity. The result was highly compatible with the previous ones obtained from other expression systems, suggesting that Dictyostelium is a dependable alternative to other expression systems. Furthermore, we found that both the protein level and activity of S349L and R408W, which were impaired severely in protein stability, were rescued in HL5 nutrient medium. Although the responsible component(s) remains unidentified, this unexpected finding showed an important advantage of our expression system for studying unstable proteins. As an economic and stable cell-based expression system, our development will contribute to mass-screening of pharmacological chaperones for missense PAH mutations as well as to the in-depth characterization of individual mutations.