• Title/Summary/Keyword: $G{\beta}$

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Bacillus sp. WS-42에 의한$\beta$-Mannanase 생산배지의 최적화

  • Kim, Jong-Hwa;Lee, Tae-Kyoo;Yang, Hee-Cheon;Oh, Deok-Kun
    • Microbiology and Biotechnology Letters
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    • v.25 no.2
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    • pp.212-217
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    • 1997
  • A strain of Bacillus sp. WS-14 was isolated from soil. Medium optimization for ${\beta}-mannanase$ production by Bacillus sp. WS-14 was performed. Effect of various carbon sources on ${\beta}-mannanase$ production was investigated and locust bean gum was the most effective for ${\beta}-mannanase$ production. ${\beta}-mannanase$ activity and cell growth increased with increasing the concentration of locust bean gum, however, the amounts were not significant. Among nitrogen sources, soytone was the most effective for ${\beta}-mannanase$ production. Inorganic compounds such as $KH_2PO_4,\;NaCl\;Na_2CO_3\;and\;MgSO_4{\cdot}7H_2O\;on\;{\beta}-mannanase$ production were optimized for ${\beta}-mannanase$ production. Locust bean gum of 10.0 g/l, soytone of 5.0 g/l, $KH_2PO_4$ of 2.0 g/l, NaCl of 10.0 g/l, $MgSO_4{\cdot}7H_2O\;of\;0.2\;g/l,\;Na_2CO_3$, of 2.0 g/l were selected as optimum content. Production of ${\beta}-mannanase$ by using the optimum medium was carried out. The maximum ${\beta}-mannanase$ activity of 20.8 unit/ml could be obtained after 14 h fermentation which corresponed to the productivity of ${\beta}-mannanase$ of 1.48 unit/ml-h.

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Beta-amyloid peptide degradation by aminopeptidase and its functional role in Alzheimer's disease pathogenesis

  • AhnJo, Sang-Mee
    • 한국약용작물학회:학술대회논문집
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    • 2006.04a
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    • pp.75-90
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    • 2006
  • Both synthetic and endogenous $A{\beta}$ are degraded by peptidase G. Both $A{\beta}40$ and 42 are cleaved by peptidase G. Peptidase G cleaves $A{\beta}40$ into small fragments ($A{\beta}18$) which lacks aggregation property and are not toxic to neuron. Peptidase G seems to degrade multimeric $A{\beta}$ more efficiently than monomeric $A{\beta}$. Peptidase G protects neurons from toxicity induced by $A{\beta}$ by cleaving it into smaller fragments. Thus, dis-regulation of peptidase G could contribute amyloid deposit found in AD brain.

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Variation of β-carotene Concentration in Soybean Seed and Sprout

  • Kang, Eun-Young;Kim, Eun-Hye;Chung, Ill-Min;Ahn, Joung-Kuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.4
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    • pp.324-330
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    • 2012
  • In this study, ${\beta}$-carotene concentrations was determined in soybean cultivar according to seed size, usage, seed coat color and cotyledon color as well as the process of seed germination. The total average concentration of ${\beta}$-carotene was $6.6{\mu}g/g$ in soybean seed, $33.3{\mu}g/g$ in soybean sprout. According to seed size, the total ${\beta}$-carotene concentration of soybean was $6.9{\mu}g/g$ in large soybean seed, $6.7{\mu}g/g$ in medium soybean seed, and $6.31{\mu}g/g$ in small soybean seed. In soybean sprout, the total ${\beta}$-carotene concentration was $21.4{\mu}g/g$ in large soybean sprout, $30.5{\mu}g/g$ in medium soybean sprout, and $43.5{\mu}g/g$ in small soybean sprout. According to the utilization of seed, the total ${\beta}$-carotene concentration of soybean seed was $7.2{\mu}g/g$ in cooked with rice soybean seed, $6.1{\mu}g/g$ in paste and curd soybean seed, and $6.3{\mu}g/g$ in sprout soybean seed. In soybean sprout, the total ${\beta}$-carotene concentration was $25.9{\mu}g/g$ in cooked with rice soybean sprout, $32.4{\mu}g/g$ in paste and curd soybean sprout, and $41.9{\mu}g/g$ in sprout soybean sprout. When comparison with seed coat color, the total ${\beta}$-carotene concentration of soybean with brown seed coat ($8.8{\mu}g/g$) was slightly higher than those of soybean with yellow ($6.1{\mu}g/g$). In soybean sprout, the total ${\beta}$-carotene concentration was $21.8{\mu}g/g$ in black seed coat sprout, $38.7{\mu}g/g$ in brown seed coat sprout, $34.1{\mu}g/g$ in green seed coat sprout, $39.5{\mu}g/g$ in yellow seed coat sprout, and $30.5{\mu}g/g$ in mottle seed coat sprout. The results of this study suggested the functional characteristics of soybean through quantitative analysis of ${\beta}$-carotene.

MINIMAL CLOZ-COVERS AND BOOLEAN ALGEBRAS

  • Kim, ChangIl
    • Korean Journal of Mathematics
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    • v.20 no.4
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    • pp.517-524
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    • 2012
  • In this paper, we first show that for any space X, there is a Boolean subalgebra $\mathcal{G}(z_X)$ of R(X) containg $\mathcal{G}(X)$. Let X be a strongly zero-dimensional space such that $z_{\beta}^{-1}(X)$ is the minimal cloz-coevr of X, where ($E_{cc}({\beta}X)$, $z_{\beta}$) is the minimal cloz-cover of ${\beta}X$. We show that the minimal cloz-cover $E_{cc}(X)$ of X is a subspace of the Stone space $S(\mathcal{G}(z_X))$ of $\mathcal{G}(z_X)$ and that $E_{cc}(X)$ is a strongly zero-dimensional space if and only if ${\beta}E_{cc}(X)$ and $S(\mathcal{G}(z_X))$ are homeomorphic. Using these, we show that $E_{cc}(X)$ is a strongly zero-dimensional space and $\mathcal{G}(z_X)=\mathcal{G}(X)$ if and only if ${\beta}E_{cc}(X)=E_{cc}({\beta}X)$.

Molecular Signature That Determines the Acute Tolerance of G Protein-Coupled Receptors

  • Min, Chengchun;Zhang, Xiaohan;Zheng, Mei;Sun, Ningning;Acharya, Srijan;Zhang, Xiaowei;Kim, Kyeong-Man
    • Biomolecules & Therapeutics
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    • v.25 no.3
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    • pp.239-248
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    • 2017
  • Desensitization and acute tolerance are terms used to describe the attenuation of receptor responsiveness by prolonged or intermittent exposure to an agonist. Unlike desensitization of G protein-coupled receptors (GPCRs), which is commonly explained by steric hindrance caused by the ${\beta}$-arrestins that are translocated to the activated receptors, molecular mechanisms involved in the acute tolerance of GPCRs remain unclear. Our studies with several GPCRs and related mutants showed that the acute tolerance of GPCRs could occur independently of agonist-induced ${\beta}$-arrestin translocation. A series of co-immunoprecipitation experiments revealed a correlation between receptor tolerance and interactions among receptors, ${\beta}$-arrestin2, and $G{\beta}{\gamma}$. $G{\beta}{\gamma}$ displayed a stable interaction with receptors and ${\beta}$-arrestin2 in cells expressing GPCRs that were prone to undergo tolerance compared to the GPCRs that were resistant to acute tolerance. Strengthening the interaction between $G{\beta}{\gamma}$ and ${\beta}$-arrestin rendered the GPCRs to acquire the tendency of acute tolerance. Overall, stable interaction between the receptor and $G{\beta}{\gamma}$ complex is required for the formation of a complex with ${\beta}$-arrestin, and determines the potential of a particular GPCR to undergo acute tolerance. Rather than turning off the signal, ${\beta}$-arrestins seem to contribute on continuous signaling when they are in the context of complex with receptor and $G{\beta}{\gamma}$.

Quanrum Ballistic Transport in a Two-Dimensional Electron Gas (2차원 전자개스에서 양자 탄동적 수송현상)

  • 최점수;정문성
    • Journal of the Korean Vacuum Society
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    • v.4 no.2
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    • pp.224-229
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    • 1995
  • 쌍곡선 모델을 사용하여 미시 통로죔을 통과하는 2차원 전자들의 양자 탄동적 수송현상을 연구하였다. 통로죔은 타원좌표계($\alpha$, $\beta$)에서 $\beta$=$\beta$o, $\pi$-$\beta$o로 주어지는 두 쌍곡선으로 기술하였다. 양자화된 88컨덕턴스 G는 타원좌표계에서 주어진 슈뢰딩거 방정식과 쌍곡선 경계조건을 만족하는 짝 매튜 함수를 이용하여 계산하였다. 그 결과는 채널수 Nc는 통로죔 폭 W뿐만 아니라 곡률 관련좌표 $\beta$o에 의존함을 나타내었다. 또한 곡률에 의존하는 터널링도 양자화된 G의 그래프의 모양을 나타내는 중요한 요소임을 나타내 주었다. 고정된 통로폭에서 Nc가 일정한 $\beta$o영역에서는 $\beta$o의 연속적 변화에 G는 연속적으로 변화하였지만 $\beta$o가 크게 변화할 때는 Nc가 변화하여 G는 불연속적으로 변화하였다. 만일 터널링이 거의 허용이 안되는 $\beta$o의 영역에서는 G는 계단식의 변화만 보여주었다.

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Effects of Dietary ${\beta}-1,3$ Glucan on Growth and Immune Responses in Juvenile Olive Flounder, Paralichthys olivaceus (치어기 넙치 사료내 ${\beta}-1,3$ 글루칸의 첨가가 성장 및 비특이적 면역반응에 미치는 영향)

  • Kim, Young-Chul;Kim, Kang-Woong;Lee, Seung-Hyung;Park, Gun-Jun;Okorie, Okorie Eme;Kang, Yong-Jin;Bai, Sung-Chul C.
    • Journal of Aquaculture
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    • v.19 no.4
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    • pp.247-253
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    • 2006
  • This study was conducted to investigate the effects of dietary supplementation of ${\beta}-1,3$ glucan on growth and immune responses in juvenile olive flounder, Paralichthys olivaceus fed the white fish meal based diets for 6 weeks. Five experimental diets supplemented with ${\beta}-1,3$ glucan at 0, 0.01, 0.025, 0.05, 0.1 % (Control, $G_{0.01},\;G_{0.025},\;G_{0.05}\;and\;G_{0.1}$, respectively) of diet on a dry-matter basis. Five experimental diets were formulated to be isonitrogenous and isocaloric to contain 50.0% crude protein and 16.7 kJ available energy $g^{-1}$. Fish averaging $3.2{\pm}0.1\;g\;(mean{\pm}SD)$ were randomly distributed in each aquarium as triplicate groups of 15 fish. Weight gain (WG, %), specific growth rate (SGR, %), and feed efficiency (FE, %) of fish fed $G_{0.1}$ diet were found significantly higher than those of fish fed Control, $G_{0.01},\;G_{0.025}\;and\;G_{0.05}$ diets (P<0.05). However, there was no significant difference among the fish fed control, $G_{0.01},\;G_{0.025}$. Chemiluminescent responses (CL) of fish fed $G_{0.1}$ diet were significantly higher than those of fish fed the other diets. Serum lysozyme activities of fish fed $G_{0.05}$ and $G_{0.1}$ diets were higher than those of fish fed control, $G_{0.025}$ and $G_{0.05}$ diets. Fish fed $G_{0.1}$ diet showed a significantly lower cumulative mortality than did fish fed control diet throughout the challenge test (P<0.05). These results suggested that based on growth rate, feed efficiency, non-specific immunity and protection against microbial infections the optimum dietary ${\beta}-1,3$ gulcan could be greater than 0.05% but less than 1.0% in juvenile olive flounder, Paralichthys oilvaceus.

Phosphatidylinositol 3-kinase functionally compartmentalizes the concurrent $G_s$ signaling during $\beta_2$-adrenergic stimulation

  • Jo, Su-Hyun
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.29-29
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    • 2003
  • Compartmentation of intracellular signaling pathways serves as an important mechanism conferring the specificity of G protein-coupled receptor (GPCR) signaling. In the heart, stimulation of $\beta$$_2$-adrenoceptor ($\beta$$_2$-AR), a prototypical GPCR, activates a tightly localized protein kinase A (PKA) signaling, which regulates substrates at cell surface membranes, bypassing cytosolic target proteins (eg, phospholamban). Although a concurrent activation of $\beta$$_2$-AR-coupled $G_{i}$ proteins has been implicated in the functional compartmentation of PKA signaling, the exact mechanism underlying the restriction of the $\beta$$_2$-AR-PKA pathway remains unclear. In the present study, we demonstrate that phosphatidylinositol 3-kinase (PI3K) plays an essential role in confining the $\beta$$_2$-AR-PKA signaling. Inhibition of PI3K with LY294002 or wortmannin enables $\beta$$_2$-AR-PKA signaling to reach intracellular substrates, as manifested by a robust increase in phosphorylation of phospholamban, and markedly enhances the receptor-mediated positive contractile and relaxant responses in cardiac myocytes. These potentiating effects of PI3K inhibitors are not accompanied by an increase in $\beta$$_2$-AR-induced cAMP formation. Blocking $G_{i}$ or $G_{$\square$$\square$}$ signaling with pertussis toxin or $\beta$ARK-ct, a peptide inhibitor of $G_{$\square$$\square$}$, completely prevents the potentiating effects induced by PI3K inhibition, indicating that the pathway responsible for the functional compartmentation of $\beta$$_2$-AR-PKA siglaling sequentially involves $G_{i}$, $G_{$\square$$\square$}$, and PI3K. Thus, PI3K constitutes a key downstream event of $\beta$$_2$-AR- $G_{i}$ signaling, which confines and negates the concurrent $\beta$$_2$-AR/Gs-mediated PKA signaling.gnaling.

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Effect of $Glucanex^{(R)}$ 200G on Yeast Cell Wall (효모의 세포벽에 대한 $Glucanex^{(R)}$ 200G의 영향)

  • 김광석;장정은;윤현식
    • KSBB Journal
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    • v.19 no.4
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    • pp.288-290
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    • 2004
  • The cell wall of fifteen yeast strains were treated with Glucanex$^{(R)}$ 200G that contained mainly ${\beta}$1,3-glucanase and some ${\beta}$1,6-glucanase. In our previous study it was found that the yeasts that are more resistant to Glucanex$^{(R)}$ 200G treatment contained more ${\beta}$-glucan than the yeasts that are less resistant to Glucanex$^{(R)}$200G treatment. By measuring the resistance of cell wall to Glucanex$^{(R)}$ 200G, the relative content of ${\beta}$-glucan in yeast cell wall could be estimated. The resistance of cell wall to Glucanex$^{(R)}$ 200G was measured by counting viable cell number after reaction with and without Glucanex$^{(R)}$200G. The resistance of fifteen yeast strains to Glucanex$^{(R)}$ 200G were presented.ere presented.

β-G-BICONTINUOUS, β-G-COMPACTNESS AND β-G-STABLE IN DITOPOLOGICAL TEXTURE SPACES

  • Ibrahim, Hariwan Z.
    • The Pure and Applied Mathematics
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    • v.26 no.1
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    • pp.35-47
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    • 2019
  • The purpose of this paper is to introduce and study new notions of continuity, compactness and stability in ditopological texture spaces based on the notions of ${\beta}$-g-open and ${\beta}$-g-closed sets and some of their characterizations are obtained. Finally, the relationships between these concepts and the other related concepts are investigated.