• Title/Summary/Keyword: {\beta}$

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Cooperation of $G{\beta}$ and $G_{\alpha}q$ Protein in Contractile Response of Cat Lower Esophageal Sphincter (LES)

  • Sohn, Uy-Dong;Lee, Tai-Sang
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.6
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    • pp.349-355
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    • 2003
  • We previously shown that LES contraction depends on $M_3$ receptors linked to PTX insensitive $G_q$ protein and activation of PLC. This results in production of $IP_3$, which mediates calcium release, and contraction through a CaM dependent pathway. In the esophagus ACh activates $M_2$ receptors linked to PTX sensitive $G_{i3}$ protein, resulting in activation of PLD, presumably, production of DAG. We investigated the role of PLC isozymes which can be activated by $G_q$ or $G{\beta}$ protein on ACh-induced contraction in LES and esophagus. Immunoblot analysis showed the presence of 3 types of PLC isozymes, $PLC-{\beta}1$, $PLC-{\beta}3$, and $PLC-{\gamma}1$, but not $PLC-{\beta}2$, $PLC-{\beta}4$, $PLC-{\gamma}2$, $PLC-{\delta}1$, and $PLC-{\delta}2$ from both LES and esophageal muscle. ACh produced contraction in a dose dependent manner in LES and esophageal muscle cells obtained by enzymatic digestion with collagenase. $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody incubation reduced contraction in response to ACh in LES but not in esophageal permeabilized cells, but $PLC-{\gamma}1$ antibody incubation did not have an inhibitory effect. The inhibition by $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody on Ach-induced contraction was antibody concentration dependent. The combination with $PLC-{\beta}_1$ and $PLC-{\beta}_3$ antibody completely abolished the contraction, suggesting that $PLC-{\beta}1$ and $PLC-{\beta}3$ have a synergism to inhibit the contraction in LES. $PLC-{\beta}1$, -${\beta}3$ or -${\gamma}1$ antibody did not reduce the contraction of LES cells in response to DAG ($10^{-6}$ M), suggesting that this isozyme of PLC may not activate PKC. When $G_{q/11}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}3$, but not of PLC ${\beta}_1$ was additive (Fig. 6). In contrast, when $G_{\beta}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}_1$, but not of PLC ${\beta}_3$ was additive. This data suggest that $G_{q/11}$/11 or $G{\beta}$ may activate cooperatively different PLC isozyme, $PLC{\beta}_1$ or $PLC{\beta}_3$ respectively.

${\beta}-Glucans$ in Barley and Oats and Their Changes in Solubility by Processing (보리와 귀리의 ${\beta}-Glucans$ 및 가공에 의한 용해성의 변화)

  • Lee, Young-Tack
    • Applied Biological Chemistry
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    • v.39 no.6
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    • pp.482-487
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    • 1996
  • Five barley and two oat varieties grown in Korea were investigated for soluble, insoluble, and total $(1{\to}3)$, $(1{\to}4)-{\beta}-D-glucans$. Total and insoluble ${\beta}-glucans$ after extraction of soluble ${\beta}-glucans$ with water were analyzed, and the soluble ${\beta}-glucans$ were calculated as the difference between total and insoluble ${\beta}-glucans$. The total ${\beta}-glucans$ in whole barleys were in a range of $3.3{\sim}5.6%$(average 4.4%), and those in pearled barleys were In a range of $3.3{\sim}7.1%$(average 5.2%). In whole barleys, on average, 54% of the ${\beta}-glucans$ was soluble and in pearled barley 46%. Whole oats contained $3.1{\sim}4.0%$ total ${\beta}-glucans$, and dehulling increased the groat ${\beta}-glucans$ contents to $4.0{\sim}4.8%$. Oats demonstrated considerably higher ${\beta}-glucans$ solubility of 84% than barley. ${\beta}-Glucans$ in barley and oats were rapidly extracted at the beginning of the extraction and almost all of the ${\beta}-glucans$ were extracted after $2{\sim}3 hr extraction. As extraction temperature increased from $23^{\circ}C$ to $45^{\circ}C$, more soluble ${\beta}-glucans$ were extracted. However, solubility of barley ${\beta}-glucans$ decreased at a relatively high temperature of $65^{\circ}C$. Steam-cooking reduced the analytical solubility of barley and oat ${\beta}-glucans$, while roasting seemed to render the ${\beta}-glucans$ of barley more soluble.

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Characterization of the \beta-Galactosidase Produced by Streptomyces sp. YB-10 (\beta-Galactosidase를 생산하는 Streptomyces sp. YB-10의 분리 및 효소 특성)

  • 윤기홍;이경섭;김창진
    • Microbiology and Biotechnology Letters
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    • v.31 no.2
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    • pp.151-156
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    • 2003
  • A strain YB-10 was isolated from soil as a producer of the extracellular $\beta$-D-galactosidase, which catalyzes the hydrolysis of lactose. The strain YB-10 was identified as Streptomyces sp. on the basis of its cultural, morphological and physiological properties. After treating culture supernatant of the isolate with ammonium sulfate, the precipitated protein was used as a crude $\beta$-galactosidase for analyzing its reaction properties with para-nitrophenyl-$\beta$-D-galactosidase(pNP-$\beta$Gal) as a substrate. The $\beta$-galactosidase showed its maximal activity at pH 6.0 and 6$0^{\circ}C$. The enzyme was also active on lactose. The hydrolyzing activity of $\beta$-galactosldase for pNP-$\beta$Gal and lactose was decreased by galactose. Its hydrolyzing activity far lactose was also decreased by glucose, but the activity for pNP-$\beta$Gal was increased to 1.8-folds by glucose.

Quality Characteristics of Barley ${\beta}$-Glucan Enriched Noodles (보리 ${\beta}$-glucan 강화 국수의 품질 특성)

  • Lee, Young-Tack;Jung, Ji-Young
    • Korean Journal of Food Science and Technology
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    • v.35 no.3
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    • pp.405-409
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    • 2003
  • This study was conducted to evaluate quality characteristics of noodles containing barley flour and ${\beta}$-glucan enriched fraction. Compared to 100% wheat flour, composite flours containing barley flour and ${\beta}$-glucan enriched fraction decreased initial pasting temperature and increased maximum peak viscosity. The noodles containing ${\beta}$-glucan enriched fraction exhibited somewhat darker color and lower values in cooked weight, volume, moisture content, and cooking loss. From the textural properties measured by texture analyzer, the noodles with 30% barley flour and ${\beta}$-glucan enriched fraction were similar to 100% wheat noodle in springiness value and significantly higher in gumminess, hardness, and chewiness. The results of sensory evaluation indicated that barley flour or ${\beta}$-glucan enriched fraction at levels up to 30% could be substituted for wheat flour without seriously depressing noodle quality. Cooking of raw noodle with ${\beta}$-glucan enrichment slightly increased total, insoluble, and soluble ${\beta}$-glucan content.

Suppression of the Wnt/${\beta}$-catenin Pathway by Bryostatin-1 (Bryostatin-1에 의한 Wnt/${\beta}$-Catenin 신호전달체계 저해효과)

  • Park, Seoyoung;Oh, Sangtaek
    • Microbiology and Biotechnology Letters
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    • v.42 no.1
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    • pp.89-92
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    • 2014
  • The Wnt/${\beta}$-catenin pathway plays important roles in a variety of biological processes, such as cell proliferation, differentiation, and organ development. Here, we used a cell-based reporter assay to identify bryostatin-1, a natural macrocyclic lactone, as an inhibitor of the Wnt/${\beta}$-catenin pathway. Bryostatin-1 suppressed ${\beta}$-catenin response transcription (CRT), which was activated by a Wnt3a-conditioned medium (Wnt3a-CM), through a decrease in the intracellular ${\beta}$-catenin protein levels, without affecting its mRNA level. In addition, pharmacological inhibition of proteasome abrogated bryostatin-1-mediated down-regulation of the ${\beta}$-catenin protein level. Our findings suggest that bryostatin-1 attenuates the Wnt/${\beta}$-catenin pathway through the promotion of proteasomal degradation of ${\beta}$-catenin.

Four New Acetylated Ginsenosides from Processed Ginseng(Sun Ginseng)

  • Park, Il-Ho;Han, Sang-Beom;Kim, Jong-Moon;Piao, Longzhu;Kwon, Sung-Won;Kim, Na-Young;Kang, Tak-Lim;Park, Man-Ki;Park, Jeong-Hill
    • Archives of Pharmacal Research
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    • v.25 no.6
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    • pp.837-841
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    • 2002
  • Four new acetylated ginsenosides were isolated from the processed ginseng (SG, sun ginseng). Their structures were determined to be $3{\beta},{\;}12{\beta}-dihydroxydammar-20(22),24-diene-3-O-{\beta}-D-glucopyranosyl(1{\rightarrow}2)-{\beta}-D-6"-O-acetylglucopyranoside;{\;}3{\beta},12{\beta}-dihydroxydammar-20(21),{\;}24-diene-3-O-{\beta}-D-glucopyranosyl(1{\rightarrow}2)-{\beta}-D-6"-O-acetylglucopyranoside;{\;}3{\beta},{\;}6{\alpha},12{\beta}-trihydroxydammar-20(22),24-diene-6-O-{\beta}-D-6'-O-acetylglucopyranoside{\;}and{\;}3{\beta},6{\alpha},12{\beta}-trihydroxydammar-20(21),24-diene-6-O-{\beta}-D-6'-O-acetylglucopyranoside$ based on spectroscopic evidences. The compounds were named ginsenoside $Rs_4,{\;}Rs_5,{\;}RS_6{\;}and{\;}Rs_7$, respectively.pectively.

Synthesis and Physical Properties of Biocompatible and Biodegradable Chitin Derivatives Vl. -Biodegradation of $\beta$-Chitin and Its Derivatives by Lysozyme- (생체적합성과 생분해성을 갖는 키틴유도체의 합성과 물성 VI. -$\beta$-키틴과 그 유도체들의 라이소자임에 의한 생분해도 및 물성변화-)

  • 김선정;이영무
    • Journal of Biomedical Engineering Research
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    • v.16 no.3
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    • pp.257-264
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    • 1995
  • The $\beta$-chitin derivatives were synthesized by reacting $\beta$-chitin with chloropropane, propyleneoxide and chloropropane diol to form propyl chitin (PPC), hydroxypropyl chitin (HPC) and dihydroxypropyl chitin (DHPC), respectively. Cast films from $\beta$-chitin and $\beta$-chitin derivatives solutions degraded by Iyrozyme in pseudo-extrra cellular fluid (PECF) solutions, at pH1.2, pH6.7 and pH8.2. Chitin derivatives rapidly degraded compared with virgin $\beta$-chitin within the first week. DHPC showed the best biodegradation among these derivatives.

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Simultaneous Expression of Pseudomonas sp. Endo-1,4$\beta$-Glucanase and $\beta$-1,4=Glucisidase Gene in Escherichia coli and Saccharomyces cerevisiae (Pseudomonas sp. Endo-1,4-$\beta$-Glucanase와 $\beta$-1,4-Glucosidase 유전자의 대장균 및 효모에서의 동시 발현)

  • Kim, Yang-Woo;Chun, Sung-Sik;Chung, Young-Chul;Sung, Nack-Kie
    • Microbiology and Biotechnology Letters
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    • v.23 no.6
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    • pp.652-658
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    • 1995
  • We attempted simultaneous expression of genes coding for endoglucanase and $\beta $-glucosidase from Pseudomonas sp. by using a synthetic two-cistron svstem in Escherichia coli and Saccharomyces cerevisiae. Two-cistron system, 5'--tac promoter-endoglucanase gene--$\beta $-glucosidase gene-- 3', 5'-tac promoter--$\beta $-glucosidase gene--endoglucanase gene--3' and 5'-tac promoter--endoglucanase gene--SD sequence--$\beta $-glucosidase gene--3, were constructed, and expressed in E. coli and S. cerevisiae. The E. coli and S. cerevisiae contained two-cistron system produced simultaneously endoglucanase and $\beta $-glucosidase. The recombinant genes contained the bacterial signal peptide sequence produced low level of endoglucanase and $\beta $-glucosidase in S. cerevisiae transformants: Approximately above 44% of two enzymes was localized in the intracellular fraction. The production of endoglucanase and $\beta $-glucosidase in veast was not repressed in the presence of glucose or cellobiose. The veast strain contained recombinant DNA with two genes hydrolyzed carboxvmethyl cellulose, and these endoglucanase and $\beta $-glucosidase degraded CMC synergistically to glucose, cellobiose and oligosaccharide. This result suggests the possibility of the direct bioconversion of cellulose to ethanol by the recombinant yeast.

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Prediabetic In vitro Model in Pancreatic Beta Cells Induced by Interleukin-$1{\beta}$ (췌장 베타세포에서 인터루킨-$1{\beta}$로 유도한 인슐린 의존형 당뇨병 실험 모델)

  • Lee, Ihn-Soon;Lee, In-Ja;Kim, Kyong-Tai
    • YAKHAK HOEJI
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    • v.42 no.4
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    • pp.408-413
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    • 1998
  • To establish prediabetes in vitro/ model concerning the etiology of Insulin Dependent Diabetes Mellitus (IDDM) in cellular level we have designed experimental prediabefic model in pancreatic beta cells. RINm5F, HIT-T15 and isolated rat islets were chosen as pancreatic beta cells. Since interleukin-$1{\beta}$-induced beta cell cytotoxicity has been implicated in the autoimmune cytotoxicity of IDDM, we used inteleukin-$1{\beta}$ as diabetogenic agent. For establishment of prediabetic in vitro model, the degree of beta cell deterioration was determined by cell proliferation, insulin release and morphological appearance. Cell proliferation, insulin release and morphology were changed dose-dependently in condition that inteleuldn-$1{\beta}$ was exposured to pancreatic beta cells. The concentration and exposure time of interleukin-$1{\beta}$ to set up prediabetic model in beta cell lines and isolated rat islets were 100${\sim}$1000U/ml, 48hr. And 25${\sim}$100U/ml, 48hr, respectively.

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Production and bioactivity of recombinant tilapia IL-$1\beta$

  • Hong, Su-Hee
    • Journal of fish pathology
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    • v.22 no.2
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    • pp.147-153
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    • 2009
  • To study the biological activity of interleukin-$1\beta$(IL-$1\beta$), a proinflammatory cytokine, in nile tilapia, Oreochromis niliticus, the recombinant tilapia IL-$1\beta$ was produced in E. coli cells based on pQE vector. Ni-NTA (nitriloacetic acid) metal affinity chromatography was used to purify recombinant protein. The eluted fractions exhibited a single band of protein with a molecular weight of about 25kDa, which is in close agreement with 25.4 kDa predicted by the cDNA sequence. The biological activity of the purified recombinant tilapia IL-$1\beta$ was tested through its effects on IL-$1\beta$ gene expression, which are known as IL-$1\beta$ inducible genes in mammals and fishes. IL-$1\beta$ gene expression induced by poly I:C, a synthetic double stranded RNA, was also assessed in tilapia head kidney cells. IL-$1\beta$ gene expression was analysed using QPCR (quantitative polymerase chain reaction). The ratio of the indicated gene expression was expressed as the relative mRNA level to $\beta$-actin mRNA level, which is constitutively expressed in macrophages. Consequently, head kidney cells incubated for three hours with rIL-$1\beta$(10, 2, 1 $\mu{g}$/ml) showed a dose dependent increase in IL-$1\beta$ mRNA levels and 1 $\mu{g}$/ml of poly I:C was also able to induce IL-$1\beta$ gene expression in head kidney in tilapia.