• Journal of Life Science
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• v.18 no.4
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• pp.461-466
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• 2008

Transforming growth $factor-{\beta}$ ($TGF-{\beta}$)-dependent apoptosis is important in the elimination of damaged or abnormal cells from normal tissues in vivo. Gadd45b has been known to participate in $TGF-{\beta}-induced$ apoptosis by the activation of p38 kinase. In this report, we show that Gadd45b is an immediate-early response gene for $TGF-{\beta}$ during apoptosis in EpH4 cells. To elucidate the molecular mechanism of $TGF-{\beta}-induced$ Gadd45b gene expression, we cloned the 5'-flanking region of the mouse Gadd45b gene. When transfected into EpH4 cells, this 5'-flanking region conferred promoter activity and inducibility by $TGF-{\beta}$. Deletion analyses demonstrated that the minimal promoter activity was detected in the proximal region 220 bp upstream of the transcription initiation site. We also found that the proximal Gadd45b promoter is activated by $TGF-{\beta}$ through the action of Smad2, Smad3, and Smad4. Finally, we show that the expression of Gadd45b gene by $TGF-{\beta}$ is suppressed in EpRas cells in which $TGF-{\beta}$ could not induce apoptosis, suggesting that Gadd45b may be a crucial target for $TGF-{\beta}-induced$ apoptosis in EpH4 cells.

• Journal of Life Science
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• v.10 no.3
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• pp.307-316
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• 2000

Bacillus circulans S-1 extracellular pullulan 6-glucanohydrolase (EP) (EC 3.2.1.41) has been characterized with a purified enzyme of 140 kDa. The N-terminal amino acid sequence of the purified enzyme was P-L-N-M-S-Q-P. The enzyme displayed a temperature optimum of around $60^{\circ}C$ and a pH optimum of around pH 9.0. The enzyme was stable to incubation from pH 4.0 to pH 11.0 at $4^{\circ}C$ for 48h. The presence of substrate allowed the protection of the enzyme from heat inactivation. The activity of the enzyme was stimulated by several metal ions such as Mn2+ and Ca2+. The enzyme had an apparent Km of 7.92 mg/ml for pullulan. The purfied enzyme completely hydrolysed pullulan to maltotriose.

• Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.373-378
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• 2015

Postprandial ammonia excretion and oxygen consumption in olive flounder Paralichthys olivaceus fed two different feed types, moist pellet (MP) and expanded pellet (EP) diets, to satiation were determined at $12^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$ for 48 h. The ammonia excretion and oxygen consumption rates increased with increasing water temperature. However, the postprandial times for the maximum rates of ammonia excretion and oxygen consumption were shortened from 12 h to 6 h after feeding with increasing water temperature. The ammonia excretion and oxygen consumption rates of the fish fed EP were significantly higher (P < 0.05) than those fed MP at 12 h post-feeding both for $12^{\circ}C$ and $15^{\circ}C$. The highest (P < 0.05) weight-specific ammonia excretion rates at $12^{\circ}C$ were observed in the fish fed EP and MP at $12.1mg\;NH_3-N\;kg^{-1}h^{-1}$ and $8.7mg\;NH_3-N\;kg^{-1}h^{-1}$, respectively, for 12 h and 9 h after feeding. The highest (P < 0.05) weight-specific oxygen consumption rates at $12^{\circ}C$ were observed in fish fed EP and MP at $116.4mg\;kg^{-1}h^{-1}$ and $101.0mg\;kg^{-1}h^{-1}$, respectively, for 12 h after feeding. The highest ammonia excretion rates at $25^{\circ}C$ in the fish fed EP and MP increased to $16.9mg\;NH_3-N\;kg^{-1}h^{-1}$ and $18.3mg\;NH_3-N\;kg^{-1}h^{-1}$, respectively, for 6 h after feeding. The highest (P < 0.05) weight-specific oxygen consumption rates at $25^{\circ}C$ were observed in fish fed EP and MP at $184.3mg\;O_2kg^{-1}h^{-1}$ and $197.3mg\;O_2kg^{-1}h^{-1}$, respectively. These data are valuable for the design of biofilters and development of effluent treatment technologies for the land-based flounder farms.

• Journal of Microbiology
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• v.37 no.1
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• pp.14-20
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• 1999

Two extracellular proteases, EP I and EP II, from cells of Oligotropha carboxydovorans (formerly Pseudomonas carboxydovorans) DSM 1227 grown in nutrient broth were purified to greater than 95% homogeneity in five steps using azocasein as a substrate. The final specific activities of EPs I and II were 214.9 and 667.4 units per mg of protein. The molecular weights of native EPs I and II were determined to be 23,000. Sodium dodecyl sulfate-gel electrophoresis revealed the two enzymes to be monomers. The enzymes were found to be serine-type proteases. The activity of EP I was stimulated by Ca2+, Mg2+, and Ba2+, but that of EP II was not. The enzymes were completely inhibited by Fe2+, Hg2+, Co2+, Zn2+, and Cd2+. EDTA and EGTA exhibited a strong inhibitory effect on EP I. The optimal pH for the two enzymes was pH 9.0. The optimal temperatures for EP I and II were 60 and 50$^{\circ}C$, respectively. The enzymes were stable under alkaline conditions. The thermal stability of EP I was higher than that of EP II. Cell-free extracts did not inhibit the purified enzymes. The enzymes were active on casein, azocasein, azocoll, and carbon monoxide dehydrogenase, but weakly active with bovine serum albumin.

• Korean Journal of Animal Reproduction
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• v.26 no.1
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• pp.79-85
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• 2002

We investigated the optimal concentration and exposure time of cycloheximide(CHX) on development of activated porcine oocytes following electrical pulse(EP). After 42~44 h maturation, oocytes were treated with 0.1% hyaluronidase, and denuded cumulus cells by pipetting. Oocytes were stimulated by electric pulse (1.2 kV/cm, 30 $\mu$sec, 1 pulse) or incubated for 3, 5 and 7 h in cycloheximide (1, 5 and 10 $\mu\textrm{g}$/$m\ell$, respectively) following electric pulse, and cultured for 8 days. Cleavage rate of oocytes activated with 10 $\mu\textrm{g}$/$m\ell$ CHX following EP was significantly (P＜0.05) higher than those of 1 $\mu\textrm{g}$/$m\ell$ (86.8% vs. 74.4%). The developmental competence of oocytes incubated to 5 $\mu\textrm{g}$/$m\ell$ of CHX was significantly (P＜0.05) higher development to blastocysts (13.3%), compared with 10 $\mu\textrm{g}$/$m\ell$ of CHX (5.6%). When the oocytes were activated with 5$\mu\textrm{g}$/$m\ell$ CHX for 3, 5, and 7 h following EP, the cleavage rate of oocytes in 5 h group(86.6%) was significantly (P＜0.05) higher than that in 3 h group(73.2%). The developmental rate of oocytes to morula in 5 and 7 h groups(26.7% and 16.4%) were significantly (P＜0.05) high than that in 3 h group(14.5%). Matured oocytes were activated with electric pulse (EP) or electric pulse combined with cycloheximide (EP + CHX) and cultured for 8 days. The rate of cleavage and development to blastocyst (80.1% and 11.6%) of activated with EP group were similar to EP combined with CHX group. When activated with EP or EP combined with CHX, the mean cell number of blastocysts were less in the activated with EP (18.67$\pm$5.53) than in the activated EP combined CHX (20.71$\pm$6.16), but not significantly different. This results suggest that, when the porcine oocytes were activated with CHX following EP, the developmental rate of activated oocytes can be improved by treated with a concentration of 5 $\mu\textrm{g}$/$m\ell$ CHX for 5 h exposure time.

• Food Science and Preservation
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• v.20 no.2
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• pp.166-172
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• 2013

The effect of phytoncide solution treatment on the browning and quality of fresh-cut iceberg lettuce during storage was studied. The treatments were applied as four solutions adjusted at $10^{\circ}C$: distilled water (DW) as the control; edible ethanol (EE); 1% (v/v) phytoncide essential oil from pine needle diluted with distilled water (DP); and 1% (v/v) phytoncide essential oil diluted with edible ethanol (EP). Fresh-cut lettuce was dipped in each solution for 60 sec, was rinsed with distilled water, was packaged with an OPP film bag, and was then stored at $4^{\circ}C$ for 12 days. The EP group had a significantly high level of total soluble solids, titratable acidity, and carbon dioxide, and low total bacteria counts, pH, and oxygen. The sensory score of color in the EP group recorded a high value, but the EE and EP groups recorded low scores in aroma and taste during the storage period. Alcohol and phytoncide were vaporized by opening the package for two hours, and the score of the aroma and taste of EP showed no differences from those of the other groups. Based on the above results, it was determined that the phytoncide essential oil diluted in edible alcohol with 1% solution inhibited the browning of and microbial growth in fresh-cut lettuce, and will be a useful natural compound in maintaining the quality of fresh-cut produce.

• Fire Science and Engineering
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• v.33 no.5
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• pp.19-27
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• 2019

Fire extinguishing composite materials based on low-viscosity epoxy resin (EP) and containing 50 wt% of encapsulated fire extinguishing agent (EFA) have been studied. The positive effect of the EP on the kinetics and temperature of the EFA decapsulation was established. The EP increases the decapsulation temperature of the EFA from 130 ℃ to 155 ℃ and changes the kinetics of the decapsulation. The epoxy matrix increases the thermal stability of the EFA more than 3.9 times compared to that of the pure EFA. The protective effect of the EP on the storage stability of the EFA was validated. The mass loss of EP-containing EFA at 60 ℃ and 80% humidity over 96 h is 0.4%. The mass loss of pure EFA under the same conditions is 15%. A similar effect was observed under ultraviolet radiation: the EP-containing EFA loses 0.8% at pure EFA mass of 6%. The testing of alternative polymer matrixes has been considered.

• Applied Biological Chemistry
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• v.21 no.2
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• pp.109-111
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• 1978

This study was undertaken in order to observe the differences of the changes in the water-holding capacity (WHC), extractability of proteins (EP) and pH value of ovine muscle during storage. WHC decreased gradually after slaughter, reached to minimum at about 2-4hr after death as well as that of pH value and then these were recovered along with the progress of the storage. The same tendency was observed in EP but the degree of the changes in pH value up to 6hr after slaughter was more rapid this that of WHC and EP. After the fourth day, the rate of recovery in WHC, EP and pH value in ovine muscle during storage showed similar pattern.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3248-3252
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• 2012

Vibrio extracellular metalloprotease (vEP), secreted from Vibrio vulnificus, shows various proteolytic function such as prothrombin activation and fibrinolytic activities. Premature form of vEP has an N-terminal (nPP) and a C-terminal (C-ter100) region. The nPP and C-ter100 regions are autocleaved for the matured metalloprotease activity. It has been proposed that two regions play a key role in regulating enzymatic activity of vEP. Especially, C-ter100 has a regulatory function on proteolytic activity of vEP. C-ter100 domain has been cloned into the E. coli expression vectors, pET32a and pGEX 4T-1 with TEV protease cleavage site and purified using gel-filtration chromatography followed by affinity chromatography. To understand how C-ter100 modulates proteolytic activity of vEP, structural studies were performed by heteronuclar multi-dimensional NMR spectroscopy. Backbone $^1H$, $^{15}N$ and $^{13}C$ resonances were assigned by data from standard triple resonance and HCCH-TOCSY experiments. The secondary structures of vEP C-ter100 were determined by TALOS+ and CSI software based on hydrogen/deuterium exchange. NMR data show that C-ter100 of vEP forms a ${\beta}$-barrel structure consisting of eight ${\beta}$-strands.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.715-730
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• 2021

The objective of this study was to evaluate antioxidant activities of eggplant (EP) powder with different drying methods and addition levels to pork sausages to improve product quality. Antioxidant activities of EP with different drying methods, particle sizes, and solvents of extraction were determined. Freeze dried (FD) EP extracted with 100% ethanol had higher 2,2-diphenyl-1picrylhydrazyl radical-scavenging activities (DPPH-RSA) and total phenolic content (TPC) values than other drying methods. FD500 had the highest iron chelating ability (ICA) value. Oven-dried (OD) EP at 60℃ had the highest reducing power. Dried EP was added to sausages of six groups: control without EP, reference added with ascorbic acid, O1 and O2 added with 0.25% and 0.5% OD EP, respectively, and F1 and F2 added with 0.25% and 0.5% FD EP, respectively. Pork sausages added with O2 had the lowest TBARS and TPC values. These values increased during storage. Purge loss (%), lightness (L^*), and redness (a^*) values of F2 were lower than those of other groups, whereas sausages containing F2 had the highest yellowness (b^*). pH values of sausages added with EP were increased regardless of the level of EP added. Hardness values of F2 were higher. However, there were no significant differences in other textural characteristics. Sausages added with EP had higher moisture and protein contents (%), but lower fat contents (%). These results indicate that EP powder could be used to retard lipid oxidation and inhibit microbial counts during storage time.