• Journal of Life Science
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• v.21 no.8
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• pp.1134-1141
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• 2011

Transmembrane protein 21 (TMP21) is a member of the p24 cargo protein family and has been shown to modulate ${\alpha}$-secretase-mediated A${\beta}$ production which was specifically observed in the brains of subjects with Alzheimer's disease (AD). In order to investigate whether TMP21 could affect nerve growth factor (NGF) receptor signaling pathway, the alteration of NGF receptors and their downstream proteins were detected in TMP21 over-expressed cells. CMV/hTMP21 vector used in this study was successfully expressed into TMP21 proteins in B35 cells after lipofectamin transfection. Expressed TMP21 proteins induced the down-regulation of ${\gamma}$-secretase complex components including Presenlin-1 (PS-1), PS-2, Nicastrin (NST), Pen-2 and APH-1. Also, the expression level of NGF receptor $p75^{NTR}$ and RhoA were significantly higher in CMV/hTMP21 transfectants than vehicle transfectants, while their levels returned to vehicle levels after NGF treatment. However, the phosphorylation of NGF receptor TrkA was dramtically decreased in NGF No-treated CMV/hTMP21 transfectants compared with vehicle transfectants, and increased in NGF treated CMV/hTMP21 transfectants. In TrkA downstream signaling pathway, the phosphorylation level of ERK was also decreased in CMV/hTMP21 transfectants, while the phosphorylation of Akt was increased in the same transfectants. Furthermore, NGF treatment induced the increase of phosphorylation level of Akt and ERK in CMV/hTMP21 transfectants. Therefore, these results suggested that over-expression of TMP21may simultaneously induce the up-regulation of $p75^{NTR}$/RhoA expression and the down-regulation of TrkA/ERK phosphorylation through the inhibition of ${\gamma}$-secretase activity.

• BMB Reports
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• v.44 no.6
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• pp.369-374
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• 2011

MHC-I molecules play a critical role in immune surveillance against viruses by presenting peptides to cytotoxic T lymphocytes. Although the mechanisms by which MHC-I molecules assemble and acquire peptides in the ER are well characterized, how MHC-I molecules traffic to the cell surface remains poorly understood. To identify novel proteins that regulate the intracellular transport of MHC-I molecules, MHC-I-interacting proteins were isolated by affinity purification, and their identity was determined by mass spectrometry. Among the identified MHC-I-associated proteins was Tmp21, the human ortholog of yeast Emp24p, which mediates the ER-Golgi trafficking of a subset of proteins. Here, we show that Tmp21 binds to human classical and non-classical MHC-I molecules. The Tmp21-MHC-I complex lacks ${\beta}_2$-microglobulin, and the number of the complexes is increased when free MHC-I heavy chains are more abundant. Taken together, these results suggest that Tmp21 is a novel protein that preferentially binds to ${\beta}_2$-microglobulin-free MHC-I heavy chains.

• Journal of Life Science
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• v.21 no.4
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• pp.596-603
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• 2011

This study was conducted to investigate traditional medicinal plants (TMP) 1 and 2, two different multi-herbal mixtures consisting of 24 herbs. Regarding the contents of flavonoid compounds, the ethanol extract (EE) of TMP2 yielded the highest content of flavonoid compounds (40.981 mg/g), followed by EE of TMP1 (28.23 mg/g), hot water extract of TMP2 (WE, 10.046 mg/g), and WE of TMP1 (6.59 mg/g). Antioxidant activities of EE and WE of TMP1 and TMP2 were measured based on DPPH radical scavenging activity. At 1 mg/ml, the highest DPPH radical scavenging activity was shown in EE of TMP2 (96%), followed by EE of TMP1 (94%). Nitric oxide (NO) production by RAW264.7 macrophage cells stimulated with lipopolysaccharide (LPS) was reduced to 82, 77, 86, and 47% by addition of $500\;{\mu}g/ml$ of EE and WE of TMP1 and TMP2, respectively. These results were not due to the cytotoxicity of the extracts. NO synthesis was increased by 2.3, 3.6, 3.0, and 1.8 fold by addition of $500\;{\mu}g/ml$ of EE and WE of TMP1 and TMP2, respectively. These results show that medicinal plants play a significant role in antioxidative activity and activation of the immune system in the pathogenesis of inflammatory diseases, and different mixtures of the medicinal plants showed different effects.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.2
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• pp.16-21
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• 2014

Characteristics of coating color penetration into paper were elucidated using various types of pulps and pigments. A commercial paper, KP and TMP handsheets were used for base paper. Clay and GCC were used as coating pigment. Laboratory rod draw down coater was used for coating application. Coating color penetration was evaluated by measuring the roughness of surface and back side of a coating layer. The results of coating roughness showed that clay was much better than GCC as a coating pigment. In case of pulp type, KP base paper was more effective than TMP base paper to reduce coating penetration.

• Journal of the Korean Chemical Society
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• v.39 no.11
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• pp.837-841
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• 1995

Thermodynamic parameters for the hydrogen bonding between thiopropionamide(TPA) and proton donors such as triethylphosphine oxide(TEPO), triphenylphosphine oxide(TPPO), trimethylphosphate(TMP), and tributyl phosphate(TBP) in dilute carbon tetrachloride solution have been measured by near-IR spectroscopy. The νa + amide Ⅱ combination band of TPA has been resolved into two Lorentzian-Gaussian product components which have been identified with monomeric TPA and 1 : 1 hydrogen bonded complex. The equilibrium constants and thermodynamic parameters for the formation of 1 : 1 hydrogen bonded complex have been obtained by the analysis of concentration and temperature dependent spectra. The standard enthalpies for the 1 : 1 hydrogen bonded complex formation of TPA with TEPO, TPPO, TMP, and TBP in CCl4 have been found to be - 21.4, - 16.8, - 12.8, and - 12.9 kJ/mol, respectively. The results are explained by the inductive and steric effects of substituents.

• Membrane Journal
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• v.21 no.4
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• pp.360-366
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• 2011

The effect of cross-flow velocity and transmembrane pressure (TMP) on membrane fouling was observed from pilot-scale operation of thermophilic anaerobic membrane bioreactor (AnMBR) treating food waste leachate. It was found that fouling rate was reduced significantly as cross-flow velocity increased at constant TMP mode of operation while this effectiveness was more pronounced at lower TMP. Higher TMP resulted in less permeable fouling layer possibly due to compressibility of foulant material on membrane surface. Particle sizes of membrane concentrate ranged from 10 to $100{\mu}m$, implying that shear-induced diffusion enhance back transport of these particle sizes away from the membrane effectively. From the continuous operation of AnMBR, it was confirmed that shear rate played an important role in the reduction of membrane fouling. Membrane autopsy works at the end of operation of AnMBR showed clearly that both organic and inorganic fouling were significant on membrane surface. Surface shear by cross-flow velocity was expected to be less effective to remove irreversible fouling which can be mainly caused by the adsorption of organic colloidal materials into membrane pores.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.185-188
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• 2001

We have developed a synthetic method for dTDP-4-keto-6-deoxy-D-glucose with four enzyme system. We have used crude extracts from cultures of Escherichia coli BL21 strains harboring plasmids containing different sources. dTDP-4-keto-6-deoxy-D-glucose was synthesized by the combination of thymidine-monophosphate kinase, acetate kinase, dTDP-glucose synthase and dTDP-D-glucose 4,6-dehydratase in a batch system, starting the reaction with dTMP. The enzymatic synthesis strategy allowed a dTMP conversion with a 95%.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.493-501
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• 2007

The membrane pilot plant has being operated in the Hyeondo pumping station to find the optimal operation technique of Gong-Ju membrane water treatment plant (WTP) which is constructing in $250m^3/d$ scale. The pilot plant was consisted of two trains which can treat $30,000m^3/d$ per train. First train was operated for one year under the condition of flux $1m^3/m^2{\cdot}d$ while the effects of flux variation and addition of powdered activated carbon(PAC) were evaluated in second train. The turbidity of membrane product water of first train which is operated on Flux $1m^3/m^2{\cdot}d$ was always below 0.05 NTU regardless of raw water turbidity. And also, the trance-membrane pressure(TMP) was maintained at $0.3{\sim}0.5kgf/cm^2$ for about 9 months and increased rapidly to $1.8kgf/cm^2$ which is maximum operating TMP. However, TMP was rapidly increased to $1.8kgf/cm^2$ within 2 months as flux was increased from 1 to $2m^3/m^2{\cdot}d$, especially, within 10 days under high turbidity(30~50NTU). This reault means that if Gongju membrane WTP is operated in flux $1m^3/m^2{\cdot}d$, chemical cleaning period can be maintained over 6 months. Only 10% of dissolved organic carbon (DOC) was removed in membrane process while the removal efficiencies of manganese and iron were 60% and 77% respectively. However, because only solid manganese and iron were removed in membrane process, an additional process for treating soluble manganese is required if souble manganese is high in raw water. 70% of 70ng/L 2-MIB which is causing taste & odor was removed in powdered activated carbon (PAC) tank with 50mg/L PAC which is design concentration of Gongju WTP. In addition, TMP was reduced with addition of 50mg/L PAC regardless of flux. Because TMP was not influenced even if 100mg/L PAC was added, the high taste and odor problem can be controled by additional injection of PAC.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.2
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• pp.195-201
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• 2007

A submerged flat-sheet membrane separation system integrated with PAC (powdered activated carbon) was used in this research in order to investigate the effects of PAC on the efficiencies of operation and treatment and to evaluate the performance of the system. The experiments were carried out under operating conditions of a filtration rate of 0.38 m/d, water temperature of $20-28^{\circ}C$, and PAC dose of 0 g/L (Run-A) and 20 g/L (Run-B). The influent concentrations of TOC (total organic carbon), $NH_4{^+}-N$ (ammonia nitrogen) and $UV_{254}$ (UV absorbance at 254 nm) were 2.48 mg/L, 1.4 mg/L and 2.53 1/m, respectively. TOC removal of 43.2 and 73.6%, ammonia nitrogen removal of 4.9 and 15.9%, and $UV_{254}$ removal of 20.6 and 31.6% were obtained for Run-A and Run-B, respectively. During an experimental period of 33 days, no change was found in TMP (Run-B), but the TMP in Run-A increased by 5 kPa after 29 days. This research showed that the filtrate quality and the performance efficiency were enhanced when PAC was introduced into the filtration system.