• Bulletin of the Korean Chemical Society
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• v.10 no.1
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• pp.69-71
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• 1989

Effects of SDS and temperature on the conformational changes of bacteriorhodopsin were studied using a, b, c bands of bacteriorhodopsin. In the SDS denaturation, bacteriorhodopsin in purple membrane was more labile than bacteriorhodopsin reconstituted into PC vesicles. These rather interesting results may be understood by effective SDS concentration in lipid layer.

• Molecules and Cells
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• v.38 no.6
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• pp.573-579
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• 2015

Apolipoprotein A-I and A-IV are protein constituents of high-density lipoproteins although their functional difference in lipoprotein metabolism is still unclear. To compare anti-atherogenic properties between apoA-I and apoA-4, we characterized both proteins in lipid-free and lipidbound state. In lipid-free state, apoA4 showed two distinct bands, around 78 and $67{\AA}$ on native gel electrophoresis, while apoA-I showed scattered band pattern less than $71{\AA}$. In reconstituted HDL (rHDL) state, apoA-4 showed three major bands around $101{\AA}$ and $113{\AA}$, while apoA-I-rHDL showed almost single band around $98{\AA}$ size. Lipid-free apoA-I showed 2.9-fold higher phospholipid binding ability than apoA-4. In lipid-free state, $BS_3$-crosslinking revealed that apoA-4 showed less multimerization tendency upto dimer, while apoA-I showed pentamerization. In rHDL state (95:1), apoA-4 was existed as dimer as like as apoA-I. With higher phospholipid content (255:1), five apoA-I and three apoA-4 were required to the bigger rHDL formation. Regardless of particle size, apoA-I-rHDL showed superior LCAT activation ability than apoA-4-rHDL. Uptake of acetylated LDL was inhibited by apoA-I in both lipid-free and lipid-bound state, while apoA-4 inhibited it only lipid-free state. ApoA-4 showed less anti-atherogenic activity with more sensitivity to glycation. In conclusion, apoA-4 showed inferior physiological functions in lipid-bound state, compared with those of apoA-I, to induce more pro-atherosclerotic properties.

• Bulletin of the Korean Chemical Society
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• v.25 no.2
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• pp.237-242
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• 2004

Recombinant human ferritin homopolymers (rHF and rLF) were successfully produced in the Saccharomyces cerevisiae Y2805, which was transformed with human ferritin H or L-chain genes, respectively. In order to characterize the molecular properties of the recombinant ferritins in relation to mineralization, the proteins were isolated and apoferritins were prepared. The apoferritins were reconstituted with 2000 Fe atoms per protein molecule under various experimental conditions (the concentration of the protein, the buffer concentration of the MOPS buffer, the total volume of the reaction and the reconstitution method). The structure and composition of the iron cores formed in the ferritins were examined using transmission electron microscopy. The recombinant ferritins behaved in a similar manner to other mammalian ferritins in accumulating iron in the core. Proteins of rHF and rLF showed varying reconstitution yields of 37-72% depending on the reaction conditions. In general, the rHF showed higher reconstitution yield than the rLF at the protein concentrations and the reaction volumes we examined. Iron cores with a similar mean particle size were obtained in the rHF, rLF and horse spleen ferritin reconstituted at a protein concentration of 1.0 mg/mL. Electron diffraction of all the three ferritins showed 2-3 diffuse lines, with d-spacings corresponding to those of the mineral ferrihydrite with a limited crystallinity.

• YAKHAK HOEJI
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• v.50 no.5
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• pp.301-307
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• 2006

A simple and sensitive high-performance liquid chromatographic method for quantitation of hydrochlorothiazide in human plasma was developed and bioavailability parameters of hydrochlorothiazide were assessed in Korean healthy male volunteers. Caffeine was used as an internal standard. Hydrochlorothiazide and internal standard in plasma sample were extracted using tert-butylmethylether (TBME). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of acetonitrile-25 mM phosphate buffer (20/80, pH 2.5). The reconstituted samples were injected into a Luna C18 column $(250{\times}4.6\;mm,\;5{\mu}m)$ at a flow-rate of 1.0 ml/min. The wavelength was set at 230 nm and no endogenous substances were found to interfere, A linear relationship for hydrochlorothiazide was found in the range of $10{\sim}300\;ng/ml$. The lower limit of quantitation (LLOQ) was 10 ng/ml with acceptable precision and accuracy. Assayed in plasma, the intra- and inter-day validation for all coefficients of variation (R.S.D.%) were found less than 15%. Main pharmacokinetic parameters of 50mg of hydrochlorothiazide were revealed as follows: $AUC_t\;1761{\pm}509.0\;ng{\cdot} hr\;ml,\;C_{max}\;296.5{\pm}95.5\;ng/ml,\;T_{max}\;1.94{\pm}0.85hr,\;K_{el}\;0.12{\pm}0.04\;hr^{-1}\;and T_{12}\;6.81{\pm}2.92\;hr.\;C_{max}\;and\;T_{max}$ were in accordance with the values $(270{\sim}350\;ng/ml\;and\;1.9{\sim}2.7\;hr)$ of Caucasian.

• Journal of the Korean Geotechnical Society
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• v.27 no.9
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• pp.37-46
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• 2011

The compression index, which represents the compressibility of clay, is generally obtained from the consolidation test, or has been predicted by empirical correlations with soil properties. In this study, the results of consolidation tests on natural and reconstituted Busan and Inchon clays are analyzed to figure out the sedimentation state and its effect on empirical correlations. Results of analysis show that the void index of Busan clay is higher than SCL while the void index of Inchon clay is lower than SCL. By comparing prediction errors with ${\Delta}e_r$, which represents the sedimentation state of clay, it is shown that errors predicting the compressibility based on the liquid limit and plasticity index decrease as ${\Delta}e_r$ increases. Supplemented correlations predicting the compression index of Busan and Inchon clays are suggested using these relationships.

• Molecules and Cells
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• v.27 no.3
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• pp.291-297
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• 2009

Apolipoprotein (apo) C-III is a marker protein of triacylglycerol (TG)-rich lipoproteins and high-density lipoproteins (HDL), and has been proposed as a risk factor of coronary heart disease. To compare the physiologic role of reconstituted HDL (rHDL) with or without apoC-III, we synthesized rHDL with molar ratios of apoA-I:apoC-III of 1:0, 1:0.5, 1:1, and 1:2. Increasing the apoC-III content in rHDL produced smaller rHDL particles with a lower number of apoA-I molecules. Furthermore, increasing the molar ratio of apoC-III in rHDL enhanced the surfactant-like properties and the ability to lyse dimyristoyl phosphatidylcholine. Furthermore, rHDL containing apoC-III was found to be more resistant to particle rearrangement in the presence of low-density lipoprotein (LDL) than rHDL that contained apoA-I alone. In addition, the lecithin:cholesterol acyltransferase (LCAT) activation ability was reduced as the apoC-III content of the rHDL increased; however, the CE transfer ability was not decreased by the increase of apoC-III. Finally, rHDL containing apoC-III aggravated the production of MDA in cell culture media, which led to increased cellular uptake of LDL. Thus, the addition of apoC-III to rHDL induced changes in the structural and functional properties of the rHDL, especially in particle size and rearrangement and LCAT activation. These alterations may lead to beneficial functions of HDL, which is involved in anti-atherogenic properties in the circulation.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.6
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• pp.641-645
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• 1995

This study was conducted to develop a method for production of nuclear transplant bovine embryos using in vitro-matured (IVM) oocytes and to examine the effect of different conditions of electrofusion on fusion rate and developmental capacity of donor nucleus transplanted to enucleated oocytes. Eight- to sixteen-cell embryos derived from oocytes matured and fertilized in vitro used as donor blastomeres and IVM oocytes were used as recipient oocytes. Oocytes were enucleated immediately after 23-24 h IVM and then reconstituted with a donor blastomere in two different micromanipulation media. Fusion rate and subsequent development of the reconstituted oocytes was compared under the different electric stimuli and recipient oocyte ages. Success rate of enucleation was significantly higher in TCM-199 medium containing FCS than in DPBS. The high fusion rate(75-94%) and development (6.4-14.8%) to morulae and blastocyst (M + B) were obtained from 0.6-0.75 kV/cm DC voltage, although total cleavage was not different among the electric pulses. Most optimal condition of electric stimulation for fusion and development was 1 DC voltage of 0.75 kV/cm, in which 80.5% of oocytes were fused, 80.0% and 31.7% of which was cleaved and developed to M + B, respectively. No M + B was obtained from 1.2 kV/cm DC voltage regardless of pulse frequency. Recipint oocyte age at electrofusion greatly affected the cleavage and subsequent development to M + B, showing high rate at 40-41 h oocyte maturation. These results suggest that a suitable condition of electrofusion for donor nuclei derived from IVF may be 1-2 DC pulses of 0.7 kV/cm for $70{\mu}sec$ and that processing of a transplanted nucleus in IVM oocytes may be affected by maturation age of recipient oocytes.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.34-44
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• 1984

This experiment was carried out to obtain the fundamental data for development of digestibility and quality enhanced product of soy yogurt. Soy yogurt was processed from raw materials of soybean, defatted soybean and sprouted soybean which inoculated with Lactobacillus acidophilus and Bifidobacterium bifidum as a starter. Changes of chemical compositions, viable cell count and saccharides during processing were investigated including acceptibility of manufactured products. The results were summarized as follows; 1. Defatted soy milk ferment ed with Lactobacillus acidophilus was showed the greatest initial acid productivity and sprouted soy milk was showed the greatest growth of Loctobacillus acidophilus. 2. Acid production was accelerated when 2% glucose was used in soy milk. 3. Addition of reconstituted skim milk in soy milk and defatted roy milk increased acid production but was not showed the effect in the sprouted soy milk. 4. Sprouting soybean, the contents of raffinose and stachyose were decreased but those of glucose was increased. 5. When soy milk was fermented with Lactobacillus acidophilus. the contents of raffinose and stachyose were decreased. 6. As a result of panel test, sprouted soy yogurt which was produced by addition of reconstituted skim milk of 10% showed the greatest flavor and tastes.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2076-2086
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• 2016

Fungal cytochrome P450 (CYP) enzymes catalyze versatile monooxygenase reactions and play a major role in fungal adaptations owing to their essential roles in the production avoid metabolites critical for pathogenesis, detoxification of xenobiotics, and exploitation avoid substrates. Although fungal CYP-dependent biotransformation for the selective oxidation avoid organic compounds in yeast system is advantageous, it often suffers from a shortage avoid intracellular NADPH. In this study, we aimed to investigate the use of bacterial glucose dehydrogenase (GDH) for the intracellular electron regeneration of fungal CYP monooxygenase in a yeast reconstituted system. The benzoate hydroxylase FoCYP53A19 and its homologous redox partner FoCPR from Fusarium oxysporum were co-expressed with the BsGDH from Bacillus subtilis in Saccharomyces cerevisiae for heterologous expression and biotransformations. We attempted to optimize several bottlenecks concerning the efficiency of fungal CYP-mediated whole-cell-biotransformation to enhance the conversion. The catalytic performance of the intracellular NADPH regeneration system facilitated the hydroxylation of benzoic acid to 4-hydroxybenzoic acid with high conversion in the resting-cell reaction. The FoCYP53A19+FoCPR+BsGDH reconstituted system produced 0.47 mM 4-hydroxybenzoic acid (94% conversion) in the resting-cell biotransformations performed in 50 mM phosphate buffer (pH 6.0) containing 0.5 mM benzoic acid and 0.25% glucose for 24 h at $30^{\circ}C$. The "coupled-enzyme" system can certainly improve the overall performance of NADPH-dependent whole-cell biotransformations in a yeast system.

• Development and Reproduction
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• v.17 no.1
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• pp.9-16
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• 2013

Coactivator-associated arginine methyltransferase 1 (CARM1) is included in the protein arginine methyltransferase (PRMT) family, which methylates histone arginine residues through posttranslational modification. It has been proposed that CARM1 may up-regulate the expression of pluripotency-related genes through the alteration of the chromatin structure. Mouse embryonic stem cells (mESCs) are pluripotent and have the ability to self-renew. The cells are mainly used to study the genetic function of novel genes, because the cells facilitate the transmission of the manipulated genes into target mice. Since the up-regulated methylation levels of histone arginine residue lead to the maintenance of pluripotency in embryos and stem cells, it may be suggested that CARM1 overexpressing mESCs elevate the expression of pluripotency-related genes in reconstituted embryos for transgenic mice and may resist the differentiation into trophectoderm (TE). We constructed a fusion protein by connecting CARM1 and 7X-arginine (R7). As a cell-penetrating peptide (CPP), can translocate CARM1 protein into mESCs. CPP-CARM1 protein was detected in the nuclei of the mESCs after a treatment of 24 hours. Accordingly, the expression of pluripotency-related genes was up-regulated in CPP-CARM1-treated mESCs. In addition, CPP-CARM1-treated mESC-derived embryoid bodies (EBs) showed an elevated expression of pluripotency-related genes and delayed spontaneous differentiation. This result suggests that the treatment of recombinant CPP-CARM1 protein elevates the expression of pluripotency-related genes of mESCs by epigenetic modification, and this protein-delivery system could be used to modify embryonic fate in reconstituted embryos with mESCs.