• 대한의생명과학회지
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• 제11권3호
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• pp.349-353
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• 2005

The globin in cytosol receives the heme in mitochondria and folds to the hemoglobin within erythrocyte. Two mechanisms have been proposed that the heme was transfered post-translationally or cotranslationally to the globin. In this research, how the globin in cytosol receives post-translationally the heme from membranes was studied according to pH and phospholipid composition. Globins dissolved in various pH buffer solutions $(PH\;3\~7)$ were rapidly added into the bulk of egg phosphatidylcholine $100\%\;or\;60\%$ liposomes containing hemin in pH 7 buffer solution. Hemin was very highly transferred to globin at pH 4 and 6. Also, hemin was more efficiently transfered to globin in egg phosphatidylcholine $100\%$ than in $60\%$ liposomes.

• Animal cells and systems
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• 제8권2호
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• pp.105-109
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• 2004

Aminoalcoholphosphotransferase catalyzes the synthesis of phosphatidylcholine and phosphatidylethanolamine from diacylglycerol plus a CDP-aminoalcohol such as CDP-choline or CDP-ethanolamine. Previously we suggested the presence of possible isoforms of this enzyme from Chinese cabbage roots and now report the cDNA cloning and expression analysis of AAPT3 encoding a third isoform of aminoalcoholphosphotransferase (AAPT3). AAPT3 contains an open reading frame of 1,176 bp coding for a protein of 392 amino acids. It shares 96 and 95% identity with Chinese cabbage AAPT1 and AAPT2, respectively, at the deduced amino acid level. The results from reverse transcriptase-polymerase chain reaction analysis indicate that expression of AAPT3 is up-regulated by low temperature as well as AAPT1 and AAPT2.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1376-1378
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• 1994

Azobenzene derivative is so stiff that monolayer cannot be formed on the subphase. To form a monolayer on the subphase, azobenzene derivative was mixed arachidic acid. It didn't form a monolayer, either. The mixture of azobenzene derivative and L-${\alpha}$-phosphatidylcholine generated a monolayer on the wafer subphase. Thickness of LB film layered at 30 mN/m was about $70{\AA}$. The polarized UV-visible absorption spectra of the mixture exhibited a dichroic ratio of azobenzene derivative and L-${\alpha}$-phosphatidylcholine.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.125-129
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• 1999

The influence of dietary cholesterol on phospolipid metabolism in rat liver microsmes was studied in rats fed a diet containing fish oil(FO) or beef tallow (BT). The hepatic phospholipid content decreased wherease gepatic triglyceride and cholesterol increased significantly in both groups after cholestered supplementation. Plasma concentrations of phospholipid and traiglyceride increased with cholesterol supplement in both groups while cholesterol decreased only moderately in the FO group. Dietary cholesterol affected microsomal phosphiolpids in liver ; the proportation of phosphatidylcholine decreased in the FO group, an d it also slightly decreased in the BT group at the expense of phosphatidylethanolamine. The activity of CTP : phospocholine cytidylytransferase , the rate-limiting enzyme of phosphatidylcholine synthesis, increased inhepatic mocrosomes whreas it decreased in hepatic cytosol of both groups by cholesterol supplementation. In conclusion, these indicated that the dietary cholesterol profoundly influences phospholipid metabolism in the rat liver.

• Archives of Pharmacal Research
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• 제20권3호
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• pp.218-224
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• 1997

Platelet-activating factor (PAF) acetylhydrolase, which removes the acetyl moiety at the sn-2 position, has been found in human amniotic fluid. We purified this enzyme by ammonium sulfate precipitation, and sequential use of DEAE-Sepharose CL-6B, hydroxyapatite, chelating-Sepharose, and Mono Q column chromatographies. This enzyme exhibited broad pH optima and was unaffected by EDTA. Partially purified enzyme had a molecular weight of approximately 34 kDa on SDS-PAGE. In addition, the enzyme activity was inhibited by either diisopropylfluorophosphate(DFP) or p-bromophenacylbromide (p-BPB), suggesting that this enzyme possesses active serine and histidine residues. The enzyme showed similar activity towards PAF and oxidatively modified phosphatidylcholine, but didn't hydrolyze phosphatidylcholine or phosphatidylethanolamine with a long chain fatty acyl group at sn-2 position.

• Bulletin of the Korean Chemical Society
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• 제17권10호
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• pp.905-908
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• 1996

A substrate specificity of cabbage phospholipase D (PLD) was studied using the synthetic phospholipids having different head groups. The phospholipids were synthesized from phosphatidylcholine and appropriate bases by transphosphatidylation of PLD. The bases used were ethanolamine, serine, ethanol and γ-hydroxybutyric acid. The phosphatidic acid, the product of PLD, was separated in TLC and measured densitometrically. The kinetic parameters were estimated for each substrate and the effects of pH, SDS, Ca2+ and other metal ions were examined. Vmax values found were 3.75, 2.36, 5.59, 1.63, 2.30 nmol/min/μg protein for phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylethanol, and phosphatidylburytic acid, respectively. These results indicate a broad specificity of cabbage PLD toward phospholipids with different head groups. Particularly phosphatidylserine was most easily hydrolyzed by PLD and its activity did not depend on Ca2+.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.239.2-239.2
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• 2003

The purpose of this study was to evaluate the predictability of the fraction of drug absorbed in humans using the immobilized artificial membrane phosphatidylcholine column (IAMPC) under optimized conditions in comparison with a conventional IAMPC method. Twenty commercial drugs, both acidic and basic in nature, were used in the study, Drugs were dissolved in acetonitrile:water (50:50, v/v) at a concentration of 100 mg/ml, and were injected on HPLC/UVD at a mobile phase (acetonitrile:DPBS = 10:90,v/v) with a flow rate of 0.5 ml/min equilibrated at 37$^{\circ}C$. (omitted)

• 한국영양학회:학술대회논문집
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• 한국영양학회 1995년도 추계학술대회 초록
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• pp.42-42
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• 1995

• 한국독성학회:학술대회논문집
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• 한국독성학회 1997년도 국제 심포지움 및 춘계 학술대회
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• pp.65-74
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• 1997

By using guinea pig lung mast cells, this study aimed to examine the effects of Aloe component(NY945) on the mediator releases caused by mast cell activation, and also aimed to assess the effects of NY945 on the mechanism of mediator releases in the mast cell activation. We partially purified mast cells from guinea pig lung tissues by using the enzyme digestion, the rough and the discontinuous density percoll gradient method. Mast cells were sensitized with $IgG_1$ (anti-OA) and challenged with ovalbumin. Histamine was assayed by fluorometric analyzer, leukotrienes by radioimmunoassay The phospholipase D activity was assessed more directly by the production of labeled phosphatidylethanol or phosphatidylbutanol which was produced by phospholipase D-mediated transphosphatidylation in the presence of ethanol or butanol. The amount of mass 1,2-diacylglycerol was measured by the [$^3H$]1,2-diacylgycerol produced when prelabeled with [$^3H$]myristic acid. In the mast cells prelabeled with L-[$^3H$]methyl methionine the phospholipid methylation was assessed by measuring the incorporation of the [$^3H$]methyl moiety into phospholipids. Pretreatment of NY945(10$\mu$g) significantly decreased histamine and leukotrienes releases during mast cell activation. The decrease of histamine release was stronger than that of leukotrienes during mast cell activation. The phospholipase D activity increased by the mast cell activation was decreased by the dose-dependent manner in the pretreatment of NY945. The amount of mass 1,2-diacylglycerol produced by activation of mast cells were decreased in the pretreatment of NY945. NY945 pretreatment strongly inhibited the incorporation of the [$^3H$]methyl moiety into phospholipids. The data suggest that NY945 purified from Aloe inhibits in part an increase of 1,2-diacylglycerol which is produced by activating mast cells with antigen-antibody complexes which is mediated via phosphatidylcholine-phospholipise D and phosphatidylinositole-phospholipise C systems, and then followed by the inhibition of histamine release. Furthermore, NY945 reduces the phosphatidylcholine production by inhibiting the methyltransfsrase I and II, which decrease the conversion of phosphatidylcholine into arachidonic acid and inhibits the production of leukotrines.

• 대한화학회지
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• 제47권5호
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• pp.466-471
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• 2003

양배추 포스포리파제 D(PLD)에 대한 포리아민들의 영향을 조사하였다. PLD 활성도는 phosphatidylcholine small unilamellar 베시클을 기질로 하여 pH- stat 방법으로 생성물질 phosphatidic acid를 적정하여 결정하였다. 양배추 PLD는 스퍼민 1 mM 농도에서 약 4배 활성화되었다. 이 스퍼민 효과는 전에 보고된 쥐 뇌 미토콘드리아 분획의 PLD 활성과 유사한 결과를 보여주고 있다. 양이온성 polypeptide인 polylysine과 polyhistidine에 의해서도 양배추 PLD가 상당히 활성화되는 것을 알았다. 특히 polyhistidine은 0.062 mM 농도에서 약 5.5배의 활성화 효과를 나타냈다. 이 포리아민 효과는 phosphatidylcholine/sodium dodecyl sulfate 혼합미셀계에서도 재확인하였다. 포리아민에 대한 PLD 활성화의 의미를 PLD 활성부위와 관계 지워 고찰하였다.