• Title/Summary/Keyword: 인산화반응

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Dephosphpoylation of P-Nitrophenyldiphenylphosphinate by Benzimidazole Catalyzed with Ethyl tri-n-octyl Ammonium Bromide(ETABr) (ETABr 용액내에서 P-Nitrophenyldiphenylphosphinate의 탈인산화반응에 미치는 Benzimidazole의 촉매효과)

  • Kim, Jeung-Bea;Kim, Hak-Yoon
    • Journal of Environmental Science International
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    • v.16 no.5
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    • pp.641-647
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    • 2007
  • The phase transfer catalysis(PTC) reagent, ethyl tri-octyl ammonium bromide(ETABr), strongly catalyzes the reaction of p-nitrophenyi diphenyl phosphinate(p-NPDPIN) with benzimidazole(BI) and its anion($BI^{\theta}$). In ETABr solutions, the dephosphorylation reactions exhibit higher first order kinetics with respect to the nucleophile, BI, and ETABr, suggesting that reactions are occuring in small aggregates of the three species including the sub-strate(p-NPDPIN), whereas the reaction of p-NPDPIN with $OH^{\theta}$ is not catalyzed by ETABr. This behavior for the drastic rate-enhancement of the dephosphorylation is referred as 'aggregation complex model' for reaction of hydrophobic organic phosphinates with benzimidazole(BI) in hydrophobic quarternary ammonium salt(ETABr) solutions.

Chemical Reactions in Surfactant Solutions (Ⅳ) : Micellar Rate Effect on Reactions of Hydroxide and o-Iodosobenzoate Ions with Organic Phosphinates (계면활성제 용액속에서의 화학반응 (제 4 보) : $OH^-$ 및 o-Iodosobenzoate 이온에 의한 유기 포스피네이트의 탈인산화 반응에 미치는 CTAX 미셀의 영향)

  • Hong, Yeong Seok;Kim, Hyeon Muk
    • Journal of the Korean Chemical Society
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    • v.38 no.10
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    • pp.753-762
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    • 1994
  • Dephosphorylation of diphenyl- or isopropylphenyl-4-nitrophenylphosphinate (DPNPIN or IPNPIN) mediated by $OH^-$ or o-iodosobenzoate ion ($IB^-$) are relatively slow in aqueous solution. The reactions in CTAX micellar solutions are, however, very accelerated, because CTAX micelles can accommodate both reactants in their Stern layer in which they can easily react, while hydrophilic $OH^-$(or $IB^-$) and hydrophobic phosphinates are not mixed in water. Even though the concentrations (> $10^{-3}$ M) of $OH^-$(or $IB^-$) in CTAX solutions are much larger amounts than those ($6{\times}10^{-6}$ M) of phosphinates, the rate constants of the dephosphorylations are largely influenced by change of the concentration of the ions, which means that the reactions are not followed by the pseudo first order kinetics. In comparison to effect of the counter ions of CTAX in the reactions, CTACl is more effective on the dephosphorylation of DPNPIN (or IPNPIN) than CTABr due to easier expelling of $Cl^-$ ion by $OH^-$(or $IB^-$) ion from the micelle, because of easier solvation $Cl^-$ ion by water molecules. The reactivity of IPNPIN with $OH^-$(or $IB^-$) is lower than that of DPNPIN. The reason seems that the 'bulky' isopropyl group of IPNPIN hinders the attack of the nucleophiles. The mechanism of reaction of IPNPIN with IB- ion concluded as 'nucleophilic' instead of 'general basic' by a trapping experiment and a measured kinetic isotope effect.

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Effect of Fermented Garlic Extract on Adhesion of THP-1 Cells to Bovine Aortic Endothelial Cells (혈관내피세포에 부착하는 THP-1에 대한 발효마늘추출물의 효과)

  • Kwon, Ohseong;Song, Jina;Yu, Heui Jong;Park, Heonyong
    • Journal of Life Science
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    • v.27 no.5
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    • pp.553-560
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    • 2017
  • Fermented garlic extract (FGE) is a well-known functional food containing cycloalliin. Here we tested if FGE has an effect on the vascular system. We found that FGE had an effect on monocytic adhesion to endothelial cells, which occurs at the initial step of processes of inflammation. From dose-dependent experiments, 0.1 to $1{\mu}g/ml$ of FGE appeared to inhibit lipopolysaccharide (LPS)-enhanced heterotypic cell adhesion between THP-1 and BAECs. This result indicates that FGE blocks vascular inflammation. Then we found that FGE activates eNOS and Akt in BAECs. The phosphorylation of eNOS was maximally elevated 10 min after FGE treatment. Parallely, the phosphorylation of Akt was also maximally increased 10 min after FGE treatment. Consistently, it was found that FGE enhanced the production of nitric oxide. We then examined whether NO mediates THP-1 cell adhesion to BAECs. Both Akt and eNOS inhibitors appeared to reverse an inhibitory effect of FGE. These findings indicate that FGE inhibits LPS-enhanced heterotypic cell adhesion via Akt and eNOS. In conclusion, FGE plays an important role in prevention of inflammatory diseases.

Influences of Divalent Cations and Membrane Phosphorylation Inhibitors on $Na^+-Ca^{++}$ Exchange in Synaptosomes (이가 양이온과 세포막 인산화 반응의 억제제가 Synaptosome에서의 소듐-칼슘 교환이동에 미치는 영향)

  • Shin, Yong-Kyoo;Lee, Chung-Soo;Lee, Kwang-Soo
    • The Korean Journal of Pharmacology
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    • v.24 no.2
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    • pp.179-187
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    • 1988
  • Verapamil, tetrodotoxin and tetraethylammonium chloride in the stated amount did not affect the $Na^{++}$ induced $Ca^{++}$ release. $Cd^{++}$ and $Zn^{++}$ significantly inhibited the $Na^{++}$ induced $Ca^{++}$ release. $Mn^{++}$ also inhibited $Na^+-Ca^{++}$ exchange. $Cd^{++}$ inhibited $Na^+-Ca^{++}$ exchange noncompetitively with an apparent inhibition constant (Ki) of $100\;{\mu}M$. $Cd^{++}$ caused loss of sulfhydryl group, whereas $Zn^{++}$ did not show any significant effect. $Cd^{++}$ and $Zn^{++}$ effectively inhibited $Na^+-Ca^{++}$ ATPase and slightly inhibited $Ca^{++}-Mg^{++}$ ATPase. Carbonyl cyanide chlorophenylhydrazone, 2,4-dinitrophenol and sodium arsenate stimulated the $Na^{++}$ induced $Ca^{++}$ release. Dibucaine and oligomycin slightly inhibited it. The results suggest that the $Na^+-Ca^{++}$ exchange on the synaptosomal plasma membrane may be not accomplished by ion channels. The $Na^+-Ca^{++}$ exchange is sensitively inhibited by $Cd^{++}$ and this transport process appears to be partially regulated by sulfhydryl groups of the synaptosomal plasma membrane. It is also postulated that $Na^+-Ca^{++}$ exchange is suppressed during the phosphorylation reaction of protein component on the neuronal membrane.

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Inhibitory Effect of Semen Sinapis Albae on Immediate Hypersensitivity Reaction (백개자의 즉시형 과민 반응에 대한 억제 효과)

  • Lee, Kyou-Young;Hong, Chul-Hee
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.27 no.4
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    • pp.177-188
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    • 2014
  • 목적 : 본 연구에서는 백개자 열수추출물이 활성화된 대식세포 및 사람 비만세포주, HMC-1에서 염증 반응을 효과적으로 억제하는가를 관찰하고자 하였다. 방법 : 대식세포에 여러 농도의 백개자 열수추출물을 가한 뒤 LPS로 염증을 유도하여 NO 생산, iNOS와 COX-2 단백질 발현을 관찰하였으며 HMC-1에도 여러 농도의 백개자 열수추출물을 가한 후 PMACI로 염증을 유도하여 histamine 분비와 NF-${\kappa}B$ 활성 및 $I{\kappa}B$-${\alpha}$의 인산화, MAPKs pathway에 대한 저해효과를 관찰하였다. 결과 : 백개자 열수추출물은 대식세포에서 LPS로 유도된 NO 생성 및 INOS, COX-2 단백질 발현을 농도 의존적으로 저해하였으며 HMC-1에서 PMACI로 유도된 histamine의 분비와 p38 MAPK, ERK, JNK의 인산화 반응 및 $I{\kappa}B$-${\alpha}$의 인산화와 NF-${\kappa}B$의 활성을 저해하였다. 결론 : 백개자 열수추출물은 대식세포 및 비만세포의 활성을 저해함으로써 알레르기 질환의 치료에 사용될 잠재성이 크다고 사료된다.

Dephosphorylation of Diphenyl-4-Nitrophenyl Phosphinate(DPNPIN) onto 2-Alkylbenzimidazolide Anion in TTABr Micellar Solution (TTABr 미셀 용액속에서 2-알킬벤즈이미다졸 음이온에 의해 추진되는 디페닐-4-니트로페닐 포스페네이트(DPNPIN)의 탈인산화반응)

  • Kim, Jeung-Bea
    • Journal of Environmental Science International
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    • v.24 no.8
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    • pp.981-992
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    • 2015
  • This study is mainly focused on micellar effect of tetradecyltrimethyl ammonium bromide(TTABr) solution including alkylbenzimidazole(R-BI) on dephosphorylation of diphenyl-4-nitrophenylphosphinate(DPNPIN) in carbonate buffer(pH 10.7). Dephosphorylation of DPNPIN is accelerated by $BI^{\Theta}$ ion in $10^2$ M Carbonate buffer(pH 10.7) of $4{\times}10^{-4}$ M TTABr solution up to 80 times as compared with the reaction in Carbonate buffer by no benzimidazole(BI) solution of TTABr. The value of pseudo first order rate constant($k_{\psi}$) of the reaction in TTABr solution reached a maximum rate constant increasing micelle concentration. The reaction mediated by $R-BI^{\Theta}$ in micellar solutions are obviously slower than those by $BI^{\Theta}$, and the reaction rate were decreased with increase of lengths of alkyl groups. It seems due to steric effect of alkyl groups of $R-BI^{\Theta}$ in Stern layer of micellar solution. The surfactant reagent, TTABr, strongly catalyzes the reaction of DPNPIN with R-BI and its anion($R-BI^{\Theta}$) in Carbonate buffer(pH 10.7). For example, $4{\times}10^{-4}$ M TTABr in $1{\times}10^{-4}$ M BI solution increase the rate constant($k_{\psi}=99.7{\times}10^{-4}1/sec$) of the dephosphorylation by a factor ca. 28, when compared with reaction($k_{\psi}=3.5{\times}10^{-4}1/sec$) in BI solution(without TTABr). And no TTABr solution, in BI solution increase the rate constant($k_{\psi}=3.5{\times}10^{-4}1/sec$) of the dephosphorylation by a factor ca. 39, when compared with reaction ($k_{\psi}=1.0{\times}10^{-5}1/sec$) in water solution(without BI).

Dephosphorylation of an Organic Phosphinate by Nucleophile in Anionic and Cationic Micellar Solutions (음이온 및 양이온 미셀 용액에서 친핵체에 의한 유기 포스피네이트의 탈인산화반응)

  • Kim, Jeung-Bea
    • Journal of Environmental Science International
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    • v.15 no.5
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    • pp.485-491
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    • 2006
  • In the aqueous solutions the dephosphorylations of isopropyl phenyl-4-nitrophenyl phosphinate(IPNPIN) mediated by hydroxide$(OH^{\theta})$ and o-iodosobenzoate$(IB^{\theta})$ ions ate relatively slow, because of hydrophobicity of the substrate, and however it appears that $OH^{\theta}$ is inherently better nucleophile than $IB^{\theta}$, which is more soft ion. On the other hand, in cetyltrimetyiammonium bromide(CTABr) solutions which contain cationic micelles, the dephosphorylations of IPNPIN mediated by $OH^{\theta}$ or $IB^{\theta}$ ate very accelerated to 120 or 100,000 times as compared with those in the aqueous solutions. The values of pseudo first order rate constants reach a maximum with increasing. Such rate maxima are typical of micellar catalysed bimolecular reactions and the rise in rate constant followed by a gradual decrese is characteristic of reactions of hydrophobic substrates. In the cationic micellar solutions of CTABr, $IB^{\theta}$ accelerates the reactions much more than that $OH^{\theta}$ does. The reason seems that $IB^{\theta}$ which is more hydrophobic and soft ion than $OH^{\theta}$ is more easily moved into the Stern layer of the CTABr micelles than $OH^{\theta}$. In the anionic micellar solutions of sodium dodecyl sulfate(SDS), the dephosrhorylations of IPNPIN ate slower than those in aqeous solutions. It means that $OH^{\theta}$ or $IB^{\theta}$ cannot easily move and approach to the Stern layer of the micelle in which almost all the hydrophobic substrate are located and which has a negative circumstance.

Phosphorylation of silk fibroin and its properties (견 피브로인의 인산화와 그 특성)

  • 문장희;김정호;배도규;신봉섭
    • Journal of Sericultural and Entomological Science
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    • v.43 no.2
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    • pp.116-124
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    • 2001
  • To improve the functional properties as a food, silk fibroin was phosphorylated with STMP In the phosphorylation reaction of silk fibroin, the degree of phosphorylation was increased with high alkali index and treatment temperature. Depending on treatment time and concentration of STMP it was rapidly increased up to 1hr. and 50%, but slowly above that time and 100%. It was indicated in the results of FT-IR analysis and $\^$31/p NMR spectroscopy of phosphorylated fibroin that it had a close ∝-helix and poly-phosphate structure. The more phosphorylation of fibroin made more turbidity, foam expansion and foam stability, but less solubility. Emulsifying activity was increased up to P100, but slightly decreased above Pl00 and emulsifying stability was constantly increased on the progressing of phosphorylation.

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Preparation of Polypropylene Fabric Adsorbent Containing Phosphoric Acid by Radiation-Induced Graft Copolymerization, and Adsorption of $Cu^{2+}$, $Pb^{2+}$ and $Co^{2+}$ (방사선 그라프트 공중합에 의한 인산기를 갖은 폴리프로필렌 부직포 흡착제의 제조 및 구리, 납, 및 코발트 이온의 흡착)

  • Park, Keun-Su;Chang, Choo-Hwan;Kim, Hak-Jin;Choi, Seong-Ho;Nho, Young Chang
    • Analytical Science and Technology
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    • v.12 no.1
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    • pp.7-12
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    • 1999
  • The cation-exchange adsorbent (CEA) was prepared by radiation-induced grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) fabric and its subsequently phosphonation. The adsorption characteristics of $Pb^{2+}$, $Cu^{2+}$ and $Co^{2+}$ for the CEA were discussed. In the grafting of GMA onto PP fabric, the degree of grafting (%) increased with increasing reaction time, reaction temperature, and pre-irradiation dose. The maximum grafting yield was observed around 60% GMA concentration. The content of phosphoric acid ranges from 2.5 to 3.5 mmol/g with the 85% phosphoric acid. The adsorption of $Pb^{2+}$, $Cu^{2+}$ and $Co^{2+}$ by the CEA was enhanced with increasing phosphoric acid content. The order of adsorption capacity of CEA was $Pb^{2+}$>$Co^{2+}$>$Cu^{2+}$.

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Dephosphorylation Study of Phosphorylated Myelin Basic Protein: A Model Substrate for Protein Phosphatase (인산화된 신경수초 염기성 단백질의 탈인산화 연구: 단백질 탈인산화 효소의 기질 모델)

  • Kim, Jin Hahn;Choi, Myung Un
    • Journal of the Korean Chemical Society
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    • v.41 no.4
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    • pp.205-209
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    • 1997
  • The site specificity of dephosphorylation of myelin basic protein(MBP) was studied in vitro. To assign amino acid site of dephosphorylation, MBP was phosphorylated by protein kinase C(PKC) and dephosphorylated by protein phosphatase PP2A. The phosphorylated MBP was digested by trypsine and the digested peptides were separated by a reverse phase HPLC chromatography. The radioactivity of each fraction was counted and partially sequenced. Seven radioactive peptides were observed and $Ser^{55}$ in the second peak($P_2$) shows the best susceptibility for the phosphorylation. However in the dephosphorylation, the fifth peak($P_5$) appeared to release it's phosphate group most rapidly. This result demonstrates that MBP is a suitable substrate for protein phosphatase.

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