Alkaline Phosphatase from Rat Uterus: Purification and Characterization

양범석,양철학,Yang, Beom-Seok,Yang, Chul-Hak 생화학분자생물학회 1985 한국생화학회지 Vol.18 No.1

알카리성 포스파타아제를 쥐의 자궁으로부터 부탄올 추출, 아세톤 침전법, 세파텍스 G-200을 이용한 젤 크로마터그래피법, 콘카나발린 A를 이용한 흡착 크로마토그래피법, 그리고 등전초점화법을 이용하여 정제하였다. 이 효소의 분자량은 560,000달톤이었고 pH 6 이하에서는 매우 불안정하나 pH8-9 사이에서는 가장 안정하였다. 열에 대한 안정도로 비교할 때 쥐 자궁의 알카리성 포스파타아제는 태반의 알카리성 포스파타아제와는 다른 효소였다. 효소활동도의 최적 pH는 기질의 농도가 증가 함에 따라 증가한다. 즉 10배의 기질 농도 증가에 대해 최적 pH는 0.62씩 증가한다. 반응용액의 이온강도는 효소 활동도에 영향을 미친다. 즉 이온강도가 증가함에 따라 $K_m$값은 감소하고 $V_{max}$는 증가한다. log $V_{max}$는 이온강도의 제곱근에 비례하는데 이것은 E-S 복합체에서 생성물로 가는 반응경로에 이온반응이 있음을 암시한다. 이 효소의 등전점은 pH 6.5-7.1사이에 넓게 분포하며 pH 6.8이 주둥전점이다. 이 효소는 $Mg^{2+}$ 이온에 의해 그 활동도가 크게 증가되나 효소활동도의 최적 pH는 서로 일치하지 않는다. 이 효소는 DEAE리간드에 강하게 부착되는데 이는 일반적인 단백질과 리간드 사이의 정전기적 인력에 의한 결합이 아니기 때문에 매우 높은 이온강도를 가지는 완충용액으로서도 리간드와 단백질을 분리할 수 없으며 단지 2-아미노-2-메칠-1, 3-프로판디올 1 M 용액으로 이 효소를 DEAE 리간드로 부터 분리할 수 있다. Alkaline phoshatase (orthophosphoric monoester phosphohydrolase EC 3.1.3.1) which hydrolyzes a variety of monophosphate esters was purified from rat uterus, using butanol extraction, acetone precipitation, gel filtration on Sephadex G-150, affinity chromatography on Concanavalin A-Sepharose 4B, and isoelectric focusing. This enzyme has the molecular weight of 560,000 daltons by gel filtration and it is very unstable below pH 6.0 and the most stable between pH 8-9. This enzyme shows pH optimum shift of 0.62 pH with 10-fold increase in substrate concentration. Ionic strength in the reaction buffer affects the enzyme activity that is, increase in ionic strength decreases $K_m$ and increases the $V_{max}$. The log $V_{max}$ is primarily dependent on the square root of ionic strength. From the thermostability study, it may be concluded that alkaline phosphatase from rat uterus is a different isoenzyme from that of other rat tissues like placenta, liver, and intestine. Among divalent cation, $Mg^{2+}$ is a good activator for the enzyme and $Ca^{2+}$ shows an activation only when its concentration is more than 100 mM. The optimum pH of enzyme activation by $Mg^{2+}$ does not coincide with the optimum pH of enzyme activity. This enzyme has a multiple pI values of pI 6.5-7.1 from the isoelectric forcusing. This enzyme strongly binds to DEAE-Sephadex not by the normal charge to charge interaction but by an uncertain interaction between the enzyme and DEAE-ligand. The bound enzyme activity is not eluted even with the high ionic strength buffer containing 1.2 M NaCl. But it can be eluted by the 1 M solution of 2-amino-2-methyl-1, 3-propanediol.

쥐의 자궁에서 알카리성 포스파타아제의 분리 및 그 효소의 특성에 관한 연구

양범석,양철학 ( Beom Seok Yang,Chul Hak Yang ) 생화학분자생물학회 1985 BMB Reports Vol.18 No.1

Alkaline phoshatase (orthophosphoric monoester phosphohydrolase EC 3.1.3.1) which hydrolyzes a variety of monophosphate esters was purified from rat uterus, using butanol extraction, acetone precipitation, gel filtration on Sephadex G-150, affinity chromatography on Concanavalin A-Sepharose 4B, and isoelectric focusing. This enzyme has the molecular weight of 560,000 daltons by gel filtration and it is very unstable below pH 6.0 and the most stable between pH 8-9. This enzyme shows pH optimum shift of 0.62 pH with 10-fold increase in substrate concentration. Ionic strength in the reaction buffer affects the enzyme activity that is, increase in ionic strength decreases Km and increases the V_(max). The log V_(max) is primarily dependent on the square root of ionic strength. From the thermostability study, it may be concluded that alkaline phosphatase from rat uterus is a different isoenzyme from that of other rat tissues like placenta, liver, and intestine. Among divalent cation, Mg^(2+) is a good activator for the enzyme and Ca^(2+) shows an activation only when its concentration is more than 100 mM. The optimum pH of enzyme activation by Mg^(2+) does not coincide with the optimum pH of enzyme activity. This enzyme has a multiple pI values of pI 6.5-7.1 from the isoelectric forcusing. This enzyme strongly binds to DEAE-Sephadex not by the normal charge to charge interaction but by an uncertain interaction between the enzyme and DEAE-ligand. The bound enzyme activity is not eluted even with the high ionic strength buffer containing 1.2 M NaCl. But it can be eluted by the 1 M solution of 2-amino-2-methyl-1, 3-propanediol.

자전연소반응법에 의해 제조된 PZT의 전기적 특성에 미치는 Sr의 영향

양범석,신창윤,원창환,Yang, Beom-Seok,Shin, Chang-Yun,Won, Chang-Whan 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.11

PSZT are selected and SHS are applied to each system. The sintering properties of PSZT powders showed $7.754g/cm^3$ of sintered density and $4{\mu}m$ of grain size at sintering temperature of $1250^{\circ}C$. Curie temperature lowered gradually from $363.6^{\circ}C\;to\;319.2^{\circ}C$ and relative dielectric constants increased rapidly by a quantity of Sr. This remarkable contrast in dielectric properties with powder preparation methods, in this study, was not due to grain size and sintered density but rather a crystallinity and sinterability of synthesized powders, extra-supplied Pb during reaction, mol fraction of rhombohedral phase and purity of starting materials.

수열합성법으로 제조된 PZT 분말의 특성

양범석,이혁희,원창환,Yang, Beom-Seok,Lee, Huk-Hee,Won, Chang-Whan 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.7

Conditions for formation of perovskite Pb(Zr$_{0.52}$Ti$_{0.48}$)O$_{3}$ phase by the hydrothermal synthesis are investigated. Pb(Zr$_{0.52}$ Ti$_{0.48}$)O$_{3}$ ceramics were synthesized by hydrothermal process above 180$^{\circ}C$ for 2 h reaction using 5$\~$30 M KOH solution as a mineralizer. Particle size increases in proportion to the mineralizer concentration. As a result of EOX analysis, PZT powders synthesized using 50 M of KOH as a mineralizer were considered as 2.42 mol$\%$ K doped-PZT powders. And 2.42 mol$\%$ K doped-PZT has much higher mechanical quality factor than undoped PZT ceramics. The sintering properties showed 7.987 g/cm$^{3}$ of sintered density and 3$\~$4 $\mu$m of grain size.

수열합성법으로 제조된 PZT 분말의 특성에 미치는 광화제 농도와 출발물질의 영향

양범석,윤기석,박영철,원창환,Yang, Beom-Seok,Yun, Ki-Seok,Park, Young-Chul,Won, Chang-Whan 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.11

The effect of reaction parameters in the characteristic of $Pb(Zr_{0.52} Ti_{0.48})O_3$ powders by hydrothermal process was investigated in this study. In the preparation of PZT, the types of starting material and concentration of mineralizer on phase fraction and morphology was investigated respectively. Regardless the types of Pb precursor, PZT was able to synthesize ranging from 7 to 20 on KOH concentration and from 13.01 to 13.55 on pH of solution. The particle size of the PZT powders can be controlled by the mineralizer concentration and various types of precursor.

Gene Expression Regulation by ras Signaling : Signaling from ras to ets

양범석 ( Beom Seok Yang ) 생화학분자생물학회 1997 생화학분자생물학회 춘계학술발표논문집 Vol.- No.-

SHS법을 이용한 복합분말(Al₂O₃-SiC) 제조시 TiO₂첨가의 영향

윤기석,양범석,이종현,원창환,Yun, Gi-Seok,Yang, Beom-Seok,Lee, Jong-Hyeon,Won, Chang-Hwan 한국재료학회 2002 한국재료학회지 Vol.12 No.1

$Al_2O_3-SiC$ and $Al_2O_3-SiC$-TiC composite powders were prepared by SHS process using $SiO_2,\;TiO_2$, Al and C as raw materials. Aluminum powder was used as reducing agent of $SiO_2,\;TiO_2$ and activated charcoal was used as carbon source. In the preparations of $Al_2O_3-SiC$, the effect of the molar ratio in raw materials, compaction pressure, preheating temperature and atmosphere were investigated. The most important variable affecting the synthesis of $Al_2O_3-SiC$ was the molar ratio of carbon. Unreactants remained in the product among all conditions without compaction. The optimum condition in this reaction was $SiO_2$: Al: C=3: 5: 5.5, 80MPa compaction pressure under Preheating of $400^{\circ}C$ with Ar atmosphere. However there remains cabon in the optimum condition. The effect of $TiO_2$ as additive was investigated in the preparations of $Al_2O_3-SiC$. As a result of $TiO_2$ addition, $Al_2O_3-SiC$-TiC composite powder was prepared. The $Al_2O_3$ powder showed an angular type with 8 to $15{\mu}m$, and the particle size of SiC powder were 5~$10{\mu}m$ and TiC powder were 2 to $5{\mu}m$.

용융염계에서 자전연소합성법에 의한 α-Si₃N₄ 분말의 제조 (Part 3. 반응기구)

윤기석,양범석,박영철,원창환,Yun, Ki-Seok,Yang, Beom-Seok,Park, Young-Cheol,Won, Chang-Whan 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.12

SHS법으로 합성된 PZT분말의 특성에 미치는 반응변수의 영향

김병범,양범석,윤기석,원창환,Kim, Byeong-Beom,Yang, Beom-Seok,Yun, Ki-Seok,Won, Chang-Whan 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.5

The effect of reaction parameters in the characteristic of $Pb(Zr_{0.52}Ti_{0.48})O_3$ (below nominal PZT) powders by SHS was investigated in this study. In the preparation of PZT, the effect of starting material contents, pressure, additive on phase fraction and morphology was investigated respectively. The optimum condition of PZT powders were prepared by SHS is $0.37Pb_3O_4+0.52ZrO_2+0.48TiO_2+0.35KClO_3+0.5C,\;(P_{Ar}= 50 atm)$. The PZT powder synthesized in this condition had an spherical shape and the particle size of 0.8$\mu$m.

용융염계에서 자전연소합성법에 의한 α-Si₃N₄분말의 제조 - 2. 반응물의 증가

윤기석,양범석,박영철,원창환,Yun Ki Seok,Yang Beom Seok,Park Young Cheol,Won Cang Whan 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.9

The variation of the reaction pressure and reaction product during the reaction was investigated according to the total mass of the reaction mixture at the optimum composition for the preparation of u-Si3N4 powder which had been confirmed in the former investigation; 'Preparation of $\alpha$-Si$_3$N$_4$ powder in reaction system containing molten salt by SHS - part 1. synthesizing of powder'. When the total mass of the reaction mixture was 100g, the minimum pressure for a complete reaction was 60atm in 5L reactor, whereas the reaction was incomplete in the case that the mass exceeded 200g because of pressure increase. Also, as the mass of the reaction mixture increased, the reactivity linearly decreased. Hence, the complete reaction was realized by decreasing an initial $N_2$ pressure, and thus obtained minimum initial pressure was recorded 20 atm for the initial mixture of 500g. The reason of the incomplete reaction with pressure Increase was found to be that NH$_4$Cl vapour which was suppressed by the gas pressure acted as a diluent. 앞선 논문 분말의 제조에서 정립한 $\alpha$-Si$_3$N$_4$ 분말의 제조를 위한 최적의 조성에서 반응 혼합물의 양에 따른 압력 및 생성물의 변화를 관찰하였다. 5L 반응기 내에서 반응 혼합물의 양이 100g일 때 필요한 최저 $N_2$ 압력은 60atm이었다. 그러나 반응 혼합물의 양이 200g 이상일 때부터 반응기 내부의 압력 증가로 인해 반응은 완료될 수 없었으며, 혼합물이 증가할수록 반응율은 직선적으로 감소하였다. 반응물의 양이 증가할수록 최초 반응기 내부의 $N_2$압력을 감소시킴으로써 반응을 완료시킬 수 있었으며, 500g일 때 초기 $N_2$ 압력을 약 20atm까지 감소시킴으로써 반응은 완료될 수 있었다. 반응이 중간에 멈추는 원인은 반응기 내부의 압력 증가로 인해 기화되지 못한 채 혼합물 안에 존재한 NH$_4$Cl때문인 것으로 밝혀졌다.