• 제목/요약/키워드: $K^+$-ATPase

검색결과 663건 처리시간 0.031초

이스라엘 잉어 Actomyosin의 열안정성과 그 보호 (Thermal Stability of Israeli Carp Actomyosin and Its Protection by Chemical Additives)

  • 남택정;최영준;변재형
    • 한국수산과학회지
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    • 제17권4호
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    • pp.271-279
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    • 1984
  • 이스라엘 잉어의 근육 actomyosin의 열안정성과 그 첨가제에 의한 영향을 밝히기 위하여 배육골격근에서 추출한 actomyosin을 시료로 하여 온도의 변화가 actomyosin의 안정성에 미치는 영향을 ATP-감도, 유리 SH기 및 Ca-ATPase 활성도 등을 측정하여 분석하였다. 그리고 sucrose, sorbitol, Na-glutamate 및 L-cysteine등 첨가제의 영향에 대하여는 Ca-ATPase 활성도의 변화를 측정하여 단백질 변성속도당수($K_D$), 단백질변성보호효과(${\Delta}E/M$) 그밖에 열력학적 제상수를 계산 비교하였다. 실험결과를 요약하면 다음과 같다. 1. 배육골격근에서 추출한 이스라엘 잉어 actomyosin은 단백질농도 $4.12{\sim}4.68mg/ml$, 핵산의 함량 $2.63{\sim}2.9%$, actin과 myosin의 결합비 $1:2.20{\sim}2.63$, 지질의 함량 $4.33{\sim}5.26\%$, ATP-감도 109.78, Ca-ATPase 활성 $0.159{\sim}0.201\;{\mu}M-Pi/min/mg-protein$, 유리 SH 기 함량 $3.3{\sim}3.4M/10^5g-protein$ 이었다. 2. Ca-ATPase활성 및 ATP-감도는 온도가 상승 함에 따라 1차반응적으로 감소하였고, 유리 SH기는 $60{\circ}C$ 까지는 증가하다가 그 이후는 급격히 하강하였다. 3. 가열온도상승에 따른 Ca-ATPase 활성의 반감 시간은 $12^{\circ}C$ 일때 280분, $20^{\circ}C$ 일 때 125분, $30^{\circ}C$일때 55분, $40^{\circ}C$ 일때 13분이었으며 $20^{\circ}C$에서 활성화에너지는 5,395 cal/mole 활성화엔탈피는 4,814cal/mole, 활성화엔트로피는 -40.42 e.u, 자유에너지 값은 17,626cal/mole이었다. 4. 당 및 아미노산중에서 가열에 대하여 변성보호효과가 높은 것은 $3\%$ sorbitol이었으며, $8\%$ Na-glutamate, $1\%$ sucrose, $1\%$ L-cysteine의 순으로 낮아졌다. 5. 저온저장시 actomyosin이 가장 안정한 온도는 $-30^{\circ}C$이었으며, $0^{\circ}C,\;-20^{\circ}C$ 순으로 불안정하였다. 또한 $-20^{\circ}C$ 일 때의 첨가제에 의한 냉동변성보호효과는 $8\%$ Na-glutamate가 가장 좋았고 $3\%$ sorbitol, $1\%$ sucrose, $1\%$ L-cysteine의 순으로 효과가 떨어졌다.

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Diabetic Alterations in Cardiac Sarcoplasmic Reticulum $Ca^{2+}$-ATPase and Phospholamban Protein Expression

  • Lee, Hee-Ran;Cho, Yong-Sun;Park, So-Young;Kim, Young-Hoon;Kim, Hae-Won
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
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    • pp.66-66
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    • 2001
  • Diabetic cardiomyopathy has been suggested to be caused by abnormal intracellular $Ca^{2+}$ homeostasis in the myocardium, which is partly due to a defect in calcium transport by the cardiac sarcoplasmic reticulum (SR). In the present study, the underlying mechanism for this functional derangement was investigated with respect to SR $Ca^{2+}$-ATPase and phospholamban (PLB, the inhibitor of SR $Ca^{2+}$-ATPase).(omitted)d)

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Studies on the Membrane Topology of the (Na, K) ATPase

  • Lee, Kyunglim-Yoon
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 춘계학술대회
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    • pp.181-181
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    • 1996
  • The (Na, K) ATPase is a membrane ion transporting ATPase composed of an ${\alpha}$ catalytic subunit and a ${\beta}$ glycoprotein subunit. The topology of the rat ${\alpha}$1 and ${\beta}$1 subunits has been studied by insertion of epitope(s) : at the NH2-terminus and COOH-terminus and between Glu117 and Glul18, Lys828 and Arg829, Gln900 and Trp901, and Va1939 and Phe940 of the ${\alpha}$ subunit; and at the NH2-terminus and COOH-terminus and between Glu228 and Tyr229 of the ${\beta}$ subunit. The epitope-tagged ${\alpha}$l, constructs were expressed in HeLa cells to select for stable cell lines expressing a functional (Na, K)ATPase. All constructs, except for the one tagged between Gln900 and Trp901, resulted in ouabain-resistant colonies indicating that modified proteins retained functional integrity. The epitope-tagged ${\beta}$ constructs were transiently expressed in Cos-7 cells. The orientation of the epitopes with respect to the cell membrane was revealed by indirect immunofluorescence performed on permeabilized and non-permeabilized cells expressing the (Na, K)ATPase chains. The results indicate that the ${\alpha}$ subunit has 4 transmembrane segments in the COOH terminal membrane bound domain between residues 760 and 938, and that both the NH2-terminus and the COOH-terminus are in the cytosol; it was not determined whether there are more transmembrane segments between residue 938 and the COOH-terminus. The ${\beta}$ subunit has only one transmembrane spanning region with the NH2-terminus in the cytosol and the COOH-terminus on the extracytoplasmic surface of the plasma membrane.

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염스트레스가 담배식물의 Protein, ATPase 및 Peroxidase 활성에 미치는 영향 (Effects of Salt Stress on Protein Content, ATPase and Peroxidase Activities in Tobacco.)

  • 이상각;강병화;이학수;배길관
    • 한국환경농학회지
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    • 제17권4호
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    • pp.296-300
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    • 1998
  • 본 실험은 담배에서 염스트레스에 따른 생리적 반응의 연구결과(제1보)를 기초로, NaCl를 농도별로 처리하여 생체내에서 일어나는 생화학적인 변화의 구명을 통해 염해기작의 기초자료로 얻고자 수행한 결과를 요약하면 다음과 같다. 총단백질과 가용성단백질은 염농도가 높아질수록 감소하였으며 처리간에는 120mM까지는 완만히 감소하였고, 150mM에서는 급격한 감소를 나타냈다. 전기영동 패턴은 염농도의 증가에 따라 새로운 polypeptide band의 생성과 소멸은 없었으며 약 74Kd의 polypeptide band에서 30mM과 60mM까지는 뚜렷한 양이 증가하였고 90mM부터는 감소하였다. 엽록소함량은 염농도의 증가에 따라 감소하였으며 특히 염해에 의한 반응은 엽록소b보다는 엽록소a가 민감하였다. ATPase활성과 peroxidase의 활성은 염농도가 높아질수록 120mM까지는 일정하게 증가하였으나 150mM에서 급격히 증가하여 담배의 염해의 생화학적인 제한범위는 120mM로 나타났다.

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Effect of Omeprazole on Membrane P-Type ATPase and Peptide Transport in Helicobacter pylori

  • KI, MI-RAN;SOON-KYU YUN;SE-YOUNG HWANG
    • Journal of Microbiology and Biotechnology
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    • 제9권3호
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    • pp.235-242
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    • 1999
  • We investigated the growth-inhibitory mechanism of Helicobacter pylori by omeprazole (OMP) and its activated sulfenamide (OAS). Using dithiothreitol (DTT) and 5,5'-dithio-bis[2-nitrobenzoic acid] (DTNB; Ellman's reagent), we first determined the relationship between the binding capacity of these compounds to H. pylori membrane and its significance to membrane P-type ATPase activity. After incubation of the intact H. pylori cells with either OMP or OAS, the residual quantity of free SH-groups on the cell membrane was measured, and, the resulting values were plotted as a function of time. From this experiment, we found that there was a considerable difference in the membrane-binding rates between OMP and OAS. At neutral pH, the disulfide bond formation on H. pylori membrane was completed within 2 min of incubation of the intact cells with OAS. By OMP, however, it was gradually formed, exceeding 10 min of incubation for completion, whereby, the extent of P-type ATPase inhibition appeared to be proportional to the disulfide forming rate. From this data, it was suggested that the disulfide formation might directly affect enzyme activity. Since OMP per se cannot yield a disulfide bond with cysteine, it is predicted that the enzyme inactivation must be caused by the OAS form. Accordingly, we postulated that, under the neutral pH, OMP could be converted to OAS in the course of transport. By extrapolating the inhibitory slopes, we could evaluate K₁ values, relating to their minimal inhibitory concentrations (MICs) for H. pylori growth. In these MIC ranges, H. pylori uptake or vesicular export of nutrients such as peptides were totally prohibited, but their effect in Escherichia coli were negligible. From these observations, we strongly suggest that the P-type ATPase activity is essential for the survival of H. pylori cells in particular.

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사궁산(莎芎散)이 실험동물(實驗動物)의 지혈(止血), 뇌압(腦壓), 혈압(血壓) 및 심혈관계(心血管系)에 미치는 영향(影響) (Effects of Sagungsan on the Hemostasis, Intracranial Pressure, Blood Pressure and Cardiovascular System in Expreimental Animals)

  • 안일회;박영순;김세길
    • 대한한방내과학회지
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    • 제15권1호
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    • pp.80-98
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    • 1994
  • According to the original documents, Sagungsan is considered as an effective drug for controlling the hypertensive epistaxis induced by tension of autonomic nerve and it's hyperfunction. The present experiment was designed to understand the effect of Sagungsan extract on the hemostatic action, intracranial pressure, blood pressure and cardiovascular system in experimental animals. And thus the bleeding time, prothrombin time, capillary dilation, blood pressure, Intracranial pressure, and enzymatic analysis of the ATPase activities were studied. The result obtained here were as followings: 1. Sagungsan water extract reduced the bleeding time in mouse, and prolonged the prothrombin time in rabbits. 2. The drug extract increased the tail volume by capillary dilation in rats. 3. The drug extract inhibited the increase of intracranial pressure and arterial blood pressure in rabbits. 4. At the early time, the increase of arterial blood pressure by the drug extract significantly inhibited by pretreated atropin and regitine in rabbits. 5. The drug extract relaxed the smooth muscle by stimulating the Mg2+-Ca2+-ATPase activities of gastric sarcoplasmic reticulum isolated from rabbit stomach. 6. The drug extract stimulated the heart contraction by inhibiting the $Mg^{2+}-Ca^{2+}-ATPase$ activities of cardiac sarcoplasmic reticulum isolated from rabbit heart. The inhibitory mechanism was reversible and noncompatitive. 7. The drug extract increased the hepatic blood volume by stimulating the hepatic total ATPase activities and hepatic metabolism. 8. The drug extract acted as a tranquilizer by inhibiting the neural Na+-K+-ATPase activity. According to the results, Sagungsan water extract dilated the capillaries, stimulated the heart beat, and thus increased the blood flow with decreasing the intracranial pressure and blood pressure. These effects stanches the epistaxis collectively.

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Effect of Dietary Fat on Hepatic Mitochondrial {TEX}$F_{1}${/TEX}{TEX}$F_{0}${/TEX}ATPase Characteristics in NIDDM-prone Rat

  • Kim, Sook-Bae B.;Kim, Chang-Im
    • Preventive Nutrition and Food Science
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    • 제5권4호
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    • pp.230-233
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    • 2000
  • The present work was designed to determine whether change in fluidity of the mitochondrial membrane affects mitochondrial {TEX}$F_{1}${/TEX}{TEX}$F_{0}${/TEX}ATPase characteristics in NIDDM-prone BHE/Cdb rat. Isolated mitochondria fom BHE/Cdb rat fed a 6% coconut oil or corn oil were functionally tested by an analysis of its respiration and the coupling of this process to ATP synthesis in presence of oligomycin, a specific inhibitor of oxidative phosphorylation (OXPHOS), that binds to the {TEX}$F_{1}${/TEX}{TEX}$F_{0}${/TEX}ATPase. Mitochondria from rats fed coconut oil were more responsive to the inhibitory action of oligomycin with respect to state 3 respiration, respiratory control (RC) ratio and ADP:P (P/O) ratio than were mitochondria from rats fed corn oil. In state 3 respiration, mitochondria from rats fed coconut oil consumed less oxygen than did mitochondria from rats fed corn oil. RC ratio was lower in the mitochondria from rats fed coconut oil than was mitochondria from rats fed corn oil. In P/O ratio, the mitochondria from rats fed coconut oil had a lower P/O ratio than did mitochondria from rats fed corn oil. The data showed that the chang influidity of the mitochondrial membrane by dietary fat affected mitochondrial {TEX}$F_{1}${/TEX}{TEX}$F_{0}${/TEX}ATPase characteristics. The present study on diet differences in {TEX}$F_{1}${/TEX}{TEX}$F_{0}${/TEX}ATPase characteristics provides considerable insight into the role diets play in the control of mitochondrial function, expecially OXPHOS in NIDDM with mitochondrial defects.

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Efficiency of ATP Synthesis and Impairment of Glucose Tolerance in the NIDDM-Prone Rat

  • Kim, Sook-Bae
    • Journal of Nutrition and Health
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    • 제30권4호
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    • pp.379-385
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    • 1997
  • This study was designed to determine whether genetic defects in the efficiency of ATP synthesis existed in the NIDDM-prone BHE/cdb rat and to determine whether these defects caused the development of glucose intolerance. Thyroxine treatment provided an excellent clue as to the nature of the genetic defects in this rat. The characteristics of hyperhyroid and control Sprague-Dawley(SD) and BHE/cdb rats were studied. Hyperthyroidism was induced through the addition of thyroxine($T_4$) to the diet(2mg/kg of diet). Active proton conductances and passive proton conductances were tested. Mitochondria from hyperhyroid BHE/cdb rats were less efficient iii active proton conductances than mitochondria from hyperhyroid SD rats. It showed that decreased efficiency of ATP synthesis in the BHE/cdb rat was probably related to defects in active proton conductance, Indicating aberrant FoATPase. The levels of $F_1F_0$ATPaseATPase activity were tested. Mitochondria from hyperthyroid BHE/cdb rats were less active than mitochondria from hyperthyroid SD rats. This may be an attribute of aberrant F$_1$ATPase and may contribute to the BHE/cdb strain s characteristic of reduced ATP synthesis efficiency. Glucose tolerances were tested. BHE/cdb rats were profoundly affected by thyroxine, whereas SD rats were less so. It showed that the diabetes phenotype in BHE/cdb rats was related to defects in thyroxine-induced uncoupling. These results showed the decreased efficiency of ATP synthesis due to genetic defects in $F_1F_0$ATPase had relevance to the characteristic of impaired glucose tolerance in the NIDDM-prone BHE/cdb rat.

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흰쥐 肝미토콘드리아의 非代謝依存性 칼슘 結合에 관한 연구 (Studies on the Metabolism-Independent Calium Binding of the Rat Liver Mitochondria)

  • Kang, Shin-Sung;Ha, Doo-Bong
    • 한국동물학회지
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    • 제13권3호
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    • pp.85-93
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    • 1970
  • 미토콘드리아의 Ca 결합은 물질대사에 의존하지 않는 初期 結合과 에너지 소비를 수반하는 膜透過의 二段階로 일어 난다는 설이 있다. 본 실험에서는 이를 확인키 위하여 흰쥐의 肝에 서 抽出한 미토콘드리아를 $^45 CaCl_2$를 함유한 sucrose-tris chloride 용액에서 incubate 시키면 서 Ca 흡수, 산소소비 및 ATPase 活性을 측정하였다. 미토콘드리아의 Ca 결합량은 온도의 영향을 거의 받지 않으며, succinate 나 ATP의 존재에 의해서도 증가하지 않는다. 반면 산소소비량은 succinate의 존재에 의하여 현저하게 증가되며 또 온도의 상승에 따라 증가된다. ATPase 活性도 온도의 상승에 따라 증가한다. 산소소비량과 Ca의 결합량이 비례하지 않는 것으로 보아 미토콘드리아의 Ca 초기 결합은 물질 대사에 의존하지 않는 것으로 판단된다. 미토콘드리아의 ATPase 活性은 DNP 의 존재에 의하여 증가된다.

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사람적혈구막에서의 Calcium과 Suramin의 상호작용 (Interaction of Calcium with Suramin in Human Red Cell Preparation)

  • 강복순;강두희
    • The Korean Journal of Physiology
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    • 제10권1호
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    • pp.1-5
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    • 1976
  • The trypanocidal drug suramin, an impermeant polyanion, has been shown to be a powerful inhibitor of the calcium uptake and calcium-stimulated ATPase activity of sarcoplasmic reticulum (Fortes et al., 1974). In view of this finding, an attempt was made to investigate the effect of suramin on $Ca^{++}$ transport in resealed red cells and on $Ca^{++}$-activated ATPase in red blood cell membrane fragments (RBCMF). The results obtained are summarized as follows. 1. $Ca^{++}$ outflux from the resealed RBC was inhibited by suramin and the inhibitory action of suramin is proportional to the concentration of drug added inside the RBC preparation. When suramin is added both inside and outside the RBC preparation simultaneously, the magnitude of the inhibitory effect was more pronounced, suggesting that suramin inhibits both active $Ca^{++}-^{45}Ca$ exchange diffusion across the RBC membrane. 2. Suramin inhibits the $Ca^{++}$-activated ATPase of the RBCMF and the effect of inhibition by the drug was also concentration dependent. From the above results, it may be concluded that suramin inhibits $Ca^{++}$ transport across RBC membrane by inhibiting $Ca^{++}$-activated ATPase activity which has been known to be linked with active $Ca^{++}$ transport.

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