• 제목/요약/키워드: $\Ca^{2+}$-ATPase

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토마토 뿌리조직에서 분리한 마이크로솜 이온펌프의 특성 (Characterization of Microsomal ATPases Prepared from Tomato Roots)

  • 조광현;사공정;김영기
    • Applied Biological Chemistry
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    • 제41권2호
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    • pp.130-136
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    • 1998
  • 토마토의 뿌리조직에 존재하는 여러 가지 이온이동 기작을 밝혀내기 위하여 뿌리조직으로부터 마이크로솜을 분리하였고, 마이크로솜에 존재하는 이온점프(ATPase)의 활성을 측정하였다. 원형질막과 액포막에 위치하는 $H^+-ATPase$들의 활성은 각각의 선택적 저해제인 vanadate와 $NO^-_3$를 이용하여 평가하였고, 이들의 활성은 각각 마이크로솜 ATPase 총활성의 ${\sim}30%$, ${\sim}38%$로 나타났다. 이들 두 가지 저해제 효과는 additive하게 나타났으며, 전체활성의 약 $50{\sim}70%$를 저해함을 확인하였다. 마이크로솜 ATPase활성은 pH의 영향을 받으며, 최대 활성은 pH 7.4에서 나타났다. ATPase 활성은 또한 10 mM 이상의 $K^+$에 의해서 약 30% 증가를 보였으며, $K^+$에 의한 활성촉진 효과는 $Na^+$에 의해서 완전히 저해되었다. $K^+$에 의한 ATPase 활성증가 기작을 조사하기 위해, 반응용액의 $K^+$농도를 조절하면서 선택적 저해제들의 효과를 측정하였다. 반응용액에 $K^+$이 없는 조건과 120mM $K^+$을 함유하는 조건에서 vanadate는 ATPase 활성을 동일하게 27% 저해하였으나, $NO^-_3$는 각각의 조건에서 32%, 40% 저해하였다. 이것은 $NO^-_3$에 민감한 액포막의 $H^+-ATPase$활성이 $K^+$에 의해서 촉진된다는 것을 시사한다. 마이크로솜 ATPase 활성은 $Ca^{2+}$에 의해서도 저해되었으며, $NO^-_3$$Ca^{2+}$에 의한 저해효과를 억제하였다. 이상의 결과는 토마토 뿌리조직의 마이크로솜 ATPase중 액포막의 $H^+-ATPase$ 활성이 $K^+$에 의해서 증가하며, $Ca^{2+}$에 의해서 저해되는 것을 보여준다.

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$Ca^{2+}-ATPase$ 3차원 결정의 Lamellar면 구조분석 (Structural Analysis of Lamellar Plane in Three-Dimensional Crystal of $Ca^{2+}-ATPase$)

  • 정강원
    • Applied Microscopy
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    • 제27권2호
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    • pp.111-120
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    • 1997
  • Cylinder-like crystals of $Ca^{2+}-ATPase$ provide views parallel to the lamellar plane, from which parameters of lamellar stacking can be directly measured. These parameters were measured using different preparation methods. Assuming that molecular packing is the same, data from lamellar plane could supplement those obtained by tilting large, thin plate-like crystals. However, base on data obtained .by electron microscopy and x-ray powder patterns, the plate-like crystal may have another scheme for stacking the lamellar. The projection map (h, 0, 1) from cylinder-like crystals using cryoelectron microscopy suggest the lamellar spacing can be variable.

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Benzyl Alcohol이 세포막의 형태 및 Calcium 이온 이동에 미치는 영향 (Effects of Benzyl Alcohol on Structures and Calcium Transport Function of Biological Cell Membranes)

  • 이황현;하종식;김구자
    • The Korean Journal of Physiology
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    • 제21권2호
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    • pp.157-167
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    • 1987
  • Benzyl alcohol is known to have dual effect on the red blood cell shape change. At low concentration up to 50 mM benzyl alcohol transformed the shape from discocyte to stomatocyte by preferent binding to the inner hemileaflet, however, at higher concentratransformed the shape from discocyte to stomatocyte by preferential binding to the inner monolayer, however, at higher concentration above 50 mM benzyl alcohol transformed to echinocyte by affecting both monolayers. These results suggest that the effect of benzyl alcohol on the red blood cell shape and $Ca^{++}$ transport across cardiac cell membranes to assess the effects of the drug on the structures and functions of the biological cell membranes. The results are as follows: 1) Benzyl alcohol up to 40 mM caused progressive stomatocytic shap change of the red blood cell but above 50 mM benzyl alcohol caused echinocytic shape change. 2) Benzyl alcohol up to 40 mM inhibited both osmotic hemolysis and osmotic volume change of the red blood cell in hypotonic and hypertonic NaCl solutions, respectively. 3) Benzyl alcohol inhibited both Bowditch Staircase and Wood-worth Staircase phenomena at rat left auricle. 4) Benzyl alcohol at concentration of 5 mM increased $Ca^{++}-ATPase$ activity of red blood cell ghosts slightly but above S mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. 5) Benzyl alcohol at concentrations of 5 mM and 10 mM increased $Ca^{++}-ATPase$ activity slightly at rat gastrocnemius muscle S.R. but above 10 mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. Above results indicate that benzyl alcohol inhibit water permeability and $Ca^{++}$ transport across cell membranes in part via effects on the fluidity and transition temperatures of the bulk lipid by preferential intercalation into cytoplasmic monolayer and in part via other effect on the conformational change of active sites of the $Ca^{++}-ATPase$ molecule extended in cytoplasmic face.

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식물성 식용유로 사육한 토끼근육의 근원섬유 단백질의 ATPase 활성에 미치는 금속의 영향 (The effect of the divalant Metal ions on the ATPase activity in Myofibrillar protein of the Muscle of Rabbit fed Vegetable Oils.)

  • 남현근
    • 한국미생물·생명공학회지
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    • 제8권2호
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    • pp.113-117
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    • 1980
  • 식물성 식용유를 기본식이에 첨가하여 일정한 조건하에서 사육한 토끼 근육에서 근원섬유 단백질을 추출하여 ATPase활성과 이에 미치는 EDTA, $Ca^{2+}$, $Mg^{2+}$ 등의 여러가지 농도변화에 따른 한성도 저해 양상을 조사한 결과는 다음과 같다. 1. 근원섬유 단백질의 ATPase 환성은 KCI의 농도가 크면활성은 감소되고, 농도가 감소되면 황성은 증가되었으며 대조군보다 식용유를 급여한 군이 더 높았다. 2, EDTA의 농도변화에 따른 ATPase 학성은 0.2mM EDTA 이상부터 찬성방해작용이 현저히 나타났다. 3. $Ca^{2+}$, $Mg^{2+}$이 ATPase 활성에 미치는 영향을 보면 0.2mM $Ca^{2+}$ 이상의 농도에서부터, 1.0mM $Mg^{2+}$ 이상의 농도에서부터 ATPase 활성 방해작용이 뚜렷이 나타났다. 4. In vitro 소화율은 pepsin으로 처리하여 대조군이 71.66%, 들깨기름 급여군이 70.62%, 콩기름 급여군이 67.93%, 미강유 급여군이 86.79% 이었고, Trypsin으로 처리하면 대조군이 73.87%, 들깨기름 급여군이 77.93% 콩기름 급여군이 76.52%, 미강유 급여군이 90.22%를 보였다. 이는 pepsin에 의한 소화보다 Trypsin에 의한 소화력이 더 좋음을 나타내며 식물성 기름을 급여한 군의소화율이 더 좋음을 알 수 있었다.

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Actomyosin $Ca^{++}$ Activated Adenosinetriphosphatase 활성도에 대한 pH 및 온도의 영향 (pH-Temperature Dependence of the Ca-ATPase Activity in Actomyosin Systems of Rabbit and Frog Skeletal muscle)

  • 김희중;황애란;박양생;강두희
    • The Korean Journal of Physiology
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    • 제11권2호
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    • pp.1-7
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    • 1977
  • The activity of the $Ca^{++}$ activated adenosinetriphosphatase (Ca-ATPase) of actomyosin systeme of rabbit and frog skeletal muscle has been studied at varying pH and temperature. The PH optima of the Ca-ATPase activity of the rabbit actomyosin was rather broad. Over the temperature range of $16-36^{\circ}C$ activity of the enzyme was not appreciably changed between pH 6.4-8.5; below and above which it rapidly reduced. The pH at the inflection point of the enzyme activity increased as temperature decreased, showing the ${\bigtriangleup}pH\;inflection/{\bigtriangleup}T$ of approximately $-0.018\;unit/^{\circ}C$. Consequently, $(OH^-)/(H^+)$ ratio at the inflection point was constant regardless of assay temperature. In the frog actomyosin systems the Ca-ATPase activity was not apparently altered between PH 6.4-7.0 when the incubation temperature was $15{\sim}30^{\circ}C$. Outside of this range of pH, however, the enzyme activity was dramatically decreased. The pH of the inflection point changed inversely with temperature. ${\bigtriangleup}pH\;inflection/{\bigtriangleup}T$ at the acidic side was approximately $-0.018\;unit/^{\circ}C$, whereas that at the alkaline side it was about $-0.037\;unit/^{\circ}C$. The Arrhenius Plot on the Ca-ATPase activity at constant $(OH^-)/(H^+)$ ratio of 1.0 was not linear, but showed break at arround $20^{\circ}C$ for both rabbit and frog actomyosin Preparations. From these results it was speculated that pH dependence of Ca-ATPase activity of rabbit actomyosin systems might reflect titrations of histidine-imidazole and -SH groups, and that of the frog actomyosin represents titrations of histidine-imidazole and lysyllysine ${\alpha}-NH_2$ groups.

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개고기 다리와 가슴 근육에서 추출한 근원섬유 단백질의 특성 (Characteristics of Myofibrillar Protein Extracted Leg and Breast Muscles of Dog Meat)

  • 박경숙;윤동화;정인철
    • 동아시아식생활학회지
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    • 제16권4호
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    • pp.453-457
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    • 2006
  • This study investigated the extractability, solubility, Mg$^{2+}$-, Ca$^{2+}$- and EDTA-ATPase activity of actomyosin prepared from leg and breast muscle of dog meat. The actomyosin extractability of breast muscle(2,100.6 mg/l00 g) was higher than that of leg muscle(500.8 mg/l00 g). The Mg$^{2+}$-ATPase activity of actomyosin had a high ionic strength of 0.02$\sim$0.05 M KCI and did not differ between leg and breast muscle. The Ca$^{2+}$-ATPase activity of actomyosin had a high ionic strength of 0.02$\sim$0.10 M KCI and leg muscle had a higher level of Ca$^{2+}$-ATPase activity than breast muscle did. The EDTA-ATPase activity was lower in low ionic strength and showed higher in high ionic strength, and increased sharply with increasing ionic strength up to 0.3 M KCI. The solubility of actomyosin did not differ between leg and breast muscle, and the solubility started and ended at KCI concentrations of 0.35 M and 0.4 M, respectively.

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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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연체류의 근원섬유단백질에 관한 연구 (Studies on the Myofibrillar Proteins of Mollusca)

  • 신완철;송재철;김영호
    • 한국식품영양학회지
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    • 제10권2호
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    • pp.151-159
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    • 1997
  • 근원섬유단백질의 이온강도에 따른 Ca-ATPase 활성, Mg-ATPase 활성 및 EDTA-ATPase 활성은 오징어와 대합에서 그 차이점이 뚜렷하였으며, activity-pH curve에서 오징어 actomyosin의 Ca-ATPase 활성은 biphasic response가 소실되었고 대합의 actomyosin은 미약한 bipasic response가 나타났다. 또한 저농도의 dioxane에 의하여 오징어의 근원섬유단백질은 급격한 활성의 감소를 보였으나 대합의 근원섬유단백질은 활성이 증가되었다. 그리고 에탄올과 메탄올은 오징어와 대합의 myosin 및 MM에 대하여 저농도에서 활성을 증가시켰다. 한편 NEM으로 근원섬유단백질을 modification시키며 10-6M 이하의 NEM 농도에서는 활성이 증가되었으나 10-5M 이상의 농도가 되면 활성의 급격한 감소가 나타났다.

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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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Optimal Conditions for the Distribution of Cryoprotectant into the Intact Fish Muscle of Oncorhynchus mykiss during Freeze/Thaw Cycling

  • Kong Chang Suk;Park Kun Young
    • Fisheries and Aquatic Sciences
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    • 제8권1호
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    • pp.10-16
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    • 2005
  • Conditions for sufficient and rapid distribution of a cryoprotectant (sorbitol solution) into intact fish muscle (Oncorhynchus mykiss) were studied as changing in the residual Ca2+ ATPase activity during freeze/thaw cycling. Chunks of the fish muscle were immersed in 4 concentrations of sorbitol solutions ($20\%$, $30\%$, $45\%$, and $60\%$) by a shaker mechanism at 5$^${circ}C. Whole immersion samples (W) showed a higher value of the residual Ca2+ ATPase activity than those in the untreated controls (C), except in the treated controls (TC), while less effect of immersion concentration could be found. Comparing the extent of penetration of sorbitol into the surface layer to inner layer of immersed fish chunks, outer portion samples achieved excellent cryoprotection with $100\%$ of the residual ATPase activity values or more. For the inner portion samples, $30\%$ and $45\%$ sorbitol solution treatments indicated a higher ATPase activity than $60\%$ treatment. At high concentrations, mass transfer rates during osmotic dehydration might berapid and it causes faster surface drying by dewatering at surface solute layer. Periodically immersed and relaxed samples, W (5-3-1), led to good cryoprotection effect: W (5-3-1) indicated high residual Ca2+ ATPase activity values and the residual ATPase activity values excess $100\%$ in immersion of $30\%$ and $45\%$ sorbitol solutions.