• 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.

• 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.

• 한국동물학회지
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• 제28권1호
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• pp.31-43
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• 1985

$(Ca^{2+}+Mg^{2+})$-ATPase를 쥐의 근소포체로부터 sucrose density gradient centrifugation의 방법을 사용하여 분리 정제하였다. 정제된 효소를 폴리아크릴 아마이드 젤에서 전기영동한 결과, 토끼와 닭의 경우에서와 같이 분자량 115,000인 단일 단백질 띠로 나타났다. 정제된 이 효소의 활설도는 50 $\\muM$의 $Mg^{2+}, Ca^{2+}, Co^{2+}, Fe^{2+}, Min^{2+}$에 의해서는 증가되었고, 같은 농도의 $Zn^{2+}, Cu^{2+}, Hg^{2+}$에 의해서는 감소되었다. Quinine와 quinacrine 같은 antimalarial drug는 이 효소의 활성도에 큰 영향을 주지 않았으나, p-hydroxymercuric benzoate와 phenylmethylsulfonylfluoride는 이 효소의 활성을 억제하였다. 이 효소는 pH 6과 7 사이에서 가장 높은 활성을 나타내었고, ATP를 기질로 사용하였을 때 Km 값은 98 $\\muM$이었다. $(Ca^{2+}+Mg^{2+})$-ATPase는 microsomal fraction에서 선택적으로 분해되었다. $^{3}H-casein$ 이나 ^{125}I-insulin같은 방사성 동위원소로 표지된 기질을 사용하여 단백질 분해에 대한 활성도를 조사해 본 결과, microsomal preparation에 metalloendoprotease가 존재하였다. 그러나 아직까지는 그 효소가 $(Ca^{2+}+Mg^{2+})$-ATPase를 분해하는지는 확실하지 않다.

• 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, $NO^-_3$는 $Ca^{2+}$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.

• 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.

• 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.

• 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.

• 한국식품영양과학회지
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• 제23권5호
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• pp.827-831
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• 1994

Investigation on the extractability, Mg2+-, Ca2+ , EDTA-ATPase activity and solubility of actomyosin prepared from leg and breast muscle of silky fowol were as follows. The extractability of actomyosin in leg and breast muscle was 779mg/100g and 1, 318mg/100g respectively, breast muscle was higher than leg muscle . Mg2+-ATPase activity of actomyosin was high inionic strength 0.02-0.10 and Mg2+ATPase activity of low ionic strength was higher than high ionic strength not related to the part. Ca2+ ATPase activity was high in ionic strength 0.05-0.13, the activity of leg muscle was higher that breast muscle. And EDTA-ATPase activity showed low in low ionic strength and showed high in high ionic strength, and increased greatly depend ionic strength up to 0.4. The solubility of actomyosin was not different in leg and breast muscle , the solution started in KCI concentration of 0.3M and ended in DCI concentration of 0.4M.

• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.291-298
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• 2014

We investigate the effects of cryoprotectant mixtures on the quality of sand lance surimi (SLS) during storage at $-30^{\circ}C$. We monitored freeze-induced denaturation of myofibrillar protein in SLS and examined the texture profile of SLS gel. Freeze-induced denaturation was assessed by evaluating SLS $Ca^{+2}$-ATPase activity. SLS gels prepared with sorbitol or sucrose and a mixture of both as cryoprotectant. Higher concentrations of cryoprotectants resulted in significantly higher residual SLS $Ca^{+2}$-ATPase activity at the same storage time (P < 0.05). Residual $Ca^{2+}$-ATPase activity of SLS prepared with sorbitol was higher than that of sucrose when cryoprotectant concentration and storage period were same. A blend of sorbitol and sucrose resulted in a stronger cryoprptective effect of SLS myofibrillar protein than did sorbitol or sucrose alone. The presence of a phosphate compound in SOP (3% sorbitol + 0.2% phosphate compound) resulted in higher SLS $Ca^{2+}$-ATPase activity than that of did 5% sorbitol. The hardness, brittleness, and elasticity values and a folding test of the SLS gels were significantly affected by cryoprotectant concentrations and the storage time. Preference scores and acceptance for texture in a sensory evaluation of the SLS gels increased with increasing sorbitol or sucrose concentration.

• 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.