• 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.

• 한국균학회지
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• 제22권2호
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• pp.122-129
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• 1994

표고버섯의 mitochondria에 금속 chelating agent인 10 mM EDTA 및 10 mM o-Phe을 포함하는 10 mM Tris-HCl 완충용액(pH 7.5)으로 48시간 동안 각각 투석처리 하였을 때 mitochondria 내의 철 이온 함량이 투석처리를 하지 않은 대조구에 비하여 각각 74% 및 68% 감소되며, mitochondrial $F_1-ATPase$의 활성도는 대조구에 비하여 각각 56% 및 49%의 활성을 상실하였다. EDTA 투석에 의하여 활성을 상실한 metal-free mitochondrial $F_1-ATPase$는 $0.5\;mM\;Fe^{3+}$과 $0.05\;mM\;Mg^{2+}$에 의하여 각각 81% 및 70%의 활성이 회복되었으며, $Fe^{2+}$에 의해서는 활성이 회복되지 않았다. 또한 이 효소는 $0.5\;mM\;Fe^{3+}$와 $0.05\;mM\;Mg^{2+}$이 공존할 때 95%의 재활성화를 나타내었으며, $Fe^{2+}$와 $Mg^{2+}$의 공존 효과는 없었다. o-Phe으로 투석한 효소도 각 이온에 대하여 EDTA로 투석한 효소와 유사한 결과를 나타내었다. 그러므로, 표고버섯 내의 mitochondrial $F_1-ATPase$는 그 활성을 나타내는 데 있어서 $Fe^{3+}$ 및 $Mg^{2+}$을 필요로 함을 알았다. 기질 ATP에 대한 효소의 Km값은 1.67 mM이나, 효소를 가장 크게 활성화시키는 $0.5\;mM\;Fe^{3+}$와 $0.05\;mM\;Mg^{2+}$이 존재할 때의 Km값은 0.65 mM로서 기질 친화성이 증가되었다.

• 한국균학회지
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• 제21권3호
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• pp.157-164
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• 1993

1. 표고버섯중 광감응성 mitochondrial $F_1-ATPase$는 $Fe^{3+},\;Fe^{2-}$ 및 $Mg^{2+}$ 이온에 의하여 각각 활성화 되었으나 5.0 mM $Fe^{3+}$ 이온에 의한 상대활성도는 대조구에 비하여 107% 증가시켰다. 2 $Mg^{2+}$ 존재하에서 $Fe^{3+}$ 및 $Fe^{2-}$ 각 이온 농도효과는 모두 효소의 활성을 증가시켰으나 0.1 mM $Mg^{2+}$과 5.0 mM $Fe^{3+}$ 이온의 공존하에서 170%를 증가시켜 $Mg^{2+}$ 이온에 의한 상승작용을 보였다. 3. 0.1 mM $Mg^{2+}$와 0.1 mM $Fe^{2+}$ 존재하에서 $Fe^{3+}$ 이온농도효과는 그 농도가 5.0 mM일 때 168%의 활성도 증가를 보여 $Fe^{2-}$ 이온공존효과는 없었다. 4. 이 효소는 $Mg^{2+}$ 및 $Fe^{3+}$ 이온에 의하여 활성화되는 특성을 가지고 있으며 활성금속이온 존재하에서 측정한 최적 pH 빛 온도는 각각 7.5 및 $66^{\circ}C$였다.

• 한국균학회지
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• 제21권3호
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• pp.165-171
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• 1993

표고버섯 중의 광감응성 mitochondrial ATP synthase는 0.1 mM $Fe^{2+}$ 단독 이온에 의하여 그 활성이 대조구에 비해 102%, 증가되었으며, 반면 $Fe^{3+}$ 및 $Mg^{2+}$ 이온은 효소의 활성을 억제시켰다. 0.5 mM $Mg^{2+}$ 존재하에서 0.1 mM $Fe^{2+}$ 이온에 의한 이 효소의 활성은 32% 증가되었으며 0.5 mM $Mg^{2+}$ 존재하에서 $Fe^{3+}$ 이온효과는 단독 $Fe^{3+}$ 이온의 효과와 유사한 경향으로 효소의 활성을 저해하였다. 0.5 mM $Mg^{2+}$과 0.1 mM, 0.5 mM 및 1.0 mM $Fe^{3+}$ 이온의 공존하에서$Fe^{2+}$ 이온에 의한 효소의 활성은 모두 억제되었으며, 특히 0.5 mM $Mg^{2+}$과 0.1 mM $Fe^{3+}$ 이온의 공존하에서 5.0 mM $Fe^{2+}$ 이온에 의하여 53%의 억제현상을 나타내었다. 따라서 표고버섯 중의 광감응성 mitochondrial ATP synthase의 활성은 $Fe^{2+}$ 이온에 의하여 특이적으로 크게 증가되며, 이 효소에 대한 $Fe^{2+}$ 이온의 활성화 효과가 $Mg^{2+}$ 이온에 의하여 크게 영항을 받지 않으나, $Fe^{3+}$ 이온의 공존하에서는 억제됨을 알았다. 활성화 금속이온인 $Fe^{2+}$ 존재하에서 이 효소의 최적 pH는 7.6이며, 최적 온도는 $63^{\circ}C$이었다. 또한 이 효소는 금속 chelating agent인 EDTA에 의하여 효소의 활성이 상실됨으로써 metalloenzyme의 가능성을 제시하였다.

• 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.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.104-105
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• 1996

• 대한지역사회영양학회:학술대회논문집
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• 대한지역사회영양학회 1997년도 추계학술대회:건강증진을 위한 영양서비스 접근방향
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• pp.52-52
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• 1997

no Abstract, See Full Text

• Journal of Microbiology and Biotechnology
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• 제10권4호
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• pp.441-448
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• 2000

The production and cation flux-mediated activation of the P-type ATPase in Helicobacter pylori was investigated. Using the polymerase chain reaction (PCR), the proton pump genotype of H. pylori was found to be positive for both F-type and P-type ATPases. Yet, their production in terms of enzyme specific activity varied substantially depending on H. pylori strains, ranging over 3-fold. Its main constituent appeared to be the P-type ATPase pool, in contrast to other common bacterial compositions. Interestingly, the F-type ATPase was observed only when intact H. pyloricells were exposed to pH 4.5 or above (37$^{\circ}C$ for 1 h). In contrast, significant amounts of the P-type ATPase still remained after 1 h of cell treatment even at pH below 4.5. By enriching the acidic medium with RPMI(pH 3.0), the P-type ATPase was stabilized, accompained by inactivation of the F-type ATPase. Using H. pylori membrane vesicles, it was found that ammionia-mediated cation flux increased the rate of ATP hydrolysis by the P-type ATPase. Accordingly, these data strongly suggest that the P-type ATPase is involved or functions as an effective regulator for the cation flux across the H. pylori membrane, thereby reducing the risk of excess proton influx.

• 한국균학회지
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• 제19권3호
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• pp.220-225
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• 1991

1. 표고버섯 중 정제된 ATPase는 $Fe^{3+},\;Fe^{2+},\;Cd^{2+},\;Mg^{2+},\;K^{+}$ 및 $Co^{2+}$ 이온에 의하여 활성화 되었으나 $Zn^{2+},\;Ca^{2+},\;Cu^{2+}$ 및 $Ni^{2+}$ 이온에 의하여는 그 활성도가 억제되었다. 2. 5 mM $Fe^{3+}$, 10 mM $Fe^{2+}$, 1 mM $Cd^{2+}$, 5 mM $Mg^{2+}$, 5 mM $K^{+}$ 및 5 mM $Co^{2+}$이온은 이효소의 활성을 각각 130, 65, 65, 68, 105 및 23% 증가시켰다. 3.10 mM $Zn^{2+}$, 10 mM $Ca^{2+}$, 0.5 mM $Cu^{2+}$ 그리고 10 mM $Ni^{2+}$ 이온은 이효소의 활성을 각각 18, 19, 27% 그리고 30%의 억제효과를 보였다. 4. 10 mM ${Co_3}^{2-}$, 20 mM $CN^{-}$, 20 mM ${CH_3COO}^{-}$ 그리고 20 mM ${NO_3}^{-}$의 음이온은 이효소의 활성을각각 98, 95, 70% 그리고 50%를 억제시켰으나,${SO_4}^{2-}$ 이온은 농도증가에 따라 활성화 되었고, 20 mM 용액에서 21%로 활성도 증가의 최대치를 보였다.

• BMB Reports
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• 제34권6호
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• pp.573-577
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• 2001

The mammalian heart is known to undergo significant mechanical changes during fetal and neonatal development. The objective of this study was to define the ontogeny of the ryanodine receptor/$Ca^{2+}$ release channel and SERCA that play the major roles in excitation-contraction coupling. Whole ventricular homogenates of fetal (F) (19 and 22 days in gestation), postnatal (N) (1 and 7 days postnatal), and adult (A) (5 weeks postnatal) Sprague-Dawley rat hearts were used to study [$^3H$]ryanodine binding and oxalate-supported $^{45}Ca^{2+}$ uptake. For the ryanodine receptor, the major findings were: (1) The ryanodine receptor density, as determined by maximal [$^3H$]ryanodine binding ($B_{max}$), increased 3 fold between the F22 and A periods ($0.26{\pm}0.1$ vs. $0.73{\pm}0.07$ pmoles/mg protein, p<0.01), whereas there was no significant change during the F22 and N1 development phases ($0.26{\pm}0.1$ vs. $0.34{\pm}0.01$). (2) Affinity of the ryanodine receptor to ryanodine did not significantly change, as suggested by the lack of change in the $K_d$ during the development and maturation. For SERCA, changes started early with an increased rate of $Ca^{2+}$ uptake in the fetal periods (F19: $8.1{\pm}1.1$ vs. F22: $19.3{\pm}2.2$ nmoles/g protein/min; p<0.05) and peaked by 7 days (N7) of the postnatal age ($34.9{\pm}2.1$). Thus, we conclude that the quantitative changes occur in the ryanodine receptor during myocardial development. Also, the maturation of the $Ca^{2+}$ uptake appears to start earlier than that of the $Ca^{2+}$ release.