• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.183-185
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• 2011

Adenylate kinase-like activity and phosphotransferase-like activity from $F_1$-ATPase of Escherichia coli was revealed by $^{31}P$ NMR spectroscopy. Incubation of F1-ATPase with ADP in the presence of $Mg^{2+}$ shows the appearance of $^{31}P$ resonances from AMP and Pi, suggesting generation of AMP and ATP by adenylate kinase-like activity and the subsequent hydrolysis to Pi. Incubation of $F_1$-ATPase with ADP in the presence of methanol shows additional peak from methyl phosphate, suggesting phosphotransferase-like activity of $F_1$-ATPase. Both adenylate kinase-like activity and phosphotransferase-like activity has not been reported from $F_1$-ATPase of Escherichia coli. $^{31}P$ NMR could be a valuable tool for the investigation of phosphorous related enzyme.

• 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.

• BMB Reports
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• 제31권1호
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• pp.44-47
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• 1998

Asymmetry amongst nucleotide binding sites of Escherichia coli $F_1$-ATPase was examined using $^{19}F$ NMR signal from fluorinated analogs of adenine nucleotides bound to nucleotide binding sites. ADP-$CF_2-{PO_3}^{2-}$ showed no inhibitory effect to $F_1$-ATPase. But ADP-CHF-${PO_3}^{2-}$ (racemic mixture) showed competitive inhibition of $F_1$-ATPase with $K_i$ of $60\;{\mu}m$. ADP-CHF-${PO_3}^{2-}$ shows only negligible binding to $EF_1$ in the absence of $Mg^2+$. With the addition of $Mg^2+$ to the medium, the $^{19}F$ resonance of free ADP-CHF-${PO_3}^{2-}$ disappeared and the new broad resonances appeared. Appearance of more than two new asymmetric resonances following the binding of ADP-CHF-${PO_3}^{2-}$ to $EF_1$ may indicate that at least one of the isomers showed split resonances. This may suggest that the region between ${\alpha}$-and ${\beta}$-phosphate of ADP-CHF-${PO_3}^{2-}$ which is bound to catalytic sites is experiencing a different environment at different sites.

• 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.

• 대한의생명과학회지
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• 제13권3호
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• pp.169-173
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• 2007

[ $^{31}PNMR$ ] spectroscopy revealed the adenylate kinase-like activity and the phosphotransferase activity from $F_1-ATPase$ of Escherichia coli. Incubation of $F_1-ATPase$ with ADP in the presence of $Mg^{2+}$ shows the appearance of $^{31}P$ resonances from AMP and Pi, suggesting the generation of AMP and ATP by adenylate kinase-like activity and the subsequent hydrolysis to Pi. Incubation of $F_1-ATPase$ with ADP in the presence of methanol shows additional peak from methyl phosphate, suggesting phosphotransferase activity of $F_1-ATPase$. Both adenylate kinase-like activity and the phosphotransferase activity has not been reported from $F_1-ATPase$ from Escherichia coli. $^{31}P$ NMR proved that it could be a valuable tool for the investigation of phosphorous related enzyme.

• 한국균학회지
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• 제19권3호
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• pp.214-219
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• 1991

1. 표고버섯, L. edodes 중의 adenosine-5'-triphosphatase를 황산암모늄 30% 포화로 분별침전 및 Sephadex G-200 겔 여과로 정제하였다. 2. 이 버섯 중에는 3종류의 단백질 분획과 adenosine-5'-triphosphate 기질에 대한 두 종류의 활성분획 I, II, III 및 IV를 얻었다. 3. 활성분획 II를 정제하여 얻은 이 효소의 최적 pH 및 최적 온도는 각각 7.6 및 $58^{\circ}C$였고, 열 안정성은 $20-40^{\circ}C$에서 30분 동안 안정하였다. 이 효소의 Km값은 1.81mM이었다.

• Bulletin of the Korean Chemical Society
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• 제22권1호
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• pp.90-92
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• 2001

• 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.

• 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.