• The Korean Journal of Zoology
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• v.17 no.2
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• pp.93-102
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• 1974

Fragmente dsarcoplasmic reticulum of rabbit skeletal muscle was prepared and biochemical properties of its ATPase activity were studied. The ATPase of the fragments could be distinguished as $Mg^++ - ATPase and (Mg^++ - Ca^++)$-ATPase. The activity of $(Mg^++ - Ca^++)$-ATPase was predominant over that of $Mg^++$-ATPase in the temperature range of $0 \\sim 40^\\circ C$ and in the pH 6.4$\\sim$7.6. At higher temperatures the predominance of $(Mg^++ - Ca^++)$-ATpase was far greater. The apparent energies of activation were 14 kcal/mole for $Mg^++$-ATPase, 21kcal/mole for $(Mg^++ - Ca^++)$-ATPase, and 18kcal/mole for total ATPase. Changes in pH and Mg concentration did not alter the energies of activation of these ATPases. The Km values of these ATPases were found to be 0.36 mM for $Mg^++$-ATPase, 2.20 mM for $(Mg^++ - Ca^++)$-ATpase, and 0.86 mM for total ATPase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.9 no.1
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• pp.45-50
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• 1980

Myofibrilar Protein from Korean Duck Muscle was extracted and ATPase activities were studied. The results were as follows: 1. Mg-activated ATPase activity of Myofibril from Korean Duck, muscle exhibited a biphasic response, ATPase activity was high at a low ionic strength and low activity was showed at high ionic strength. 2. Effect of EDTA on the Myofibrillar protein ATPase activity was studied, it was investigated that the EDTA inhibition was showed at the concentration of $6.9{\mu}g$ and it above. 3. It showed that the effect of Ca++ on ATPase activity was decreased at the lower than $3{\mu}g$. Inhibition showed at the concentration of $6.9{\mu}g$ and it above. 4. It showed that the effect of Mg++ on ATPase activity was decreased at the lower than $3.6{\mu}g$. Inhibition showed at the concentration of $3.9{\mu}g$ and it above.

• Journal of Sericultural and Entomological Science
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• v.42 no.1
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• pp.14-23
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• 2000

The mitochondrial genome of domesticated silkworm (Bombyx mori) was mapped with five restriction endonucleases (BamHI, EcoRI, HindIII, PstI and XbaI), the entire genome was cloned with HindIII and EcoRI. From the end sequencing results of 5$^1$and 3$^1$region for full genome set of eleven mitochondrial clones, the seven mitochondrial genes (NADH dehydrogenase 6, ATPase 6, ATPase 8, tRN $A^{Lys}$, tRN $A^{Asp}$, tRN $A^{Thr}$ and tRN $A^{Phe}$ of mori were identified on the basis of their nucleotide sequence homology. The nucleotide composition of NADH dehydrogenase 6 was heavily biased towards adenine and thymine, which accounted for 87.76%. On basis of the sequence similarity with published tRNA genes from six insect species, the tRN $A^{Lys}$, tRN $A^{Asp}$ and tRN $A^{Thr}$ were showed stable canonical clover-leaf tRNA structures with acceptible anticodons. However, both the DHU and T$\psi$C arms of tRN $A^{Phe}$ could not form any stable stem-loop structure. The two overlapping gene pairs (tRN $A^{Lys}$ -tRN $A^{ASP}$ and ATPase8-ATPase6) were found from our sequencing results. The genes are encoded on the same strad. ATPase8 and ATPase6 overlaps (ATGATAA) which are a single example of overlapping events between abutted protein-coding genes are common, and there is evidence that the two proteins are transcribed from a single bicistronic message by initiation at 5$^1$terminal start site for ATPase8 and at an internal start site for ATPase6. Ultimately, this result will provide assistance in designing oligo-nucleotides for PCR amplification, and sequencing the specific mitochondrial genes for phylogenetics of geographic races, genetically improved silkworm strains and wild silkworm (mandarina) which is estimated as ancestal of domesticated silkworm.sticated silkworm.

• The Korean Journal of Physiology
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• v.17 no.2
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• pp.161-168
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• 1983

Studies on the effects of vanadate for Na-K-ATPase activity were carried out with rabbit renal cortex. 1) Na-K-ATPase activity was inhibited with the concentrations of vanadate in incubation medium. The vanadate concentration at which activity was inhibited by 50%$(ID_{50})$ was $10^{-6}M$ and Hill coefficient was 1.00. 2) The fractional inhibition by constant concentration of vanadate decreased with increasing enzyme concentration. 3) Increasing $K^+$ and $Na^+$ concentrations in incubation medium diminished the ability to inhibit Na-K-ATPase by vanadate whereas increasing $K^+$ and $Mg^{2+}$ concentrations potentiated the inhibition of Na-K-ATPase by vanadate. 4) Vanadate didn't inhibit Na-K-ATPase at pH 6.6. Increasing pH potentiated the inhibition of Na-K-ATPase activity. 5) Vanadate inhibited Na-K-ATPase activity reversibly in all range of concentrations in dilution experiment. These results show that vanadate inhibits Na-K-ATPase activity with interacting at $KE_2$ state reversibly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.349-354
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• 1997

Myotibrillar ATPase activity, thermostability and composition of muscle protein were investigated to elucidate biochemical properties regard with rearing period and sex of olive flounder. Myofibrillar ATPase activity of male olive flounder reared for 6, 12 and 20 months was stronger than that of female one. $Mg^{2+}\;(+Ca^{2+})-ATPase$ activity of both female and male fish decreased with the elapse of rearing period, and the activity of male was higher than that of female far beyond the rearing periods. The high correlationship between the weight gain and myofibrillar ATPase activity was observed. The thor mostability of male myofibrillar protein was higher than that of female. Subunit composition of the myofibrillar and sarcoplasmic protein did not show difference between the both sex of the fish.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.102-108
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• 2002

In order to investigate the mechanism of growth inhibition by salt stress, lettuces were grown hydroponically in three different nutrient solutions, normal and 30 mM or 50 mM $KNO_3$-added nutrient solutions, and the electrical conductivities of these solutions were 1.0, 4.5, and 6.5 dS/m, respectively. The activities of plasma and vacuolar $H^+$-ATPases in the root tissue of lettuce were measured by specific inhibitors, 100 ${\mu}M$ vanadate and 50 mM $NO_3^-$, respectively. Microsomal ATPase activity of lettuce grown in the normal nutrient solution was $356\pm1.5$ nmol/min/mg protein. When lettuces were grown in 30 mM and 50 mM $KNO_3$-added nutrient solutions, total activities of microsomal ATPases were increased by 1.6 and 1.9 times, respectively, and the increases were mainly mediated by vacuolar $H^+$-ATPase. These results show that lettuces adapt themselves to salt-stressed condition by increasing the activities of $H^+$-ATPases. Effects of various heavy metal ions were investigated on the microsomal ATPases and various metal ions at 100 $\mu M$ inhibited the activities by 10$\sim$25%. $Cu^{2+}$ showed the highest inhibitory effect on the vacuolar $H^+$-ATPase. These results suggest that lettuce increases the activities of root ATPases, specially that of vacuolar $H^+$-ATPase, in salt-stressed growth conditions and $Cu^{2+}$ could be a useful tool to control the activity of vacuolar $H^+$-ATPase.

• The Korean Journal of Physiology
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• v.18 no.2
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• pp.163-169
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• 1984

The effect of vanadate on the optimum pH of Na-K-ATPase was investigated. The results were as follows: 1) The optimum PH of Na-K-ATPase was shifted from PH 7.4 to 6.8 at 10 mM K by $5{\times}10^{-6}M$ vanadate. 2) The ratio of Na-K-ATPase activity at pH 6.8 and 7.4 increased with increasing vanadate concentration. 3) Inspite of the presence of $5{\times}10^{-6}M$ vanadate Na-K-ATPase activity at pH 7.4 was higher than that at pH 6.8 below 50 mM $Na^+$, and the ratio of Na-K-ATPase activity at pH 7,4 and 6.8 was higher than that of the control. 4) Na-K-ATPase activity at pH 7.4 was higher than that at pH 6.8 below 7mM $K^+$. 5) Optimum pH of Na-K-ATPase activity was shifted from pH 7.4 to 6.8 by $10^{-5}M$ vanadate at 5 mM $K^+$. 6) $K^+$-pNPPase activity increased with lowering of pH, and the degree of inhibition of $K^+$-pNPPase activity by $10^{-7}$M vanadate was decreased with lowering of pH. These results suggest that vanadate shifts the optimum pH of Na-K-ATPase activity to more acidic PH than PH 7.4. This effect may not be caused by the decrease in the inhibitory potency of vanadate itself to Na-K-ATPase by the change of medium pH, but mainly by the alteration of Na-and K-binding site, which appears in the presence of vanadate only.

• The Korean Journal of Pharmacology
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• v.6 no.1
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• pp.1-7
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• 1970

The effects of ouabain and diphenylhydantoin on ATPase activity in rat erythrocyte membranes were studied and also influence of K on ATPase activity was studied. The ATPase activity of rat erythrocyte membrane has been shown to consist of two components. The first component requires the Mg but occurs in the absence of Na or K (Mg-ATPase) and is not inhibited by ouabain and stimulated by diphenylhydantoin. The second component requires the presence of Mg and also Na or K (Na-K-Mg-ATPase). It is inhibited by ouabain and is stimulated by diphenylhydantoin in low Na concentration and inhibited in high Na concentration. K inhibit Na-K-Mg-ATPase which is inhibited by ouabain. Ouabain and diphenylhydantoin show reversed effect to Na-K-Mg-ATPase activity. It suggest that the therapeutic effect of diphenylhydantoin on digitalis induced cardiac arrhythmia may be resulted from their effect on ion transport mechanism of cell membrance. And the relevance of these findings to the action of ouabain and diphenylhydantoin on membrane transport mechanism is discussed.

• The Korean Journal of Physiology
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• v.6 no.1
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• pp.27-31
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• 1972

The activity of Mg and Na-K activated ATPase of homogenate from rat brain cortex was measured in vitro under the variety of conditions. The effects of various hypnotic and tranquilizer such as phenobarbital, amobarbital, diazepam, promazine and chlorpromazine on the activities of both ATPase was investigated and the results was summarized as follows. 1. Na-K ATPase was slightly inhibited by phenobarbital and amobarbital while Mg ATPase was moderately activated by these drugs. 2. Both Mg and Na-K ATPase activities were markedly inhibited by diazepam. 3. Promazine and chlorpromazine markedly inhibited both Mg and Na-K ATPase activities. These findings indicate that remarkable correlation between hypnotic or tranquilizing potency and ATPase inhibition could be observed.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.151-159
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• 1997

In order to compare and examine the general characteristics of myofibrillar proteins which is an important protein source as a food resource and relates directly with muscle contraction, we have extracted the myofibrillar proteins from squid and clam. The ionic strength of myofibrillar proteins connected with Ca-ATPase activity, Mg-ATPase activity and EDTA-ATPase activity showed distinct differences between squid and clam. In the activity-pH curve, actomyosin of the clam had a weak biphasic response. In the low concentration of dioxane, myofibrillar proteins of the squid showed a sudden decrease in activity but myofibrillar proteins of the clam showed in increase in activity. Ethanol and metanol in low concentration caused myosin and HMM from the squid and clam to increase their activities. If we cause modification by NEM, under 10-6M concentration, the activity was increased but above 10-5M concentration, there was a sudden decrease in activity.