• YAKHAK HOEJI
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• v.32 no.1
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• pp.62-69
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• 1988

We have studied the effect of fasting on $Na^+$, $K^{+}-ATPase$ activities in the rat intestinal mucosa. Rats were fasted for $18{\sim}48hr$. Intestinal microsomal fraction was prepared by the method of Robinson and ATPase activities were determined by the modified method of Fiske and Subbarow. $Na^+$, $K^{+}-ATPase$ activity was not changed after fasting for 18 and 24 hr but significantly decreased after fasting for 48 hr. Fasting over 18 to 48 hr period had no effect on the $Mg^{++}-ATPase$. Thus, it may be concluded that 48 hr fasting has inhibitory effect on rat intestinal absorptive capabilities. In order to study the effect of Ginseng on the $Na^+$, $K^{+}-ATPase$ activities of the small intestine in chronic $K^{+}-depleted$ rats, rats were fed $K^{+}-depleted$ diets for 3 weeks and Ginseng ethanol extracts were administered orally for 3 weeks concomitantly. ATPase activity was measured by the same method as fasting group. $Na^+$, $K^{+}-ATPase$ activity in the $K^{+}-depleted$ diet group was increased and Ginseng ethanol extracts inhibited the increase of enzyme activity induced by $K^{+}-depleted$ diet. Thus, it may be suggested that increase in the intestinal $Na^+$, $K^{+}-ATPase$ activity of chronic $K^{+}-depleted$ group may be due to the compensatory mechanism and administration of Ginseng with $K^{+}-depleted$ diet may be associated with inhibition of increase in the enzyme activity of the $K^{+}-depleted$ group due to the prevention of the $K^+$ loss in the $K^{+}-depletion$.

• Korean Journal of Food Science and Technology
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• v.18 no.3
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• pp.181-186
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• 1986

Myosin were prepared from red muscle and white muscle, and their ATPase activities were compared. Ca-ATPase activity of bovine myosin from red muscle was higher than that of myosin from white muscle, while Ca-ATPase activity of chicken myosin from red muscle differed hardly from that of myosin from whitemuscle. Atso EDTA-ATPase activity of bovine red muscle myosin was higher than that of white muscle myosin ,although EDTA-ATPase activity of chicken myosin from red muscle differed hardly from that of white muscle myosin. When myosins were treated with trypsin, bovine myosin from white muscle was hydrolysed moreeasily than red muscle myosin was. Chicken myosin from red muscle , however, was hydrolysed by trypsin more easily than white muscle myosin was.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.113-117
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• 1980

The effects of divalant metal ions on the ATPase activity were studied by using my of ibrillar protein of rabbit (Chin-Chilla species) fed with vegetable oils. The results obtained were as follows : 1. The ATPase activity in myofibrillar protein of the is not significant to Rabbit exhibited a common biohapsic respnse, such as the ATPase activity is high at a lower ionic strength and low at a higher ionic strength. 2. The effect of EDTA on the ATPase activity of Myofibrillar protein extracted from Rabbit fed vegetable oils was tested by using various concentrations. The ATPase activity was inhibited from 0.2mM and over concentration of EDTA. 3. The ATPase activity in Myofibrillar protein was decreased remarkably in 0.2mM and over concentration for $Mg^{2+}$, and in 1.0mM and over concentration for $Ca^{2+}$. 4. in vitro, the digestibilities in A, B, C and D groups of Rabbit muscle treated with Papsin and Trypsin for 30 minutes at 36$^{\circ}C$ water bath were 71.66％, 73.87％ ； 70.62％, 77.93％ ； 67.93％, 76.52％ ； and 86.79％, 90.22%, respectively.y.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.1-6
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• 1994

We have studied the relation between Ca$^{2+}$-ATPase and trigger peptidase(TPase) which are membeane protein well known as their significant role for signal transduction of mating pheromone in heterobasidiomycetous yeast. Rhodosporidium toruloides. We found out that there were Ca $^{2+}$-ATPase and TPase together in isolated calmodulim binding protein(CBP), usion calmodulin affinity column chromatography after solubilization of mation type a cell membrane protein, and that the dependence of enzyme activity of both the enzymes on Ca$^{2+}$, phospholipid and nonionic detergent are similar. However, Ca$^{2+}$-ATPase hed quite absolute dependence on calmodulin and, on the other hand, TPase didn't have any dependence. Judging from the fact that there are both enzymes in CBP which the dependence of calmodulin are quite different, we found out that both enzymes were made to their compound and existed in mating type a cell membrane.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.158-162
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• 2011

Amino acid sequence alignment shows that $\underline{P}$roteus $\underline{m}$irabilis $\underline{t}$ranscription $\underline{r}$egulator (PMTR) has cystein sequence homology at metal binding domain to CueR (copper resistance) protein, which conserves two cysteins (Cys 112 and Cys 120 in PMTR). Gel shift assay revealed that PMTR protein bound to promoter region of Escherichia coli copA (copper-translocating P-type ATPase) and Proteus mirabilis atpase (putative copper-translocating P-type ATPase) genes except that of E. coli zntA (zinc-translocating P-type ATPase) gene. DNase I protection experiment indicated that PMTR protein protected the region over -35 box and close to -10 box. DNase I hypersensitive bases were shown at C and A bases of labeled template strand and at G and C bases of labeled non-template strand of DNA. These hypersensitive bases were appeared in other metalloregulatory proteins of MerR family, which suggests protein-induced DNA bending.

• The Korean Journal of Pharmacology
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• v.12 no.1
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• pp.7-14
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• 1976

Aconiti tuber butanol fraction shows positive inotropic effect on the isolated atrium of rabbit heart. To investigate the mechanism, the effect on microsomal ATPase activity of rabbit heart is observed. The microsomal fraction which contains the $Na^+$- and $K^+$-activated ATPase in the presence of $Mg^{++}$ is isolated from the left ventricle of rabbit heart. The microsomal ATPase activity is maximally stimulated at $Na^+$ and $K^+$ concentration of 100 mM and 10 mM respectively. Microsomal $Na^+-K^+$-activated ATPase is inhibited by ouabain and Aconiti tuber butanol fraction. Ouabain and Aconiti tuber butanol fraction depress $Na^+$-stimulation on microsomal ATPase activity, and the inhibitory effects are not completely reversed at $Na^+$ concentration of 300 mM. Also, $K^+$-stimulation on microsomal ATPase activity is inhibited by ouabin and Aconiti tuber butanol fraction and the inhibitions are not compeletely reversed at $K^+$ concentration of 30 mM. It is, therefore, suggested that the inhibitory effect of Aconiti tuber butanol fraction on the microsomal ATPase activity may contribute to leading to the positive inotropic effect.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.163-177
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• 1988

The $Ca^{2+}-ATPase$ of sarcoplasmic reticulum (SR) was solubilized and reconstituted into a mixture of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of varying ratios in order to assess the effect of physical states of phospholipids on the incorporation and functions $Ca^{2+}-ATPase$. On the basis of the spectral data of Ca-arsenazo III, the $Ca^{2+}$ uptake of SR was increased linearly as the PC content increased in the reconstituted vesicles. The ATP hydrolysis activity also increased as PC content increased up to 25% and then decreased slightly as the PC content further increased. On the other hand the incorporation of $Ca^{2+}-ATPase$ into the reconstituted vesicls occured maximally at 25% PC and 75% PE mixture which is known to have a non-bilayer structure in reconstitution system. From the above results it is clear that preexisting defects in the lipid bilayer promote protein incorporation into the bilayer during reconstitution and lamellar structure of the bilayer facilitates the $Ca^{2+}-ATPase$ function.

• Korean Journal of Environmental Biology
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• v.34 no.2
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• pp.97-106
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• 2016

$Na^+/K^+$-ATPase is a membrane protein and plays a key role in osmotic regulation in living organisms. In the present study, a cDNA sequence encoding the $Na^+/K^+$-ATPase alpha subunit from the monogonont rotifer, Brachionus koreanus was cloned by rapid amplification of cDNA ends technique. To investigate the role of this enzyme in osmotic stress, enzymatic activities of $Na^+/K^+$-ATPase were measured after exposure to different salinities for 48 h. The full-length Bk $Na^+/K^+$-ATPase cDNA was 3069 bp-long, encoding a 1022-amino acid polypeptide. Bk $Na^+/K^+$-ATPase possesses eight membrane spanning regions and five conserved domains. Phylogenetic analysis showed that Bk $Na^+/K^+$-ATPase had high identity with those of other species, and was closely clustered with other Brachionus sp. These findings indicate that this protein was conserved both structurally and functionally. B. koreanus $Na^+/K^+$-ATPase activity was stimulated in both hyposaline (6 psu) and hypersaline (32 psu) conditions, suggesting that this protein may play a role in osmoregulation. This study would provide better understanding of the physiology of B. koreanus and this enzyme may be useful as a molecular marker for evaluation of osmotic stress in aquatic environment.

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.184-188
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• 2005

IgE-dependent histamine-releasing factor (HRF) is found extracellularly to regulate the degranulation process of histamine in mast cells and basophils and known to play a predominant role in the pathogenesis of chronic allergic disease. HRF has been also identified in the intracellular region of the cell. Previously, we reported that HRF interacts with the 3rd cytoplasmic domain of the alpha subunit of Na,K ATPase and inhibits Na,K-ATPase activity. The predicated phosphorylation site in HRF by PKC was mapped to one serine residues (S98) by the computer analysis. In this study, we identified that S98 residue of HRF was phosphorylated using anti-HRFpS98 antibody which specifically recognizes the phosphorylated serine residue of HRF and HRFS98A mutant construct. We also performed $^{86}Rb^{+}-uptake$ assay to understand the role of HRF wild-type and HRFS98A mutants on the regulation of Na,K-ATPase activity. Dephosphorylation of HRF at serine 98 residue recovers slightly the inhibitory function of HRF, suggesting that phosphorylated HRF at serine 98 may not suppress the Na,K-hfpase activity.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1717-1722
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• 2008

The 70 kDa heat-shock protein (Hsp70) involved in various cellular functions, such as protein folding, translocation and degradation, regulates apoptosis in cancer cells. Recently, it has been reported that the green tea flavonoid (−)-epigallocatechin 3-gallate (EGCG) induces apoptosis in numerous cancer cell lines and could inhibit the anti-apoptotic effect of human Hsp70 ATPase domain (hATPase). In the present study, docking model between EGCG and hATPase was determined using automated docking study. Epi-gallo moiety in EGCG participated in hydrogen bonds with side chain of K71 and T204, and has metal chelating interaction with hATPase. Hydroxyl group of catechin moiety also participated in metal chelating hydrogen bond. Gallate moiety had two hydrogen bondings with side chains of E268 and K271, and hydrophobic interaction with Y15. Based on this docking model, we determined two pharmacophore maps consisted of six or seven features, including three or four hydrogen bonding acceptors, two hydrogen bonding donors, and one lipophilic. We searched a flavonoid database including 23 naturally occurring flavonoids and 10 polyphenolic flavonoids with two maps, and myricetin and GC were hit by map I. Three hydroxyl groups of B-ring in myricetin and gallo moiety of GC formed important hydrogen bonds with hATPase. 7-OH of A-ring in myricetin and OH group of catechin moiety in GC are hydrogen bond donors similar to gallate moiety in EGCG. From these results, it can be proposed that myricetin and GC can be potent inhibitors of hATPase. This study will be helpful to understand the mechanism of inhibition of hATPase by EGCG and give insights to develop potent inhibitors of hATPase.