• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.454-458
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• 2002

Furo[3,2-h]quinoline derivatives were synthesized as a gastric $H^+$/$K^+$-ATPase inhibitors. The oxycyclization of 7 and 8-positions in quinoline potentiated the inhibitory activity, while no significant changes in biological activity were observed by the variation of substituents in furan ring. The several furo[3,2-h]quinoline derivatives were worthy of in vivo investigation for their anti-secretory and anti-ulcer activity.

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1217-1223
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• 2001

A series of benzimidazole derivatives containing oxycyclic pyridine was prepared and evaluated for their gastric H+ /K+ -ATPase inhibitory activity. Several of the synthesized compound exhibited potent antisecretion in pylorus-ligated rats when administered intradoudenally. Their inhibitory activities were equivalent or comparable to omeprazole.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.414-421
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• 1999

Helicobacter pylori were found to be resistant to azide but sensitive to vanadate, suggesting that defect in the P-type ATPase activity rather than F-type ATPase would be lethal to cell survival or growth. To elucidate the relationship between this enzyme inhibition and H. pylori death, we determined the effect of omeprazole (OMP) plus vanadate on enzyme activity and cell growth. The minimum inhibitory concentration (MIC; ca. 0.8$\mu$mol/disk) of vanadate for H. pylori growth was lowered over l0-fold with the aid of OMP, whereby its inhibitory potential toward the P-type ATPase activity was diametrically increased. Alternatively, we found that this enzyme activity was essential for active transport in H. pylori. From these observations, we strongly suggest that the immediate cause of the growth inhibition of H. pylori cells with OMP and/or vanadate might be defective in the cell's active transport due to the lack of P-type ATPase activity. From the spectral data with circular dichroism (CD) spectroscopy, we found that activated OMP (OAS) at concentration below MIC did not disrupt helical structures of membrane proteins. Separately, we determined the cytopathic effect of OAS by SDS-PAGE, indicating the change in the production of cytoplasmic protein but not cell membrane.

• Biomolecules & Therapeutics
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• 제24권5호
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• pp.453-468
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• 2016

There is a conserved ATPase domain in topoisomerase II (topo II) and heat shock protein 90 (Hsp90) which belong to the GHKL (gyrase, Hsp90, histidine kinase, and MutL) family. The inhibitors that target each of topo II and Hsp90 are intensively studied as anti-cancer drugs since they play very important roles in cell proliferation and survival. Therefore the development of dual targeting anti-cancer drugs for topo II and Hsp90 is suggested to be a promising area. The topo II and Hsp90 inhibitors, known to bind to their ATP binding site, were searched. All the inhibitors investigated were docked to both topo II and Hsp90. Four candidate compounds as possible dual inhibitors were selected by analyzing the molecular docking study. The pharmacophore model of dual inhibitors for topo II and Hsp90 were generated and the design of novel dual inhibitor was proposed.

• 한국미생물·생명공학회지
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• 제33권4호
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• pp.260-266
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• 2005

본 실험에서는 MRF가 다량 존재하는 RBL-2H3 세포주에 다양한 PKC isotype별 억제제를 처리하여 in vitro상에서 Na, K-ATPase $\alpha$1L3를 이용한 pull-down assay와 RBL-2H3 세포를 이용한 membrane fractionation을 실시하였다. 그 결과 HRF는 in vitro에서 $\alpha$1L3와 결합한다는 사실을 재확인 할 수 있었고 실제 세포주 내에서 Na,K-ATPase와 결합한다는 것을 알 수 있었다. 사용한 약물로부터 PKC $\alpha,\;\beta,\;\delta$뿐 아니라 protein phosphatase 2B(PP2B)도 HRF와 $\alpha$1L3의 결합에 관여한다는 사실을 알 수 있었다. 또한 이들 PKC, PP2B에 의해 인산화된 HRF 분자는 cytosolic fraction으로 이행할 수 있으며 이러한 결과는 탈인산화된 HRF가 Na,K-ATPase와 결합하여 Na, K-ATPase의 기능을 조절한다고 추정할 수 있다. 그러나 약물자체가 histamine 분비에 영향을 미칠 수 있으며 cytosolic HRF보다 exocytosis된 HRF가 histamine를 더 분비하도록 할 수 있으므로, 약물을 전처리한 세포에 외부에서 HRF를 첨가하여 histamine이 유리되는 정도가 어떻게 변화하는지를 HRF를 가하지 않은 결과와 비교해야 할 것이다.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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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.

• 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.

• BMB Reports
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• 제40권1호
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• pp.7-14
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• 2007

Helicases are ubiquitous enzymes, which utilize the energy liberated during nucleotide triphosphate hydrolysis to separate double-stranded nucleic acids into single strands. These enzymes are very attractive targets for the development of new antibacterial compounds. The PcrA DNA helicase from Staphylococcus aureus is a good candidate for drug discovery. This enzyme is unique in the genome of S. aureus and essential for this bacterium. Furthermore, it has recently been published that it is possible to identify inhibitors of DNA helicases such as PcrA. In this report, we study the properties of recombinant PcrA from S. aureus purified from Escherichia coli to develop ATPase and helicase assays to screen for inhibitors.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.1091-1094
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• 2004

• 한국환경농학회지
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• 제21권2호
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• pp.102-108
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• 2002

염류장애에 의한 작물의 생육저해 원인을 밝혀내기 위하여 상추를 대조양액과 대조양액에 30 mM 및 50 mM $KNO_3$를 첨가하여 염류농도를 높인 양액 등 3가지 조건에서 재배하였으며, 이때 이들 양액의 EC는 각각 1.0, 4.5, 6.5 dS/m 이었다. 뿌리세포의 원형질막 및 액포막에 위치한 $H^+$-ATPase 활성은 각각에 특이적 저해제인 vanadate와 $NO_3^-$를 이용하여 측정하였다. 대조양액에서 재배한 상추 뿌리의 ATPase 활성은 $356\pm1.5$ nmol/min/mg protein이었으며, 30 mM과 50 mM $KNO_3$를 첨가한 양액에서는 활성이 대조활성에 비하여 각각 1.6배, 1.9배 증가하였다. 이것은 상추가 염류장애시 뿌리조직의 ATPase 활성증가를 통하여 적응함을 보여주는 것이며, 활성증가는 주로 액포막 $H^+$-ATPase 활성증가에 의해 이루어짐을 확인하였다. 마이크로솜 ATPase 활성에 미치는 여러 가지 중금속 이온들의 효과를 측정하였으며, 중금속 이온은 100 ${\mu}M$ 농도에서 콩류에 따라 활성을 10$\sim$25% 저해하였다. 특히, $Cu^{2+}$는 주로 액포막 $H^+$-ATPase 활성을 저해함을 확인하였다. 본 연구의 결과로부터 상추는 염류집적 환경에서 뿌리의 ATPase 활성, 특히 액포막에 위치한 $H^+$-ATPase 활성을 증가시켜 적응하며, $Cu^{2+}$는 주로 액포막 $H^+$-ATPase 활성을 저해하는 성분으로 뿌리의 ATPase 활성변화 연구에 유용하게 이용될 수 있음을 확인하였다.