• 제목/요약/키워드: $F_1$-ATPase of Escherichia coli

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31P NMR Spectroscopy Revealed Adenylate kinase-like Activity and Phosphotransferase-like Activity from F1-ATPase of Escherichia coli

  • Kim, Hyun-Won
    • 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.

19F NMR Investigation of F1-ATPase of Escherichia coli Using Fluorinated Ligands

  • Jung, Seun-Ho;Kim, Hyun-Won
    • 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.

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Phosphoryl Transferring Activity was Revealed from $F_1-ATPase$ of Escherichia coli by $^{31}P$ NMR Investigation

  • Sohn, Joon-Hyung;NamKung, Jun;Yoon, Joon-Ho;Woo, Mi-Kyoung;Yeh, Byung-Il;Choi, Jong-Whan;Kim, Hyun-Won
    • 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.

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Observation of Asymmetry amongst Nucleotide Binding Sites of F1-ATPase of Escherichia coli by 31P NMR Spectroscopy

  • Jun, Nam-Kung;Sohn, Joon-Hyung;Yeh, Byung-Il;Choi, Jong-Whan;Kim, Hyun-Won
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.531-535
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    • 2011
  • It was regarded that the $^{31}P$ resonances of inherent nucleotides in $F_1$-ATPase (EF1), as large as 380KDa, could not be observed by $^{31}P$ NMR spectroscopy. However, our $^{31}P$ NMR spectroscopy could differentiate between different nucleotide binding sites on EF1 from Escherichia coli. When EF1 was prepared in the absence of $Mg^{2+}$, EF1 contained only ADP. Multiple $^{31}P$ resonances from $\beta$-phosphates of ADP bound to the EF1 were observed from the enzyme prepared without $Mg^{2+}$, suggesting asymmetry or flexibility amongst nucleotide binding sites. $^{31}P$ resonances from enzyme bound ATP could be observed only from EF1, when the enzyme was prepared in the presence of $Mg^{2+}$. This $Mg^{2+}$ dependent ATP binding was very tight that, once bound, nucleotide could not be removed even after removal of $Mg^{2+}$. $^{31}P$ NMR proved to be a valuable tool for investigating phosphorous related enzymes.

람세균 Synechocystis sp. PCC 6803 PTX의 주광성 운동에 미치는 몇가지 대사 억제제의 효과 (Effects of Some Metabolic Inhibitors on Phototactic Movement in Cyanobacterium Synechosystis sp. PCC 6803 PTX)

  • 박영총
    • Journal of Plant Biology
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    • 제38권1호
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    • pp.87-93
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    • 1995
  • 최근에 Synechocystis sp. PCC 6803 중에 한 균주가 고체 한천 배지상에서 일정한 조명(300-1000 lux) 방향을 따라 활주 운동하는 것을 관찰하여 이 종을 S. 6803 PTX라고 명명하고 이의 주광성 운동에 대한 생리학적 특징을 이해하기 위하여 몇 가지 대사 억제제와 신호 전달 차단제의 주광성 운동에 미치는 효과를 조사하였다. DCMU는 광계 II로부터 광계 I의 일차 전자 수용체인 플라스토퀴논으로의 비순환성 광합성 전자전달을 억제하는 억제자로서 $100\;\mu\textrm{M}$의 농도에서는 주광성 운동을 억제하지 못하였다. 그러나 호흡에 의한 전자전달 억제제인 sodium azide를 처리하였을 경우에는 S. 6803 PTX에서 심하게 장해를 받았다. 이러한 관찰 결과는 주광성 운동의 주동력원이 광인산화 과정보다는 호흡에 의한 산화적인 인산화과정에 주로 연관되어 있음을 보여주었다. 또한, 세포를 CCCP나 DNP와 같은 막상의 uncoupler를 처리하였을 때, 세포내 ATP 농도를 저하시키거나 세포질막에 수소 이온의 전기화학구배($\Delta\mu_{H}+$)를 제거시키나, 이러한 화합물들은 주광성 운동에 뚜렷한 영향은 주지 못하였다. 이러한 결과와는 달리, H+-F0F1 ATPase에 민감하게 억제 작용을 나타내는 DCCD나 NBD의 처리는 세포내 ATP만 고갈시키고 막상에서 $\Delta\mu_{H}+$는 그대로 유지시키는 작용을 하는데, 이러한 DCCD나 NBD는 주광성 운동에 대해서는 심하게 억제 현상을 나타내었다. 또한, 특이성 calcium ionophore 중의 하나인 A23187의 처리는 양성 주광성에 심하게 장해를 주었다. 아마도 Ca2+ 유동은 주광운동 방향성의 신호전달 과정에 중요하게 관련되어 있는 것으로 나타났다. 마지막으로 S-adenosyl methionine과 같은 메틸 공여체의 고갈이 S. 6803 PTX 균주의 주광성 반응에 영향을 주는지를 알아보기 위하여 에티오닌을 BG11을 한천 배지에 첨가하였다. 이 생물종의 광운동은 에티오닌의 농도가 증가됨에 따라 일정하게 억제되다가 0.5mM에서 주광성 운동을 완전히 억제시켰다. 이것은 광수용 기작이 Escherichia coil나 Salmonella typhimurium에서 발견된 메틸기 수용 주화성 단백질과 같은 메틸화/탈메틸화 과정에 의하여 조절될 가능성을 보여주고 있음을 의미한다.

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