• Cholesterol depletion inhibits Na+,K+-ATPase activity in a near-native membrane environment 

      Garcia, Alvaro; Lev, Bogdan; Hossain, Khondker R.; Gorman, Amy; Diaz, Dil; Pham, T. H. Nguyen; Cornelius, Flemming; Allen, Toby W.; Clarke, Ronald J.
      Published 2019-02-15
      Cholesterol’s effects on Na+,K+-ATPase reconstituted in phospholipid vesicles have been extensively studied. However, previous studies have reported both cholesterol-mediated stimulation and inhibition of Na+,K+-ATPase ...
      Open Access
      Article
    • Dipole-potential-mediated effects on ion pump kinetics 

      Clarke, Ronald J.
      Published 2015-10-01
      The kinetics of conformational changes of P-type ATPases necessary for the occlusion or de-occlusion of transported ions are known to be sensitive to the composition of the surrounding membrane, e.g. phospholipid content, ...
      Open Access
      Publisher version
    • Effect of cholesterol on the dipole potential of lipid membranes 

      Clarke, Ronald J.
      Published 2019-01-01
      The membrane dipole potential, ψd, is an electrical potential difference with a value typically in the range 150 – 350 mV (positive in the membrane interior) which is located in the lipid headgroup region of the membrane, ...
      Open Access
      Article
    • Electrostatic stabilization plays a central role in autoinhibitory regulation of the Na+,K+-ATPase 

      Jiang, Qiucen; Garcia, Alvaro; Han, Minwoo; Cornelius, Flemming; Apell, Hans-Jurgen; Khandelia, Himanshu; Clarke, Ronald J.
      Published 2017-01-24
      The Na+,K+-ATPase is present in the plasma membrane of all animal cells. It plays a crucial role in maintaining the Na+ and K+ electrochemical potential gradients across the membrane, which are essential in numerous ...
      Open Access
      Article
    • Evidence for ATP interaction with phosphatidylcholine bilayers 

      Garcia, Alvaro; Pochinda, Simon; Elgaard-Jorgensen, Paninnguaq N.; Khandelia, Himanshu; Clarke, Ronald J.
      Published 2019-07-10
      ATP is a fundamental intracellular molecule and is thought to diffuse freely throughout the cytosol. Evidence obtained from nucleoside-sensing sarcolemmal ion channels and red blood cells, however, suggest that ATP is ...
      Open Access
      Article
    • Evolutionary analysis of the lysine-rich N-terminal cytoplasmic domains of the gastric H+,K+-ATPase and the Na+,K+-ATPase 

      Diaz, Dil; Clarke, Ronald J.
      Published 2018-07-28
      The catalytic α-subunits of both the Na+,K+-ATPase and the gastric H+,K+-ATPase possess lysine-rich N-termini which project into the cytoplasm. Due to conflicting experimental results it is currently unclear whether the ...
      Open Access
      Article
    • Extracellular allosteric Na+ binding to the Na+,K+-ATPase in cardiac myocytes 

      Garcia, Alvaro; Fry, Natasha A. S.; Karimi, Keyvan; Liu, Chia-chi; Apell, Hans-Jurgen; Rasmussen, Helge H.; Clarke, Ronald J.
      Published 2013-12-01
      Whole cell patch clamp measurements of the current, Ip, produced by the Na+,K+-ATPase across the plasma membrane of rabbit cardiac myocytes show an increase in Ip over the extracellular Na+ concentration range 0 – 50 mM. ...
      Open Access
      Article
    • General and specific interactions of the phospholipid bilayer with P-type ATPases 

      Hossain, Khondker R.; Clarke, Ronald J.
      Published 2019-05-09
      Protein structure and function are modulated via interactions with their environment, representing both the surrounding aqueous media and lipid membranes that have an active role in shaping the structural topology of ...
      Open Access
      Article
    • Glutathionylation-dependence of N+-K+-pump currents can mimic reduced subsarcolemmal Na+ diffusion 

      Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J.; Rasmussen, Helge H.
      Published 2016-03-01
      The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on re-exposure of myocytes to K+ ...
      Open Access
      Article
    • Identification of electric-field-dependent steps in the Na+,K+-pump cycle 

      Mares, Laura J.; Garcia, Alvaro; Rasmussen, Helge H.; Cornelius, Flemming; Mahmmoud, Yasser A.; Berlin, Joshua R.; Lev, Bogdan; Allen, Toby W.; Clarke, Ronald J.
      Published 2014-09-01
      The charge transporting activity of the Na+,K+-ATPase depends on its surrounding electric field. To isolate which steps of the enzyme’s reaction cycle involve charge movement we have investigated the response of the ...
      Open Access
      Article
    • Interaction of N-terminal peptide analogues of the Na+,K+-ATPase with membranes 

      Nguyen, Khoa; Garcia, Alvaro; Sani, Marc-Antoine; Diaz, Dil; Dubey, Vikas; Clayton, Daniel; Dal Poggetto, Giovanni; Cornelius, Flemming; Payne, Richard J.; Separovic, Frances; Khandelia, Himanshu; Clarke, Ronald J.
      Published 2018-03-06
      The Na+,K+-ATPase, which is present in the plasma membrane of all animal cells, plays a crucial role in maintaining the Na+ and K+ electrochemical potential gradients across the membrane. Recent studies have suggested that ...
      Open Access
      Article
    • Introduction 

      Khalid, Mohammed A. A.; Clarke, Ronald J.
      Published 2015-01-01
      Open Access
      Book chapter
    • Kinetic contribution to extracellular Na+/K+ selectivity in the Na+/K+ pump 

      Vleeskens, Elizabeth; Clarke, Ronald J.
      Published 2018-03-01
      The sodium potassium pump (Na+,K+-ATPase) shows a high selectivity for K+ over Na+ binding from the extracellular medium. To understand the K+ selectivity in the presence of a high concentration of competing Na+ ions ...
      Open Access
      Article, Letter
    • Membrane accessibility of glutathione 

      Garcia, Alvaro; Eljack, Nasma D.; Sani, Marc-Antoine; Separovic, Frances; Rasmussen, Helge H.; Kopec, Wojciech; Khandelia, Himanshu; Cornelius, Flemming; Clarke, Ronald J.
      Published 2015-07-30
      Regulation of the ion pumping activity of the Na+,K+-ATPase is crucial to the survival of animal cells. Recent evidence has suggested that the activity of the enzyme could be controlled by glutathionylation of cysteine ...
      Open Access
      Article
    • Polar interactions play an important role in the energetics of the main phase transition of phosphatidylcholine membranes 

      Garcia, Alvaro; Zou, Haipei; Hossain, Khondker R.; Xu, Qikui Henry; Buda, Annabelle; Clarke, Ronald J.
      Published 2019-01-08
      Conformational changes of membrane proteins are accompanied by deformation in the surrounding lipid bilayer. To gain insight into the energetics of membrane deformation, the phase behavior of dimyristoylphosphatidylcholine ...
      Open Access
      Article
    • Quantitative calculation of the role of the Na+,K+-ATPase in thermogenesis 

      Clarke, Ronald J.; Catauro, Michelina; Rasmussen, Helge H.; Apell, Hans-Jurgen
      Published 2013-07-11
      The Na+,K+-ATPase is accepted as an important source of heat generation (thermogenesis) in animals. Based on information gained on the kinetics of the enzyme’s partial reactions we consider via computer simulation whether ...
      Open Access
      Article
    • Redox-dependent regulation of the Na+-K+ pump: New twists to an old target for treatment of heart failure 

      Liu, Chia-Chi; Fry, Natasha A. S.; Hamilton, Elisha J.; Chia, Karin K. M.; Garcia, Alvaro; Galougahi, Keyvan K.; Figtree, Gemma A.; Clarke, Ronald J.; Bundgaard, Henning; Rasmussen, Helge H.
      Published 2013-05-30
      By the time it was appreciated that the positive inotropic effect of cardiac glycosides is due to inhibition of the membrane Na+-K+ pump, glycosides had been used for treatment of heart failure on an empiric basis for ~200 ...
      Open Access
      Article
    • Stimulation of Na+,K+-ATPase activity as a possible driving foce in cholesterol evolution 

      Lambropoulos, Nicholas; Garcia, Alvaro; Clarke, Ronald J.
      Published 2015-12-29
      Cholesterol is exclusively produced by animals and is present in the plasma membrane of all animal cells. In contrast, the membranes of fungi and plants contain other sterols. To explain the exclusive preference of animal ...
      Open Access
      Article
    • Stopped-flow fluorimetry using voltage-sensitive fluorescent membrane probes 

      Clarke, Ronald J.; Khalid, Mohammed A. A.
      Published 2015-01-01
      Open Access
      Book chapter
    • Supramolecular beta-cyclodextrin adducts of boron-rich DNA metallointercalators containing dicarba-closo-dodecaborane 

      Ching, H. Y. Vincent; Clarke, Ronald J.; Rendina, Louis M.
      Published 2013-08-28
      A chiral, isomeric series of novel boron-rich PtII metallointercalators ([PtL2(phen)](NO3)2: L = (x)-(1,y-closo-carboran-1-yl)pyrid-z-ylmethanol: x = R, S; y = 7, 12; z = 3, 4) wre prepared and fully characterized. By means ...
      Open Access
      Article