Coupling of Chemical Reaction to Transport of Sodium and Potassium
The membrane bound (Na++K+)-activated ATP hydrolyzing enzyme system (Na++K+ ATPase in the following) couples the flux of sodium and of potassium along their electrochemical gradients across the cell membrane — sive flux — to a flux of the same ions against their electrochemical gradients — the active transport (see Skou, 1975). The coupling is tight enough to give a steady-state concentration of sodium and of potassium in the cell which is away from thermodynamic equilibrium of the two cations.
KeywordsElectrochemical Gradient Adenosine Triphosphatase Sodium Pump Apparent Affinity Active Flux
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