It is also known as ATP synthase or ATP phosphohydrolase (H +-transporting). It binds to the surface of the pump, and inhibits its dephosphorylation, thus, blocking K + transport into the cell. Ouabain, a cardiac glycoside, is the inhibitor of sodium-potassium ATPase.And the cycle continuously repeats itself. This new change in conformation changes the affinity of the pump from potassium to sodium ions.The phosphate released induces the pump to reassume its earlier confirmation, causing it to re-open inside the cell.Thus, potassium ions bind to it and release the attached phosphate group. Though the conformational change in the pump causes sodium to lose its affinity, it creates a high-affinity environment for potassium ions on the pump.This change allows the pump to lose its affinity towards sodium, thus, releasing the sodium ions to the cell exterior or extracellular area. The chemical modification to the pump due to phosphorylation causes it to undergo a conformational change.When sodium binds to the carrier protein, it induces the phosphorylation of the pump via ATP hydrolysis. ![]()
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