yana-notes

Na+K+ ATPase

links: Enzyme reference: 6-12-2021

Na+/K+-ATPase or Sodium-Potassium Pump #

Sodium-potassium adenosine triphosphatase. Gilbert Ling says it’s fake news.

  • Uses the energy of ATP hydrolysis to actively transport, in each cycle, 3 Na+ out of the cell, and 2 K+ into it.
  • In most neurons, the concentration of K+ is higher inside, and Na+ is higher oustide.

I’m hearing multiple stories here… Wikipedia, which cites Guyton (2006) has a different order. Gilbert - help me out.

  1. 3 $\ce{Na+}$ ions bind, by which a conformational change occurs where ATP binds to it, and hydrolyzes.
  2. The affinity changes from Na+ to K+. the 3 $\ce{Na+}$ dissociates into the extracellular fluid, and 2 $\ce{K+}$ binds.
  3. The bound phosphate dissociates, and the pump reverts to the original conformation whereby 2 $\ce{K+}$ dissociates into the cell interior.