ATPase

(noun)

a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion, releasing energy that is often harnessed to drive other chemical reactions

Related Terms

Examples of ATPase in the following topics:

  • Sodium Pumps as an Alternative to Proton Pumps

    • Na+/K+-ATPase (Sodium-potassium adenosine triphosphatase, also known as Na+/K+ pump, sodium-potassium pump, or sodium pump) is an antiporter enzyme (EC 3.6.3.9) (an electrogenic transmembrane ATPase) located in the plasma membrane of all animal cells.
    • The Na+/K+-ATPase helps maintain resting potential, avail transport and regulate cellular volume.
    • In most animal cells, the Na+/K+-ATPase is responsible for about 1/5 of the cell's energy expenditure.
    • For neurons, the Na+/K+-ATPase can be responsible for up to 2/3 of the cell's energy expenditure.

  • F10 ATP Synthase

    • They were originally called elementary particles and were thought to contain the entire respiratory apparatus of the mitochondrion, but, through a long series of experiments, Ephraim Racker and his colleagues (who first isolated the F1 particle in 1961) were able to show that this particle is correlated with ATPase activity in uncoupled mitochondria and with the ATPase activity in submitochondrial particles created by exposing mitochondria to ultrasound.
    • This ATPase activity was further associated with the creation of ATP by a long series of experiments in many laboratories.

  • Electrochemical Gradient

    • Some examples of pumps for active transport are Na+-K+ ATPase, which carries sodium and potassium ions, and H+-K+ ATPase, which carries hydrogen and potassium ions.
    • Two other carrier protein pumps are Ca2+ ATPase and H+ ATPase, which carry only calcium and only hydrogen ions, respectively.

  • Tubular Reabsorption

    • Active Transport-membrane bound ATPase pumps (such as NA+/K+ ATPase pumps) with carrier proteins carry substances across the plasma membranes of the kidney epithelial cells by consuming ATP.

  • Primary Active Transport

    • One of the most important pumps in animals cells is the sodium-potassium pump (Na+-K+ ATPase), which maintains the electrochemical gradient (and the correct concentrations of Na+ and K+) in living cells.
    • The Na+-K+ ATPase exists in two forms, depending on its orientation to the interior or exterior of the cell and its affinity for either sodium or potassium ions.

  • ATP and Muscle Contraction

    • The ATP is hydrolyzed into ADP and inorganic phosphate (Pi) by the enzyme ATPase.

  • Renal Clearance

    • This variable is sometimes altered through changes in the expression of ATPase pumps involved in active transport.

  • Tubular Secretion

    • Active transport-movement of molecules via ATPase pumps, that transport the substance through the renal epithelial cell into the lumen of the nephron.

  • Overview of Motor Integration

  • Regulation of Urine Concentration and Volume

    • Many medications are diuretics by inhibiting the ATPase pumps, thus inhibiting water reabsorption further.