Na⁺/K⁺-ATPase (also known as the Na⁺/K⁺ pump or Na⁺/K⁺ exchanger) is an enzyme (EC 3.6.3.9) located in the plasma membrane (specifically an electrogenic transmembrane ATPase). It is found in the plasma membrane of virtually every human cell and is common to all cellular life. It helps maintain cell potential and regulate cellular volume. Ribbon diagram of the catalytically perfect enzyme TIM. An enzyme is a protein that catalyzes, or speeds up, a chemical reaction. ... EC numbers (Enzyme Commission numbers) are a numerical classification scheme for enzymes, based on the chemical reactions they catalyze. ... Drawing of a cell membrane A component of every biological cell, the cell membrane (or plasma membrane) is a thin and structured bilayer of phospholipid and protein molecules that envelopes the cell. ... ATPases are a class of enzymes that catalyze the decomposition of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and a free phosphate ion. ... Binomial name Homo sapiens Linnaeus, 1758 Subspecies Homo sapiens idaltu(extinct) Homo sapiens sapiens Homo (genus). ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... Life is a multi-faceted concept. ... In biological cells that are electrically at rest, the cytosol possesses a uniform electric potential or voltage compared to the extracellular solution. ... Volume, also called capacity, is a quantification of how much space an object occupies. ...

Function

In order to maintain the cell potential, cells must keep a low concentration of sodium ions and high levels of potassium ions within the cell (intracellular). Outside cells (extracellular), there are high concentrations of sodium and low concentrations of potassium, so diffusion occurs through ion channels in the plasma membrane. In order to keep the appropriate concentrations, the sodium-potassium pump pumps sodium out and potassium in. General Name, Symbol, Number sodium, Na, 11 Chemical series alkali metals Group, Period, Block 1, 3, s Appearance silvery white Atomic mass 22. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ... In cell biology, molecular biology and related fields, the word intracellular means inside the cell. It is used in contrast to extracellular (outside the cell). ... In cell biology, molecular biology and related fields, the word extracellular means outside the cell. It is used in contrast to intracellular (inside the cell). ... Diffusion, being the spontaneous spreading of matter (particles), heat, or momentum, is one type of transport phenomena. ... Another, unrelated ion channeling process is part of ion implantation. ...

The mechanism is:

• The pump, with bound ATP, binds 3 intracellular Na⁺ ions.
• ATP is hydrolyzed, leading to phosphorylation of the pump at a highly conserved aspartate residue and subsequent release of ADP.
• A conformational change in the pump exposes the Na⁺ ions to the outside. The phosphorylated form of the pump has a low affinity for sodium ions, so they are released.
• The pump binds 2 extracellular K⁺ ions, leading to the dephosphorylation of the pump.
• ATP binds, and the pump reorients to release potassium ions inside the cell so the pump is ready to go again.

Adenosine 5-triphosphate (ATP) is the nucleotide known in biochemistry as the molecular currency of intracellular energy transfer; that is, ATP is able to store and transport chemical energy within cells. ... NA may stand for: Namibia (ISO country code) Narcotics Anonymous National Association (denoted as N.A.) National Association of Professional Baseball Players North America Northern Alliance Nucleic Acid Numerical Aperture - A specification in photolithographic tools. ... ... Hydrolysis is a chemical process in which a molecule is cleaved into two parts by the addition of a molecule of water. ... Phosphorylation is the addition of a phosphate (PO4) group to a protein or a small molecule. ... Adenosine diphosphate, abbreviated ADP, is a nucleotide. ... General Name, Symbol, Number potassium, K, 19 Chemical series alkali metals Group, Period, Block 1, 4, s Appearance silvery white Atomic mass 39. ...

Physiology

As the plasma membrane is far less permeable to sodium than it is to potassium ions, an electric potential (negative intracellularly) is the eventual result.

The electrical and concentration gradient established by the sodium-potassium ATPase supports not only the cell resting potential but the action potentials of nerves and muscles. Export of sodium from the cell provides the driving force for several facilitated transporters, which import glucose, amino acids and other nutrients into the cell. Translocation of sodium from one side of an epithelium to the other side creates an osmotic gradient that drives the absorption of water. In biological cells that are electrically at rest, the cytosol possesses a uniform electric potential or voltage compared to the extracellular solution. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... Nerves (yellow)    Nerves redirects here. ... A top-down view of skeletal muscle Muscle is a contractile form of tissue. ... Glucose (Glc), a simple monosaccharide sugar, is one of the most important carbohydrates and is used as a source of energy in animals. ... In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ...

Another important task of the Na-K pump is to provide a Na gradient that is used by certain carrier processes. In the gut, for example, sodium is transported out of the resorbing cell on the blood side via the Na-K pump, whereas, on the resorbing side, the Na-Glucose co-transporter uses the created Na gradient as a source of energy to import both Na and Glucose, which is far more efficient than simple diffusion. Similar processes are located in the renal tubular system. yes that is basically it For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... Nephron of the kidney A nephron is the basic structural and functional unit of the kidney. ...

Pharmacology

The Na-K pump found in the membrane of heart cells is an important target of cardiac glycosides (for example digoxin and ouabain), drugs used to improve heart performance by increasing its force of contraction. Contraction of any muscle is dependent on a 100- to 10,000-times higher-than-normal intercellular Ca concentration, which, as soon as it is put back again on its normal level by a carrier enzyme in the plasma membrane, will relax this muscle. Since this carrier enzyme (Na-Ca translocator) uses the Na gradient generated by the Na-K pump to remove Ca from the intercellular space, slowing down the Na-K pump results in a permanently-higher Ca level in the muscle, which will eventually lead to stronger contractions. Cardiac glycosides are drugs used in the treatment of congestive heart failure and cardiac arrhythmia. ... Digoxin is a cardiac glycoside extracted from the foxglove plant, digitalis. ... Ouabain is the familiar name of g-strophanthin, a poisonous cardiac glycoside. ... The heart and lungs (from an older edition of Grays Anatomy) The heart (Latin cor) is a hollow, muscular organ that pumps blood through the blood vessels by repeated, rhythmic contractions. ... Calcium plays a vital role in the anatomy, physiology and biochemistry of organisms and of the cell, particularly in signal transduction pathways. ... A top-down view of skeletal muscle Muscle is a contractile form of tissue. ...

Discovery

Na⁺/K⁺-ATPase was discovered by Jens Christian Skou in 1957. He published his work in Biochimica et Biophysica Acta (vol. 23, pp. 394-401) in a paper entitled "The Influence of some Cations on an Adenosine Triphosphatase from Peripheral Nerves". At the time he was an assistant professor at the Department of Physiology, University of Aarhus, Denmark . Jens Christian Skou (born October 8, 1918) is a Danish chemist and Nobel laureate. ... 1957 (MCMLVII) was a common year starting on Tuesday of the Gregorian calendar. ... University of Aarhus The University of Aarhus is a university based in Ã…rhus, Denmark. ...

In 1997, for this discovery, he received the Nobel Prize in Chemistry (jointly awarded with Paul D. Boyer, John E. Walker for their work on the "enzymatic mechanism underlying the synthesis of adenosine triphosphate"). 1997 (MCMXCVII) is a common year starting on Wednesday of the Gregorian calendar. ... This is a list of Nobel Prize laureates in Chemistry from 1901 to the present day. ... Paul Delos Boyer (born July 31, 1918) is an American biochemist. ... John Ernest Walker (born January 7, 1941) is an English chemist. ...

See also

• active transport

Active transport is the mediated transport of biochemicals, and other atomic/molecular substances, across membranes. ...

References