Electrogenic

Electrogenic refers to processes or transports in biological systems that generate or contribute to an electrical potential across a membrane by moving a net charge. In physiology, an electrogenic transporter or pump creates an electrical current or alters the membrane potential by transferring more positive charges in one direction than in the opposite direction.

Common examples include:

- Na+/K+-ATPase, which exports three Na+ ions and imports two K+ ions with each ATP hydrolyzed, generating a net outward current and helping establish the resting membrane potential.

- Proton pumps such as H+-ATPase in plant, fungal, and some bacterial membranes, which move H+ ions across the membrane to create a proton motive force and an electrical gradient.

- Electrogenic cotransporters like the Na+-glucose cotransporter (SGLT) in intestinal and renal epithelia, which move Na+ and glucose together; because glucose is neutral, the cycle results in a net positive charge entering the cell and an electrical current.

Electrogenicity also underpins barriers and transport in many tissues. In neurons and muscle cells, electrogenic pumps and transporters contribute to resting potential and excitability. In plants and microbes, electrogenic pumps help drive nutrient uptake and secondary transport. Some specialized tissues, such as electrocytes in electric fish, are organized to generate measurable electrical discharges, a form of electrogenic activity at the tissue level.

Not all ion movements are electrogenic; some transporters move ions in a way that balances charge across the membrane or operate passively without producing a net current. Electrogenic processes are central to bioelectricity, nutrient handling, and signal transduction in living organisms.