neutral L-amino acid:sodium symporter activity

Definition

Target type: molecularfunction

Enables the transfer of a solute or solutes from one side of a membrane to the other according to the reaction: neutral L-amino acid(out) + Na+(out) = neutral L-amino acid(in) + Na+(in). [TC:2.A.23.3.1]

Neutral L-amino acid:sodium symporter activity involves the transmembrane transport of both neutral L-amino acids and sodium ions across a cell membrane. The process is driven by the electrochemical gradient of sodium ions, which are typically at higher concentrations outside the cell. This gradient is established and maintained by the action of sodium-potassium pumps that actively transport sodium ions out of the cell.

This symporter activity is highly specific for certain L-amino acids, typically those with non-polar side chains such as alanine, leucine, isoleucine, and valine. The symporter protein binds both sodium ions and an L-amino acid substrate simultaneously, facilitating their co-transport across the membrane. This co-transport mechanism ensures that amino acids are transported into the cell only when sodium ions are present, providing a tight regulation of amino acid uptake.

The symporter activity is crucial for the uptake of essential amino acids by cells, which are necessary for protein synthesis, growth, and other vital cellular processes. It is also important for the reabsorption of amino acids from the kidney tubules, preventing their loss in the urine. Mutations in the genes encoding these symporters can lead to various metabolic disorders affecting amino acid transport and metabolism.'
"

Proteins (1)

Compounds (4)