Succinat

Succinat is the dianion of succinic acid (butanedioic acid) and the name used for its salts. The parent acid has formula C4H6O4; when two protons are lost, the dianion appears as C4H4O4^2−. Common salts include disodium succinate Na2C4H4O4 and dipotassium succinate K2C4H4O4. As a dicarboxylate, succinate is typically highly soluble in water.

In metabolism, succinate is an intermediate of the citric acid cycle (TCA or Krebs cycle). It is produced from succinyl-CoA and is oxidized to fumarate by succinate dehydrogenase, a flavin adenine dinucleotide (FAD)-dependent enzyme that feeds electrons into the mitochondrial respiratory chain. Succinate can also participate in various anaplerotic and catabolic pathways that connect to broader energy metabolism.

Biologically, succinate has roles beyond being a metabolic intermediate. It can act as a signaling molecule through the G protein-coupled receptor SUCNR1 (also known as GPR91), influencing processes such as renin release, adipose tissue function, and certain innate immune responses. This signaling function links cellular metabolism to systemic physiological responses.

Applications and occurrence: succinate and its salts are used as buffering agents and dietary supplements in some foods and pharmaceutical preparations. They are also employed as sources of succinate in laboratory buffer solutions and in certain fermentation and biotechnological processes.

See also: succinate dehydrogenase; citric acid cycle; SUCNR1 receptor.