Succinic acid

Succinic acid (/səkˈsɪnɪk/) is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. The name derives from Latin succinum, meaning amber. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological roles as a metabolic intermediate being converted into fumarate by the enzyme succinate dehydrogenase in complex 2 of the electron transport chain which is involved in making ATP, and as a signaling molecule reflecting the cellular metabolic state. It is marketed as food additive E363. Succinate is generated in mitochondria via the tricarboxylic acid cycle (TCA). Succinate can exit the mitochondrial matrix and function in the cytoplasm as well as the extracellular space, changing gene expression patterns, modulating epigenetic landscape or demonstrating hormone-like signaling. As such, succinate links cellular metabolism, especially ATP formation, to the regulation of cellular function. Dysregulation of succinate synthesis, and therefore ATP synthesis, happens in some genetic mitochondrial diseases, such as Leigh syndrome, and Melas syndrome, and degradation can lead to pathological conditions, such as malignant transformation, inflammation and tissue injury.Acetyl-CoAOxaloacetateMalateFumarateSuccinateSuccinyl-CoACitratecis-AconitateIsocitrateOxalosuccinate2-oxoglutarate Succinic acid (/səkˈsɪnɪk/) is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. The name derives from Latin succinum, meaning amber. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological roles as a metabolic intermediate being converted into fumarate by the enzyme succinate dehydrogenase in complex 2 of the electron transport chain which is involved in making ATP, and as a signaling molecule reflecting the cellular metabolic state. It is marketed as food additive E363. Succinate is generated in mitochondria via the tricarboxylic acid cycle (TCA). Succinate can exit the mitochondrial matrix and function in the cytoplasm as well as the extracellular space, changing gene expression patterns, modulating epigenetic landscape or demonstrating hormone-like signaling. As such, succinate links cellular metabolism, especially ATP formation, to the regulation of cellular function. Dysregulation of succinate synthesis, and therefore ATP synthesis, happens in some genetic mitochondrial diseases, such as Leigh syndrome, and Melas syndrome, and degradation can lead to pathological conditions, such as malignant transformation, inflammation and tissue injury. Succinic acid is a white, odorless solid with a highly acidic taste. In an aqueous solution, succinic acid readily ionizes to form its conjugate base, succinate (/ˈsʌksɪneɪt/). As a diprotic acid, succinic acid undergoes two successive deprotonation reactions: The pKa of these processes are 4.3 and 5.6, respectively. Both anions are colorless and can be isolated as the salts, e.g., Na(CH2)2(CO2H)(CO2) and Na2(CH2)2(CO2)22−. In living organisms, primarily succinate, not succinic acid, is found. As a radical group it is called a succinyl (/ˈsʌksɪnəl/) group. Like most simple mono- and dicarboxylic acids, it is not harmful but can be an irritant to skin and eyes. Succinic acid can be oxidized to fumaric acid or be converted to diesters, such as diethylsuccinate (CH2CO2CH2CH3)2. This diethyl ester is a substrate in the Stobbe condensation. Dehydration of succinic acid gives succinic anhydride. Succinate can be used to derive 1,4-butanediol, maleic anhydride, succinimide, 2-pyrrolidinone and tetrahydrofuran. Historically, succinic acid was obtained from amber by distillation and has thus been known as spirit of amber. Today, succinic acid is generated for human use synthetically or converted from biomass via fermentation. Common industrial routes of synthesis include partial hydrogenation of maleic acid, oxidation of 1,4-butanediol, and carbonylation of ethylene glycol. Succinate is also produced petrochemically from butane via maleic anhydride. Additionally, genetic engineering of microorganisms, such as Escherichia coli or Saccharomyces cerevisiae, has recently allowed for the high-yielding, commercial production from fermentation of glucose. Global production is estimated at 16,000 to 30,000 tons a year, with an annual growth rate of 10%. In 2004, succinate was placed on the US Department of Energy's list of top 12 platform chemicals from biomass. Succinic acid is a precursor to some polyesters and a component of some alkyd resins. 1,4-Butanediol (BDO) can be synthesized using succinic as a precursor. The automotive and electronics industries heavily rely on BDO to produce connectors, insulators, wheel covers, gearshift knobs and reinforcing beams. Succinic acid also serves as the bases of certain biodegradable polymers, which are of interest in tissue engineering applications.