succinic acid

A four-carbon dicarboxylic acid with the formula HOOC(CH₂)₂COOH. Succinate is an intermediate in the TCA cycle, formed from suc-cinyl CoA with concomitant formation of GTP. It is oxidized to fumarate by succinate dehydrogenase, a flavoprotein. In the reaction the FAD prosthetic group of succinate dehydrogenase is reduced to FADH₂. Succinate is also a product of the glyoxylate cycle, and succinyl CoA is an important precursor in porphyrin synthesis.