piruvat

Piruvat, known in English as pyruvate, is a three-carbon alpha-keto carboxylate that functions as a central metabolic intermediate. In physiological pH it exists mainly as the pyruvate anion (CH3-CO-COO−), the deprotonated form of pyruvic acid (HOOC-CO-CH3). It is produced primarily by glycolysis in the cytosol, where glucose metabolism yields two molecules of pyruvate per molecule of glucose.

In aerobic conditions, pyruvate is transported into mitochondria and converted by the pyruvate dehydrogenase complex into acetyl-CoA and carbon dioxide, with the reduction of NAD+ to NADH. Acetyl-CoA then enters the citric acid cycle, contributing to further energy production. In anaerobic conditions, pyruvate is reduced to lactate by lactate dehydrogenase, regenerating NAD+ needed for glycolysis to continue. Pyruvate also serves as a branch point for anaplerotic and gluconeogenic pathways: it can be carboxylated to oxaloacetate by pyruvate carboxylase, helping replenish TCA cycle intermediates and providing a substrate for gluconeogenesis through subsequent steps.

Beyond energy metabolism, pyruvate participates in several biosynthetic routes. It acts as a precursor for amino acid synthesis in some organisms and participates in various fermentation processes. In clinical contexts, defects affecting pyruvate metabolism—such as pyruvate dehydrogenase deficiency—can lead to metabolic disorders characterized by lactic acidosis and neurological symptoms. Pyruvate and its salts are also encountered in nutritional and industrial applications, where they are used as intermediates or supplements in certain formulations.