oksaloasetaattia

Oxaloacetate is a four-carbon dicarboxylic acid that plays a crucial role in cellular metabolism. It is an intermediate in the citric acid cycle (also known as the Krebs cycle or TCA cycle), a central pathway for energy production in aerobic organisms. In this cycle, oxaloacetate is regenerated in the final step, allowing it to condense with acetyl-CoA to begin a new round of reactions.

Beyond its role in energy metabolism, oxaloacetate is also involved in gluconeogenesis, the process by which glucose is synthesized from non-carbohydrate precursors. It is a key intermediate in this pathway, linking amino acid and carbohydrate metabolism. Furthermore, oxaloacetate is a substrate for the enzyme aspartate aminotransferase, which is important for amino acid metabolism and the interconversion of amino acids and keto acids.

The synthesis of oxaloacetate primarily occurs through the carboxylation of pyruvate, catalyzed by the enzyme pyruvate carboxylase. This reaction requires ATP and bicarbonate as substrates. Oxaloacetate can also be formed from aspartate through the action of aspartate aminotransferase. Its concentration is tightly regulated, reflecting its pivotal position in various metabolic pathways.