Pyruvaattikinaasin

Pyruvaattikinaasin, also known as pyruvate kinase, is an enzyme that plays a crucial role in cellular metabolism, particularly in the conversion of pyruvate to phosphoenolpyruvate (PEP) in the glycolytic pathway. This enzyme is found in the cytoplasm of most eukaryotic cells and is essential for the production of ATP, the primary energy currency of the cell. Pyruvate kinase catalyzes the transfer of a phosphate group from phosphoenolpyruvate to ADP, forming ATP and enolpyruvate, which is then converted to pyruvate. The reaction is reversible, allowing for the regulation of ATP levels in the cell. Pyruvate kinase is a homotetramer, consisting of four identical subunits, and its activity is regulated by various factors, including allosteric effectors such as ATP, ADP, and fructose 1,6-bisphosphate. Mutations in the pyruvate kinase gene can lead to inherited metabolic disorders, such as pyruvate kinase deficiency, which can cause symptoms ranging from mild to severe, depending on the specific mutation and its effect on enzyme activity. Pyruvate kinase is also a target for drug development, with several inhibitors currently in clinical trials for the treatment of cancer and other diseases.