Pyruvate kinase isoenzyme R (human erythrocyte) (PK-R)

Pyruvate kinase isoenzyme R (PK-R) is the erythrocyte-specific isoform of the enzyme pyruvate kinase, encoded by the PKLR gene. It catalyzes the final, irreversible step of glycolysis: the transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP, forming ATP and pyruvate. In mature red blood cells, which lack mitochondria, PK-R is essential for ATP generation and cell survival. PK-R operates as a homotetramer and is allosterically activated by fructose 1,6-bisphosphate; its activity is subject to regulation by other effectors such as ATP. Mutations in PKLR can cause pyruvate kinase deficiency, leading to nonspherocytic hemolytic anemia, a common hereditary red blood cell disorder. Pharmacological activators, such as mitapivat, aim to restore enzymatic function in affected patients. PK-R function and deficiency are key biomarkers in clinical settings[1][2][4][5][6].

Other names

Erythrocyte pyruvate kinaseRed blood cell pyruvate kinasePKLR (gene/protein symbol)Pyruvate kinase, liver and red blood cell

Allosteric activation of PK-R to enhance enzyme activity, increase ATP production, and improve erythrocyte survival