Phosphoglycerate mutase catalyzes the interconversion of 3-phosphoglycerate (3PG) and 2-phosphoglycerate (2PG) in the glycolysis and gluconeogenesis pathways (See Figure).
The mechanism of the reaction catalyzed by phosphoglycerate mutase involves formation of 2,3-bisphosphoglycerate via transient phosphorylation of a histidine residue of the enzyme. 2,3BPG can diffuse from phosphoglycerate mutase, however, leaving the enzyme trapped in an unusable state. Cells make excess 2,3BPG (using the enzyme bisphosphoglycerate mutase) in order to drive 2,3BPG back to phosphoglycerate mutase, so the reaction can go to completion.
Previous step of glycolysis; Next step of glycolysis
1. RasMol Image of Phosphoglycerate Mutase (slow)