Bisphosphoglycerate mutase catalyzes formation of 2,3 bisphosphoglycerate from 1,3 bisphosphoglycerate. This reaction is important for maintaining the 3-phosphyglycerate mutase reaction.

2,3-bisphosphoglycerate is formed both by phosphoglycerate mutase (transiently) and bisphosphpglycerate mutase. 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.