Phosphoglucomutase (PGM)

Phosphoglucomutase is an evolutionarily conserved enzyme that catalyzes the reversible interconversion of glucose 1-phosphate and glucose 6-phosphate, a key step in multiple carbohydrate metabolic pathways, particularly glycogenolysis and glycogenesis[1][5][6][8]. The most studied isoform, phosphoglucomutase-1 (PGM1), is essential for maintaining adequate glucose levels and energy supply, and its deficiency causes a rare metabolic disorder characterized by dysregulated glycogen and glucose metabolism[6]. Phosphoglucomutase operates via a mechanism involving a glucose 1,6-bisphosphate intermediate and requires a divalent metal ion (usually magnesium) for activity. Structurally, it consists of four α/β domains and a highly conserved active site containing a phosphorylatable serine residue (Ser116 in rabbit muscle PGM)[1][5]. There are related family members, such as PGM5, which lacks enzymatic activity in humans but may have structural roles in muscle[3][7]. Phosphoglucomutase is considered a potential metabolic therapeutic target due to its critical position in carbohydrate metabolism, though no targeted drugs are currently in clinical use. Disorders involving PGM1 present with symptoms affecting the liver, muscle, and other organs; monitoring PGM activity can serve as a biomarker for certain inborn errors of metabolism[6].

Other names

Phosphoglucomutase-1 (PGM1)PGM1PGM2PGM5 (for family members)alpha-D-phosphohexomutase

Enzyme catalysis (phosphoryl group transfer between glucose 1-phosphate and glucose 6-phosphate), substrate interconversion for metabolic pathways