phosphomannomutase 2

enzyme

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Last updated

July 16, 2026

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Phosphomannomutase 2 (PMM2) is an enzyme that plays a crucial role in a metabolic process called N-glycosylation. This process is essential for the proper synthesis of proteins and lipids within the cytoplasm and endoplasmic reticulum of cells.1

A defect in the PMM2 enzyme leads to the most common form of congenital disorder of glycosylation (CDG), known as CDG type I. CDG is a group of rare diseases that can affect multiple organs, particularly the brain. Symptoms of CDG type I can include low muscle tone, severe developmental delays, seizures, stroke-like episodes, and liver disease. Currently, there is no effective therapy for CDG, although some rare types may respond to mannose treatment.1

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metabolic disease
Congenital disorders of glycosylation
…defect in a mannose-processing enzyme, phosphomannomutase 2, causes the most common form of CDG (type I). Other enzymatic defects have been identified, but the biochemical bases of some CDG subtypes have not yet been determined. The classic form of CDG (type Ia) is characterized by low muscle tone in infancy,…
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…defect in a mannose-processing enzyme, phosphomannomutase 2, causes the most common form of CDG (type I). Other enzymatic defects have been identified, but the biochemical bases of some CDG subtypes have not yet been determined. The classic form of CDG (type Ia) is characterized by low muscle tone in infancy,…
Read More