MPI Human

Mannose Phosphate Isomerase (MPI), also known as phosphomannose isomerase (PMI), is an enzyme that plays a crucial role in carbohydrate metabolism. It catalyzes the reversible interconversion of fructose-6-phosphate and mannose-6-phosphate, which is essential for maintaining the supply of D-mannose derivatives required for glycosylation reactions .

MPI belongs to the family of enzymes that convert aldoses and ketoses. Specifically, it facilitates the conversion between fructose-6-phosphate and mannose-6-phosphate. This reaction is vital as mannose-6-phosphate can be used as a precursor for glycan synthesis or catabolized for energy production .

The MPI gene has been cloned from various organisms, and its structure has been determined through crystallization studies. Mutations in the MPI gene can lead to congenital disorders of glycosylation, specifically type Ib (MPI-CDG or CDG-Ib), which is characterized by defects in glycosylation pathways . These mutations can result in severe clinical manifestations, but the condition can be managed by providing exogenous mannose .

Loss of MPI activity is lethal in certain organisms like Saccharomyces cerevisiae, but can be rescued by exogenous mannose supplementation. In humans, MPI deficiency leads to congenital disorders of glycosylation, which can cause a range of symptoms including developmental delays, liver dysfunction, and coagulation abnormalities .

Human recombinant MPI is used in various research and clinical applications. It is crucial for studying glycosylation disorders and developing therapeutic strategies. Additionally, MPI inhibitors are being explored as potential treatments for infections caused by Candida albicans, particularly in immunocompromised patients .