fosfoglükomutaz

Phosphoglucomutase, often abbreviated as PGM, is an enzyme that plays a crucial role in carbohydrate metabolism. Specifically, it catalyzes the reversible interconversion of glucose-1-phosphate and glucose-6-phosphate. This isomerization is a key step in both glycogenolysis, the breakdown of glycogen into glucose, and glycolysis, the process of breaking down glucose for energy.

The enzyme requires a cofactor, pyridoxal phosphate (PLP), which is derived from vitamin B6. The reaction mechanism involves a transient phosphorylation of the enzyme itself, followed by the transfer of the phosphate group to the substrate. In the forward reaction, glucose-1-phosphate is converted to glucose-6-phosphate. In the reverse reaction, glucose-6-phosphate is converted to glucose-1-phosphate.

Phosphoglucomutase is found in a wide variety of organisms, from bacteria to humans. In humans, there are several isoforms of the enzyme, with different tissue distributions and roles. For instance, PGM1 is predominantly found in muscle and liver cells, where it is essential for glucose homeostasis. PGM2 is another important isoform. Genetic variations in phosphoglucomutase genes can lead to certain metabolic disorders. The enzyme's activity is tightly regulated to ensure that the cell can appropriately manage its glucose supply and energy demands.