Glukose1phosphat

Glukose1phosphat, more commonly known as glucose-1-phosphate (G1P), is a monosaccharide phosphate in which a phosphate group is attached to the anomeric carbon of glucose. Its chemical formula is C6H13O9P, and its molecular weight is about 260 g/mol. In solution, glucose-1-phosphate can exist as α- or β-D-glucose-1-phosphate and serves as an important metabolic intermediate.

Occurrence and production

In animals, glucose-1-phosphate is produced during glycogenolysis when glycogen phosphorylase cleaves glycogen, releasing glucose-1-phosphate. It can be rapidly interconverted to glucose-6-phosphate by the enzyme phosphoglucomutase, linking glycogen breakdown to central carbon metabolism. Glucose-6-phosphate may then enter glycolysis, the pentose phosphate pathway, or be dephosphorylated to free glucose in tissues that express glucose-6-phosphatase, such as the liver.

Metabolic roles and pathways

Glucose-1-phosphate acts as a branch point between energy production and biosynthesis. Through UDP-glucose pyrophosphorylase, G1P reacts with UTP to form UDP-glucose and pyrophosphate. UDP-glucose is the activated glucose donor used by glycogen synthase to extend glycogen chains and also participates in other biosynthetic processes, including cell-wall and polysaccharide biosynthesis in plants and microbes.

Summary

Glucose-1-phosphate is a key intermediate that connects glycogen breakdown with glycolysis and energy production, while also supplying activated sugars for glycogen synthesis and other biosynthetic pathways. Its metabolism exemplifies the integration of carbohydrate storage, energy generation, and biosynthesis in cells.