UDPglukosa

UDP-glucose is a vital molecule in biological systems, serving as a key intermediate in carbohydrate metabolism. Its full name is uridine diphosphate glucose. It is a nucleotide sugar, meaning it consists of a nucleoside (uridine) linked to a phosphate group, which is further attached to a glucose molecule. This structure makes UDP-glucose an activated form of glucose, readily available for enzymatic transfer reactions.

The primary role of UDP-glucose is as a donor of glucose units in the synthesis of various polysaccharides. In plants, it is a precursor for the synthesis of sucrose, starch, and cellulose. Sucrose, a major transport sugar in plants, is formed by the transfer of glucose from UDP-glucose to fructose. Starch, the primary storage polysaccharide in plants, is built from UDP-glucose. Cellulose, a structural component of plant cell walls, also utilizes UDP-glucose as its glucose donor.

In animals and fungi, UDP-glucose is involved in the synthesis of glycogen, the storage form of glucose. It also plays a role in the formation of glycosaminoglycans, important components of the extracellular matrix, and in glycosylation reactions, where sugar molecules are attached to proteins and lipids. The interconversion between glucose and UDP-glucose is catalyzed by UDP-glucose pyrophosphorylase, a critical enzyme in maintaining cellular glucose homeostasis and providing the building blocks for essential biomolecules.