betaDglukoz

Beta-D-glucose, or β-D-glucose, is the beta anomer of the aldohexose D-glucose. In its cyclic form it is typically the beta-D-glucopyranose, a six-membered ring created when the aldehyde group at C1 reacts with the hydroxyl on C5. The D designation refers to the configuration of the chiral center farthest from the carbonyl, and the beta designation specifies the orientation of the anomeric hydroxyl on C1.

In solution, glucose exists in a dynamic equilibrium between the open-chain form and cyclic forms, and between the alpha and beta anomers. Mutarotation rapidly interconverts α-D-glucose and β-D-glucose, and at equilibrium in water about 64% is the beta form and about 36% is the alpha form. Enzymes called mutarotases can accelerate this interconversion in some organisms.

Beta-D-glucose is a fundamental building block in biochemistry. It is a common circulating sugar and a key substrate in intermediary metabolism. Its monomeric form is also the subunit used to construct cellulose through β-1,4 glycosidic bonds, a major structural polymer in plants. By contrast, starch and glycogen are polymers of α-D-glucose linked by α-1,4 and α-1,6 bonds, which account for their different properties.

Chemically, β-D-glucose and α-D-glucose share the same molecular formula (C6H12O6) and many chemical properties, but differ in the stereochemistry at the anomeric carbon. In biochemical processes, glucose is typically metabolized after phosphorylation to glucose-6-phosphate, and subsequent isomerization feeds into central pathways such as glycolysis.