Galactose is a monosachride?
We can say that :
Galactose is a(ose) of the family of ; it has six of , so it is a hexose and there is a group at one end, hence the term “aldohexose”.
In the diet, galactose exists as(D: ). Galactose is one of two monosaccharides that make up , a milk .
Theof a of releases a galactose molecule and a .
Glucose and galactose have the same chemical formula (C 6 H 12 O 6 ), they are epimers; they differ in their configuration in space: at the C4 carbon level, the OH group is not arranged in the same way.
Metabolism of galactose in the cell
In the cell, galactose can not be used directly by theof to produce because they require .
Galactose is therefore firstto galactose-1-phosphate. Then it reacts with a molecule of UDP-glucose in the following reaction catalyzed by galactose-1-phosphate uridylyltransferase (GALT):
Galactose-1-phosphate + UDP-glucose -> glucose-1-phosphate (G1P) + UDP-galactose (UDP-Gal)
G1P is then converted to(G6P) through the intervention of the phosphoglucomutase .
G6P can then be used for energy-producing glycolysis for the cell. For its part, the UDP-Gal is recycled to UDP-glucose, by a reaction catalyzed by the enzyme UDP-galactose-4-epimerase, in the presence of NAD + . This UDP-glucose can again react with another molecule of galactose-1-phosphate.
Theis a in which galactose can not be converted into glucose. This severe metabolic disease leads to mental retardation, severe damage , and even death in the neonatal period. It is often due to a deficiency of the enzyme GALT.
Because of thisdeficiency , galactose accumulates in the blood. A mild form of galactosemia promotes . The treatment of galactosemia requires a diet without galactose.