What is the role of UDP in galactose?
UDP-galactose is used to build galactose-containing proteins and fats, which play critical roles in chemical signaling, building cellular structures, transporting molecules, and producing energy.
What does UDP-galactose 4-epimerase do?
3.2), also known as UDP-galactose 4-epimerase or GALE, is a homodimeric epimerase found in bacterial, fungal, plant, and mammalian cells. This enzyme performs the final step in the Leloir pathway of galactose metabolism, catalyzing the reversible conversion of UDP-galactose to UDP-glucose.
Does galactose metabolism require UDP?
Metabolism of galactose via enzymes of the Leloir pathway requires UDP-Glc.
What is galactose Epimerase?
Galactosemia is a disorder that affects how the body processes a simple sugar called galactose. A small amount of galactose is present in many foods. It is primarily part of a larger sugar called lactose, which is found in all dairy products and many baby formulas.
What is Epimerase deficiency?
Disease definition. A very rare, moderate to severe form of galactosemia characterized by moderate to severe signs of impaired galactose metabolism.
How does UDP-galactose make lactose?
Lactose is synthesized within the Golgi complex by the transfer of galactose from UDP-galactose to glucose in a reaction that is catalyzed by a complex between β-4-galactosyltransferase-1 and alpha-lactalbumin.
What is the function of epimerase?
Epimerases catalyze the stereochemical inversion of the configuration about an asymmetric carbon atom in a substrate having more than one center of asymmetry, thus interconverting epimers.
What does an epimerase do?
About Epimerase: An isomerase enzyme, epimerase catalyzes the stereochemistry inversion within biological chemicals. They configure an asymmetric carbon atom from a substrate which has more than one center for asymmetry and forms interconverting epimers.
How does UDP-galactose form from UDP-glucose?
UDP-galactose is derived from UDP-glucose by the action of UDP-glucose 4-epimerase (GalE). This enzyme is well known for the conversion of galactose 1-phosphate into glucose 1-phosphate via the Leloir pathway, but apart from that GalE, also another UDP-glucose 4-epimerase (GalE2) exists.
What happens to galactose in the body?
In normal conditions, galactose is quickly and almost completely metabolized to glucose in the liver. Galactose serves as a substrate for cerebrosides, gangliosides and mucoproteins in the brain and nervous system, which supports its neural and immunological role [2,3,6,7].
How is galactose metabolized?
Although glucose is the form of sugar stored as glycogen within cells, galactose is utilized via conversion to glucose, which can then be oxidized in glycolysis or stored as glycogen. Indeed, up to 30% of ingested galactose is incorporated into glycogen.
What causes galactose Epimerase deficiency?
Galactose epimerase deficiency is caused by mutations in the GALE gene (1p36) encoding the UDP-galactose 4-epimerase enzyme .