Galactose-6-phosphate

Activity of Galactose-1-phosphate Uridyl Transferase in Human Liver and Red Blood Cells ... 

G5. Ginsburg, V., and Neufeld, E. F., Inhibition of phosphoglucomutase by galactose-1-phosphate. A possible factor in galactose toxicity. Am. Chem. Soc., 132nd Meeting, New York, N.Y., 1957, p. 27C. 

Once transported into tissues, galactose is phosphorylated (galactokinase), trapping it in the cell. Galactose 1-phosphate is converted to glucose 1-phosphate by galactose 1-P uridyltrans-ferase and an epimerase. The pathway is shown in Figure 1-12-5 important enzymes to remember are ... 

Deficiency of galactose 1-phosphate uridyltransferase produces a more severe disease because, in addition to galactosemia, galactose 1-P accumulates in the liver, brain, and other tissues. The two enzyme deficiencies are compared in Table 1-12-3. 

Galactokinase Deficiency Galactose 1-Phosphate Uridyltransferase Deflcieucy... 

Galactose 1-phosphate uridyl transferase deficiency (galactosemia)... 

This enzyme [EC 2.7.1.6] catalyzes the reaction of ATP with D-galactose to produce ADP and D-galactose 1-phosphate. o-Galactosamine can also act as the substrate. 

This enzyme [EC 2.7.7.10], also known as UTP hexose-1-phosphate uridylyltransferase, catalyzes the reaction of UTP with a-D-galactose 1-phosphate to produce UDP-galactose and pyrophosphate (or, diphosphate), a-o-Glucose 1-phosphate can also function as a substrate, albeit not as effectively. 

In the cell, galactose is converted to galactose 1-phosphate by galactokinase with ATP as the phosphate donor. 

Galactose 1-phosphate and UDP-glucose react to form UDP-galactose and glucose 1-phosphate, as catalyzed by galactose 1-phosphate uridyltransferase. 

Classic galactosemia is a rare, autosomal recessive disorder caused by deficiency of galactose 1-phosphate uridyltransferase. 

Galactose 1-phosphate uridyl transferase Galactosemia, vomiting, hepatomegaly, jaundice, cataracts, amino aciduria, failure to thrive long-term complications exist even with early diagnosis and treatment... 

Elevated in deficiencies of galactokinase, galactose-1-phosphate uridyltransferase (classical galactosemia), UDP galactose-4-epimerase, and Fanconi-Bickel-syn drome, portocaval shunt, and cirrhosis, depending on time after lactose consumption. 

---