UTP—hexose-1-phosphate uridylyltransferase

In enzymology, an UTP—hexose-1-phosphate uridylyltransferase is an enzyme that catalyzes the chemical reaction


 * UTP + alpha-D-galactose 1-phosphate $$\rightleftharpoons$$ diphosphate + UDP-galactose

Thus, the two substrates of this enzyme are UTP and alpha-D-galactose 1-phosphate, whereas its two products are diphosphate and UDP-galactose.

Enzyme family
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is UTP:alpha-D-hexose-1-phosphate uridylyltransferase. Other names in common use include galactose-1-phosphate uridylyltransferase, galactose 1-phosphate uridylyltransferase, alpha-D-galactose 1-phosphate uridylyltransferase, galactose 1-phosphate uridyltransferase, UDPgalactose pyrophosphorylase, uridine diphosphate galactose pyrophosphorylase, and uridine diphosphogalactose pyrophosphorylase. This enzyme participates in galactose metabolism and nucleotide sugars metabolism.

Structural studies
, 3 structures have been solved for this class of enzymes, with PDB accession codes, , and.