| pyrimidine-nucleoside phosphorylase | |
| Ec Number: | 2.4.2.2 |
| Cas Number: | 9055-35-0 |
| Go Code: | 0016154 |
In enzymology, a pyrimidine-nucleoside phosphorylase is an enzyme that catalyzes the chemical reaction
a pyrimidine nucleoside + phosphate
\rightleftharpoons
Thus, the two substrates of this enzyme are pyrimidine nucleoside and phosphate, whereas its two products are pyrimidine base and alpha-D-ribose 1-phosphate.
This enzyme belongs to the family of glycosyltransferases, specifically the pentosyltransferases. The systematic name of this enzyme class is pyrimidine-nucleoside:phosphate alpha-D-ribosyltransferase. This enzyme is also called Py-NPase. This enzyme participates in pyrimidine metabolism.
As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes and .