uridylate synthase is a bifunctional protein that first forms orotidine 5'-phosphate ( omp ) from orotate via its orotate phosphoribosyltransferase activity ( ec 2.4.2.10 ) and then converts omp to uridine 5'-phosphate ( ump ) via the omp decarboxylase activity ( ec 4.1.1.23 ) .
C0041921
uridine
C0042002
ump