uridine 5'-phosphate ( ump ) synthase contains two sequential catalytic activities for the synthesis of orotidine 5'-phosphate ( omp ) from orotate ( ec 2.4.2.10 , orotate phosphoribosyltransferase ) and the decarboxylation of omp to form ump ( ec 4.1.1.23 , omp decarboxylase ) .
C0041921
uridine
C0042002
ump