2.4.2.9 uracil phosphoribosyltransferase; UMP pyrophosphorylase; UPRTase; UMP:pyrophosphate phosphoribosyltransferase; uridine 5'-phosphate pyrophosphorylase; uridine monophosphate pyrophosphorylase; uridylate pyrophosphorylase; uridylic pyrophosphorylase