uracil phosphoribosyltransferase -->
medical dictionary

One of a group of enzymes (EC sub-subclass 2.4.2, pentosyltransferases) that transfers d-ribose 5-phosphate from 5-phospho-alpha-d-ribosyl pyrophosphate to a purine, pyrimidine, or pyridine acceptor, forming a 5'-nucleotide and inorganic pyrophosphate, or d-ribose from d-ribosyl phosphate to a base, forming a nucleoside, or similar pentose transfers; important in nucleotide biosynthesis. Specific phosphoribosyltransferases are preceded by the name of the acceptor base, e.g., uracil phosphoribosyltransferase (i.e., uracil + PRPP &dblarr; UMP + pyrophosphate).

(05 Mar 2000)