we studied the ability of these cells to synthesize pyrimidine nucleosides by ribo- and deoxyribosyl transfer between pyrimidine bases or nucleosides and the purine nucleosides inosine and deoxyinosine as donors of ribose 1-phosphate and deoxyribose 1-phosphate , respectively : these reactions involve the activities of purine-nucleoside phosphorylase , and of the two pyrimidine-nucleoside phosphorylases ( uridine phosphorylase and thymidine phosphorylase ) .
C0072728
pyrimidine-nucleoside
C0042006
uridine phosphorylase