... respectively, of that of HPRT. This low activitycould be explained by the fact that PRTFDC1 has a Gly in the position of the proposed catalytic Asp of HPRT. In PRTFDC1, a water molecule at the position of ... andregulators of other enzymes in the human nucleotidemetabolism (Table S1). The library can then be seen toconstitute the specific metabolome of the nucleotidemetabolism, which would be the most ... and0.09%, respectively, of the activity of HPRT, the role of the PRTFDC1 in purine metabolism remainsunclear and it is uncertain whether it has the capacityto compensate for a deficiency or partial...