id ase ▁( a ▁form ▁of ▁x anth ine ▁ox id ored uct ase ) ▁catal y zes ▁the ▁ox id ation ▁of ▁x anth ine ▁to ▁u ric ▁acid ▁ ▁A den ine ▁ ▁A ▁nuc lease ▁fre es ▁the ▁nucle ot ide ▁ ▁A ▁nucle ot id ase ▁creates ▁ad en os ine , ▁then ▁ad en os ine ▁de amin ase ▁creates ▁in os ine ▁ ▁Alternatively , ▁A MP ▁de amin ase ▁creates ▁in os in ic ▁acid , ▁then ▁a ▁nucle ot id ase ▁creates ▁in os ine ▁ ▁Pur ine ▁nucle os ide ▁ph osph ory l ase ▁acts ▁upon ▁in os ine ▁to ▁create ▁hy po x anth ine ▁ ▁X anth ine ▁ox id ase ▁catal y zes ▁the ▁bi otr ans formation ▁of ▁hy po x anth ine ▁to ▁x anth ine ▁ ▁X anth ine ▁ox id ase ▁acts ▁upon ▁x anth ine ▁to ▁create ▁u ric ▁acid ▁ ▁Reg ulations ▁of ▁pur ine ▁nucle ot ide ▁b ios yn thesis ▁The ▁formation ▁of ▁ 5 '- ph osph or ib os yal am ine ▁from ▁gl ut am ine ▁and ▁PR PP ▁catal ys ed ▁by ▁PR PP ▁am ino ▁transfer ase ▁is ▁the ▁reg ulation ▁point ▁for ▁pur ine ▁synth esis . ▁The ▁en zym e ▁is ▁an ▁al loster ic ▁en zym e , ▁so ▁it ▁can ▁be ▁converted ▁from ▁I MP , ▁G MP ▁and ▁A MP ▁in ▁high ▁concentration ▁bind s ▁the ▁en zym e ▁to ▁ex ert