Human hypoxanthine-guanine phosphoribosyltransferase. Steady state kinetics of the forward and reverse reactions.
A steady state kinetic study of the hypoxanthine-guanine phosphoribosyltransferase-catalyzed reaction in the forward and the reverse directions was carried out. The results obtained favor a sequential mechanism where the monomagnesium complexes of IMP and PPi bind to the enzyme in a rapid equilibrium random fashion while products must dissociate from the enzyme in ordered sequence, first the purine base and then the magnesium complex(es) of P-Rib-PP.
D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000097:blood / Q000378:metabolism*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008433:Mathematics
D007041:Hypoxanthine Phosphoribosyltransferase; D008274:Magnesium