Abstract
GMP reductase (EC 1.6.6.8) has been purified from human erythrocytes. The steady-state kinetics of the reaction catalyzed by GMP reductase are consistent with a model in which substrates bind the enzyme in an ordered sequence, first GMP and then NADPH. NADP is released from the enzyme-substrate complex by a Theorell-Chance mechanism. Ammonia and IMP are then sequentially liberated in an ordered fashion. Deadend complexes between the enzyme and ammonia have been observed. GTP (10-200 uM) increases the apparent second-order rate constant for GMP binding and thus decreases the inhibition constant of this substrate. Neither Vmax nor Km for NADPH are affected by GTP up to 200 uM.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Spadaro, A., Giacomello, A. & Salerno, C. STEADY-STATE KINETICS OF THE REACTION CATALYZED BY GMP REDUCTASE: 204. Pediatr Res 19, 777 (1985). https://doi.org/10.1203/00006450-198507000-00224
Issue Date:
DOI: https://doi.org/10.1203/00006450-198507000-00224