Characterization of mouse UDP-glucose pyrophosphatase, a Nudix hydrolase encoded by the Nudt14 gene.

ABSTRACT: Recombinant mouse UDP-glucose pyrophosphatase (UGPPase), encoded by the Nudt14 gene, was produced in Escherichia coli and purified close to homogeneity. The enzyme catalyzed the conversion of [beta-(32)P]UDP-glucose to [(32)P]glucose-1-P and UMP, confirming that it hydrolyzed the pyrophosphate of the nucleoside diphosphate sugar to generate glucose-1-P and UMP. The enzyme was also active toward ADP-ribose. Activity is dependent on the presence of Mg(2+) and was greatest at alkaline pH above 8. Kinetic analysis indicated a K(m) of approximately 4mM for UDP-glucose and approximately 0.3mM for ADP-ribose. Based on V(max)/K(m) values, the enzyme was approximately 20-fold more active toward ADP-ribose. UGPPase behaves as a dimer in solution and can be cross-linked to generate a species of M(r)

SUBMITTER: Heyen CA 

PROVIDER: S-EPMC2798163 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature