Purification and Properties of Uridinediphosphate Glucose Pyrophosphorylase from Escherichia coli K 12*

Abstract

Uridinediphosphate glucose pyrophosphorylase of E. coli K 12 was purified 280 fold. Some of its properties were studied. The Km values for uridinediphosphate glucose, pyrophosphate, glucose-1-phosphate and uridinetriphosphate were 1.3 x 10-4 [image], 1.3 x 10-4 [image], 4.8 x 10-5 [image] and 2.9 x 10-5 [image], respectively. It had a broad pH optimum between 7.5 and 9.0. The equilibrium constant [image] was 5.0. This result indicates that the reaction is favorable for the degradation of uridinediphosphate glucose. The enzyme requires Mg ion for its activity and is specific for uridinediphosphate glucose.