UDPglucuronic acid pyrophosphatase assay with the aid of alkaline phosphatase.

Abstract

A simple and sensitive method has been described for the determination of UDPglucuronic acid pyrophosphatase activity. Pyrophosphatase-free alkaline phosphatase preparation is added to the reaction mixture in order to hydrolyze the phosphate esters (UMP and alpha-D-glucuronic acid 1-phosphate) produced by pyrophosphatase. The inorganic phosphate liberated is measured by a modification of Fiske and SubbaRow's method. The phosphatase coupled method is time saving, easy to perform and accurate. It can also be used for pyrophosphatase assays with other nucleotide substrates like UDPglucose, UDP-N-acetylglucosamine, NAD+, NADH, NADP+ and NADPH.