Purification and Characterization of a β-Glucuronidase Present During Embryogenesis of the Mollusk Pomacea sp.

A β-glucuronidase was purified from Pomacea sp. eggs by ammonium sulfate fractionation, DEAE-BioGel and Heparin-Sepharose chromatographies. This enzyme showed a Mr 180 kDa, with subunits of 90 kDa. The kinetic parameters were: pH 4.0, temperature 60°C, Km 2.7 x 10-6 and Vmax 15.3 μM/h, activator Mg+2, and inhibitor: lactone of D-saccharic acid. β-glucuronidase is an exoglucuronidase involved in glycosaminoglycans metabolism with kinetics parameters similar to those found in mammals.