A glucuronide-decomposing enzyme from rumen micro-organisms. 2. Purification and kinetics

Abstract

A partial purification of the glucuronide-decomposing enzyme associated with the medium-sized microorganisms in the sheep rumen is described. This was achieved by aqueous extraction of an acetone-treated powder and acid precipitation of inactive material, followed by repeated fractional precipitation with ammonium sulfate. The fractionation limits were controlled by use of the specific-property solubility test of Falconer and Taylor (1946). The over-all purification (in terms of enzyme activity/mg N) which was achieved, commencing with strained rumen liquor, was approximately 400-fold. The single pH optimum of enzyme activity varied slightly with the state of purity of the preparation between the limits 6.1-6.6 and was the same for phenyl and phenolphthalein glucuronides. The effect of varying substrate concentration was studied and certain anomalies are discussed.