A simple procedure for partial purification of an RNAase of Entamoeba invadens

The behavior of an RNAase, present in centrifugally clarified homogenates of axenic trophozoites of Entamoeba invadens, on isoelectric focusing (IEF) and agarose-poly(G) chromatography is described. The results led to a simple two-step procedure for partial purification of the RNAase in which fractionation of the homogenate by IEF is followed by agarose-poly(G) chromatography. Recovery of enzyme activity has ranged from 50 to 80% of that present in homogenates, and increases of 80- to 160-fold in the specific activity have been obtained using the procedure. A single zone of activity was observed on analysis of the partially purified RNAase by sucrose gradient IEF and velocity zonal ultracentrifugation.