A CHROMATOGRAPHIC INVESTIGATION OF PANCREATIC RIBONUCLEASE

Abstract

Solutes of high molecular weight, such as proteins, present special problems not encountered in the chromatography of simpler organic molecules. Successful elution analysis requires conditions under which proteins will be retarded on a column and will move as discrete zones, giving rise to relatively sharp and symmetrical peaks on an elution curve (1). One of the first proteins to be effectively chromatographed in this manner has been the relatively stable enzyme ribonuclease. Martin and Porter (2) successfully chromatographed ribonuclease on columns prepared by adding aqueous ammonium sulfate saturated with ethylene glycol monoethyl ether (Cellosolve) to kieselguhr, with the aqueous phase as the eluting solvent. In experiments reported from this laboratory (3), with columns of the carboxylic acid ion exchange resin Amberlite IRC-50, it has been found that ribonuclease can be chromatographed under conditions similar in many ways to those employed for the separation of amino acids and simple peptides on ion exchange columns. The present communication describes t’he application of columns of IRC-50.to studies of the homogeneity of various preparations of ribonuclease and to the chromatographic examination of crude pancreatic extracts for their ribonuclease content.