The purification and properties of a ribonuclease of the roe of the fish Cyprinus carpio L.

Abstract 1. 1. An acid RNase was purified 620-fold from the roe of the fish Cyprinus carpio L. The recovery was 12.4% and the enzyme appeared to be homogenous as judged by the SDS-Polyacrylamide Gel Electrophoresis (SDS-PAGE). 2. 2. The enzyme displays maximum activity at pH 5.50, I = 50 mM and the mol. wt is 22,000. 3. 3. The purified enzyme shows two molecular forms ( p I 1 = 4.04, p I 2 = 4.75) as revealed by the isoelectric focusing technique. 4. 4. The enzyme hydrolyses both Poly(A) and Poly(U) showing a stronger preference for Poly(U), Neither Poly(G) nor Poly(C) was hydrolysed.