Syntheses of polypeptides corresponding to ribonuclease T 1 and its analog, [59-tyrosine]-ribonuclease T 1

Abstract

Two polypeptides with the sequence of ribonuclease T 1 and its analog, [59-tyrosine]-ribonuclease T 1 were prepared by the solid-phase method. After purification by gel filtration and ion exchange chromatography, the synthetic peptides afforded similar patterns on paper and disc electrophoreses to those of natural enzyme. Further purification of the peptide corresponding to ribonuclease T 1 raised the specific activity to 59% for RNA and 44% for guanosine 2′,3′-cyclic phosphate. In case of [59-tyrosine]-ribonuclease T 1, the activity was raised to 61% and 57%, respectively.