The Ribonuclease-Activity of Barley

Abstract

1. Harley-ribonuclease has been partially purified from dried rootlets, obtained as a by product from the malt industry. 2. By chromatography on a hydroxyapatite column the enzyme preparation can be completely freed from the non-specific phosphodiesterase and to a large extend from the phosphomonoesterase. 3. Soule general characteristics of barley-ribonuclease are described. The activity is optimal at pH 6.1. Cu⁺⁺ and Zn⁺⁺ are potent inhibitors. Free sulfhydryl-groups are not essential for activity. Neutral solutions can be stored for years, and are relatively thermostable. An enzyme solution at pH 1 resists 1 min. heating at 100° C.