Sugar-unspecific Mung Bean Nuclease I

When a crude extract of sprouted mung beans is passed through a column of Sephadex G-100, two peaks containing deoxyribonuclease activity and three peaks containing ribonuclease activity are detected, all at pH 5.0, without an additional activating cation. The name mung bean nuclease I is suggested for the enzyme that is first eluted. It corresponds to the enzyme previously described by Sung and Laskowski (1). This enzyme is further purified on Sephadex G-100. Additional evidence for lack of specificity toward sugar is presented. The purified enzyme is highly specific for denatured DNA.