Some qualities and fractionation of a nuclease from cotyledons of germinating Phaseolus vulgaris

During gel filtration and subsequent anion exchange chromatography the nuclease activity from cotyledons of germinating Phaseolus vulgaris L. was eluted as a single peak, containing high RNase and low inherent DNase activities. The RNase activity was unaffected by EDTA and had no particular requirement for mono- or divalent cations, but was substantially inhibited by Mn++ and Zn++. Sodium dodecyl sulphate and the vanadyl ribonucleoside complex were identified as effective inhibitors of the RNase activity. The base preference for homoribonucleic acids was: poly U>poly C>poly A>poly G