Studies on Two Nucleases and a Ribonuclease from Physarum polycephalum Purification and Mode of Action
1969 Volume 65 Issue 5 Pages 701-708
Details
1969 Volume 65 Issue 5 Pages 701-708
1. Two nucleases hydrolyzing both RNA and denatured DNA (Nucleases Pp-1, and Pp-2) and one ribonuclease (RNase Pp-4) were isolated from Physarum polycephalum in addition to the three RNases (RNases Pp-1, Pp-2, and Pp-3, ) reported in the preceding paper (1).
2. They are thermolabile.
3. The pH optima of nucleases Pp-1 and Pp-2 are pH 4.5, and that of RNase Pp-4 is pH 4.0.
4. Nuclease Pp-1 and nuclease Pp-2 hydrolyze denatured DNA as well as RNA, but not native DNA.
5. Nuclease Pp-1 hydrolyzes RNA forming nucleotides with terminal 3'-phosphate.
6. Nuclease Pp-2, hydrolyzes RNA to produce nucleotides with terminal 5'-phosphate. It has no base specificity.
7. RNase Pp-4 hydrolyzes RNA forming nucleotides bearing 5'-phosphate group with purine preference in regards to 3'-terminal nucleotides.
8. Nuclease Pp-2 and RNase Pp-4 are strongly activated by Zn++
