抄録
The action pattern of crystalline ribonuclease of Rhitopus niveus was investigated. The enzyme degraded homopolynucleotides in the following order: poly-U>poly-C>poly-A>poly-I_??_poly-G. The enzyme also attacked yeast RNA and produced G-, A-, U- and C-cyclic p in the decreasing order. A significant weakness of activity of hydrolyzing mononucleoside 2', 3'-cyclic phosphates was found as a characteristic of the enzyme and thus under certain conditions, the cyclic phosphates were accumulated almost quantitatively in the digests of yeast RNA and homopolynucleotides with the enzyme.
