Abstract
An enzyme which hydrolyzes RNA and which has similar properties to those of ribonuclease T1 was found to be present in the grown culture medium of Streptomyces albogriceolus and it was partially purified. The enzyme purified was heat-stable and did not require metal ions to show its activity. It cleaved RNA at guanylate linkage to produce 2', 3'-cyclic guanylic acid and oligonucleotides having guanylic acid at the terminal.
The author wishes to thank Dr. E. Ohmura and Dr. Y. Sugino for their helpful and fruitful dis-cussion and to Mr. I. Suhara, Mr. H. Tanaka and Mr. K. Ito for their cooperation and technical as-sistance.
