Adenylyl-(5', 2') -adenosine 5'-Phosphate ((2'-5') pA-A) in Crude Crystals of 5'-Adenylic Acid Isolated from Nuclease P₁ (Penicillium Nuclease) Digest of Technical Grade Yeast RNA

Abstract

Adenylyl (5', 2') -adenosine 5'-phosphate ((2'-5') pA-A) was detected in crude crystals of 5'-AMP prepared from Penicillium nuclease (nuclease P₁) digest of a technical grade yeast RNA. While (3'-5') A-A was split by nuclease P₁, spleen phosphodiesterase, snake venom phosphodiesterase or alkali, (2'-5') A-A was not split by a usual level of nuclease P₁ or spleen phosphodiesterase. Nuclease P₁ digests of 12 preparations of technical grade yeast RNA tested were confirmed to contain (2'-5') pA-A. Its content was about 1 to 2% of the AMP component of each RNA preparation. As poly (A) was degraded completely by the Penicillium enzyme into 5'-AMP without formation of any appreciable amount of (2'-5') pA-A, the technical grade RNA is supposed to contain 2'-5' phosphodiester linkages in addition to 3'-5' major linkages.