of Nucleotide Phosphate Sugars from Ribonucleic Acid Using Nuclease Pr,

This paper (1) describes the enzymatic syntheses of a mixture of aden-osine, guanosine, cytidine, and uridine triphosphates (ATP, CTP, CTP, and UTP)from ribonucleic acid (RNA). RNA was hydrolyzedby nuclease Pr to a mixture of 5'-nucleoside monophosphates. This mix-ture was converted to the nucleoside triphosphates using a mixture of nucleoside monophosphate kinases and acetate kinase, with acetyl phosphate as the ul t imate phosphoryl donor. The nucleoside mono-phosphokinases were extracted from brewer's veast in a four-step procedure. The specific activity of the yeast enzyme preparation after gel permeation chromatography was sufficiently high that the yeast kinases could be immobilized in volumes that were practical for labo-ratory scale syntheses. Conversions from NMP to NTP in a mixture containing 0.34 mol of total nucleoside phosphates were: ATP, 90o/o