TERMINAL-SEQUENCE STUDIES OF HIGH-MOLECULAR-WEIGHT RIBONUCLEIC. THE REACTION OF PERIODATE-OXIDIZED RIBONUCLEOSIDES, 5′-RIBONUCLEOTIDES AND RIBONUCLEIC ACID WITH ISONIAZID

Abstract

The reaction products of isoniazid with periodate-oxldlzed ribonucleosldes and 5[image]-ribonucleotides have been characterized as the monohydrazones. The stability, chromatographic and electrophoretic properties of the hydrazones are described. 3H-labelled isoniazid was shown to react with the 5[image]-linked terminal adenosine and cytidine groups of periodate-oxidized Escherichia coli transfer RNA. One mole of isoniazid reacts with 27 x 103g. of the transfer RNA. One mole of 3H-labelled isoniazid reacts with approx. 106g. of rabbit-retlculocyte ribo-somal RNA. After fractionation of the RNA into its two components and treating the fractionated material with pancreatic ribonuclease and ribonuclease T1 evidence is presented for the existence of two 5[image]-linked terminal sequences in the 30s fraction and only one sequence in the 17s fraction. The application of this method to determining terminal sequences of high-molecular-weight RNA is discussed.