Oligo- und Polynucleotidtrennungen: IV. Chromatographie von löslicher Ribonucleinsäure und deren Spaltprodukten an Sephadex

Abstract

Chromatography of soluble ribonucleic acid and its cleavage products on Sephadex Chromatographic studies on Sephadex columns with a number of s-RNA preparations, [ 14C]seryl s-RNA, a serine t-RNA fraction, pancreatic and T 1-ribonuclease hydrolysates of RNA, and s-RNA's which were partially degraded by heating, are reported (Figs. 1–7). It was shown that: 1. 1 s-RNA preparations from brewer's yeast, baker's yeast, and Escherichia coli contain varying and sometimes considerable amounts of biologically inactive poly- and oligonucleotides. 2. 2. Seryl and serine t-RNA's are eluted well before many of the other t-RNA's and therefore may differ from them in size and/or secondary structure. 3. 3. The largest oligonucleotides of enzymatic RNA hydrolysates, i.e. octa- to decanucleotides are eluted from columns with Sephadex or polyacrylamide gel immediately after the s-RNA. One of the reasons for this may be aggregation of the oligonucleotides, as was indicated by heating experiments, chromatography in the presence of urea, etc. The isolation of large RNA fragments by standard Sephadex chromatography therefore seems to be difficult.