Preparation of transfer ribonucleic acid with silicic acid

A modification of the nondenaturing procedure of Sueoka and Hardy (1) for the isolation of transfer ribonucleic acid is described. This procedure has been used for the large scale isolation of transfer-RNA from extracts of Escherichia coli and involves a batch treatment with silicic acid, DEAE-cellulose column chromatography, and an optional ethanol precipitation of the product. The final product is homogeneous when run in polyacrylamide gel electrophoresis and highly active with respect to aminoacylation.