STRUCTURAL and physical chemical investigations of transfer RNA, whether fractionated or not, in general require that the material be reasonably pure and essentially free from contaminant RNAs of different kinds. Most of the methods at present used for preparation of sRNA from the cell supernatant involve only removal of the proteins, and as Brown has pointed out in a recent review1, the presence of contaminants in the form of other relatively low molecular weight RNA without transfer function is not to be ruled out. Nor has any method been available for the detection of such impurities, although an apparent sedimentation heterogeneity in a number of preparations has been noted2,3. It therefore appeared desirable to evolve techniques both for observing the purity of sRNA preparations, and of purifying them on a preparative scale if necessary.
Brown, G. L., Progress in Nucleic Acids, 2, 259 (Academic Press, 1963).
Klee, C. B., and Staehelin, M., Biochim. Biophys. Acta, 61, 668 (1962).
Luborsky, S. W., and Cantoni, G. L., ibid., 61, 481 (1962).
Ornstein, L., Disc Electrophoresis, Part 1, Theory (Distillation Products Industries, preprint, 1961).
Davis, B. J., Disc Electrophoresis, Part 2, Material and Methods (Distillation Products Industries, preprint, 1961).
Holley, R. W., Biochem. Biophys. Res. Comm., 10, 186 (1963).
Ohtaka, Y., Uchida, K., and Sakai, T., J. Biochem. (Tokyo), 54, 322 (1963).
Rosset, R., Monier, R., and Julien, J., Bull. Soc. Chim. Biol., 46, 87 (1964).
Schleich, T., and Goldstein, J., Proc. U.S. Nat. Acad. Sci., 52, 744 (1964).
Richards, E. G., Coll, J. A., and Gratzer, W. B. (in preparation).