Isolation and characterization of fourteen ribosomal proteins from small subunits of yeast.

A method for preparation of a large amount of ribosomal subunits from Saccharomyces cerevisiae by a Ti-15 zonal rotor is described. The proteins of the small subunits (ca. 50 000 A260 units) were separated into 22 fractions by chromatography on carboxymethylcellulose columns. Fourteen proteins were then purified from the ten chromatographic fractions by filtration through Sephadex G-100 or Sephacryl S--200. The isolated proteins are YP 6, YP 7, YP 9, YP 12, YP 14', YP 14'', YP 28, YP 38, YP 45, YP 50, YP 52, YP 58, YP 63, and YP 70. The molecular weight and amino acid compositions of these proteins are presented.