THE ISOLATION OF YEAST RIBOSOMES ASSOCIATED WITH TRIOSE PHOSPHATE DEHYDROGENASE

Abstract

The enzyme triose phosphate dehydrogenase was closely associated with yeast ribosomes and it was only partially removed by repeated homogenization in buffer and centrifugation. Antiserum to the crystalline yeast enzyme resulted in precipitation of a maximum of 8% of the total ribosomal material with enrichment of enzyme activity per mg of RNA. Nonspecific precipitation resulted in an additional 0.6-1.9%. A nonspecific immunological reaction with egg albumin and its anti-serum precipitated 1.7% of the ribosomal population with no enrichment for triose phosphate dehydrogenase. This immunological isolation procedure therefore provides a method for concentrating ribosomal-RNA, associated with a specific enzyme. Although alcohol dehydrogenase activity was demonstrated on yeast ribosomes, the amount of enzyme was so small that antiserum to the enzyme did not precipitate ribosomal material in excess of the controls.