RIBOSOMAL-PROTEINS OF STREPTOMYCES-AUREOFACIENS PRODUCING TETRACYCLINE

Three different 2-dimensional polyacrylamide gel electrophoresis systems were employed for identification of individual ribosomal proteins of S. aureofaciens. Proteins of small subunits were resolved into 21 spots. Larger ribosomal subunits contained 35 proteins. The separated ribosomal proteins from 50 S subunits were transferred on nitrocellulose membranes for immunochemical estimations. Antibodies developed against 50 S proteins of S. aureofaciens and Escherichia coli were used for identification of structural homologies between 50 S proteins of the 2 species. About 1/2 of the 50 S proteins of S. aureofaciens share common immunochemical determinants with corresponding proteins of 50 S subunits of E. coli. Acidic ribosomal protein SL5 of large ribosomal subunits of S. aureofaciens can be assembled to E. coli P0 cores lacking proteins L7/L12. Reconstitution of the P0 cores with SL5 or L7/L12 led to restoration of 78% activity in polyphenylalanine synthesis.