Susceptibility of ribosomes of the tetracycline-producing strain of Streptomyces aureofaciens to tetracyclines.

Ribosomes from cells of Streptomyces aureofaciens producing tetracycline antibiotics (Tc-ribosomes) differ in electrophoretic mobility of ribosomal proteins S2, S10 and L19 from those of the same strain, where the production of tetracyclines was suppressed by changed cultivation conditions (C-ribosomes). Purified tight vacant couples C- and Tc-ribosomes are equally active in the translation of poly(U). Both types of S. aureofaciens ribosomes are more sensitive to tetracycline and chlortetracycline than ribosomes of Escherichia coli in the Phe-tRNA binding and the translation of poly(U).