Comparison of the mechanism of action of cyclic 11,12-erythromycin A carbonate and erythromycin A.

Synthesis of polyphenylalanine and polylysine in the E. coli MRE 600 and Q 13 cell-free systems was inhibited by erythromycin A and cyclic 11, 12-erythromycin A carbonate to a similar or identical extent. Both compounds inhibited translation of phage f2 RNA in the E. coli Q13 cell-free system. Neither antibiotic affected binding of initiator tRNA or phage f2 RNA to E. coli ribosomes, and neither inhibited translation of BMV RNA in the wheat-germ cell-free system.