Studies on transfer ribonucleic acid-ribosome complexes. XXI. Effect of antibiotics on peptidyl-puromycin synthesis by mammalian polyribosomes.

The effect of antibiotics and other agents on-peptide bond synthesis by mammalian polyribosomes was determined by studying peptidyl-puromycin synthesis. Sparsomycin, anisomycin, cycloheximide, gougerotin, blasticidin S, and cryptopleurine inhibited the reaction. Sparsomycin and anisomytin inhibited the peptidyl-puromycin synthesis competitively with respect to puromycin. Arabinose analogs of puromycin as well as many other antibiotics were ineffective as inhibitors of this reaction. In addition, the results demonstrated that antibiotics and other agents influence peptide bond formation on polyribosomes differently than peptide bond synthesis as measured by acetyl-phenylalanyl-puromycin synthesis. It is thus suggested that the former assay is probably more representative of the mode of action of these agents in the intact cell than the latter.