Peptidyl puromycin synthesis; effect of several antibiotics which act on 50 S ribosomal subunits.

The effects of several antibiotics which are know to bind with 50 S ribosomal subunits, on the formation of several di- and tri-peptidyl puromycins have been examined. Tylosin and spiramycin inhibited the formation of phenylalanyl-(14)C-phenylalanyl-puromycin, glycyl-(14)C-phenyllalanyl-puromycin, leucyl-(14)C-phenylalanyl-puromycin, N(epsilon)-carbobenzoxylysyl-(14)C-phenylalanyl-puromycin, and valyl-glycyl-(14)C-phenylalanyl-puromycin as well as N-acetyl-(14)C-phenylalanyl-puromycin. Of these compounds, erythromycin and oleandomycin selectively inhibited the formation of phenylalanyl-(14)C-phenylalanyl-puromycin. Although chloramphenicol and lincomycin inhibited the formation of most of these peptidyl puromycins, the formation of phenylalanyl-(14)C-phenylalanyl-puromycin and leucyl-(14)C-phenylalanyl-puromycin was found to be resistant to these antibiotics. So far, no significant effect of siomycin has been observed on pepetidyl puromycin formation in the absence of G factor.