Antibiotic effects on the photoinduced affinity labeling of Escherichia coli ribosomes by puromycin

Abstract

The effect of ribosomal antibiotics on the photoinduced affinity labeling of E. coli ribosomes by puromycin was studied. Although blasticidin S, sparsomycin, lincomycin and erythromycin were essentially without effect, major changes were seen on addition of either chloramphenicol or tetracycline. The products of photoincorporation were characterized by 1- and 2-dimensional gel electrophoresis and by specific immunoprecipitation with antibodies to ribosomal proteins. In the presence of chloramphenicol, protein S14 became the major labeled protein. In the presence of tetracycline, L23 remained the major labeled protein, but the yield of labeled ribosomes was enormously increased and the labeling was more specific for L23. The known modes of action of these antibiotics and the photoreactivity of tetracycline were discussed.