STUDIES ON FORMATION OF TRANSFER RIBONUCLEIC ACID-RIBOSOME COMPLEXES .X. PHENYLALANYL-OLIGONUCLEOTIDE BINDING TO RIBOSOMES AND MECHANISM OF CHLORAMPHENICOL ACTION

The overall peptidyl transfer reaction can be subdivided into two distinct steps: a) binding of the aminoacyl-end of charged tRNA to ribosomes and b) the transfer of the nascent peptide from peptidyl-tRNA to aminoacyl-tRNA, the peptidyl transfer step. An assay is described which measures the binding of a phenylalanyl-oligonucleotide to ribosomes, a process which is considered to represent (a) in the absence of peptide bond formation (b). The binding of phenylalanyl-oligonucleotide to ribosomes requires Mg++ and K+; it is stimulated by tRNA non-specifically. Chloramphenicol inhibits the binding of phenylalanyl-oligonucleotide to ribosomes at concentrations at which the antibiotic inhibits bacterial protein synthesis. The results are consistent with the hypothesis that chloramphenicol inhibits protein synthesis through interference with the binding of the aminoacyl-end of charged tRNA to ribosomes. © 1969.