Nascent peptide-mediated ribosome stalling promoted by antibiotics

Abstract

Ribosomes are macromolecular assemblies that are the sites for protein synthesis or translation in all cells. The key step of protein synthesis on ribosomes is peptidyl transfer in which the growing polypeptide is extended by one amino acid in each cycle of elongation according to the sequence of codons of a messenger RNA (mRNA). The ribosome has a binding site for mRNA and three for transfer RNA (tRNA) molecules. Ribosomes are composed of two subunits, the large and the small subunit, both of which consist of ribosomal RNA (rRNA) molecules and a variable number of ribosomal proteins. Several factor proteins catalyze different steps of protein synthesis by binding transiently to the ribosome. The fidelity of translation of the genetic code is of critical importance for the production of functional proteins and for the viability of the cell. Escherichia coli is the reference organism. Protein synthesis on ribosomes follows a closely related pattern in other organisms. Important differences that are clearly established will be specified.