RAPP-containing arrest peptides induce translational stalling by short circuiting the ribosomal peptidyltransferase activity.

ABSTRACT: Arrest peptides containing RAPP (ArgAlaProPro) motifs have been discovered in both Gram-positive and Gram-negative bacteria, where they are thought to regulate expression of important protein localization machinery components. Here we determine cryo-EM structures of ribosomes stalled on RAPP arrest motifs in both Bacillus subtilis and Escherichia coli. Together with molecular dynamics simulations, our structures reveal that the RAPP motifs allow full accommodation of the A-site tRNA, but prevent the subsequent peptide bond from forming. Our data support a model where the RAP in the P-site interacts and stabilizes a single hydrogen atom on the Pro-tRNA in the A-site, thereby preventing an optimal geometry for the nucleophilic attack required for peptide bond formation to occur. This mechani

SUBMITTER: Morici M 

PROVIDER: S-EPMC10951233 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature