Amicoumacin A Inhibits Translation by Stabilizing mRNA Interaction with the Ribosome

• Published in: Molecular cell 2014-11, Vol.56 (4), p.531-540
• Main Authors: Polikanov, Yury S., Osterman, Ilya A., Szal, Teresa, Tashlitsky, Vadim N., Serebryakova, Marina V., Kusochek, Pavel, Bulkley, David, Malanicheva, Irina A., Efimenko, Tatyana A., Efremenkova, Olga V., Konevega, Andrey L., Shaw, Karen J., Bogdanov, Alexey A., Rodnina, Marina V., Dontsova, Olga A., Mankin, Alexander S., Steitz, Thomas A., Sergiev, Petr V.
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; Bacterial Proteins - genetics; Base Sequence; Binding Sites; Coumarins - chemistry; Coumarins - pharmacology; Crystallography, X-Ray; Drug Resistance, Bacterial; Escherichia coli; Microbial Sensitivity Tests; Models, Molecular; Peptide Elongation Factor G - genetics; Protein Biosynthesis - drug effects; Protein Synthesis Inhibitors - chemistry; Protein Synthesis Inhibitors - pharmacology; Ribosome Subunits, Large, Bacterial - chemistry; Ribosome Subunits, Small, Bacterial - chemistry; RNA Stability; RNA, Messenger - metabolism; Staphylococcus aureus - genetics; Thermus thermophilus
• ISSN: 1097-2765; 1097-4164
• DOI: 10.1016/j.molcel.2014.09.020

We demonstrate that the antibiotic amicoumacin A (AMI) is a potent inhibitor of protein synthesis. Resistance mutations in helix 24 of the 16S rRNA mapped the AMI binding site to the small ribosomal subunit. The crystal structure of bacterial ribosome in complex with AMI solved at 2.4 Å resolution revealed that the antibiotic makes contacts with universally conserved nucleotides of 16S rRNA in the E site and the mRNA backbone. Simultaneous interactions of AMI with 16S rRNA and mRNA and the in vivo experimental evidence suggest that it may inhibit the progression of the ribosome along mRNA. Consistent with this proposal, binding of AMI interferes with translocation in vitro. The inhibitory action of AMI can be partly compensated by mutations in the translation elongation factor G. [Display omitted] •The antibiotic amicoumacin A is a potent inhibitor of protein synthesis•Amicoumacin A binds to the ribosome and interacts with 16S rRNA and mRNA•By stabilizing mRNA-ribosome interaction, the antibiotic inhibits translocation Polikanov et al. show that the antibiotic amicoumacin-A (AMI) potently inhibits protein synthesis by interacting simultaneously with 16S rRNA and mRNA to block translocation. Mutations in 16S rRNA or elongation factor G can bypass the inhibitory action of AMI.