9GGR

Structure of the HrpA-bound E. coli disome, Class II

This is a non-PDB format compatible entry.

Summary for 9GGR

• Entry DOI: 10.2210/pdb9ggr/pdb
• EMDB information: 51318 51340
• Descriptor: 16S ribosomal RNA, Small ribosomal subunit protein uS10, A-site tRNA, ... (63 entities in total)
• Functional Keywords: ribosome, rna helicase
• Biological source: Escherichia coli; More
• Total number of polymer chains: 117
• Total formula weight: 4814219.37

Authors

Esser, H.F.,Berninghausen, O.,Becker, T.,Beckmann, R. (deposition date: 2024-08-14, release date: 2025-02-12, Last modification date: 2025-03-19)

Primary citation

Campbell, A.,Esser, H.F.,Burroughs, A.M.,Berninghausen, O.,Aravind, L.,Becker, T.,Green, R.,Beckmann, R.,Buskirk, A.R.
The RNA helicase HrpA rescues collided ribosomes in E. coli.
Mol.Cell, 85:999-1007.e7, 2025

PubMed Abstract: Although many antibiotics inhibit bacterial ribosomes, the loss of known factors that rescue stalled ribosomes does not lead to robust antibiotic sensitivity in E. coli, suggesting the existence of additional mechanisms. Here, we show that the RNA helicase HrpA rescues stalled ribosomes in E. coli. Acting selectively on ribosomes that have collided, HrpA uses ATP hydrolysis to split stalled ribosomes into subunits. Cryoelectron microscopy (cryo-EM) structures reveal how HrpA simultaneously binds to two collided ribosomes, explaining its selectivity, and how its helicase module engages downstream mRNA such that, by exerting a pulling force on the mRNA, it would destabilize the stalled ribosome. These studies show that ribosome splitting is a conserved mechanism that allows proteobacteria to tolerate ribosome-targeting antibiotics.

PubMed: 39922193
DOI: 10.1016/j.molcel.2025.01.018

Experimental method

ELECTRON MICROSCOPY (3.2 Å)