EMD-42563

Single-particle
3.3 Å
EMD-42563 Deposition: 31/10/2023
Map released: 28/02/2024
Last modified: 08/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-42563

Focus refined map of the head domain of the 30S subunit of Listeria innocua ribosome in complex with HflXr, HPF, and E-site tRNA (structure II-B)

EMD-42563

Single-particle
3.3 Å
EMD-42563 Deposition: 31/10/2023
Map released: 28/02/2024
Last modified: 08/05/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Listeria innocua
Sample: Listeria innocua 70S ribosome in complex with HPF, HflXr and E-site tRNA

Deposition Authors: Seely SM , Basu RS , Gagnon MG
Mechanistic insights into the alternative ribosome recycling by HflXr.
Seely SM , Basu RS , Gagnon MG
(2024) Nucleic Acids Res , 52 , 4053 - 4066
PUBMED: 38407413
DOI: doi:10.1093/nar/gkae128
ISSN: 1362-4962
ASTM: NARHAD
Abstract:
During stress conditions such as heat shock and antibiotic exposure, ribosomes stall on messenger RNAs, leading to inhibition of protein synthesis. To remobilize ribosomes, bacteria use rescue factors such as HflXr, a homolog of the conserved housekeeping GTPase HflX that catalyzes the dissociation of translationally inactive ribosomes into individual subunits. Here we use time-resolved cryo-electron microscopy to elucidate the mechanism of ribosome recycling by Listeria monocytogenes HflXr. Within the 70S ribosome, HflXr displaces helix H69 of the 50S subunit and induces long-range movements of the platform domain of the 30S subunit, disrupting inter-subunit bridges B2b, B2c, B4, B7a and B7b. Our findings unveil a unique ribosome recycling strategy by HflXr which is distinct from that mediated by RRF and EF-G. The resemblance between HflXr and housekeeping HflX suggests that the alternative ribosome recycling mechanism reported here is universal in the prokaryotic kingdom.