5KPS

Structure of RelA bound to ribosome in absence of A/R tRNA (Structure I)

This is a non-PDB format compatible entry.

Summary for 5KPS

• Entry DOI: 10.2210/pdb5kps/pdb
• Related: 5KPV 5KPW 5KPX
• EMDB information: 8279 8280 8281 8282
• Descriptor: GTP pyrophosphokinase, 50S ribosomal protein L13, 50S ribosomal protein L14, ... (58 entities in total)
• Functional Keywords: ribosome, rela
• Biological source: Escherichia coli (strain K12); More
• Total number of polymer chains: 58
• Total formula weight: 2311715.67

Authors

Loveland, A.B.,Bah, E.,Madireddy, R.,Zhang, Y.,Brilot, A.F.,Grigorieff, N.,Korostelev, A.A. (deposition date: 2016-07-05, release date: 2016-09-28, Last modification date: 2024-11-20)

Primary citation

Loveland, A.B.,Bah, E.,Madireddy, R.,Zhang, Y.,Brilot, A.F.,Grigorieff, N.,Korostelev, A.A.
Ribosome•RelA structures reveal the mechanism of stringent response activation.
Elife, 5:-, 2016

PubMed Abstract: Stringent response is a conserved bacterial stress response underlying virulence and antibiotic resistance. RelA/SpoT-homolog proteins synthesize transcriptional modulators (p)ppGpp, allowing bacteria to adapt to stress. RelA is activated during amino-acid starvation, when cognate deacyl-tRNA binds to the ribosomal A (aminoacyl-tRNA) site. We report four cryo-EM structures of E. coli RelA bound to the 70S ribosome, in the absence and presence of deacyl-tRNA accommodating in the 30S A site. The boomerang-shaped RelA with a wingspan of more than 100 Å wraps around the A/R (30S A-site/RelA-bound) tRNA. The CCA end of the A/R tRNA pins the central TGS domain against the 30S subunit, presenting the (p)ppGpp-synthetase domain near the 30S spur. The ribosome and A/R tRNA are captured in three conformations, revealing hitherto elusive states of tRNA engagement with the ribosomal decoding center. Decoding-center rearrangements are coupled with the step-wise 30S-subunit 'closure', providing insights into the dynamics of high-fidelity tRNA decoding.

PubMed: 27434674
DOI: 10.7554/eLife.17029

Experimental method

ELECTRON MICROSCOPY (3.9 Å)