1OND: The Crystal Structure Of The 50s Large Ribosomal Subunit From Deinococcus Radiodurans Complexed With Troleandomycin Macrolide Antibiotic

Nascent proteins emerge out of ribosomes through an exit tunnel, which was assumed to be a firmly built passive path. Recent biochemical results, however, indicate that the tunnel plays an active role in sequence-specific gating of nascent chains and in responding to cellular signals. Consistently, modulation of the tunnel shape, caused by the binding of the semi-synthetic macrolide troleandomycin to the large ribosomal subunit from Deinococcus radiodurans, was revealed crystallographically. The results provide insights into the tunnel dynamics at high resolution. Here we show that, in addition to the typical steric blockage of the ribosomal tunnel by macrolides, troleandomycin induces a conformational rearrangement in a wall constituent, protein L22, flipping the tip of its highly conserved beta-hairpin across the tunnel. On the basis of mutations that alleviate elongation arrest, the tunnel motion could be correlated with sequence discrimination and gating, suggesting that specific arrest motifs within nascent chain sequences may induce a similar gating mechanism.
PDB ID: 1ONDDownload
MMDB ID: 22801
PDB Deposition Date: 2003/2/27
Updated in MMDB: 2012/10
Experimental Method:
x-ray diffraction
Resolution: 3.4  Å
Source Organism:
Similar Structures:
Biological Unit for 1OND: trimeric; determined by author
Molecular Components in 1OND
Label Count Molecule
Proteins (2 molecules)
50S Ribosomal Protein L22(Gene symbol: rplV)
Molecule annotation
50S Ribosomal Protein L32(Gene symbol: rpmF)
Molecule annotation
Nucleotide(1 molecule)
23S Ribosomal RNA
Molecule annotation
Chemical (1 molecule)
* Click molecule labels to explore molecular sequence information.

Citing MMDB