A ratchet-like inter-subunit reorganization of the ribosome during translocation

@article{Frank2000ARI,
  title={A ratchet-like inter-subunit reorganization of the ribosome during translocation},
  author={Joachim Frank and Rajendra K. Agrawal},
  journal={Nature},
  year={2000},
  volume={406},
  pages={318-322}
}
The ribosome is a macromolecular assembly that is responsible for protein biosynthesis following genetic instructions in all organisms. It is composed of two unequal subunits: the smaller subunit binds messenger RNA and the anticodon end of transfer RNAs, and helps to decode the mRNA; and the larger subunit interacts with the amino-acid-carrying end of tRNAs and catalyses the formation of the peptide bonds. After peptide-bond formation, elongation factor G (EF-G) binds to the ribosome… 

Molecular mechanics of 30S subunit head rotation

Comparative structure analysis across 55 ribosome structures shows that 30S head movement results from flexing at two hinge points lying within conserved elements of 16S rRNA, which explains the mode of action of spectinomycin, an antibiotic that blocks translocation by binding to hinge 2.

Structure of the ribosome with elongation factor G trapped in the pretranslocation state

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Head swivel on the ribosome facilitates translocation via intra-subunit tRNA hybrid sites

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Ribosomal crystallography: peptide bond formation and its inhibition.

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Elongation Factor G Bound to the Ribosome in an Intermediate State of Translocation

Comparison with the posttranslocational state suggests that interactions between the tRNA and L1 stalk are preserved throughout translocation and that these are probably an essential feature of translocation required for stabilization of the hybrid P/E state.

The Ribosome as an RNA-Based Molecular Machine

The binding of functional ligands, such as aminoacyl-tRNA and an elongation factor with GTP, and the chemical reactions of transpeptidation and GTP hydrolysis play the role of a Maxwell's Demon: they rectify the random fluctuations to produce the unidirectional conveyance process and translation.

Following movement of domain IV of elongation factor G during ribosomal translocation

This work follows the movement of domain IV of EF-G, which is critical for the catalysis of translocation, relative to protein S12 of the small ribosomal subunit using single-molecule FRET and shows that ribosome-boundEF-G adopts distinct conformations corresponding to the pre- and posttranslocation states of the ribosomes.
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