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Visualization of tRNA movements on the Escherichia coli 70S ribosome during the elongation cycle.

ABSTRACT: Three-dimensional cryomaps have been reconstructed for tRNA-ribosome complexes in pre- and posttranslocational states at 17-A resolution. The positions of tRNAs in the A and P sites in the pretranslocational complexes and in the P and E sites in the posttranslocational complexes have been determined. Of these, the P-site tRNA position is the same as seen earlier in the initiation-like fMet-tRNA(f)(Met)-ribosome complex, where it was visualized with high accuracy. Now, the positions of the A- and E-site tRNAs are determined with similar accuracy. The positions of the CCA end of the tRNAs at the A site are different before and after peptide bond formation. The relative positions of anticodons of P- and E-site tRNAs in the posttranslocational state are such that a codon-anticodon interaction at the E site appears feasible.

SUBMITTER: Agrawal RK

PROVIDER: S-EPMC2175196 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature

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Visualization of tRNA movements on the Escherichia coli 70S ribosome during the elongation cycle.

Agrawal R K RK Spahn C M CM Penczek P P Grassucci R A RA Nierhaus K H KH Frank J J

The Journal of cell biology 20000801 3

Three-dimensional cryomaps have been reconstructed for tRNA-ribosome complexes in pre- and posttranslocational states at 17-A resolution. The positions of tRNAs in the A and P sites in the pretranslocational complexes and in the P and E sites in the posttranslocational complexes have been determined. Of these, the P-site tRNA position is the same as seen earlier in the initiation-like fMet-tRNA(f)(Met)-ribosome complex, where it was visualized with high accuracy. Now, the positions of the A- and ...[more]

PMID: 10931859

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