4v71
From Proteopedia
E. coli 70S-fMetVal-tRNAVal-tRNAfMet complex in intermediate pre-translocation state (pre2)
Structural highlights
FunctionRL19_ECOLI This protein is located at the 30S-50S ribosomal subunit interface. In the 70S ribosome (PubMed:12809609) it has been modeled to make two contacts with the 16S rRNA of the 30S subunit forming part of bridges B6 and B8. In the 3.5 A resolved structures (PubMed:16272117) L14 and L19 interact and together make contact with the 16S rRNA. The protein conformation is quite different between the 50S and 70S structures, which may be necessary for translocation.[HAMAP-Rule:MF_00402] Publication Abstract from PubMedDuring protein synthesis, tRNAs move from the ribosome's aminoacyl to peptidyl to exit sites. Here we investigate conformational motions during spontaneous translocation, using molecular dynamics simulations of 13 intermediate-translocation-state models obtained by combining Escherichia coli ribosome crystal structures with cryo-EM data. Resolving fast transitions between states, we find that tRNA motions govern the transition rates within the pre- and post-translocation states. Intersubunit rotations and L1-stalk motion exhibit fast intrinsic submicrosecond dynamics. The L1 stalk drives the tRNA from the peptidyl site and links intersubunit rotation to translocation. Displacement of tRNAs is controlled by 'sliding' and 'stepping' mechanisms involving conserved L16, L5 and L1 residues, thus ensuring binding to the ribosome despite large-scale tRNA movement. Our results complement structural data with a time axis, intrinsic transition rates and molecular forces, revealing correlated functional motions inaccessible by other means. Energy barriers and driving forces in tRNA translocation through the ribosome.,Bock LV, Blau C, Schroder GF, Davydov II, Fischer N, Stark H, Rodnina MV, Vaiana AC, Grubmuller H Nat Struct Mol Biol. 2013 Nov 3. doi: 10.1038/nsmb.2690. PMID:24186064[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. Loading citation details.. Citations No citations found See AlsoReferences
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Categories: Escherichia coli K-12 | Large Structures | Blau C | Bock LV | Davydov I | Fischer N | Grubmuller H | Rodnina MV | Schroder GF | Stark H | Vaiana AC