4w2e
Crystal structure of Elongation Factor 4 (EF4/LepA) bound to the Thermus thermophilus 70S ribosomeCrystal structure of Elongation Factor 4 (EF4/LepA) bound to the Thermus thermophilus 70S ribosome
Structural highlights
FunctionRL2_THET8 One of the primary rRNA binding proteins. Required for association of the 30S and 50S subunits to form the 70S ribosome, for tRNA binding and peptide bond formation. It has been suggested to have peptidyltransferase activity; this is somewhat controversial (By similarity). Makes several contacts with the 16S rRNA (forming bridge B7b) in the 70S ribosome.[HAMAP-Rule:MF_01320_B] Publication Abstract from PubMedElongation factor 4 (EF4/LepA) is a highly conserved guanosine triphosphatase translation factor. It was shown to promote back-translocation of tRNAs on posttranslocational ribosome complexes and to compete with elongation factor G for interaction with pretranslocational ribosomes, inhibiting the elongation phase of protein synthesis. Here, we report a crystal structure of EF4-guanosine diphosphate bound to the Thermus thermophilus ribosome with a P-site tRNA at 2.9 angstroms resolution. The C-terminal domain of EF4 reaches into the peptidyl transferase center and interacts with the acceptor stem of the peptidyl-tRNA in the P site. The ribosome is in an unusual state of ratcheting with the 30S subunit rotated clockwise relative to the 50S subunit, resulting in a remodeled decoding center. The structure is consistent with EF4 functioning either as a back-translocase or a ribosome sequester. Ribosome structure. Crystal structure of elongation factor 4 bound to a clockwise ratcheted ribosome.,Gagnon MG, Lin J, Bulkley D, Steitz TA Science. 2014 Aug 8;345(6197):684-7. doi: 10.1126/science.1253525. PMID:25104389[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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