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1pn8
From Proteopedia
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Coordinates of S12, L11 proteins and E-site tRNA from 70S crystal structure separately fitted into the Cryo-EM map of E.coli 70S.EF-G.GDPNP complex. The atomic coordinates originally from the E-site tRNA were fitted in the position of the hybrid P/E-site tRNA.
Overview
During the ribosomal translocation, the binding of elongation factor G (EF-G) to the pretranslocational ribosome leads to a ratchet-like rotation of the 30S subunit relative to the 50S subunit in the direction of the mRNA movement. By means of cryo-electron microscopy we observe that this rotation is accompanied by a 20 A movement of the L1 stalk of the 50S subunit, implying that this region is involved in the translocation of deacylated tRNAs from the P to the E site. These ribosomal motions can occur only when the P-site tRNA is deacylated. Prior to peptidyl-transfer to the A-site tRNA or peptide removal, the presence of the charged P-site tRNA locks the ribosome and prohibits both of these motions.
About this Structure
1PN8 is a Protein complex structure of sequences from Thermotoga maritima and Thermus thermophilus. Full crystallographic information is available from OCA.
Reference
Locking and unlocking of ribosomal motions., Valle M, Zavialov A, Sengupta J, Rawat U, Ehrenberg M, Frank J, Cell. 2003 Jul 11;114(1):123-34. PMID:12859903
Page seeded by OCA on Thu Feb 21 14:30:31 2008
