1pn7 is a 3 chain structure with sequence from Thermotoga maritima and Thermus thermophilus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
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.
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[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Valle M, Zavialov A, Sengupta J, Rawat U, Ehrenberg M, Frank J. Locking and unlocking of ribosomal motions. Cell. 2003 Jul 11;114(1):123-34. PMID:12859903