70S ribosome translocation intermediate containing elongation factor EFG/GDP/fusidic acid, mRNA, and tRNAs trapped in the AP/AP pe/E chimeric hybrid state. This entry contains the 50S ribosomal subunit B. The 30S subunit B can be found in 4QS2. Molecule A in the same asymmetric unit is deposited as 4QS0 (30S) and 4QS1 (50S)
4qs3 is a 36 chain structure with sequence from Thermus thermophilus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Coupled translocation of messenger RNA and transfer RNA (tRNA) through the ribosome, a process catalyzed by elongation factor EF-G, is a crucial step in protein synthesis. The crystal structure of a bacterial translocation complex describes the binding states of two tRNAs trapped in mid-translocation. The deacylated P-site tRNA has moved into a partly translocated pe/E chimeric hybrid state. The anticodon stem-loop of the A-site tRNA is captured in transition toward the 30S P site, while its 3' acceptor end contacts both the A and P loops of the 50S subunit, forming an ap/ap chimeric hybrid state. The structure shows how features of ribosomal RNA rearrange to hand off the A-site tRNA to the P site, revealing an active role for ribosomal RNA in the translocation process.
How the ribosome hands the A-site tRNA to the P site during EF-G-catalyzed translocation.,Zhou J, Lancaster L, Donohue JP, Noller HF Science. 2014 Sep 5;345(6201):1188-91. doi: 10.1126/science.1255030. PMID:25190797[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Zhou J, Lancaster L, Donohue JP, Noller HF. How the ribosome hands the A-site tRNA to the P site during EF-G-catalyzed translocation. Science. 2014 Sep 5;345(6201):1188-91. doi: 10.1126/science.1255030. PMID:25190797 doi:http://dx.doi.org/10.1126/science.1255030
