1ZO1

IF2, IF1, and tRNA fitted to cryo-EM data OF E. COLI 70S initiation complex

Summary for 1ZO1

• Entry DOI: 10.2210/pdb1zo1/pdb
• Related: 1Z03
• EMDB information: 1248 1249
• Descriptor: P/I-site tRNA, translation initiation factor 2, translation Initiation Factor 1 (3 entities in total)
• Functional Keywords: e. coli, ribosome, initiation of protein synthesis, initiation factor, cryo-eletron microscopy, translation-rna complex, translation/rna
• Biological source: Escherichia coli; More
• Total number of polymer chains: 3
• Total formula weight: 86844.86

Authors

Allen, G.S.,Zavialov, A.,Gursky, R.,Ehrenberg, M.,Frank, J. (deposition date: 2005-05-12, release date: 2005-06-14, Last modification date: 2024-02-14)

Primary citation

Allen, G.S.,Zavialov, A.,Gursky, R.,Ehrenberg, M.,Frank, J.
The Cryo-EM Structure of a Translation Initiation Complex from Escherichia coli.
Cell(Cambridge,Mass.), 121:703-712, 2005

PubMed Abstract: The 70S ribosome and its complement of factors required for initiation of translation in E. coli were purified separately and reassembled in vitro with GDPNP, producing a stable initiation complex (IC) stalled after 70S assembly. We have obtained a cryo-EM reconstruction of the IC showing IF2*GDPNP at the intersubunit cleft of the 70S ribosome. IF2*GDPNP contacts the 30S and 50S subunits as well as fMet-tRNA(fMet). IF2 here adopts a conformation radically different from that seen in the recent crystal structure of IF2. The C-terminal domain of IF2 binds to the single-stranded portion of fMet-tRNA(fMet), thereby forcing the tRNA into a novel orientation at the P site. The GTP binding domain of IF2 binds to the GTPase-associated center of the 50S subunit in a manner similar to EF-G and EF-Tu. Additionally, we present evidence for the localization of IF1, IF3, one C-terminal domain of L7/L12, and the N-terminal domain of IF2 in the initiation complex.

PubMed: 15935757
DOI: 10.1016/j.cell.2005.03.023

Experimental method

ELECTRON MICROSCOPY (13.8 Å)