1eft

From Proteopedia

THE CRYSTAL STRUCTURE OF ELONGATION FACTOR EF-TU FROM THERMUS AQUATICUS IN THE GTP CONFORMATION

Overview

BACKGROUND: Elongation factor Tu (EF-Tu) is a GTP-binding protein that is crucial for protein biosynthesis. In the GTP form of the molecule, EF-Tu binds tightly to aminoacyl-tRNA, forming a ternary complex that interacts with the ribosomal acceptor site. During this interaction, GTP is hydrolyzed, and EF-Tu.GDP is ejected. RESULTS: The crystal structure of EF-Tu from Thermus aquaticus, complexed to the GTP analogue GDPNP, has been determined at 2.5 A resolution and compared to the structure of Escherichia coli EF-Tu.GDP. During the transition from the GDP (inactive) to the GTP (active) form, domain 1, containing the GTP-binding site, undergoes internal conformational changes similar to those observed in ras-p21. In addition, a dramatic rearrangement of domains is observed, corresponding to a rotation of 90.8 degrees of domain 1 relative to domains 2 and 3. Residues that are affected in the binding of aminoacyl-tRNA are found in or near the cleft formed by the domain interface. CONCLUSION: GTP binding by EF-Tu leads to dramatic conformational changes which expose the tRNA binding site. It appears that tRNA binding to EF-Tu induces a further conformational change, which may affect the GTPase activity.

About this Structure

1EFT is a Single protein structure of sequence from Thermus aquaticus with and as ligands. The following page contains interesting information on the relation of 1EFT with [Elongation Factors]. Full crystallographic information is available from OCA.

Reference

The crystal structure of elongation factor EF-Tu from Thermus aquaticus in the GTP conformation., Kjeldgaard M, Nissen P, Thirup S, Nyborg J, Structure. 1993 Sep 15;1(1):35-50. PMID:8069622

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