<p>Translation elongation factors are responsible for two main processes during protein synthesis on the ribosome [<cite idref="PUB00033953"/>, <cite idref="PUB00033952"/>, <cite idref="PUB00033951"/>]. EF1A (or EF-Tu) is responsible for the selection and binding of the cognate aminoacyl-tRNA to the A-site (acceptor site) of the ribosome. EF2 (or EF-G) is responsible for the translocation of the peptidyl-tRNA from the A-site to the P-site (peptidyl-tRNA site) of the ribosome, thereby freeing the A-site for the next aminoacyl-tRNA to bind. Elongation factors are responsible for achieving accuracy of translation and both EF1A and EF2 are remarkably conserved throughout evolution.</p><p>Elongation factor EF2 (EF-G) is a G-protein. It brings about the translocation of peptidyl-tRNA and mRNA through a ratchet-like mechanism: the binding of GTP-EF2 to the ribosome causes a counter-clockwise rotation in the small ribosomal subunit; the hydrolysis of GTP to GDP by EF2 and the subsequent release of EF2 causes a clockwise rotation of the small subunit back to the starting position [<cite idref="PUB00033958"/>, <cite idref="PUB00033959"/>]. This twisting action destabilises tRNA-ribosome interactions, freeing the tRNA to translocate along the ribosome upon GTP-hydrolysis by EF2. EF2 binding also affects the entry and exit channel openings for the mRNA, widening it when bound to enable the mRNA to translocate along the ribosome.</p><p>This entry represents the C-terminal domain found in EF2 (or EF-G) of both prokaryotes and eukaryotes (also known as eEF2), as well as in some tetracycline-resistance proteins. This domain adopts a ferredoxin-like fold consisting of an alpha/beta sandwich with anti-parallel beta-sheets. It resembles the topology of domain III found in these elongation factors, with which it forms the C-terminal block, but these two domains cannot be superimposed [<cite idref="PUB00014828"/>]. This domain is often found associated with (<db_xref db="INTERPRO" dbkey="IPR000795"/>), which contains the signatures for the N terminus of the proteins.</p><p>More information about these proteins can be found at Protein of the Month: Elongation Factors [<cite idref="PUB00033962"/>].</p> Translation elongation factor EFG/EF2, C-terminal