Type: | Domain | Name: | Translation elongation factor EFG, V domain |
Description: | 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 [, ]. 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.EF2 is folded into five domains, with domains I and II forming the N-terminal block, domains IV and V forming the C-terminal block, and domain III providing the covalently-linked flexible connection between the two []. This entry represents the domain V of EF2 of both prokaryotes and eukaryotes (also known as eEF2). This domain is also found in some tetracycline-resistance proteins. It 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, but these two domains cannot be superimposed []. | Short Name: | EFG_V |