InterPro domain: IPR033720

Elongation factors Tu (EF-Tu) are three-domain GTPases with an essential function in the elongation phase of mRNA translation. The GTPase centre of EF-Tu is in the N-terminal domain (domain I), also known as the catalytic or G-domain. The G-domain is composed of about 200 amino acid residues, arranged into a predominantly parallel six-stranded beta-sheet core surrounded by seven a-helices. Non-catalytic domains II and III are beta-barrels of seven and six, respectively, antiparallel beta-strands that share an extended interface. Either non-catalytic domain is composed of about 100 amino acid residues. EF-Tu proteins exist in two principal conformations: in a compact one, EF-Tu*GTP, with tight interfaces between all three domains and a high affinity for aminoacyl-tRNA, and in an open one, EF-Tu*GDP, with essentially no G-domain-domain II interactions and a low affinity for aminoacyl-tRNA. EF-Tu has approximately a 100-fold higher affinity for GDP than for GTP [ 1 , 2 , 3 , 4 ].

This entry represents domain II.

1. Elongation factors on the ribosome. Curr. Opin. Struct. Biol. 15, 349-54
2. How can elongation factors EF-G and EF-Tu discriminate the functional state of the ribosome using the same binding site? FEBS Lett. 579, 5439-42
3. Mechanisms of EF-Tu, a pioneer GTPase. Prog. Nucleic Acid Res. Mol. Biol. 71, 513-51
4. Ribosome structure and the mechanism of translation. Cell 108, 557-72