As a reflection of its crucial role in translation, EF-Tu is one of the most abundant and highly conserved proteins in prokaryotes.

[5] As a family of elongation factors, EF-Tu also includes its eukaryotic and archaeal homolog, the alpha subunit of eEF-1 (EF-1A).

Messenger RNA (mRNA) carries the genetic information that encodes the primary structure of a protein, and contains codons that code for each amino acid.

Then, in a process catalyzed by the prokaryotic elongation factor EF-G (historically known as translocase), the coordinated translocation of the tRNAs and mRNA occurs, with the P-site tRNA moving to the E-site, where it dissociates from the ribosome, and the A-site tRNA moves to take its place in the P-site.

[8] EF-Tu • GTP binds all correctly-charged aa-tRNAs with approximately identical affinity, except those charged with initiation residues and selenocysteine.

Upon GTP hydrolysis, the conformation of EF-Tu changes drastically and dissociates from the aa-tRNA and ribosome complex.

[15][16] A third mechanism is the less well understood function of EF-Tu to crudely check aa-tRNA associations and reject complexes where the amino acid is not bound to the correct tRNA coding for it.

[19] Additionally, EF-Tu has displayed some chaperone-like characteristics, with some experimental evidence suggesting that it promotes the refolding of a number of denatured proteins in vitro.

[27][28] The GTP-binding domain I undergoes a dramatic conformational change upon GTP hydrolysis to GDP, allowing EF-Tu to dissociate from aa-tRNA and leave the ribosome.

[32] The GTP-binding domain is conserved in both EF-1alpha/EF-Tu and also in EF-2/EF-G and thus seems typical for GTP-dependent proteins which bind non-initiator tRNAs to the ribosome.

[38] The second group includes the antibiotics kirromycin and enacyloxin, and prevents the release of EF-Tu from the ribosome after GTP hydrolysis.