This protein promotes the GTP-dependent binding of aminoacyl-tRNA to the A-site of ribosomes during protein biosynthesis. EF-Tu-GDP binds to the acceptor arm of tmRNA by interacting with its acceptor arm, suggesting that GTP hydrolysis by EF-Tu is essential for tmRNA function. Protects glycyl-tRNA(Gly) from hydrolysis by E.coli D-aminoacyl-tRNA deacylase (dtd) (PubMed:27224426). Monomer (By similarity). Binds to the 70S ribosome, contacts tmRNA during trans-translation (PubMed:12677067). Phosphorylated on a threonine. Belongs to the TRAFAC class translation factor GTPase superfamily. Classic translation factor GTPase family. EF-Tu/EF-1A subfamily.