Description

IPR000795 is a Translational (tr)-type GTP-binding domain.

<p>Translational GTPases (trGTPases) are a family of proteins in which GTPase activity is stimulated by the large ribosomal subunit. This family includes translation initiation, elongation, and release factors and contains four subfamilies that are widespread, if not ubiquitous, in all three superkingdoms [[cite:PUB00013952]]. The trGTPase family members include bacteria elongation factors, EFTu, EFG, and the initiation factor, IF2, and their archaeal homologues, the EF1, EF2, aeIF5b and aeIF2. They all contain two homologous N-terminal domains: a GTPase or G-domain, followed by an OB-domain. These translational proteins' G-domains are both structurally and functionally related to a larger family of GTPase G proteins [[cite:PUB00013952]]. This entry represents the G-domain of the trGTPases.</p> <p>The basic topology of the tr-type G domain consists of a six-stranded central β-sheet surrounded by five α-helices. Helices α2, α3 and α4 are on one side of the sheet, whereas α1 and α5 are on the other [[cite:PUB00038060]]. GTP is bound by the CTF-type G domain in a way common for G domains involving five conserved sequence motifs termed G1-G5. The base is in contact with the NKxD (G4) and SAx (G5) motifs, and the phosphates of the nucleotide are stabilised by main- and side-chain interactions with the P loop GxxxxGKT (G1). The most severe conformational changes are observed for the two switch regions which contain the xT/Sx (G2) and DxxG (G3) motifs that function as sensors for the presence of the gamma-phosphate. A Mg(2+) ion is coordinated by six oxygen ligands with octahedral coordination geometry; two of the ligands are water molecules, two come from the beta- and gamma-phosphates, and two are provided by the side chains of G1 and G2 threonines [[cite:PUB00074802]].</p>

This description is obtained from EB-eye REST.

Associated GO terms

GO predictions are based solely on the InterPro-to-GO mappings published by EMBL-EBI, which are in turn based on the mapping of predicted domains to the InterPro dataset. The InterPro-to-GO mapping was last updated on April 27, 2020, while the GO metadata was last updated on April 27, 2020.

Associated Lotus transcripts 125