Domain II of Elongation factor Tu (EF-Tu)-like proteins; Elongation factor Tu consists of three structural domains. Domain II adopts a beta barrel structure and is involved in binding to charged tRNA. Domain II is found in other proteins such as elongation factor G and translation initiation factor IF-2. This group also includes the C2 subdomain of domain IV of IF-2 that has the same fold as domain II of (EF-Tu). Like IF-2 from certain prokaryotes such as Thermus thermophilus, mitochondrial IF-2 lacks domain II, which is thought to be involved in binding of E. coli IF-2 to 30S subunits.

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                 ....*....|....*..
gi 1385097230  6 PTYGRHLEEKDTLYSLI 22
Cdd:cd16266   71 PTVGRHIEEGDILYVDI 87

Domain IV of prokaryotic Initiation Factor 2 and archaeal and eukaryotic Initiation Factor 5; This family represents the domain IV of prokaryotic Initiation Factor 2 (IF2) and its archaeal and eukaryotic homologs IF5B. IF2, the largest initiation factor is an essential GTP binding protein. In E. coli three natural forms of IF2 exist in the cell, IF2alpha, IF2beta1, and IF2beta2. Disruption of the eIF5B gene (FUN12) in yeast causes a severe slow-growth phenotype, associated with a defect in translation. eIF5B has a function analogous to prokaryotic IF2 in mediating the joining of the 60S ribosomal subunit. The eIF5B consists of three N-terminal domains (I, II, II) connected by a long helix to domain IV. Domain I is a G domain, domain II and IV are beta-barrels and domain III has a novel alpha-beta-alpha sandwich fold. The G domain and the beta-barrel domain II display a similar structure and arrangement to the homologous domains in EF1A, eEF1A and aeIF2gamma.

                         10
                 ....*....|....*..
gi 1385097230  6 PTYGRHLEEKDTLYSLI 22
Cdd:cd16266   71 PTVGRHIEEGDILYVDI 87

Domain IV of prokaryotic Initiation Factor 2 and archaeal and eukaryotic Initiation Factor 5; This family represents the domain IV of prokaryotic Initiation Factor 2 (IF2) and its archaeal and eukaryotic homologs IF5B. IF2, the largest initiation factor is an essential GTP binding protein. In E. coli three natural forms of IF2 exist in the cell, IF2alpha, IF2beta1, and IF2beta2. Disruption of the eIF5B gene (FUN12) in yeast causes a severe slow-growth phenotype, associated with a defect in translation. eIF5B has a function analogous to prokaryotic IF2 in mediating the joining of the 60S ribosomal subunit. The eIF5B consists of three N-terminal domains (I, II, II) connected by a long helix to domain IV. Domain I is a G domain, domain II and IV are beta-barrels and domain III has a novel alpha-beta-alpha sandwich fold. The G domain and the beta-barrel domain II display a similar structure and arrangement to the homologous domains in EF1A, eEF1A and aeIF2gamma.

                         10
                 ....*....|....*..
gi 1385097230  6 PTYGRHLEEKDTLYSLI 22
Cdd:cd16266   71 PTVGRHIEEGDILYVDI 87