Multiple sequence alignment of bacterial IF-1, eukaryotic eIF-1A, and their archaeal homologs (aIF-1A). Positions in which sequence conservation is >50% identity are highlighted in black. The last line is a consensus of the six S1 motifs found in E. coli ribosomal protein S1: highlighted uppercase type denotes those residues that are also highly conserved in the IF-1/eIF-1A/aIF-1A family, whereas highlighted lowercase type denotes the residues for which a related amino acid occurs in the family. (Dots denote nonconserved positions in the S1 consensus, and dashes denote gaps/insertions of more than one residue.) The horizontal arrows display the positions of the β-strands according to the three-dimensional structure (33). Protein names (and accession number—when different) are as follows: IF1_ECOLI, E. coli IF-1; IF1-SYNEC, Synechocystis sp. IF-1 (EMBL:D90905_47); IF1_BACSU, Bacillus subtilis IF-1; IF1-DEIRA, unpublished ORF from Deinococcus radiodurans; IF1A_METJA, Methanococcus jannaschii aIF-1A; IF1A-METTH, Methanobacterium thermoautotrophicum unpublished ORF; IF1A-ARCFU, Archaeoglobus fulgidus unpublished ORF; YRP2_THEAC, Thermoplasma acidophilum hypothetical protein; IF1A_WHEAT, Triticum aestivum eIF-1A; IF1A_HUMAN, human eIF-1A; IF1A_RABIT, Oryctolagus cuniculus eIF-1A; IF1A_YEAST, Saccharomyces cerevisiae eIF-1A.

Multiple sequence alignment of the eukaryotic translation initiation eIF-5A protein family with their archaeal homologs and the bacterial translation elongation EF-P family. The minimum domain of eukaryotic IF-5A needed for hypusine modification (51) is boxed; the asterisk denotes the lysine residue that is posttranslationally modified to hypusine. Protein names (and accession number—when different) are as follows: IF5A_METJA, M. jannaschii aIF-5A; IF5A-METTH, M. thermoautotrophicum unpublished ORF; IF5A-ARCFU, A. fulgidus unpublished ORF; IF5A_SULAC, Sulfolobus acidocaldarius aIF-5A; IF5A_HUMAN, human eIF-5A; IF5A_DICDI, Dictyostelium discoideum eIF-5A; IF51_YEAST, S. cerevisiae eIF-5A; IF52_CAEEL, Caenorhabditis elegans eIF-5A; EFP_BACSU, B. subtilis EF-P; EFP_SYNY3, Synechocystis sp. EF-P; EFP_ECOLI, E. coli EF-P; EFP_HELPY, Helicobacter pylori EF-P.

Multiple sequence alignment of the eukaryotic SUI1/eIF-1 protein family with their archaeal and bacterial homologs. Protein names (and accession number—when different) are as follows: YCIH_ECOLI, E. coli hypothetical protein; YCIH_SALTY, Salmonella typhimurium hypothetical protein; YCIH_HAEIN, Haemophilus influenzae hypothetical protein; YCIH-SYNEC, Synechocystis sp. hypothetical protein (European Molecular Biology Laboratory accession no. D64003_48); SUI1-METJA, M. jannaschii hypothetical ORF MJ0463 (Protein Information Resource accession no. G64357); YRP1_METVA, Methanococcus vannielii hypothetical protein; SUI1-METTH, M. thermoautotrophicum unpublished ORF; SUI1-ARCFU, A. fulgidus unpublished ORF; SUI1_HUMAN, human SUI1; SUI1_ANOGA, Anopheles gambiae SUI1; SUI1_YEAST, Saccharomyces cerevisiae SUI1; SUI1_ARATH, Arabidopsis thaliana SUI1.