title: Identification and purification of translation initiation factor 2 (IF2) from Thermus thermophilus.
abstract: Translation initiation factor 2 (IF2) is one of three protein factors required for initiation of protein synthesis in eubacteria. The protein is responsible for binding the initiator RNA to the ribosomal P site. IF2 is a member of the GTP GDP-binding protein superfamily. In the extreme thermophilic bacterium Thermus thermophilus, IF2 was identified as a 66-kDa protein by affinity labeling and immunoblotting. The protein was purified to homogeneity. The specific activity indicates a stoichiometric IF2-mediated binding of formylmethionine-tRNA to 70S ribosomes. The N-terminal amino acid sequences of the intact protein and of two proteolytic fragments of 25 kDa and 40 kDa were determined. Comparison with other bacterial IF2 sequences indicates a similar domain architecture in all bacterial IF2 proteins.
authors.affiliation: Laboratorium für Biochemie, Universität Bayreuth, Germany.
authors.forename: H P
authors.initials: HP
authors.lastname: Vornlocher
authors.forename: W R
authors.initials: WR
authors.lastname: Scheible
authors.forename: H G
authors.initials: HG
authors.lastname: Faulhammer
authors.forename: M
authors.initials: M
authors.lastname: Sprinzl
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000302:isolation & purification; D015153:Blotting, Western; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010442:Peptide Chain Initiation, Translational; D010448:Peptide Initiation Factors / Q000737:chemistry / Q000302:isolation & purification*; D010449:Peptide Mapping; D039881:Prokaryotic Initiation Factor-2; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D016963:Thermus thermophilus / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D010448:Peptide Initiation Factors; D039881:Prokaryotic Initiation Factor-2