ID   IF3_GEOSE               Reviewed;         172 AA.
AC   P03000;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 2.
DT   25-MAY-2022, entry version 112.
DE   RecName: Full=Translation initiation factor IF-3 {ECO:0000255|HAMAP-Rule:MF_00080};
GN   Name=infC {ECO:0000255|HAMAP-Rule:MF_00080};
OS   Geobacillus stearothermophilus (Bacillus stearothermophilus).
OC   Bacteria; Firmicutes; Bacilli; Bacillales; Bacillaceae; Geobacillus.
OX   NCBI_TaxID=1422;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=2779520; DOI=10.1007/bf00331290;
RA   Pon C.L., Brombach M., Thamm S., Gualerzi C.O.;
RT   "Cloning and characterization of a gene cluster from Bacillus
RT   stearothermophilus comprising infC, rpmI and rplT.";
RL   Mol. Gen. Genet. 218:355-357(1989).
RN   [2]
RP   PROTEIN SEQUENCE OF 2-172.
RC   STRAIN=ATCC 29609 / DSM 2027 / NCA 1503 / NCIMB 8924;
RX   PubMed=6884517; DOI=10.1016/0014-5793(83)80940-5;
RA   Kimura M., Ernst H., Appelt K.;
RT   "The primary structure of initiation factor IF3 from Bacillus
RT   stearothermophilus.";
RL   FEBS Lett. 160:78-81(1983).
RN   [3]
RP   STRUCTURE BY NMR, AND MUTAGENESIS.
RX   PubMed=1742345; DOI=10.1016/0300-9084(91)90141-m;
RA   Spurio R., Paci M., Pawlik R.T., la Teana A., Digiacco B.V., Pon C.L.,
RA   Gualerzi C.O.;
RT   "Site-directed mutagenesis and NMR spectroscopic approaches to the
RT   elucidation of the structure-function relationships in translation
RT   initiation factors IF1 and IF3.";
RL   Biochimie 73:1001-1006(1991).
RN   [4]
RP   STRUCTURE BY NMR.
RX   PubMed=9614948; DOI=10.1006/jmbi.1998.1736;
RA   Hua Y., Raleigh D.P.;
RT   "On the global architecture of initiation factor IF3: a comparative study
RT   of the linker regions from the Escherichia coli protein and the Bacillus
RT   stearothermophilus protein.";
RL   J. Mol. Biol. 278:871-878(1998).
RN   [5]
RP   X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS).
RX   PubMed=7664745; DOI=10.1002/j.1460-2075.1995.tb00077.x;
RA   Biou V., Shu F., Ramakrishnan V.;
RT   "X-ray crystallography shows that translational initiation factor IF3
RT   consists of two compact alpha/beta domains linked by an alpha-helix.";
RL   EMBO J. 14:4056-4064(1995).
CC   -!- FUNCTION: IF-3 binds to the 30S ribosomal subunit and shifts the
CC       equilibrum between 70S ribosomes and their 50S and 30S subunits in
CC       favor of the free subunits, thus enhancing the availability of 30S
CC       subunits on which protein synthesis initiation begins.
CC   -!- SUBUNIT: Monomer.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm.
CC   -!- SIMILARITY: Belongs to the IF-3 family. {ECO:0000255|HAMAP-
CC       Rule:MF_00080}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; X16188; CAA34312.1; -; Genomic_DNA.
DR   PIR; S05346; FIBS3F.
DR   PDB; 1TIF; X-ray; 1.80 A; A=1-78.
DR   PDB; 1TIG; X-ray; 2.00 A; A=79-172.
DR   PDB; 5ME0; EM; 13.50 A; Y=2-172.
DR   PDB; 5ME1; EM; 13.50 A; Y=2-172.
DR   PDBsum; 1TIF; -.
DR   PDBsum; 1TIG; -.
DR   PDBsum; 5ME0; -.
DR   PDBsum; 5ME1; -.
DR   AlphaFoldDB; P03000; -.
DR   SMR; P03000; -.
DR   IntAct; P03000; 1.
DR   EvolutionaryTrace; P03000; -.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0003743; F:translation initiation factor activity; IEA:UniProtKB-UniRule.
DR   Gene3D; 3.10.20.80; -; 1.
DR   Gene3D; 3.30.110.10; -; 1.
DR   HAMAP; MF_00080; IF_3; 1.
DR   InterPro; IPR036788; T_IF-3_C_sf.
DR   InterPro; IPR036787; T_IF-3_N_sf.
DR   InterPro; IPR019813; Translation_initiation_fac3_CS.
DR   InterPro; IPR001288; Translation_initiation_fac_3.
DR   InterPro; IPR019815; Translation_initiation_fac_3_C.
DR   InterPro; IPR019814; Translation_initiation_fac_3_N.
DR   PANTHER; PTHR10938; PTHR10938; 1.
DR   Pfam; PF00707; IF3_C; 1.
DR   Pfam; PF05198; IF3_N; 1.
DR   SUPFAM; SSF54364; SSF54364; 1.
DR   SUPFAM; SSF55200; SSF55200; 1.
DR   TIGRFAMs; TIGR00168; infC; 1.
DR   PROSITE; PS00938; IF3; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Cytoplasm; Direct protein sequencing; Initiation factor;
KW   Protein biosynthesis.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000269|PubMed:6884517"
FT   CHAIN           2..172
FT                   /note="Translation initiation factor IF-3"
FT                   /id="PRO_0000177481"
FT   HELIX           8..10
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          14..19
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          25..30
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   HELIX           31..40
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          44..49
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          52..54
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          56..60
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   HELIX           62..75
FT                   /evidence="ECO:0007829|PDB:1TIF"
FT   STRAND          85..90
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   HELIX           96..111
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   STRAND          115..121
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   HELIX           129..143
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   TURN            144..147
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   STRAND          148..157
FT                   /evidence="ECO:0007829|PDB:1TIG"
FT   STRAND          160..168
FT                   /evidence="ECO:0007829|PDB:1TIG"
SQ   SEQUENCE   172 AA;  19809 MW;  379902B302ECD929 CRC64;
     MSKDFIINEQ IRAREVRLID QNGDQLGIKS KQEALEIAAR RNLDLVLVAP NAKPPVCRIM
     DYGKFRFEQQ KKEKEARKKQ KVINVKEVRL SPTIEEHDFN TKLRNARKFL EKGDKVKATI
     RFKGRAITHK EIGQRVLDRL SEACADIAVV ETAPKMDGRN MFLVLAPKND NK