IHFA_ECOLI
ID IHFA_ECOLI Reviewed; 99 AA.
AC P0A6X7; P06984;
DT 01-APR-1988, integrated into UniProtKB/Swiss-Prot.
DT 01-APR-1988, sequence version 1.
DT 03-AUG-2022, entry version 139.
DE RecName: Full=Integration host factor subunit alpha;
DE Short=IHF-alpha;
GN Name=ihfA; Synonyms=hid, himA; OrderedLocusNames=b1712, JW1702;
OS Escherichia coli (strain K12).
OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC Enterobacteriaceae; Escherichia.
OX NCBI_TaxID=83333;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=6397321; DOI=10.1101/sqb.1984.049.01.078;
RA Miller H.I.;
RT "Primary structure of the himA gene of Escherichia coli: homology with DNA-
RT binding protein HU and association with the phenylalanyl-tRNA synthetase
RT operon.";
RL Cold Spring Harb. Symp. Quant. Biol. 49:691-698(1984).
RN [2]
RP SEQUENCE REVISION.
RA Miller H.I.;
RL Submitted (AUG-1985) to the EMBL/GenBank/DDBJ databases.
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX PubMed=2991205; DOI=10.1128/jb.163.2.787-791.1985;
RA Mechulman Y., Fayat G., Blanquet S.;
RT "Sequence of the Escherichia coli pheST operon and identification of the
RT himA gene.";
RL J. Bacteriol. 163:787-791(1985).
RN [4]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX PubMed=9097039; DOI=10.1093/dnares/3.6.363;
RA Aiba H., Baba T., Fujita K., Hayashi K., Inada T., Isono K., Itoh T.,
RA Kasai H., Kashimoto K., Kimura S., Kitakawa M., Kitagawa M., Makino K.,
RA Miki T., Mizobuchi K., Mori H., Mori T., Motomura K., Nakade S.,
RA Nakamura Y., Nashimoto H., Nishio Y., Oshima T., Saito N., Sampei G.,
RA Seki Y., Sivasundaram S., Tagami H., Takeda J., Takemoto K., Takeuchi Y.,
RA Wada C., Yamamoto Y., Horiuchi T.;
RT "A 570-kb DNA sequence of the Escherichia coli K-12 genome corresponding to
RT the 28.0-40.1 min region on the linkage map.";
RL DNA Res. 3:363-377(1996).
RN [5]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=K12 / MG1655 / ATCC 47076;
RX PubMed=9278503; DOI=10.1126/science.277.5331.1453;
RA Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V.,
RA Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F.,
RA Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B.,
RA Shao Y.;
RT "The complete genome sequence of Escherichia coli K-12.";
RL Science 277:1453-1462(1997).
RN [6]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX PubMed=16738553; DOI=10.1038/msb4100049;
RA Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S.,
RA Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.;
RT "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655
RT and W3110.";
RL Mol. Syst. Biol. 2:E1-E5(2006).
RN [7]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 83-99.
RX PubMed=3528129; DOI=10.1128/jb.167.3.928-934.1986;
RA Friedrich M.J., Deveaux L.C., Kadner R.J.;
RT "Nucleotide sequence of the btuCED genes involved in vitamin B12 transport
RT in Escherichia coli and homology with components of periplasmic-binding-
RT protein-dependent transport systems.";
RL J. Bacteriol. 167:928-934(1986).
RN [8]
RP PROTEIN SEQUENCE OF 2-11.
RC STRAIN=K12;
RX PubMed=9868784; DOI=10.1111/j.1574-6968.1998.tb13343.x;
RA Wasinger V.C., Humphery-Smith I.;
RT "Small genes/gene-products in Escherichia coli K-12.";
RL FEMS Microbiol. Lett. 169:375-382(1998).
RN [9]
RP MUTAGENESIS.
RX PubMed=1531459; DOI=10.1002/j.1460-2075.1992.tb05053.x;
RA Lee E.C., Hales L.M., Gumport R.I., Gardner J.F.;
RT "The isolation and characterization of mutants of the integration host
RT factor (IHF) of Escherichia coli with altered, expanded DNA-binding
RT specificities.";
RL EMBO J. 11:305-313(1992).
RN [10]
RP FUNCTION IN CONJUGATION, AND FUNCTION IN F PLASMID NICKING.
RX PubMed=7499339; DOI=10.1074/jbc.270.47.28381;
RA Nelson W.C., Howard M.T., Sherman J.A., Matson S.W.;
RT "The traY gene product and integration host factor stimulate Escherichia
RT coli DNA helicase I-catalyzed nicking at the F plasmid oriT.";
RL J. Biol. Chem. 270:28374-28380(1995).
RN [11]
RP CHARACTERIZATION OF RELAXOSOME ASSEMBLY ORDER, AND SUBUNIT.
RX PubMed=7499340; DOI=10.1074/jbc.270.47.28374;
RA Howard M.T., Nelson W.C., Matson S.W.;
RT "Stepwise assembly of a relaxosome at the F plasmid origin of transfer.";
RL J. Biol. Chem. 270:28381-28386(1995).
RN [12]
RP IDENTIFICATION BY 2D-GEL.
RX PubMed=9298644; DOI=10.1002/elps.1150180805;
RA VanBogelen R.A., Abshire K.Z., Moldover B., Olson E.R., Neidhardt F.C.;
RT "Escherichia coli proteome analysis using the gene-protein database.";
RL Electrophoresis 18:1243-1251(1997).
RN [13]
RP FUNCTION, AND DNA-BINDING.
RC STRAIN=K12 / MG1655 / ATCC 47076;
RX PubMed=16963779; DOI=10.1093/nar/gkl542;
RA Grainger D.C., Hurd D., Goldberg M.D., Busby S.J.;
RT "Association of nucleoid proteins with coding and non-coding segments of
RT the Escherichia coli genome.";
RL Nucleic Acids Res. 34:4642-4652(2006).
RN [14]
RP FUNCTION IN CONJUGATION, DNA-BINDING, AND SUBUNIT.
RX PubMed=17238924; DOI=10.1111/j.1365-2958.2006.05576.x;
RA Ragonese H., Haisch D., Villareal E., Choi J.H., Matson S.W.;
RT "The F plasmid-encoded TraM protein stimulates relaxosome-mediated cleavage
RT at oriT through an interaction with TraI.";
RL Mol. Microbiol. 63:1173-1184(2007).
RN [15]
RP SUBCELLULAR LOCATION.
RC STRAIN=K12 / BW25993;
RX PubMed=21903814; DOI=10.1126/science.1204697;
RA Wang W., Li G.W., Chen C., Xie X.S., Zhuang X.;
RT "Chromosome organization by a nucleoid-associated protein in live
RT bacteria.";
RL Science 333:1445-1449(2011).
RN [16]
RP X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS).
RX PubMed=8980235; DOI=10.1016/s0092-8674(00)81824-3;
RA Rice P.A., Yang S., Mizuuchi K., Nash H.A.;
RT "Crystal structure of an IHF-DNA complex: a protein-induced DNA U-turn.";
RL Cell 87:1295-1306(1996).
CC -!- FUNCTION: One of the 2 subunits of integration host factor (IHF), a
CC specific DNA-binding protein that functions in genetic recombination as
CC well as in transcriptional and translational control. Binds to hundreds
CC of transcriptionally inactive, AT-rich DNA sites, approximately half
CC its binding sites are in non-coding DNA, which only accounts for about
CC 10% of the genome (PubMed:16963779). {ECO:0000269|PubMed:16963779}.
CC -!- FUNCTION: Plays a crucial role in the lysogenic life cycle of
CC bacteriophage lambda, as it is required not only in the recombination
CC reaction, which inserts lambda DNA into the E.coli chromosome, but also
CC for the synthesis of int and cI repressor, two phage proteins necessary
CC for DNA insertion and repression, respectively. The synthesis of int
CC and cI proteins is regulated indirectly by IHF via translational
CC control of the lambda cII protein.
CC -!- FUNCTION: Has an essential role in conjugative DNA transfer (CDT), the
CC unidirectional transfer of ssDNA plasmid from a donor to a recipient
CC cell. It is the central mechanism by which antibiotic resistance and
CC virulence factors are propagated in bacterial populations. Part of the
CC relaxosome, which facilitates a site- and strand-specific cut in the
CC origin of transfer by TraI, at the nic site. Relaxosome formation
CC requires binding of IHF and TraY to the oriT region, which then
CC facilitates binding of TraI.
CC -!- SUBUNIT: Heterodimer of an alpha and a beta chain. Part of the
CC relaxosome, a complex composed of plasmid-encoded TraI, TraM, TraY and
CC host-encoded IHF bound to the F plasmid origin of transfer (oriT).
CC {ECO:0000269|PubMed:17238924, ECO:0000269|PubMed:7499340}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm, nucleoid
CC {ECO:0000269|PubMed:21903814}. Note=Scattered throughout the nucleoid
CC (PubMed:21903814). {ECO:0000269|PubMed:21903814}.
CC -!- SIMILARITY: Belongs to the bacterial histone-like protein family.
CC {ECO:0000305}.
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; K02844; AAA51471.1; -; Genomic_DNA.
DR EMBL; V00291; CAA23566.1; -; Genomic_DNA.
DR EMBL; U00096; AAC74782.1; -; Genomic_DNA.
DR EMBL; AP009048; BAA15480.1; -; Genomic_DNA.
DR EMBL; M14031; AAA23525.1; -; Genomic_DNA.
DR PIR; C23099; IQECAA.
DR RefSeq; NP_416227.1; NC_000913.3.
DR RefSeq; WP_001229265.1; NZ_STEB01000009.1.
DR PDB; 1IHF; X-ray; 2.20 A; A=1-99.
DR PDB; 1OUZ; X-ray; 2.41 A; A=1-99.
DR PDB; 1OWF; X-ray; 1.95 A; A=1-99.
DR PDB; 1OWG; X-ray; 2.10 A; A=1-99.
DR PDB; 2HT0; X-ray; 2.00 A; A=1-99.
DR PDB; 2IIE; X-ray; 2.41 A; A=3-94.
DR PDB; 2IIF; X-ray; 2.72 A; A=3-94.
DR PDB; 5J0N; EM; 11.00 A; I/K=2-97.
DR PDBsum; 1IHF; -.
DR PDBsum; 1OUZ; -.
DR PDBsum; 1OWF; -.
DR PDBsum; 1OWG; -.
DR PDBsum; 2HT0; -.
DR PDBsum; 2IIE; -.
DR PDBsum; 2IIF; -.
DR PDBsum; 5J0N; -.
DR AlphaFoldDB; P0A6X7; -.
DR SMR; P0A6X7; -.
DR BioGRID; 4260284; 205.
DR BioGRID; 849846; 1.
DR ComplexPortal; CPX-1957; Integration host factor complex.
DR DIP; DIP-36031N; -.
DR IntAct; P0A6X7; 24.
DR STRING; 511145.b1712; -.
DR jPOST; P0A6X7; -.
DR PaxDb; P0A6X7; -.
DR PRIDE; P0A6X7; -.
DR EnsemblBacteria; AAC74782; AAC74782; b1712.
DR EnsemblBacteria; BAA15480; BAA15480; BAA15480.
DR GeneID; 67415582; -.
DR GeneID; 945472; -.
DR KEGG; ecj:JW1702; -.
DR KEGG; eco:b1712; -.
DR PATRIC; fig|1411691.4.peg.545; -.
DR EchoBASE; EB0435; -.
DR eggNOG; COG0776; Bacteria.
DR HOGENOM; CLU_105066_1_3_6; -.
DR InParanoid; P0A6X7; -.
DR OMA; IYVRGFG; -.
DR PhylomeDB; P0A6X7; -.
DR BioCyc; EcoCyc:PD00347; -.
DR EvolutionaryTrace; P0A6X7; -.
DR PRO; PR:P0A6X7; -.
DR Proteomes; UP000000318; Chromosome.
DR Proteomes; UP000000625; Chromosome.
DR CollecTF; EXPREG_00000780; -.
DR GO; GO:0005829; C:cytosol; IDA:EcoCyc.
DR GO; GO:1990177; C:IHF-DNA complex; IPI:ComplexPortal.
DR GO; GO:0032993; C:protein-DNA complex; IPI:CollecTF.
DR GO; GO:0003677; F:DNA binding; IBA:GO_Central.
DR GO; GO:0001216; F:DNA-binding transcription activator activity; IPI:CollecTF.
DR GO; GO:0030527; F:structural constituent of chromatin; IEA:InterPro.
DR GO; GO:0000976; F:transcription cis-regulatory region binding; IPI:CollecTF.
DR GO; GO:0006310; P:DNA recombination; IEA:UniProtKB-UniRule.
DR GO; GO:0006417; P:regulation of translation; IC:ComplexPortal.
DR GO; GO:0006351; P:transcription, DNA-templated; IDA:EcoCyc.
DR CDD; cd13835; IHF_A; 1.
DR Gene3D; 4.10.520.10; -; 1.
DR HAMAP; MF_00380; IHF_alpha; 1.
DR InterPro; IPR000119; Hist_DNA-bd.
DR InterPro; IPR020816; Histone-like_DNA-bd_CS.
DR InterPro; IPR010992; IHF-like_DNA-bd_dom_sf.
DR InterPro; IPR005684; IHF_alpha.
DR PANTHER; PTHR33175; PTHR33175; 1.
DR Pfam; PF00216; Bac_DNA_binding; 1.
DR PRINTS; PR01727; DNABINDINGHU.
DR SMART; SM00411; BHL; 1.
DR SUPFAM; SSF47729; SSF47729; 1.
DR TIGRFAMs; TIGR00987; himA; 1.
DR PROSITE; PS00045; HISTONE_LIKE; 1.
PE 1: Evidence at protein level;
KW 3D-structure; Conjugation; Cytoplasm; Direct protein sequencing;
KW DNA recombination; DNA-binding; Reference proteome; Transcription;
KW Transcription regulation; Translation regulation.
FT INIT_MET 1
FT /note="Removed"
FT /evidence="ECO:0000269|PubMed:9868784"
FT CHAIN 2..99
FT /note="Integration host factor subunit alpha"
FT /id="PRO_0000105005"
FT REGION 49..73
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT MUTAGEN 65
FT /note="P->L: Alters DNA-binding specificity."
FT /evidence="ECO:0000269|PubMed:1531459"
FT MUTAGEN 66
FT /note="K->S: Alters DNA-binding specificity."
FT /evidence="ECO:0000269|PubMed:1531459"
FT HELIX 5..16
FT /evidence="ECO:0007829|PDB:1OWF"
FT HELIX 20..39
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 44..46
FT /evidence="ECO:0007829|PDB:1OWF"
FT TURN 47..49
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 50..57
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 60..63
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 65..67
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 70..73
FT /evidence="ECO:0007829|PDB:1OWF"
FT STRAND 76..83
FT /evidence="ECO:0007829|PDB:1OWF"
FT HELIX 85..92
FT /evidence="ECO:0007829|PDB:1OWF"
SQ SEQUENCE 99 AA; 11354 MW; 278AC82BCD79D754 CRC64;
MALTKAEMSE YLFDKLGLSK RDAKELVELF FEEIRRALEN GEQVKLSGFG NFDLRDKNQR
PGRNPKTGED IPITARRVVT FRPGQKLKSR VENASPKDE
