ID   TOP1_HAEIN              Reviewed;         868 AA.
AC   P43012;
DT   01-NOV-1995, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1995, sequence version 1.
DT   27-MAR-2024, entry version 161.
DE   RecName: Full=DNA topoisomerase 1 {ECO:0000255|HAMAP-Rule:MF_00952};
DE            EC=5.6.2.1 {ECO:0000255|HAMAP-Rule:MF_00952};
DE   AltName: Full=DNA topoisomerase I {ECO:0000255|HAMAP-Rule:MF_00952};
DE   AltName: Full=Omega-protein;
DE   AltName: Full=Relaxing enzyme;
DE   AltName: Full=Swivelase;
DE   AltName: Full=Untwisting enzyme;
GN   Name=topA {ECO:0000255|HAMAP-Rule:MF_00952};
GN   OrderedLocusNames=HI_1365;
OS   Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd).
OC   Bacteria; Pseudomonadota; Gammaproteobacteria; Pasteurellales;
OC   Pasteurellaceae; Haemophilus.
OX   NCBI_TaxID=71421;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC   STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX   PubMed=8635745; DOI=10.1016/0378-1119(95)00777-6;
RA   Chandler M.S., Smith R.A.;
RT   "Characterization of the Haemophilus influenzae topA locus: DNA
RT   topoisomerase I is required for genetic competence.";
RL   Gene 169:25-31(1996).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 51907 / DSM 11121 / KW20 / Rd;
RX   PubMed=7542800; DOI=10.1126/science.7542800;
RA   Fleischmann R.D., Adams M.D., White O., Clayton R.A., Kirkness E.F.,
RA   Kerlavage A.R., Bult C.J., Tomb J.-F., Dougherty B.A., Merrick J.M.,
RA   McKenney K., Sutton G.G., FitzHugh W., Fields C.A., Gocayne J.D.,
RA   Scott J.D., Shirley R., Liu L.-I., Glodek A., Kelley J.M., Weidman J.F.,
RA   Phillips C.A., Spriggs T., Hedblom E., Cotton M.D., Utterback T.R.,
RA   Hanna M.C., Nguyen D.T., Saudek D.M., Brandon R.C., Fine L.D.,
RA   Fritchman J.L., Fuhrmann J.L., Geoghagen N.S.M., Gnehm C.L., McDonald L.A.,
RA   Small K.V., Fraser C.M., Smith H.O., Venter J.C.;
RT   "Whole-genome random sequencing and assembly of Haemophilus influenzae
RT   Rd.";
RL   Science 269:496-512(1995).
CC   -!- FUNCTION: Releases the supercoiling and torsional tension of DNA, which
CC       is introduced during the DNA replication and transcription, by
CC       transiently cleaving and rejoining one strand of the DNA duplex.
CC       Introduces a single-strand break via transesterification at a target
CC       site in duplex DNA. The scissile phosphodiester is attacked by the
CC       catalytic tyrosine of the enzyme, resulting in the formation of a DNA-
CC       (5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH
CC       DNA strand. The free DNA strand then undergoes passage around the
CC       unbroken strand, thus removing DNA supercoils. Finally, in the
CC       religation step, the DNA 3'-OH attacks the covalent intermediate to
CC       expel the active-site tyrosine and restore the DNA phosphodiester
CC       backbone. {ECO:0000255|HAMAP-Rule:MF_00952}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=ATP-independent breakage of single-stranded DNA, followed by
CC         passage and rejoining.; EC=5.6.2.1; Evidence={ECO:0000255|HAMAP-
CC         Rule:MF_00952};
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP-
CC         Rule:MF_00952};
CC   -!- SUBUNIT: Monomer. {ECO:0000255|HAMAP-Rule:MF_00952}.
CC   -!- SIMILARITY: Belongs to the type IA topoisomerase family.
CC       {ECO:0000255|HAMAP-Rule:MF_00952}.
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DR   EMBL; U20964; AAC43727.1; -; Genomic_DNA.
DR   EMBL; L42023; AAC23012.1; -; Genomic_DNA.
DR   PIR; G64119; G64119.
DR   RefSeq; NP_439516.1; NC_000907.1.
DR   AlphaFoldDB; P43012; -.
DR   SMR; P43012; -.
DR   STRING; 71421.HI_1365; -.
DR   EnsemblBacteria; AAC23012; AAC23012; HI_1365.
DR   KEGG; hin:HI_1365; -.
DR   PATRIC; fig|71421.8.peg.1419; -.
DR   eggNOG; COG0550; Bacteria.
DR   HOGENOM; CLU_002929_4_3_6; -.
DR   OrthoDB; 9804262at2; -.
DR   PhylomeDB; P43012; -.
DR   BioCyc; HINF71421:G1GJ1-1390-MONOMER; -.
DR   Proteomes; UP000000579; Chromosome.
DR   GO; GO:0005694; C:chromosome; IEA:InterPro.
DR   GO; GO:0003677; F:DNA binding; IEA:UniProtKB-KW.
DR   GO; GO:0003917; F:DNA topoisomerase type I (single strand cut, ATP-independent) activity; IEA:UniProtKB-UniRule.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0006265; P:DNA topological change; IEA:UniProtKB-UniRule.
DR   CDD; cd00186; TOP1Ac; 1.
DR   CDD; cd03363; TOPRIM_TopoIA_TopoI; 1.
DR   Gene3D; 2.20.25.10; -; 1.
DR   Gene3D; 3.40.50.140; -; 1.
DR   Gene3D; 3.30.65.10; Bacterial Topoisomerase I, domain 1; 3.
DR   Gene3D; 1.10.460.10; Topoisomerase I, domain 2; 1.
DR   Gene3D; 2.70.20.10; Topoisomerase I, domain 3; 1.
DR   Gene3D; 1.10.290.10; Topoisomerase I, domain 4; 1.
DR   HAMAP; MF_00952; Topoisom_1_prok; 1.
DR   InterPro; IPR049330; TOP1_Znf.
DR   InterPro; IPR000380; Topo_IA.
DR   InterPro; IPR003601; Topo_IA_2.
DR   InterPro; IPR023406; Topo_IA_AS.
DR   InterPro; IPR013497; Topo_IA_cen.
DR   InterPro; IPR013824; Topo_IA_cen_sub1.
DR   InterPro; IPR013825; Topo_IA_cen_sub2.
DR   InterPro; IPR013826; Topo_IA_cen_sub3.
DR   InterPro; IPR023405; Topo_IA_core_domain.
DR   InterPro; IPR003602; Topo_IA_DNA-bd_dom.
DR   InterPro; IPR013498; Topo_IA_Znf.
DR   InterPro; IPR005733; TopoI_bac-type.
DR   InterPro; IPR013263; TopoI_Znr_bac.
DR   InterPro; IPR028612; Topoisom_1_IA.
DR   InterPro; IPR006171; TOPRIM_domain.
DR   InterPro; IPR034149; TOPRIM_TopoI.
DR   NCBIfam; TIGR01051; topA_bact; 1.
DR   PANTHER; PTHR42785:SF1; DNA TOPOISOMERASE; 1.
DR   PANTHER; PTHR42785; DNA TOPOISOMERASE, TYPE IA, CORE; 1.
DR   Pfam; PF21372; TOP1_ZnF; 1.
DR   Pfam; PF08272; Topo_Zn_Ribbon; 2.
DR   Pfam; PF01131; Topoisom_bac; 1.
DR   Pfam; PF01751; Toprim; 1.
DR   Pfam; PF01396; zf-C4_Topoisom; 2.
DR   PRINTS; PR00417; PRTPISMRASEI.
DR   SMART; SM00437; TOP1Ac; 1.
DR   SMART; SM00436; TOP1Bc; 1.
DR   SMART; SM00493; TOPRIM; 1.
DR   SUPFAM; SSF56712; Prokaryotic type I DNA topoisomerase; 1.
DR   SUPFAM; SSF57783; Zinc beta-ribbon; 3.
DR   PROSITE; PS00396; TOPO_IA_1; 1.
DR   PROSITE; PS52039; TOPO_IA_2; 1.
DR   PROSITE; PS50880; TOPRIM; 1.
PE   3: Inferred from homology;
KW   DNA-binding; Isomerase; Magnesium; Metal-binding; Reference proteome;
KW   Repeat; Topoisomerase; Zinc; Zinc-finger.
FT   CHAIN           1..868
FT                   /note="DNA topoisomerase 1"
FT                   /id="PRO_0000145149"
FT   DOMAIN          3..148
FT                   /note="Toprim"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   DOMAIN          164..581
FT                   /note="Topo IA-type catalytic"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01383"
FT   ZN_FING         605..636
FT                   /note="C4-type 1"
FT   ZN_FING         667..694
FT                   /note="C4-type 2"
FT   ZN_FING         716..739
FT                   /note="C4-type 3"
FT   REGION          198..203
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   ACT_SITE        325
FT                   /note="O-(5'-phospho-DNA)-tyrosine intermediate"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01383"
FT   BINDING         9
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_note="catalytic"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   BINDING         117
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /ligand_note="catalytic"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            33
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            174
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            175
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            178
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            190
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            327
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   SITE            513
FT                   /note="Interaction with DNA"
FT                   /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT   CONFLICT        343
FT                   /note="T -> S (in Ref. 2; AAC23012)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   868 AA;  98144 MW;  AAD604BDEBC75D20 CRC64;
     MSKSLVIVES PAKAKTINKY LGSQYVVKSS VGHIRDLPTV GSSTGEKAKP ISTKGMDAEE
     KAKIKAEKER NALVKRMGID PYHDWKANYQ ILPGKEKVVS ELKSLAKKAD HIYLATDLDR
     EGEAIAWHLR EVIGGNDDRF SRVVFNEITK NAIKQAFEKP EQLNMDRVNA QQTRRFLDRV
     VGFMVSPLLW KKVARGLSAG RVQSVAVKLL VEREREIKAF QPEEYWEVAV LTNNQNKQAI
     RLDVTDYKGK KFDPKNQKEA QSAVDFLNVS DYVVTDLETK PTSSRPRAPF ITSTLQQTAS
     TRLGFGVKKT MMLAQRLYEA GYITYMRTDS TNLSQDALNM ARTYIENHFG AQYLPEKPNF
     YSSKENAQEA HEAIRPSDIR ALPESLEGME KDAVRLYDLI WCQFLACQMP PAQYDSSTLT
     VTAGDYTLKA KGRILRFDGW TKVLPQIGKN PEDQELPSVT VSEKLALKEV QPTQHFTKPP
     ARFTEAALVK ELEKRGIGRP STYAAIISTI QERGYVRTEN RRFYAEKMGE IVTDRLNESF
     GELMNYDFTA NMEDTLDKIA SGSVNWKTEL NQFFKDFSSQ LSKAELDELE GGMRPNSLVE
     TDIKCPTCGR NMAIRTASTG VFLGCTGYAL PPKERCKTTI NLIPEAELLN VLDESSETKA
     LMDRKRCTKC GTAMDSYVID AHRKIHICGN NPNCDGYLIE EGSFKIKGYD GPVVECDKCG
     ADMHLKLGRF GKYMGCTNCD NTRKILKNGE VAPPKEEPVH FPELKCEKSD AYFVLRDGAS
     GVFMSAHNFP KSRETRPVKI AELVQYRERL PEKLAYLADA PQKDPEENEA IVRFSRKEKK
     QYVTSEKEGK ATKWIVDFTN GKWVERKK
//