TOP1_BUCAP
ID TOP1_BUCAP Reviewed; 853 AA.
AC Q8K9P7;
DT 08-NOV-2002, integrated into UniProtKB/Swiss-Prot.
DT 01-OCT-2002, sequence version 1.
DT 03-AUG-2022, entry version 129.
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}; OrderedLocusNames=BUsg_273;
OS Buchnera aphidicola subsp. Schizaphis graminum (strain Sg).
OC Bacteria; Proteobacteria; Gammaproteobacteria; Enterobacterales;
OC Erwiniaceae; Buchnera.
OX NCBI_TaxID=198804;
RN [1]
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=Sg;
RX PubMed=12089438; DOI=10.1126/science.1071278;
RA Tamas I., Klasson L., Canbaeck B., Naeslund A.K., Eriksson A.-S.,
RA Wernegreen J.J., Sandstroem J.P., Moran N.A., Andersson S.G.E.;
RT "50 million years of genomic stasis in endosymbiotic bacteria.";
RL Science 296:2376-2379(2002).
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;
CC Evidence={ECO:0000255|HAMAP-Rule:MF_00952};
CC Note=Binds two Mg(2+) per subunit. {ECO:0000255|HAMAP-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; AE013218; AAM67831.1; -; Genomic_DNA.
DR RefSeq; WP_011053798.1; NC_004061.1.
DR AlphaFoldDB; Q8K9P7; -.
DR SMR; Q8K9P7; -.
DR STRING; 198804.BUsg_273; -.
DR EnsemblBacteria; AAM67831; AAM67831; BUsg_273.
DR KEGG; bas:BUsg_273; -.
DR eggNOG; COG0550; Bacteria.
DR HOGENOM; CLU_002929_4_3_6; -.
DR OMA; PECKYTR; -.
DR OrthoDB; 223233at2; -.
DR Proteomes; UP000000416; Chromosome.
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 Gene3D; 1.10.290.10; -; 1.
DR Gene3D; 1.10.460.10; -; 1.
DR Gene3D; 2.70.20.10; -; 1.
DR HAMAP; MF_00952; Topoisom_1_prok; 1.
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; IPR005733; TopoI_bac-type.
DR InterPro; IPR013263; TopoI_Znr_bac.
DR InterPro; IPR028612; Topoisom_1_IA.
DR InterPro; IPR006171; TOPRIM_domain.
DR PANTHER; PTHR42785; PTHR42785; 1.
DR Pfam; PF08272; Topo_Zn_Ribbon; 2.
DR Pfam; PF01131; Topoisom_bac; 1.
DR Pfam; PF01751; Toprim; 1.
DR PRINTS; PR00417; PRTPISMRASEI.
DR SMART; SM00437; TOP1Ac; 1.
DR SMART; SM00436; TOP1Bc; 1.
DR SMART; SM00493; TOPRIM; 1.
DR SUPFAM; SSF56712; SSF56712; 1.
DR TIGRFAMs; TIGR01051; topA_bact; 1.
DR PROSITE; PS00396; TOPOISOMERASE_I_PROK; 1.
DR PROSITE; PS50880; TOPRIM; 1.
PE 3: Inferred from homology;
KW DNA-binding; Isomerase; Magnesium; Metal-binding; Repeat; Topoisomerase;
KW Zinc; Zinc-finger.
FT CHAIN 1..853
FT /note="DNA topoisomerase 1"
FT /id="PRO_0000145145"
FT DOMAIN 3..136
FT /note="Toprim"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT ZN_FING 589..621
FT /note="C4-type 1"
FT ZN_FING 649..676
FT /note="C4-type 2"
FT ZN_FING 699..724
FT /note="C4-type 3"
FT REGION 186..191
FT /note="Interaction with DNA"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT ACT_SITE 313
FT /note="O-(5'-phospho-DNA)-tyrosine intermediate"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT BINDING 9
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT BINDING 105
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /ligand_note="catalytic"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT BINDING 105
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT BINDING 107
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
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 162
FT /note="Interaction with DNA"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT SITE 163
FT /note="Interaction with DNA"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT SITE 166
FT /note="Interaction with DNA"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
FT SITE 171
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 315
FT /note="Interaction with DNA"
FT /evidence="ECO:0000255|HAMAP-Rule:MF_00952"
SQ SEQUENCE 853 AA; 98816 MW; 99B454AB78AC6D1B CRC64;
MCKSLVIVES PVKAKTISKY LGKQYIVKSS VGHVRDLINN KSKNKKNIKK SNIKHNEKTA
LIQQMGINPY KNWKAEYHIL PGKEKIISEL KNIANKVHYI YLATDLDREG EAIAWHLKEV
IGGNSLKFRR VVFNEITKKS IEKAFQNIGK INMNRVYSQQ ARRFMDRIVG YMISPLLWKK
ISRGLSAGRV QSAAVRLITD REYEIKNFIE REHWKISLSL LSKENKKVTM DITHYRNKTF
LLNNKKEVNS TIEKIKNLSF IITDRKDKIF KKKPPAPLIT STLQQASNID LGFSVKKTMF
LAQKLYEQGY ITYIRTDSYF LSNYAIEKVR SYIENFYGSD FLPKKSNIYS NQKYSQEAHE
AIRPSDVQVV NIDNCDPDAK KLYKLIWNYF IASQMKSERY KSIKTTVMAD VFKLQSNTKI
VLFSGWTKIL KKSNNVNFKF PVLDIGTTLI LDKILPHQIF TKPPPRFSES SLVRELEKKG
IGRPSTYATI ITKIKEKGYL KIKKNKFYAA KIGEILITRL KKNFSDLVDY DFTARMEKNL
DQVSDKLINW KHLLNSFFDN FSQQLEQAKK PPEEGGMELN TTVPTEIDCS LCNKKMGIKT
AVTGVFLSCL GYNSEPNEKR CKNTINLISL NDLSTTKKEE KNFHLKNRCK KCNLVMDVYL
INENLKIFIC INNPSCNGYN LKKGIFKKSL NCSLKKIKCE KCKNDMLFKT GRFGNFFMCI
NDTCKNTRKI LPNGEISEPK FEPIPFPDIL CEKSNTWFVL REGISGIFFA ANTFPKSRET
RSPFVEELAR FEYLLPKKLH YLASAPQRDN KGNKTIVCFN KLNKQQYIAS KKEGKFTGWA
AFFIDRKWCI VNK
