ID TOP3_SHOC1 Reviewed; 729 AA. AC Q5WAX6; DT 01-MAY-2007, integrated into UniProtKB/Swiss-Prot. DT 23-NOV-2004, sequence version 1. DT 27-MAR-2024, entry version 112. DE RecName: Full=DNA topoisomerase 3 {ECO:0000255|HAMAP-Rule:MF_00953}; DE EC=5.6.2.1 {ECO:0000255|HAMAP-Rule:MF_00953}; DE AltName: Full=DNA topoisomerase III {ECO:0000255|HAMAP-Rule:MF_00953}; GN Name=topB {ECO:0000255|HAMAP-Rule:MF_00953}; GN OrderedLocusNames=ABC3953; OS Shouchella clausii (strain KSM-K16) (Alkalihalobacillus clausii). OC Bacteria; Bacillota; Bacilli; Bacillales; Bacillaceae; Shouchella. OX NCBI_TaxID=66692; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=KSM-K16; RA Takaki Y., Kageyama Y., Shimamura S., Suzuki H., Nishi S., Hatada Y., RA Kawai S., Ito S., Horikoshi K.; RT "The complete genome sequence of the alkaliphilic Bacillus clausii KSM- RT K16."; RL Submitted (OCT-2003) to the EMBL/GenBank/DDBJ databases. 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_00953}. 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_00953}; CC -!- COFACTOR: CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP- CC Rule:MF_00953}; CC -!- SIMILARITY: Belongs to the type IA topoisomerase family. CC {ECO:0000255|HAMAP-Rule:MF_00953, ECO:0000255|PROSITE- CC ProRule:PRU01383}. 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; AP006627; BAD66484.1; -; Genomic_DNA. DR RefSeq; WP_011248787.1; NC_006582.1. DR AlphaFoldDB; Q5WAX6; -. DR SMR; Q5WAX6; -. DR STRING; 66692.ABC3953; -. DR KEGG; bcl:ABC3953; -. DR eggNOG; COG0550; Bacteria. DR eggNOG; COG0551; Bacteria. DR HOGENOM; CLU_002929_5_2_9; -. DR OrthoDB; 9803554at2; -. DR Proteomes; UP000001168; 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:0000287; F:magnesium ion binding; IEA:UniProtKB-UniRule. DR GO; GO:0006265; P:DNA topological change; IEA:UniProtKB-UniRule. DR CDD; cd00186; TOP1Ac; 1. DR CDD; cd03362; TOPRIM_TopoIA_TopoIII; 1. DR Gene3D; 3.40.50.140; -; 1. 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_00953; Topoisom_3_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; IPR005738; TopoIII. DR InterPro; IPR006171; TOPRIM_domain. DR InterPro; IPR034144; TOPRIM_TopoIII. DR NCBIfam; TIGR01056; topB; 1. DR PANTHER; PTHR11390:SF21; DNA TOPOISOMERASE 3-ALPHA; 1. DR PANTHER; PTHR11390; PROKARYOTIC DNA TOPOISOMERASE; 1. 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; Prokaryotic type I DNA topoisomerase; 1. 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 Topoisomerase. FT CHAIN 1..729 FT /note="DNA topoisomerase 3" FT /id="PRO_0000286365" FT DOMAIN 3..136 FT /note="Toprim" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT DOMAIN 153..590 FT /note="Topo IA-type catalytic" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01383" FT REGION 187..192 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT REGION 680..708 FT /note="Disordered" FT /evidence="ECO:0000256|SAM:MobiDB-lite" FT COMPBIAS 680..702 FT /note="Basic and acidic residues" FT /evidence="ECO:0000256|SAM:MobiDB-lite" FT ACT_SITE 311 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_00953" FT BINDING 105 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_note="catalytic" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT SITE 61 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT SITE 168 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT SITE 176 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT SITE 313 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" SQ SEQUENCE 729 AA; 82115 MW; 538DCA474A448178 CRC64; MKKKAVLAEK PSVARDIARV LGCNQKGNGY LEGNGYIITW ALGHLVTHAD PEHYGKQYKT WKLEELPMLP KRLELVVIKQ TAKQFHAVKH VLNRQDVGEV VIATDAGREG ELVARWILEK AHVKKPVKRL WISSVTDKAI KDGFKQLKDG KRYETLYAAA AARAEADWYV GINGTRALTT KHNAQLSCGR VQTPTLAILA DREEAIRKFV PKPYHTISVE TKDGVTFRWA DRRSKEERIF DDKRAKTLQE KLQQSAIVID SVNAKTKRTP PPPLYDLTEL QREANKRFGY SAKETLAALQ RLYEQHKAVT YPRTDSRYLS SDLVETLKER LHAVDVQPFR KMVANAKKQG LANAKRQMVN DAKVSDHHAL IPTEQPQSAS AMSDKEAKLY HLIVRRFLAN FFPPSESELT SVEATANGEL LRAKGERLVS AGWRGQETGE EDEALARLLP AMSKGDKKAV KWVGMTQGKT SPPPRFNEGT LLAAMEKPAQ HMEAKDETIK KTLAQAGGIG TVATRADIIE KLFSSFYIEK KGKDLYITSK GKQLLELVPA ELKSPALTAE WEQRLEKIVQ GKEQKQMFIA EMKEYAKAVV AQVKADTATF RHDNKTGEKC PECGKFLLEV NGKKGKMRVC QDRECGYRKN IAMTTNARCP KCKKKLELRG EGEGQVFACV CGHREKKAQF EQRRKQNKHK NVSKREVQSY MKKQNKQDQF ANSALADQLA KLGLKGDDS //