ID TOP3_BACCR Reviewed; 729 AA. AC Q81IH1; DT 01-MAY-2007, integrated into UniProtKB/Swiss-Prot. DT 01-JUN-2003, sequence version 1. DT 27-MAR-2024, entry version 116. 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=BC_0417; OS Bacillus cereus (strain ATCC 14579 / DSM 31 / CCUG 7414 / JCM 2152 / NBRC OS 15305 / NCIMB 9373 / NCTC 2599 / NRRL B-3711). OC Bacteria; Bacillota; Bacilli; Bacillales; Bacillaceae; Bacillus; OC Bacillus cereus group. OX NCBI_TaxID=226900; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=ATCC 14579 / DSM 31 / CCUG 7414 / JCM 2152 / NBRC 15305 / NCIMB RC 9373 / NCTC 2599 / NRRL B-3711; RX PubMed=12721630; DOI=10.1038/nature01582; RA Ivanova N., Sorokin A., Anderson I., Galleron N., Candelon B., Kapatral V., RA Bhattacharyya A., Reznik G., Mikhailova N., Lapidus A., Chu L., Mazur M., RA Goltsman E., Larsen N., D'Souza M., Walunas T., Grechkin Y., Pusch G., RA Haselkorn R., Fonstein M., Ehrlich S.D., Overbeek R., Kyrpides N.C.; RT "Genome sequence of Bacillus cereus and comparative analysis with Bacillus RT anthracis."; RL Nature 423:87-91(2003). 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; AE016877; AAP07457.1; -; Genomic_DNA. DR RefSeq; NP_830256.1; NC_004722.1. DR RefSeq; WP_000047293.1; NZ_CP034551.1. DR AlphaFoldDB; Q81IH1; -. DR SMR; Q81IH1; -. DR STRING; 226900.BC_0417; -. DR KEGG; bce:BC0417; -. DR PATRIC; fig|226900.8.peg.387; -. DR HOGENOM; CLU_002929_5_2_9; -. DR OrthoDB; 9803554at2; -. DR BRENDA; 5.6.2.1; 648. DR Proteomes; UP000001417; 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_0000286361" FT DOMAIN 3..136 FT /note="Toprim" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" FT DOMAIN 153..594 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 686..719 FT /note="Disordered" FT /evidence="ECO:0000256|SAM:MobiDB-lite" FT COMPBIAS 686..710 FT /note="Basic and acidic residues" FT /evidence="ECO:0000256|SAM:MobiDB-lite" FT ACT_SITE 310 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 312 FT /note="Interaction with DNA" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00953" SQ SEQUENCE 729 AA; 82891 MW; DDF62B294E1BB655 CRC64; MSKSVVIAEK PSVARDIARV LKCDKKGNGY LEGSKYIVTW ALGHLVTLAD PESYDVKYKK WNLEDLPMLP ERLKLTVIKQ TGKQFNAVKS QLLRKDVNEI IVATDAGREG ELVARWIIDK VKLNKPIKRL WISSVTDKAI KDGFANLKPG KAYDNLYASA VARSEADWYI GLNATRALTT RFNAQLNCGR VQTPTVAMIA SREDEIKNFK AQTYYGIEAQ TMEKLKLTWQ DANGNSRSFN KEKIDGIVKR LDKQNATVVE IDKKQKKSFS PGLYDLTELQ RDANKKFGYS AKETLNIMQK LYEQHKVLTY PRTDSRYISS DIVGTLPERL KACGVGEYRP FAHKVLQKPI KPNKSFVDDS KVSDHHAIIP TEGYVNFSAF TDKERKIYDL VVKRFLAVLF PAFEYEQLTL RTKVGNETFI ARGKTILHAG WKEVYENRFE DDDVTDDVKE QLLPHIEKGD TLAVKLIMQT SGQTKAPARF NEATLLSAME NPTKYMDTQN KQLADTLKST GGLGTVATRA DIIDKLFNSF LIEKRGKDIH ITSKGRQLLD LVPEELKSPT LTGEWEQKLE AIAKGKLKKE VFISEMKNYT KEIVSEIKSS DKKYKHDNIS TKSCPDCGKP MLEVNGKKGK MLVCQDRECG HRKNVSRTTN ARCPQCKKKL ELRGEGAGQI FACKCGYREK LSTFQERRKK ESGNKADKRD VQKYMKQQNK EEEPLNNPFA EALKKLKFD //