Skip Header

You are using a version of Internet Explorer that may not display all features of this website. Please upgrade to a modern browser.
Contribute Send feedback
Read comments (?) or add your own

Q9X909 (TOP1_STRCO) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 98. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
DNA topoisomerase 1

EC=5.99.1.2
Alternative name(s):
DNA topoisomerase I
Omega-protein
Relaxing enzyme
Swivelase
Untwisting enzyme
Gene names
Name:topA
Ordered Locus Names:SCO3543
ORF Names:SCH5.06c
OrganismStreptomyces coelicolor (strain ATCC BAA-471 / A3(2) / M145) [Reference proteome] [HAMAP]
Taxonomic identifier100226 [NCBI]
Taxonomic lineageBacteriaActinobacteriaActinobacteridaeActinomycetalesStreptomycineaeStreptomycetaceaeStreptomycesStreptomyces albidoflavus group

Protein attributes

Sequence length952 AA.
Sequence statusComplete.
Protein existenceInferred from homology

General annotation (Comments)

Function

Releases the supercoiling and torsional tension of DNA, which is introduced during the DNA replication and transcription, by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand, thus removing DNA supercoils. Finally, in the religation step, the DNA 3'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone By similarity. HAMAP-Rule MF_00952

Catalytic activity

ATP-independent breakage of single-stranded DNA, followed by passage and rejoining. HAMAP-Rule MF_00952

Cofactor

Magnesium. Binds two Mg2+ per subunit By similarity. HAMAP-Rule MF_00952

Subunit structure

Monomer By similarity. HAMAP-Rule MF_00952

Sequence similarities

Belongs to the type IA topoisomerase family.

Contains 1 Toprim domain.

Ontologies

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 952952DNA topoisomerase 1 HAMAP-Rule MF_00952
PRO_0000145166

Regions

Domain12 – 135124Toprim
Region184 – 1896Interaction with DNA By similarity

Sites

Active site3341O-(5'-phospho-DNA)-tyrosine intermediate By similarity
Metal binding181Magnesium 1; catalytic By similarity
Metal binding1041Magnesium 1; catalytic By similarity
Metal binding1041Magnesium 2 By similarity
Metal binding1061Magnesium 2 By similarity
Site421Interaction with DNA By similarity
Site1601Interaction with DNA By similarity
Site1611Interaction with DNA By similarity
Site1641Interaction with DNA By similarity
Site1691Interaction with DNA By similarity
Site1761Interaction with DNA By similarity
Site3361Interaction with DNA By similarity
Site5341Interaction with DNA By similarity

Sequences

Sequence LengthMass (Da)Tools
Q9X909 [UniParc].

Last modified November 1, 1999. Version 1.
Checksum: 1C98DABD7A629295

FASTA952103,585
        10         20         30         40         50         60 
MSPTSETAKG GRRLVIVESP AKAKTIKGYL GPGYVVEASV GHIRDLPSGA AEVPEKYTGE 

        70         80         90        100        110        120 
VRRLGVDVEH DFQPIYVVNA DKKSQVKKLK DLLKESDELF LATDEDREGE AIAWHLQEVL 

       130        140        150        160        170        180 
KPKIPVKRMV FHEITKDAIR AAVANPRELN QKLVDAQETR RILDRLYGYE VSPVLWKKVM 

       190        200        210        220        230        240 
PRLSAGRVQS VATRLVVERE RERIAFRSAE YWDLTGTFAT GRAGDASDPS SLVARLQTVD 

       250        260        270        280        290        300 
GRRVAQGRDF DSLGQLKSAN TLHLDEANAR ALAAALENTR FAVRSVESKP YRRSPYAPFR 

       310        320        330        340        350        360 
TTTLQQEASR KLGFGAKSTM QVAQKLYENG YITYMRTDST TLSDTAVSAA RAQVTQLYGA 

       370        380        390        400        410        420 
DYLPPQPRTY AGKVKNAQEA HEAIRPSGDR FRTPAETGLT GDQFKLYELI WKRTVASQMK 

       430        440        450        460        470        480 
DATGNSVTVK IGGAASDGRD VEFSASGKTI TFHGFLKAYV EGADDPNAEL DDRERRLPQV 

       490        500        510        520        530        540 
AEGDALTAEE ITVDGHATKP PARYTEASLV KELEEREIGR PSTYASIIGT ILDRGYVFKK 

       550        560        570        580        590        600 
GTALVPSFLS FAVVNLLEKH FGRLVDYDFT ARMEDDLDRI ARGEAQSVPW LRRFYFGEGD 

       610        620        630        640        650        660 
GTGGGGAADA GNGDGDHLGG LKELVTDLGA IDAREVSSFP VGNDIKLRVG RYGPYVERGE 

       670        680        690        700        710        720 
KDAENHQRAD VPEDLAPDEL SVELAEELLA KPSGDFELGT DPATGHAIVA KDGRYGPYVT 

       730        740        750        760        770        780 
EVLPEGTPKT GKNAVKPRTA SLFKSMSLDT VTLDDALKLM SLPRVVGADA EGVEITAQNG 

       790        800        810        820        830        840 
RYGPYLKKGT DSRSLQTEDQ LFEITLEEAL AIYAQPKQRG RAAAKPPLKE LGTDPVSEKP 

       850        860        870        880        890        900 
VVVKDGRFGP YVTDGETNAT LRSDDSVEEI TPERGYELLA EKRAKGPAKK TAKKAVKKTA 

       910        920        930        940        950 
AKKAPAKKAA ATKKTAAAKT TAAKKTAAKS TAKKTTAKTA AKKATASKTS ED 

« Hide

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AL939116 Genomic DNA. Translation: CAB38480.1.
PIRT36664.
RefSeqNP_627741.1. NC_003888.3.

3D structure databases

ProteinModelPortalQ9X909.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING100226.SCO3543.

Proteomic databases

PRIDEQ9X909.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaCAB38480; CAB38480; CAB38480.
GeneID1098979.
KEGGsco:SCO3543.
PATRIC23736830. VBIStrCoe124346_3599.

Phylogenomic databases

eggNOGCOG1754.
HOGENOMHOG000004020.
KOK03168.
OMAFRSAEYW.
OrthoDBEOG6S7XQ9.
PhylomeDBQ9X909.

Family and domain databases

Gene3D1.10.460.10. 2 hits.
2.70.20.10. 2 hits.
3.40.50.140. 1 hit.
HAMAPMF_00952. Topoisom_1_prok.
InterProIPR000380. Topo_IA.
IPR003601. Topo_IA_2.
IPR023406. Topo_IA_AS.
IPR013497. Topo_IA_cen.
IPR013824. Topo_IA_cen_sub1.
IPR013825. Topo_IA_cen_sub2.
IPR023405. Topo_IA_core_domain.
IPR003602. Topo_IA_DNA-bd.
IPR005733. TopoI_bac-type.
IPR028612. Topoisom_1_IA.
IPR025589. Toprim_C_rpt.
IPR006171. Toprim_domain.
[Graphical view]
PANTHERPTHR11390. PTHR11390. 1 hit.
PfamPF01131. Topoisom_bac. 1 hit.
PF01751. Toprim. 1 hit.
PF13368. Toprim_C_rpt. 4 hits.
[Graphical view]
PRINTSPR00417. PRTPISMRASEI.
SMARTSM00437. TOP1Ac. 1 hit.
SM00436. TOP1Bc. 1 hit.
SM00493. TOPRIM. 1 hit.
[Graphical view]
SUPFAMSSF56712. SSF56712. 1 hit.
TIGRFAMsTIGR01051. topA_bact. 1 hit.
PROSITEPS00396. TOPOISOMERASE_I_PROK. 1 hit.
PS50880. TOPRIM. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameTOP1_STRCO
AccessionPrimary (citable) accession number: Q9X909
Entry history
Integrated into UniProtKB/Swiss-Prot: May 30, 2000
Last sequence update: November 1, 1999
Last modified: July 9, 2014
This is version 98 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families