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

Q9KRB2 (TOP1_VIBCH) Reviewed, UniProtKB/Swiss-Prot

Last modified April 16, 2014. Version 101. 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:VC_1730
OrganismVibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961) [Reference proteome] [HAMAP]
Taxonomic identifier243277 [NCBI]
Taxonomic lineageBacteriaProteobacteriaGammaproteobacteriaVibrionalesVibrionaceaeVibrio

Protein attributes

Sequence length876 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.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 876876DNA topoisomerase 1 HAMAP-Rule MF_00952
PRO_0000145171

Regions

Domain3 – 150148Toprim
Zinc finger668 – 69528C4-type 1 HAMAP-Rule MF_00952
Zinc finger717 – 74226C4-type 2 HAMAP-Rule MF_00952
Region200 – 2056Interaction with DNA By similarity

Sites

Active site3271O-(5'-phospho-DNA)-tyrosine intermediate By similarity
Metal binding91Magnesium 1; catalytic By similarity
Metal binding1191Magnesium 1; catalytic By similarity
Metal binding1191Magnesium 2 By similarity
Metal binding1211Magnesium 2 By similarity
Site331Interaction with DNA By similarity
Site1761Interaction with DNA By similarity
Site1771Interaction with DNA By similarity
Site1801Interaction with DNA By similarity
Site1921Interaction with DNA By similarity
Site3291Interaction with DNA By similarity
Site5141Interaction with DNA By similarity

Sequences

Sequence LengthMass (Da)Tools
Q9KRB2 [UniParc].

Last modified October 1, 2000. Version 1.
Checksum: 8A5BC9148CA1B753

FASTA87697,910
        10         20         30         40         50         60 
MGKSLVIVES PAKAKTINKY LGKDFIVKSS VGHVRDLPTA GQTATPTGKA AAASTKKAST 

        70         80         90        100        110        120 
TDKEQQKREK ERAALIKKMG VDPYHGWQAN YQILPGKEKV VAELQKLAKD ADSVYLATDL 

       130        140        150        160        170        180 
DREGEAIAWH LREIIGGDEK RYKRVVFNEI TKNAIQQAFK QPGELNMDGV NAQQARRFMD 

       190        200        210        220        230        240 
RVVGFMVSPL LWKKVARGLS AGRVQSVAVK LLVEREREIK AFVPEEFWDI NADTLTADKQ 

       250        260        270        280        290        300 
DFRLLVAQKD GLAFKPVNET EALAAVAALN KAQYEVCKRE DKPTTSKPSA PFITSTLQQA 

       310        320        330        340        350        360 
ASTRLGYGVK KTMMLAQRLY EAGYITYMRT DSTNLSAEAV ENLRGYITKH YGEAYLPSQP 

       370        380        390        400        410        420 
NVYGSKQNAQ EAHEAIRPSD VTVTADDLEG MEADAHKLYA LIWNQFVACQ MTPAQYDSTT 

       430        440        450        460        470        480 
VSVKAAEYTL KAKGRILKFD GWTRVQRPLG KNEDQILPPV KVGDSLKLVS LDPKQHFTKP 

       490        500        510        520        530        540 
PARYTEAALV KELEKRGIGR PSTYASIIST IQDRGYVKVD QRRFFAEKMG EIVTDRLDEN 

       550        560        570        580        590        600 
FDDLMNYDFT ARMEEKLDQI AEGEVNWTAV LDEFFADFSR DLETAEQDES LGGMKPNHIV 

       610        620        630        640        650        660 
MTNILCPTCS RPMGIRTAST GVFLGCSGYG LPPKERCKTT INLGDEEGVI NVLEEDVETA 

       670        680        690        700        710        720 
ALRAKKRCPI CETAMDAYLI DDKRKLHVCG NNPNCEGFIV EEGEFKVKGY EGPTVECDKC 

       730        740        750        760        770        780 
GSDMVLKNGR FGKYMGCTND ACKNTRKILK NGEVAPPKEE PVHFPELPCE NSDAYFVLRD 

       790        800        810        820        830        840 
GASGLFFAAS NFPKSRETRA PLVEELKRFA ERLPEKYQYL TSAPAHDPDG LPAVVRFSRK 

       850        860        870 
EKEHYVRTET EGKPSGWMAV YQEGKWLVTD KRKNAK 

« Hide

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AE003852 Genomic DNA. Translation: AAF94880.1.
PIRB82163.
RefSeqNP_231366.1. NC_002505.1.

3D structure databases

ProteinModelPortalQ9KRB2.
SMRQ9KRB2. Positions 2-579, 751-867.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING243277.VC1730.

Protocols and materials databases

DNASU2613735.
StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblBacteriaAAF94880; AAF94880; VC_1730.
GeneID2613735.
KEGGvch:VC1730.
PATRIC20082518. VBIVibCho83274_1655.

Phylogenomic databases

eggNOGCOG0551.
KOK03168.
OMAMVYKMGR.
OrthoDBEOG6S7XQ9.
ProtClustDBPRK07561.

Enzyme and pathway databases

BioCycVCHO:VC1730-MONOMER.

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.
IPR013498. Topo_IA_Znf.
IPR005733. TopoI_bac-type.
IPR013263. TopoI_Znr_bac.
IPR028612. Topoisom_1_IA.
IPR006171. Toprim_domain.
[Graphical view]
PANTHERPTHR11390. PTHR11390. 1 hit.
PfamPF08272. Topo_Zn_Ribbon. 2 hits.
PF01131. Topoisom_bac. 1 hit.
PF01751. Toprim. 1 hit.
PF01396. zf-C4_Topoisom. 1 hit.
[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_VIBCH
AccessionPrimary (citable) accession number: Q9KRB2
Entry history
Integrated into UniProtKB/Swiss-Prot: December 1, 2000
Last sequence update: October 1, 2000
Last modified: April 16, 2014
This is version 101 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