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Protein

DNA topoisomerase 1

Gene

TOP1

Organism
Variola virus (isolate Human/India/Ind3/1967) (VARV) (Smallpox virus)
Status
Reviewed-Annotation score: Annotation score: 3 out of 5-Experimental evidence at protein leveli

Functioni

Releases the supercoiling and torsional tension of DNA 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 the specific target site 5'-[CT]CCTTp site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA-(3'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 5'-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 5'-OH attacks the covalent intermediate to expel the active-site tyrosine and restore the DNA phosphodiester backbone (By similarity).By similarity

Catalytic activityi

ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.PROSITE-ProRule annotation

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sitei168Involved in religation1 Publication1
Active sitei274O-(3'-phospho-DNA)-tyrosine intermediate1 Publication1

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Isomerase, Topoisomerase

Keywords - Ligandi

DNA-binding

Names & Taxonomyi

Protein namesi
Recommended name:
DNA topoisomerase 1 (EC:5.99.1.2)
Alternative name(s):
DNA topoisomerase I
Gene namesi
Name:TOP1
ORF Names:H6R, I6R
OrganismiVariola virus (isolate Human/India/Ind3/1967) (VARV) (Smallpox virus)
Taxonomic identifieri587200 [NCBI]
Taxonomic lineageiVirusesdsDNA viruses, no RNA stagePoxviridaeChordopoxvirinaeOrthopoxvirus
Virus hostiHomo sapiens (Human) [TaxID: 9606]
Proteomesi
  • UP000002060 Componenti: Genome

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi168D → A: Increased DNA-binding affinity, inhibition of product release, defective in relaxation of supercoiled plasmid substrates. 1 Publication1

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00001452171 – 314DNA topoisomerase 1Add BLAST314

Expressioni

Inductioni

Expressed in the late phase of the viral replicative cycle.

Keywords - Developmental stagei

Late protein

Structurei

Secondary structure

1314
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi3 – 7Combined sources5
Beta strandi10 – 14Combined sources5
Helixi27 – 33Combined sources7
Beta strandi41 – 48Combined sources8
Helixi50 – 53Combined sources4
Beta strandi56 – 62Combined sources7
Beta strandi68 – 72Combined sources5
Helixi74 – 105Combined sources32
Helixi113 – 127Combined sources15
Helixi134 – 140Combined sources7
Helixi150 – 152Combined sources3
Beta strandi153 – 156Combined sources4
Beta strandi159 – 165Combined sources7
Helixi167 – 169Combined sources3
Beta strandi171 – 177Combined sources7
Helixi183 – 189Combined sources7
Beta strandi197 – 200Combined sources4
Helixi205 – 212Combined sources8
Helixi213 – 215Combined sources3
Helixi219 – 241Combined sources23
Beta strandi242 – 244Combined sources3
Helixi248 – 263Combined sources16
Turni267 – 269Combined sources3
Helixi270 – 273Combined sources4
Helixi276 – 282Combined sources7
Helixi288 – 293Combined sources6
Helixi297 – 311Combined sources15

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2H7FX-ray2.70X1-314[»]
2H7GX-ray1.90X1-314[»]
3IGCX-ray2.10A1-314[»]
ProteinModelPortaliP32989.
SMRiP32989.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP32989.

Family & Domainsi

Sequence similaritiesi

Belongs to the type IB topoisomerase family.Curated

Phylogenomic databases

KOiK03168.

Family and domain databases

CDDicd00659. Topo_IB_C. 1 hit.
Gene3Di1.20.120.380. 1 hit.
3.30.66.10. 1 hit.
3.90.15.10. 1 hit.
InterProiIPR011010. DNA_brk_join_enz.
IPR001631. TopoI.
IPR018521. TopoI_AS.
IPR014711. TopoI_cat_a-hlx-sub_euk.
IPR027362. TopoI_cat_dom2.
IPR013500. TopoI_cat_euk.
IPR015346. TopoI_N_vir.
[Graphical view]
PfamiPF01028. Topoisom_I. 1 hit.
PF09266. VirDNA-topo-I_N. 1 hit.
[Graphical view]
PRINTSiPR00416. EUTPISMRASEI.
SUPFAMiSSF56349. SSF56349. 1 hit.
PROSITEiPS00176. TOPOISOMERASE_I_EUK. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P32989-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MRALFYKDGK LFTDNNFLNP VSDNNPAYEV LQHVKIPTHL TDVVVYGQTW
60 70 80 90 100
EEALTRLIFV GSDSKGRRQY FYGKMHVQNR NAKRDRIFVR VYNVMKRINC
110 120 130 140 150
FINKNIKKSS TDSNYQLAVF MLMETMFFIR FGKMKYLKEN ETVGLLTLKN
160 170 180 190 200
KHIEISPDKI VIKFVGKDKV SHEFVVHKSN RLYKPLLKLT DDSSPEEFLF
210 220 230 240 250
NKLSERKVYE CIKQFGIRIK DLRTYGVNYT FLYNFWTNVK SISPLPSPKK
260 270 280 290 300
LIALTIKQTA EVVGHTPSIS KRAYMATTIL EMVKDKNFLD VVSKTTFDEF
310
LSIVVDHVKS STDG
Length:314
Mass (Da):36,592
Last modified:October 1, 1993 - v1
Checksum:iAE9C7DC5FA363BEE
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X67119 Genomic DNA. Translation: CAA47588.1.
S55844 Genomic DNA. Translation: AAB24685.1.
X69198 Genomic DNA. Translation: CAA49030.1.
PIRiE36846.
RefSeqiNP_042133.1. NC_001611.1.

Genome annotation databases

GeneIDi1486444.
KEGGivg:1486444.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
X67119 Genomic DNA. Translation: CAA47588.1.
S55844 Genomic DNA. Translation: AAB24685.1.
X69198 Genomic DNA. Translation: CAA49030.1.
PIRiE36846.
RefSeqiNP_042133.1. NC_001611.1.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
2H7FX-ray2.70X1-314[»]
2H7GX-ray1.90X1-314[»]
3IGCX-ray2.10A1-314[»]
ProteinModelPortaliP32989.
SMRiP32989.
ModBaseiSearch...
MobiDBiSearch...

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

GeneIDi1486444.
KEGGivg:1486444.

Phylogenomic databases

KOiK03168.

Miscellaneous databases

EvolutionaryTraceiP32989.

Family and domain databases

CDDicd00659. Topo_IB_C. 1 hit.
Gene3Di1.20.120.380. 1 hit.
3.30.66.10. 1 hit.
3.90.15.10. 1 hit.
InterProiIPR011010. DNA_brk_join_enz.
IPR001631. TopoI.
IPR018521. TopoI_AS.
IPR014711. TopoI_cat_a-hlx-sub_euk.
IPR027362. TopoI_cat_dom2.
IPR013500. TopoI_cat_euk.
IPR015346. TopoI_N_vir.
[Graphical view]
PfamiPF01028. Topoisom_I. 1 hit.
PF09266. VirDNA-topo-I_N. 1 hit.
[Graphical view]
PRINTSiPR00416. EUTPISMRASEI.
SUPFAMiSSF56349. SSF56349. 1 hit.
PROSITEiPS00176. TOPOISOMERASE_I_EUK. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiTOP1_VAR67
AccessioniPrimary (citable) accession number: P32989
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 1, 1993
Last sequence update: October 1, 1993
Last modified: November 30, 2016
This is version 95 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.