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P32989 (TOP1_VAR67) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 85. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | 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
Gene names
Name:TOP1
ORF Names:H6R, I6R
OrganismVariola virus (isolate Human/India/Ind3/1967) (VARV) (Smallpox virus) [Reference proteome]
Taxonomic identifier587200 [NCBI]
Taxonomic lineageVirusesdsDNA viruses, no RNA stagePoxviridaeChordopoxvirinaeOrthopoxvirus
Virus hostHomo sapiens (Human) [TaxID: 9606]

Protein attributes

Sequence length314 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

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.

Catalytic activity

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

Induction

Expressed in the late phase of the viral replicative cycle.

Sequence similarities

Belongs to the type IB topoisomerase family.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 314314DNA topoisomerase 1
PRO_0000145217

Sites

Active site2741O-(3'-phospho-DNA)-tyrosine intermediate
Site1681Involved in religation Probable

Experimental info

Mutagenesis1681D → A: Increased DNA-binding affinity, inhibition of product release, defective in relaxation of supercoiled plasmid substrates. Ref.4

Secondary structure

................................................... 314
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P32989 [UniParc].

Last modified October 1, 1993. Version 1.
Checksum: AE9C7DC5FA363BEE

FASTA31436,592
        10         20         30         40         50         60 
MRALFYKDGK LFTDNNFLNP VSDNNPAYEV LQHVKIPTHL TDVVVYGQTW EEALTRLIFV 

        70         80         90        100        110        120 
GSDSKGRRQY FYGKMHVQNR NAKRDRIFVR VYNVMKRINC FINKNIKKSS TDSNYQLAVF 

       130        140        150        160        170        180 
MLMETMFFIR FGKMKYLKEN ETVGLLTLKN KHIEISPDKI VIKFVGKDKV SHEFVVHKSN 

       190        200        210        220        230        240 
RLYKPLLKLT DDSSPEEFLF NKLSERKVYE CIKQFGIRIK DLRTYGVNYT FLYNFWTNVK 

       250        260        270        280        290        300 
SISPLPSPKK LIALTIKQTA EVVGHTPSIS KRAYMATTIL EMVKDKNFLD VVSKTTFDEF 

       310 
LSIVVDHVKS STDG 

« Hide

References

« Hide 'large scale' references
[1]"Nucleotide sequence analysis of variola virus HindIII M, L, I genome fragments."
Shchelkunov S.N., Blinov V.M., Totmenin A.V., Marennikova S.S., Kolykhalov A.A., Frolov I.V., Chizhikov V.E., Gytorov V.V., Gashikov P.V., Belanov E.F., Belavin P.A., Resenchuk S.M., Andzhaparidze O.G., Sandakhchiev L.S.
Virus Res. 27:25-35(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[2]"Genes of variola and vaccinia viruses necessary to overcome the host protective mechanisms."
Shchelkunov S.N., Blinov V.M., Sandakhchiev L.S.
FEBS Lett. 319:80-83(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[3]"Variola virus topoisomerase: DNA cleavage specificity and distribution of sites in Poxvirus genomes."
Minkah N., Hwang Y., Perry K., Van Duyne G.D., Hendrickson R., Lefkowitz E.J., Hannenhalli S., Bushman F.D.
Virology 365:60-69(2007) [PubMed] [Europe PMC] [Abstract]
Cited for: CHARACTERIZATION.
[4]"Structural basis for specificity in the poxvirus topoisomerase."
Perry K., Hwang Y., Bushman F.D., Van Duyne G.D.
Mol. Cell 23:343-354(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS), MUTAGENESIS OF ASP-168.
[5]"Insights from the structure of a smallpox virus topoisomerase-DNA transition state mimic."
Perry K., Hwang Y., Bushman F.D., Van Duyne G.D.
Structure 18:127-137(2010) [PubMed] [Europe PMC] [Abstract]
Cited for: X-RAY CRYSTALLOGRAPHY (2.1 ANGSTROMS).

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
X67119 Genomic DNA. Translation: CAA47588.1.
S55844 Genomic DNA. Translation: AAB24685.1.
X69198 Genomic DNA. Translation: CAA49030.1.
PIRE36846.
RefSeqNP_042133.1. NC_001611.1.

3D structure databases

PDBe
RCSB-PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
2H7FX-ray2.70X1-314[»]
2H7GX-ray1.90X1-314[»]
3IGCX-ray2.10A1-314[»]
ProteinModelPortalP32989.
SMRP32989. Positions 1-314.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

GeneID1486444.

Family and domain databases

Gene3D1.20.120.380. 1 hit.
3.30.66.10. 1 hit.
3.90.15.10. 1 hit.
InterProIPR011010. 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]
PfamPF01028. Topoisom_I. 1 hit.
PF09266. VirDNA-topo-I_N. 1 hit.
[Graphical view]
PRINTSPR00416. EUTPISMRASEI.
SUPFAMSSF56349. SSF56349. 1 hit.
PROSITEPS00176. TOPOISOMERASE_I_EUK. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceP32989.

Entry information

Entry nameTOP1_VAR67
AccessionPrimary (citable) accession number: P32989
Entry history
Integrated into UniProtKB/Swiss-Prot: October 1, 1993
Last sequence update: October 1, 1993
Last modified: July 9, 2014
This is version 85 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references