Q76ZS7 (TOP1_VACCA) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
DNA topoisomerase 1B
Short name=TopIB
EC=5.99.1.2

Alternative name(s):
DNA topoisomerase I
Late protein H6

Gene names

Name:	TOP1
Ordered Locus Names:	MVA096R, ACAM3000_MVA_096

Organism

Vaccinia virus (strain Ankara) (VACV)

Taxonomic identifier

126794 [NCBI]

Taxonomic lineage

Viruses › dsDNA viruses, no RNA stage › Poxviridae › Chordopoxvirinae › Orthopoxvirus › Vaccinia virus

Virus host

Homo sapiens (Human) [TaxID: 9606]

Protein attributes

Sequence length	314 AA.
Sequence status	Complete.
Protein existence	Evidence at transcript 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 than 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.

Ontologies

Keywords
Developmental stage	Late protein
Ligand	ATP-binding DNA-binding Nucleotide-binding
Molecular function	Isomerase Topoisomerase
Gene Ontology (GO)
Biological process	DNA topological change Inferred from electronic annotation. Source: InterPro
Cellular component	chromosome Inferred from electronic annotation. Source: InterPro
Molecular function	ATP binding Inferred from electronic annotation. Source: UniProtKB-KW DNA topoisomerase (ATP-hydrolyzing) activity Inferred from electronic annotation. Source: InterPro DNA topoisomerase type I activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 314	314	DNA topoisomerase 1B		PRO_0000145214
Sites
	Active site	274	1	O-(3'-phospho-DNA)-tyrosine intermediate By similarity
	Site	168	1	Involved in religation By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q76ZS7 [UniParc]. Last modified July 5, 2004. Version 1. Checksum: E76FBCFCBF259D27	FASTA	314	36,666
	10 20 30 40 50 60 MRALFYKDGK LFTDNNFLNP VSDDNPAYEV LQHVKIPTHL TDVVVYEQTW EEALTRLIFV 70 80 90 100 110 120 GSDSKGRRQY FYGKMHVQNR NAKRDRIFVR VYNVMKRINC FINKNIKKSS TDSNYQLAVF 130 140 150 160 170 180 MLMETMFFIR FGKMKYLKEN ETVGLLTLKN KHIEISPDEI 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

References

[1]	"The complete genomic sequence of the modified vaccinia Ankara strain: comparison with other orthopoxviruses." Antoine G., Scheiflinger F., Dorner F., Falkner F.G. Virology 244:365-396(1998) [PubMed: 9601507] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
[2]	Esposito J.J., Frace M., Sammons S.A., Olsen-Rasmussen M.S., Osborne J., Khristova M., Wohlhueter R.M. Submitted (APR-2004) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: Isolate Acambis 3000.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	U94848 Genomic DNA. Translation: AAB96509.1. AY603355 Genomic DNA. Translation: AAT10494.1.
RefSeq	YP_232986.1. NC_006998.1.
3D structure databases
ProteinModelPortal	Q76ZS7.
SMR	Q76ZS7. Positions 1-314.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Genome annotation databases
GeneID	3707560.
Phylogenomic databases
ProtClustDB	PHA3101.
Family and domain databases
InterPro	IPR011010. DNA_brk_join_enz. IPR018521. TopoI_AS. IPR001631. TopoI_C. IPR014711. TopoI_cat_a-hlx-sub_euk. IPR013500. TopoI_cat_euk. IPR015346. TopoI_N_vir. [Graphical view]
Gene3D	G3DSA:3.30.66.10. G3DSA:3.30.66.10. 1 hit. G3DSA:3.90.15.10. TopoI_cat_a-hlx-sub_euk. 1 hit.
Pfam	PF01028. Topoisom_I. 1 hit. PF09266. VirDNA-topo-I_N. 1 hit. [Graphical view]
PRINTS	PR00416. EUTPISMRASEI.
SUPFAM	SSF56349. DNA_brk_join_enz. 1 hit.
PROSITE	PS00176. TOPOISOMERASE_I_EUK. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

TOP1_VACCA

Accession

Primary (citable) accession number: Q76ZS7

Entry history

Integrated into UniProtKB/Swiss-Prot:	December 7, 2004
Last sequence update:	July 5, 2004
Last modified:	November 16, 2011
This is version 41 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program