Q7V2N7 · Q7V2N7_PROMP

Function

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.

Catalytic activity

  • ATP-independent breakage of single-stranded DNA, followed by passage and rejoining.
    EC:5.6.2.1 (UniProtKB | ENZYME | Rhea)

Features

Showing features for site, active site.

1870100200300400500600700800
Type
IDPosition(s)Description
Site33Interaction with DNA
Site152Interaction with DNA
Site153Interaction with DNA
Site156Interaction with DNA
Site161Interaction with DNA
Site168Interaction with DNA
Active site321O-(5'-phospho-DNA)-tyrosine intermediate
Site323Interaction with DNA
Site516Interaction with DNA

GO annotations

AspectTerm
Molecular FunctionDNA binding
Molecular FunctionDNA topoisomerase type I (single strand cut, ATP-independent) activity
Molecular Functionmetal ion binding
Biological ProcessDNA topological change

Keywords

Enzyme and pathway databases

Names & Taxonomy

Protein names

  • Recommended name
    DNA topoisomerase 1
  • EC number
  • Alternative names
    • DNA topoisomerase I

Gene names

    • Name
      topA
    • Ordered locus names
      PMM0436

Organism names

Accessions

  • Primary accession
    Q7V2N7

Proteomes

Interaction

Subunit

Monomer.

Protein-protein interaction databases

Family & Domains

Features

Showing features for domain, region.

Type
IDPosition(s)Description
Domain3-127Toprim
Region176-181Interaction with DNA
Region361-383Disordered

Sequence similarities

Belongs to the type IA topoisomerase family.

Phylogenomic databases

Family and domain databases

Sequence

  • Sequence status
    Complete
  • Length
    870
  • Mass (Da)
    97,830
  • Last updated
    2003-10-01 v1
  • MD5 Checksum
    E8F47816A5D09C79390F36D65097F263
MDHTLVIVESPTKAKTIRRFLPPNYEVLASMGHVRDLPKGAAEIPASVKKEKWSRIGVNTTEDFEPLYIVPKEKKKVVKDLKNALKDATQLLLATDEDREGESISWHLMQILKPKIPTKRMVFHEITKKAINKALDETREIDMELVQAQETRRILDRLFGYELSPLLWKKVAPRLSAGRVQSVSVRLLVNKERERRAFKKASYWGLKATLLKDNISFESKLFSLNAQKISNGSDFDEKTGNLKKGNKSLILNEDRAKSLLKTLSKEKWKVLRVEKKPTIRKPVPPFTTSTLQQEANRKLRLSARETMRCAQGLYEKGFITYMRTDSVHLSEQAIRAARECVNSKYGKEYLSSSARQFNSNARNAQEAHEAIRPAGEVFKTPNDTDLSGRDLSLYELIWKRTVASQMAEAKLTMINAEIEVGEGLFKSSGKSIDFAGFFRAYVEGSDDPSASLEQQEVILPDLTQGSVLEVDSKEATYHETKSPARYTEAALVKVLEKEGIGRPSTYASIIGTIVDRGYANISSNSLSPTFTAFAVTALLEEHFPDLVDTTFTAKMESSLDEISSGNLEWLPYLETFYKGKNGLEVKVQKTEGDIDGKAYRQVDFDDLPCVVRIGSNGPWLEGVKIDESGNEIQAKGNLPMDITPGDLDKKKVDQILSGPSDLGTDPKTGEQVFLRFGPYGPYVQLGNTEEDKAKPRRASLPKELKTDDLTLLEALELLSLPKLLGEHPEGGIVEADRGRFGPYIKWIKNEDESENRSLKKEDDVFKVDLKRALEILAMPKLGRGGQEVIKDFGKPKELKDKIQILNGRYGLYIKCGKTNVSLPKDTDLEKFTLDNALVLLEEKMKDKNSSVFKKNKVISKKTLKNKKSKK

Sequence databases

Nucleotide SequenceProtein SequenceMolecule TypeStatus
BX548174
EMBL· GenBank· DDBJ
CAE18895.1
EMBL· GenBank· DDBJ
Genomic DNA

Genome annotation databases

Similar Proteins

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