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Human DNA Topoisomerase I (70 Kda) In Non-Covalent Complex With A 22 Base Pair DNA Duplex Containing an 8-oxoG Lesion

Source organism: Homo sapiens
Biochemical function: DNA topoisomerase type I (single strand cut, ATP-independent) activity
Biological process: DNA topological change
Cellular component: chromosome

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EC 5.6.2.1: DNA topoisomerase

Reaction catalysed:
ATP-independent breakage of single-stranded DNA, followed by passage and rejoining
Systematic name:
DNA topoisomerase
Alternative Name(s):
  • DNA topoisomerase I
  • Nicking-closing enzyme
  • Omega-protein
  • Relaxing enzyme
  • Swivelase
  • Type I DNA topoisomerase
  • Untwisting enzyme

GO terms

Sequence families

Pfam Protein families (Pfam)
PF14370
Domain description: C-terminal topoisomerase domain
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of Pfam domain PF14370 (C-terminal topoisomerase domain) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].

PF01028
Domain description: Eukaryotic DNA topoisomerase I, catalytic core
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of Pfam domain PF01028 (Eukaryotic DNA topoisomerase I, catalytic core) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].

PF02919
Domain description: Eukaryotic DNA topoisomerase I, DNA binding fragment
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of Pfam domain PF02919 (Eukaryotic DNA topoisomerase I, DNA binding fragment) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].

InterPro InterPro annotations
IPR001631
Domain description: DNA topoisomerase I
Occurring in:
  1. DNA topoisomerase 1
IPR013500
Domain description: DNA topoisomerase I, catalytic core, eukaryotic-type
Occurring in:
  1. DNA topoisomerase 1
IPR025834
Domain description: Topoisomerase I C-terminal domain
Occurring in:
  1. DNA topoisomerase 1
IPR014727
Domain description: DNA topoisomerase I, catalytic core, alpha/beta subdomain
Occurring in:
  1. DNA topoisomerase 1
IPR014711
Domain description: DNA topoisomerase I, catalytic core, alpha-helical subdomain, eukaryotic-type
Occurring in:
  1. DNA topoisomerase 1
IPR011010
Domain description: DNA breaking-rejoining enzyme, catalytic core
Occurring in:
  1. DNA topoisomerase 1
IPR013499
Domain description: DNA topoisomerase I, eukaryotic-type
Occurring in:
  1. DNA topoisomerase 1
IPR013034
Domain description: DNA topoisomerase I, DNA binding, N-terminal domain 1
Occurring in:
  1. DNA topoisomerase 1
IPR048045
Domain description: DNA topoisomerase I, DNA-binding domain
Occurring in:
  1. DNA topoisomerase 1
IPR008336
Domain description: DNA topoisomerase I, DNA binding, eukaryotic-type
Occurring in:
  1. DNA topoisomerase 1
IPR013030
Domain description: DNA topoisomerase I, DNA binding, N-terminal domain 2
Occurring in:
  1. DNA topoisomerase 1
IPR036202
Domain description: DNA topoisomerase I, DNA binding, eukaryotic-type, N-terminal domain superfamily
Occurring in:
  1. DNA topoisomerase 1

Structure domains

CATH CATH domains
2.170.11.10
Class: Mainly Beta
Architecture: Beta Complex
Topology: DNA Topoisomerase I; domain 2
Homology: DNA Topoisomerase I, domain 2
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of CATH domain 2.170.11.10 (DNA Topoisomerase I; domain 2) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
1.10.132.10
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Topoisomerase I; Chain A, domain 4
Homology: Topoisomerase I; Chain A, domain 4
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of CATH domain 1.10.132.10 (Topoisomerase I; Chain A, domain 4) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
3.90.15.10
Class: Alpha Beta
Architecture: Alpha-Beta Complex
Topology: Topoisomerase I; Chain A, domain 3
Homology: Topoisomerase I; Chain A, domain 3
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of CATH domain 3.90.15.10 (Topoisomerase I; Chain A, domain 3) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
1.10.10.41
Class: Mainly Alpha
Architecture: Orthogonal Bundle
Topology: Arc Repressor Mutant, subunit A
Homology: Yeast DNA topoisomerase - domain 1
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of CATH domain 1.10.10.41 (Arc Repressor Mutant, subunit A) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
SCOP SCOP annotations
56361
Class: Alpha and beta proteins (a+b)
Fold: DNA breaking-rejoining enzymes
Superfamily: DNA breaking-rejoining enzymes
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of SCOP domain 56361 (Eukaryotic DNA topoisomerase I, catalytic core) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
46597
Class: All alpha proteins
Fold: Long alpha-hairpin
Superfamily: Eukaryotic DNA topoisomerase I, dispensable insert domain
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of SCOP domain 46597 (Eukaryotic DNA topoisomerase I, dispensable insert domain) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].
56742
Class: Multi-domain proteins (alpha and beta)
Fold: Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment
Superfamily: Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment
Occurring in:
  1. DNA topoisomerase 1
The deposited structure of PDB entry 1lpq contains 1 copy of SCOP domain 56742 (Eukaryotic DNA topoisomerase I, N-terminal DNA-binding fragment) in DNA topoisomerase 1. Showing 1 copy in chain C [auth A].

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