DNA topoisomerase IV complex

GO:0009340 · Other · Multiprotein complex · Proposed

A bacterial type IIA topoisomerase complex composed of ParC and ParE subunits that can relax supercoiled DNA and supports chromosome segregation. [GO:0009340]

Synonyms: topoisomerase IV

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
DNA topoisomerase IV subunit A	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	parC			ParC subunit class that, together with the ParE subunit class, forms bacterial DNA topoisomerase IV. `GO:0009340` GO:0009340 defines DNA topoisomerase IV as containing ParC and ParE. `PMID:8227000` Peng and Marians 1993 purified and characterized the E. coli topoisomerase IV subunits and their interactions. `UniProtKB:P0AFI2` UniProtKB P0AFI2 is the reviewed Escherichia coli K-12 ParC entry and cross-references GO:0009330 with experimental evidence.
DNA topoisomerase IV subunit B	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	parE			ParE subunit class that, together with the ParC subunit class, forms bacterial DNA topoisomerase IV. `GO:0009340` GO:0009340 defines DNA topoisomerase IV as containing ParC and ParE. `PMID:8227000` Peng and Marians 1993 purified and characterized the E. coli topoisomerase IV subunits and their interactions. `UniProtKB:P20083` UniProtKB P20083 is the reviewed Escherichia coli K-12 ParE entry for DNA topoisomerase 4 subunit B.

Organism-specific protein examples

Named proteins in which each component's role was established, with the organism the evidence comes from. The component above is the taxon-agnostic family; these are the specific entries behind it.

DNA topoisomerase IV subunit A

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P0AFI2`	DNA topoisomerase 4 subunit A	parC	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (1 reference) Reviewed E. coli K-12 ParC accession for topoisomerase IV subunit A. `UniProtKB:P0AFI2` UniProtKB P0AFI2 is the reviewed Escherichia coli K-12 entry for gene parC, DNA topoisomerase 4 subunit A.

DNA topoisomerase IV subunit B

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P20083`	DNA topoisomerase 4 subunit B	parE	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (1 reference) Reviewed E. coli K-12 ParE accession for topoisomerase IV subunit B. `UniProtKB:P20083` UniProtKB P20083 is the reviewed Escherichia coli K-12 entry for gene parE, DNA topoisomerase 4 subunit B.

Canonical examples

NCBITaxon:562 Escherichia coli — Source species in the original purification and subunit-interaction study of bacterial DNA topoisomerase IV. [PMID:8227000]

Functions

DNA topoisomerase type II activity GO:0003918 — DNA topoisomerase IV performs ATP-dependent type IIA topological transformations on double-stranded DNA.
- GO:0003918 GO:0003918 defines ATP-driven DNA topoisomerase type II activity.
- PMID:8227000 Peng and Marians 1993 purified and characterized E. coli topoisomerase IV and its subunits.

Mechanism graphs

DNA topoisomerase IV changes DNA topology (FUNCTION)

DNA topoisomerase IV uses ParC and ParE subunits to carry out ATP-dependent type II DNA topoisomerase activity.

Subject	Predicate	Object	Evidence
DNA topoisomerase IV complex	enables	DNA topoisomerase type II activity	`GO:0009340` GO:0009340 defines the DNA topoisomerase IV complex as a type-II topoisomerase that can relax supercoiled DNA and functions in chromosome segregation. `GO:0003918` GO:0003918 is the molecular-function term for ATP-hydrolyzing DNA topoisomerase type II activity.
DNA topoisomerase IV subunit A	contributes to	DNA topoisomerase type II activity	`GO:0009340` GO:0009340 defines topoisomerase IV as containing ParC and ParE. `UniProtKB:P0AFI2` UniProtKB P0AFI2 is the reviewed E. coli K-12 ParC entry.
DNA topoisomerase IV subunit B	contributes to	DNA topoisomerase type II activity	`GO:0009340` GO:0009340 defines topoisomerase IV as containing ParC and ParE. `UniProtKB:P20083` UniProtKB P20083 is the reviewed E. coli K-12 ParE entry.
DNA topoisomerase type II activity	changes topology of	DNA segment	`GO:0003918` GO:0003918 defines a DNA topological transformation driven by ATP hydrolysis and transient cleavage of both strands of one DNA duplex.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral ParC and ParE family groundings before replacing the reviewed-label-only component rows. GO:0009340 exactly grounds the complete DNA topoisomerase IV complex; the verified InterPro ParC and ParE families IPR005742 and IPR005737 are restricted to Gram-negative proteins, while the other candidate families on the E. coli K-12 examples also cover DNA gyrase or multiple type-II-topoisomerase subunit classes.

Evidence

GO:0009340 Gene Ontology cellular-component term for DNA topoisomerase IV complex.
GO:0009330 Gene Ontology cellular-component term for ATP-hydrolyzing DNA topoisomerase type II complexes, the broader class that includes DNA topoisomerase IV.
GO:0032991 Gene Ontology cellular-component term for protein-containing complexes.
GO:0003918 Gene Ontology molecular-function term for ATP-hydrolyzing DNA topoisomerase type II activity.
UniProtKB:P0AFI2 UniProtKB reviewed Escherichia coli K-12 ParC entry.
UniProtKB:P20083 UniProtKB reviewed Escherichia coli K-12 ParE entry.
InterPro:IPR005742 InterPro family for Gram-negative DNA topoisomerase IV subunit A proteins.
InterPro:IPR005737 InterPro family for Gram-negative DNA topoisomerase IV subunit B proteins.
InterPro:IPR050220 InterPro type-II DNA topoisomerase family observed on the E. coli ParC example; broader than the ParC component.
InterPro:IPR001241 InterPro type-IIA DNA topoisomerase family observed on the E. coli ParE example; broader than the ParE component.
PMID:8227000 Peng and Marians 1993, Escherichia coli topoisomerase IV. Purification, characterization, subunit structure, and subunit interactions.
PMID:7783632 PubMed identifier for Luttinger 1995, a review cited by the GO:0009340 term definition.

Curation history

2026-09-24T10:33:14Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-24T10:34:02Z codex · EXPANDED_RECORD — Added topoisomerase-II parentage, ParC/ParE reviewed-label-only components with E. coli K-12 UniProt examples, an E. coli canonical example, type-II DNA topoisomerase function evidence, InterPro boundary discussion, and a compact function graph.
2026-09-24T10:45:16Z codex · ADDRESS_REVIEW — #1479: removed the unsupported Topo IV exact synonym while leaving the GO-backed topoisomerase IV synonym in place.

Source: data/structures/other/dna_topoisomerase_iv_complex.yaml