AcrEF-TolC multidrug efflux transport complex

cellstructuremech:acref_tolc_multidrug_efflux_transport_complex · Other · Multiprotein complex · Proposed

An Escherichia coli Resistance-Nodulation-Division-family cell-envelope efflux pump complex composed of AcrE, AcrF, and TolC subunits that exports acriflavines, indoles, and other xenobiotic substrates across the cell envelope. [ComplexPortal:CPX-4265]

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
Multidrug export protein AcrE	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	acrE		ESSENTIAL	Periplasmic membrane-fusion adaptor subunit that links AcrF to the TolC outer-membrane channel in the AcrEF-TolC conduit. `ComplexPortal:CPX-4265` Complex Portal CPX-4265 curates P24180/AcrE as an E. coli K-12 AcrEF-TolC multidrug efflux transport complex participant. `UniProtKB:P24180` UniProtKB P24180 is the reviewed E. coli K-12 entry for Multidrug export protein AcrE.
Multidrug export protein AcrF	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	acrF		ESSENTIAL	Inner-membrane RND transporter subunit that forms the AcrEF transport core for xenobiotic export through the AcrE/TolC conduit. `ComplexPortal:CPX-4265` Complex Portal CPX-4265 curates P24181/AcrF as an E. coli K-12 AcrEF-TolC multidrug efflux transport complex participant. `UniProtKB:P24181` UniProtKB P24181 is the reviewed E. coli K-12 entry for Multidrug export protein AcrF.
Outer membrane channel protein TolC	Protein	part of	`InterPro:IPR058622`	tolC	3 copies in the E. coli K-12 Complex Portal CPX-4265 entry	ESSENTIAL	Trimeric outer-membrane channel constituent that completes the AcrEF-TolC cell-envelope efflux conduit. `ComplexPortal:CPX-4265` Complex Portal CPX-4265 curates P02930/TolC as three copies in the E. coli K-12 AcrEF-TolC multidrug efflux transport complex. `UniProtKB:P02930` UniProtKB P02930 is the reviewed E. coli K-12 entry for Outer membrane protein TolC. `InterPro:IPR058622` InterPro IPR058622 is the Outer membrane channel protein TolC family entry.

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.

Multidrug export protein AcrE

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P24180`	Multidrug export protein AcrE	acrE	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (1 reference) `UniProtKB:P24180` Reviewed Swiss-Prot entry ACRE_ECOLI is the E. coli K-12 AcrE accession and cross-references ComplexPortal:CPX-4265.

Multidrug export protein AcrF

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P24181`	Multidrug export protein AcrF	acrF	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (1 reference) `UniProtKB:P24181` Reviewed Swiss-Prot entry ACRF_ECOLI is the E. coli K-12 AcrF accession and cross-references ComplexPortal:CPX-4265.

Outer membrane channel protein TolC

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P02930`	Outer membrane protein TolC	tolC	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (1 reference) `UniProtKB:P02930` Reviewed Swiss-Prot entry TOLC_ECOLI is the E. coli K-12 TolC accession and cross-references ComplexPortal:CPX-4265.

Source composition assertions

AcrEF-TolC multidrug efflux transport complex (ComplexPortal:CPX-4265)

Escherichia coli (strain K12) (NCBITaxon:83333) · ECO:0005547 · retrieved 2026-10-02

Participant	Source type	Source name	Stoichiometry
`UniProtKB:P24180` — Multidrug export protein AcrE	protein	acrE	not asserted
`UniProtKB:P24181` — Multidrug export protein AcrF	protein	acrF	not asserted
`UniProtKB:P02930` — Outer membrane protein TolC	protein	tolC	3

Curator-scoped import: E. coli K-12 AcrEF-TolC source composition for this record. Source evidence: inferred by curator. The accession was resolved through the Complex Portal accession endpoint; no equivalence xref was inferred.

Canonical examples

NCBITaxon:83333 Escherichia coli K-12 — Source strain for Complex Portal CPX-4265, which curates AcrE, AcrF, and TolC as the participants of AcrEF-TolC. [ComplexPortal:CPX-4265]

Functions

xenobiotic transmembrane transporter activity GO:0042910 — The AcrEF-TolC complex exports acriflavine, indole, and other xenobiotic substrates across the E. coli cell envelope through the coupled AcrF transporter, AcrE adaptor, and TolC channel.
- GO:0042910 GO:0042910 is the molecular-function term for xenobiotic transmembrane transporter activity.
- ComplexPortal:CPX-4265 Complex Portal cross-references GO:0042910 for the E. coli K-12 AcrEF-TolC multidrug efflux transport complex.

Mechanism graphs

AcrEF-TolC exports xenobiotics across the cell envelope (FUNCTION)

AcrF, AcrE, and TolC form an envelope-spanning RND efflux pump that exports acriflavine, indole, and other xenobiotic substrates from E. coli.

Subject	Predicate	Object	Evidence
Multidrug export protein AcrF	couples to	Multidrug export protein AcrE	`ComplexPortal:CPX-4265` CPX-4265 curates AcrE and AcrF as participants in the E. coli AcrEF-TolC pump.
Multidrug export protein AcrE	couples to	Outer membrane channel protein TolC	`ComplexPortal:CPX-4265` CPX-4265 curates AcrE and TolC as participants in the E. coli AcrEF-TolC pump.
AcrEF-TolC multidrug efflux transport complex	enables	xenobiotic transmembrane transporter activity	`ComplexPortal:CPX-4265` Complex Portal cross-references GO:0042910 for the AcrEF-TolC complex.
xenobiotic transmembrane transporter activity	transports	xenobiotic substrate	`ComplexPortal:CPX-4265` CPX-4265 summarizes the AcrEF-TolC complex as transporting acriflavines and indoles.
xenobiotic detoxification by transmembrane export across the cell outer membrane	targets	cell exterior	`GO:0140330` GO:0140330 describes reducing xenobiotic toxicity by export through the outer membrane.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral protein families for AcrE and AcrF before replacing their reviewed-label-only component rows. ComplexPortal:CPX-4265 and the reviewed E. coli K-12 UniProt records exactly identify AcrE and AcrF, but no InterPro, Pfam, NCBIfam, or GO accession was verified as an exact source-neutral family for either named pump constituent; TolC is grounded to InterPro:IPR058622.

Evidence

ComplexPortal:CPX-4265 Complex Portal entry for the E. coli K-12 AcrEF-TolC multidrug efflux transport complex.
GO:1990281 Gene Ontology cellular-component parent term for efflux pump complexes.
GO:0042910 Gene Ontology molecular-function term for xenobiotic transmembrane transporter activity.
GO:0140330 Gene Ontology biological-process term for xenobiotic detoxification by transmembrane export across the cell outer membrane.
InterPro:IPR058622 InterPro family entry for Outer membrane channel protein TolC.
UniProtKB:P24180 Reviewed E. coli K-12 AcrE UniProtKB entry.
UniProtKB:P24181 Reviewed E. coli K-12 AcrF UniProtKB entry.
UniProtKB:P02930 Reviewed E. coli K-12 TolC UniProtKB entry.
PMID:30880703 PubMed identifier for Srinivasan et al. 2018, Transcriptional response of AcrEF-TolC against fluoroquinolone and carbapenem in Escherichia coli of clinical origin.
DOI:10.4103/ijmm.IJMM_18_308 DOI for Srinivasan et al. 2018, Transcriptional response of AcrEF-TolC against fluoroquinolone and carbapenem in Escherichia coli of clinical origin.
PMID:26113845 PubMed identifier for Zwama and Pos 2015, The ins and outs of RND efflux pumps in Escherichia coli.
DOI:10.3389/fmicb.2015.00587 DOI for Zwama and Pos 2015, The ins and outs of RND efflux pumps in Escherichia coli.

Curation history

2026-10-02T10:46:19Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-02T10:47:17Z codex · EXPANDED_RECORD — Added CPX-4265/GO efflux-pump parentage, AcrE, AcrF, and TolC component rows with E. coli K-12 reviewed UniProt examples, exact InterPro grounding for TolC, a compact xenobiotic export graph, the Complex Portal CPX-4265 source composition, and an AcrE/AcrF component-family grounding TODO.

Source: data/structures/other/acref_tolc_multidrug_efflux_transport_complex.yaml