3-phenylpropionate dioxygenase complex

GO:0009334 · Other · Multiprotein complex · Proposed

Enzyme complex consisting of four proteins: the two subunits of the hydroxylase component (hcaE and hcaF), a ferredoxin (hcaC) and a ferredoxin reductase (hcaD). Converts 3-phenylpropionic acid (PP) into cis-3-(3-carboxyethyl)-3,5-cyclohexadiene-1,2-diol (PP-dihydrodiol). [GO:0009334]

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

Components

Component	Type	Part of / acts on	Grounding	Genes	Essential	Role
3-phenylpropionate/cinnamic acid dioxygenase, alpha subunit	Protein	part of	`InterPro:IPR020875`	hcaE	UNKNOWN	Hydroxylase alpha subunit of the Hca 3-phenylpropionate dioxygenase. `GO:0009334` GO:0009334 defines hcaE as one of the four proteins in the 3-phenylpropionate dioxygenase complex. `InterPro:IPR020875` InterPro IPR020875 is the 3-phenylpropionate/cinnamic acid dioxygenase, alpha subunit family entry. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster that encodes the initial 3-phenylpropionic acid dioxygenase pathway.
3-phenylpropionate/cinnamic acid dioxygenase, beta subunit	Protein	part of	`InterPro:IPR023712`	hcaF	UNKNOWN	Hydroxylase beta subunit of the Hca 3-phenylpropionate dioxygenase. `GO:0009334` GO:0009334 defines hcaF as one of the four proteins in the 3-phenylpropionate dioxygenase complex. `InterPro:IPR023712` InterPro IPR023712 is the 3-phenylpropionate/cinnamic acid dioxygenase, beta subunit family entry. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster that encodes the initial 3-phenylpropionic acid dioxygenase pathway.
3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin subunit	Protein	part of	`InterPro:IPR023739`	hcaC	UNKNOWN	Ferredoxin subunit that transfers electrons in the Hca 3-phenylpropionate dioxygenase. `GO:0009334` GO:0009334 defines hcaC as one of the four proteins in the 3-phenylpropionate dioxygenase complex. `InterPro:IPR023739` InterPro IPR023739 is the 3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin subunit family entry. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster that encodes the initial 3-phenylpropionic acid dioxygenase pathway.
3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin--NAD(+) reductase subunit	Protein	part of	`InterPro:IPR023744`	hcaD	UNKNOWN	Ferredoxin--NAD(+) reductase subunit of the Hca 3-phenylpropionate dioxygenase. `GO:0009334` GO:0009334 defines hcaD as one of the four proteins in the 3-phenylpropionate dioxygenase complex. `InterPro:IPR023744` InterPro IPR023744 is the 3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin--NAD(+) reductase subunit family entry. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster that encodes the initial 3-phenylpropionic acid dioxygenase pathway.

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.

3-phenylpropionate/cinnamic acid dioxygenase, alpha subunit

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P0ABR5`	3-phenylpropionate/cinnamic acid dioxygenase subunit alpha	hcaE	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 hcaE accession for the GO:0009334 3-phenylpropionate dioxygenase complex. `UniProtKB:P0ABR5` UniProtKB P0ABR5 is the reviewed Escherichia coli K-12 entry for hcaE. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster encoding 3-phenylpropionic acid dioxygenolytic catabolism.

3-phenylpropionate/cinnamic acid dioxygenase, beta subunit

Accession	Protein	Gene	Organism	Entry
`UniProtKB:Q47140`	3-phenylpropionate/cinnamic acid dioxygenase subunit beta	hcaF	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 hcaF accession for the GO:0009334 3-phenylpropionate dioxygenase complex. `UniProtKB:Q47140` UniProtKB Q47140 is the reviewed Escherichia coli K-12 entry for hcaF. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster encoding 3-phenylpropionic acid dioxygenolytic catabolism.

3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin subunit

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P0ABW0`	3-phenylpropionate/cinnamic acid dioxygenase ferredoxin subunit	hcaC	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 hcaC accession for the GO:0009334 3-phenylpropionate dioxygenase complex. `UniProtKB:P0ABW0` UniProtKB P0ABW0 is the reviewed Escherichia coli K-12 entry for hcaC. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster encoding 3-phenylpropionic acid dioxygenolytic catabolism.

3-phenylpropionate/cinnamic acid dioxygenase, ferredoxin--NAD(+) reductase subunit

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P77650`	3-phenylpropionate/cinnamic acid dioxygenase ferredoxin--NAD(+) reductase component	hcaD	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 hcaD accession for the GO:0009334 3-phenylpropionate dioxygenase complex. `UniProtKB:P77650` UniProtKB P77650 is the reviewed Escherichia coli K-12 entry for hcaD. `PMID:9603882` Díaz et al. 1998 characterized the E. coli K-12 hca cluster encoding 3-phenylpropionic acid dioxygenolytic catabolism.

Canonical examples

NCBITaxon:83333 Escherichia coli K-12 — E. coli K-12 source of the hca-encoded 3-phenylpropionate dioxygenase complex curated by GO:0009334. [PMID:9603882]

Functions

3-phenylpropionate dioxygenase activity GO:0008695 — The Hca complex converts 3-phenylpropionate, NADH, oxygen, and a proton to PP-dihydrodiol and NAD+.
- GO:0009334 GO:0009334 is capable of GO:0008695 3-phenylpropionate dioxygenase activity.
- GO:0008695 GO:0008695 is the molecular-function term for 3-phenylpropionate dioxygenase activity.

Evidence

GO:0009334 Gene Ontology cellular-component term for the 3-phenylpropionate dioxygenase complex.
GO:1990204 QuickGO reports GO:0009334 as an is-a child of GO:1990204 oxidoreductase complex.
GO:0008695 Gene Ontology molecular-function term for 3-phenylpropionate dioxygenase activity.
InterPro:IPR020875 InterPro family entry for HcaE alpha subunits.
InterPro:IPR023712 InterPro family entry for HcaF beta subunits.
InterPro:IPR023739 InterPro family entry for HcaC ferredoxin subunits.
InterPro:IPR023744 InterPro family entry for HcaD ferredoxin--NAD(+) reductase subunits.
UniProtKB:P0ABR5 UniProtKB reviewed E. coli K-12 HcaE entry.
UniProtKB:Q47140 UniProtKB reviewed E. coli K-12 HcaF entry.
UniProtKB:P0ABW0 UniProtKB reviewed E. coli K-12 HcaC entry.
UniProtKB:P77650 UniProtKB reviewed E. coli K-12 HcaD entry.
PMID:9603882 PubMed identifier for Díaz, Ferrández and García 1998, the Journal of Bacteriology hca cluster characterization paper cited by GO:0009334.
DOI:10.1128/JB.180.11.2915-2923.1998 DOI for Díaz, Ferrández and García 1998, as reported by PubMed.

Curation history

2026-10-02T00:49:27Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-02T00:50:23Z codex · EXPANDED_RECORD — Added oxidoreductase-complex parentage, four exact InterPro-grounded Hca constituents with reviewed E. coli K-12 UniProt examples, an E. coli K-12 canonical example, 3-phenylpropionate dioxygenase activity, and GO/PubMed/DOI evidence.

Source: data/structures/other/3_phenylpropionate_dioxygenase_complex.yaml