ammonium transmembrane transporter complex

GO:0110067 · Other · Multiprotein complex · Proposed

High affinity ammonium transporter complex that enables the transfer of ammonium from one side of a membrane to the other. [GO:0110067]

Synonyms: AMT1 complex

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
Ammonium transporter	Protein	part of	`InterPro:IPR001905`	amtB	3 copies per E. coli AmtB homotrimer in PDB:1U7G biological assembly 1	UNKNOWN	Amt-family membrane channel subunit that assembles as a homotrimer for high-affinity ammonium uptake. `GO:0110067` GO:0110067 defines the ammonium transmembrane transporter complex. `InterPro:IPR001905` InterPro IPR001905 is the Ammonium transporter family entry and excludes the Rhesus subgroup. `PDB:1U7G` RCSB describes PDB:1U7G biological assembly 1 as a homotrimeric E. coli AmtB ammonia-channel structure.

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.

Ammonium transporter

Accession	Protein	Gene	Organism	Entry
`UniProtKB:P69681`	Ammonium transporter AmtB	amtB	Escherichia coli K-12 (`NCBITaxon:83333`)	REVIEWED
Role and evidence (2 references) Reviewed E. coli K-12 AmtB accession mapped by RCSB to the polymer entity in PDB:1U7G. `UniProtKB:P69681` UniProtKB P69681 is the reviewed Escherichia coli K-12 entry for AmtB. `PDB:1U7G` RCSB SIFTS maps PDB:1U7G polymer entity 1 to UniProtKB:P69681.

Canonical examples

NCBITaxon:562 Escherichia coli — E. coli source of the trimeric AmtB ammonia channel structure deposited as PDB:1U7G. [PDB:1U7G]

Functions

ammonium channel activity GO:0008519 — AmtB trimers mediate energy-independent facilitated ammonium diffusion through a transmembrane channel.
- GO:0110067 GO:0110067 has a capable-of relation to GO:0008519 ammonium channel activity.
- GO:0008519 GO:0008519 is the molecular-function term for ammonium channel activity.

Physical properties

SUBUNIT_COUNT: 3 (E. coli AmtB homotrimer in PDB:1U7G biological assembly 1) [PDB:1U7G]

Evidence

GO:0110067 Gene Ontology cellular-component term for the ammonium transmembrane transporter complex.
GO:1902495 QuickGO reports GO:0110067 as an is-a child of GO:1902495 transmembrane transporter complex.
GO:0008519 Gene Ontology molecular-function term for ammonium channel activity.
GO:0072488 Gene Ontology biological-process term for ammonium transmembrane transport.
InterPro:IPR001905 InterPro family entry for Amt-family ammonium transporters.
UniProtKB:P69681 UniProtKB reviewed E. coli K-12 AmtB entry.
PDB:1U7G RCSB Protein Data Bank entry for the trimeric E. coli AmtB ammonia-channel structure at 1.35 A.
PMID:15361618 PubMed identifier for Khademi et al. 2004, the Science E. coli AmtB structural paper cited by PDB:1U7G.
DOI:10.1126/science.1101952 DOI for Khademi et al. 2004, 'Mechanism of ammonia transport by Amt/MEP/Rh: structure of AmtB at 1.35 A', as reported by PubMed.

Curation history

2026-10-01T18:46:47Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-10-01T18:47:59Z codex · EXPANDED_RECORD — Added GO narrow synonymy and transmembrane-transporter parentage, grounded the Amt-family constituent to exact InterPro family IPR001905, added the E. coli PDB:1U7G homotrimer with a reviewed UniProt example, and cited GO/InterPro/UniProt/PDB/PMID/DOI evidence.

Source: data/structures/other/ammonium_transmembrane_transporter_complex.yaml