TAM protein secretion complex

GO:0097347 · Secretion system · Multiprotein complex · Proposed

A heterooligomeric protein complex that spans the bacterial periplasm and enables the secretion of adhesin proteins in Gram-negative bacteria. In Citrobacter rodentium, Salmonella enterica and Escherichia coli, the TAM complex consists of an Omp85-family protein, TamA, in the outer membrane and TamB in the inner membrane. [GO:0097347]

Synonyms: translocation and assembly module protein 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
TamA Omp85-family outer-membrane protein	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	tamA			Outer-membrane Omp85-family constituent of the translocation and assembly module. `GO:0097347` GO:0097347 defines bacterial TAM as consisting of an Omp85-family TamA protein in the outer membrane and TamB in the inner membrane in the named Gram-negative example species. `PMID:22466966` The PubMed/Europe PMC abstract for Selkrig et al. 2012 reports TamA as TAM's Omp85-family outer-membrane protein partner.
TamB inner-membrane protein	Protein	part of	Reviewed label only (reviewed name; no accession asserted)	tamB			Inner-membrane constituent of the translocation and assembly module that pairs with TamA across the bacterial periplasm. `GO:0097347` GO:0097347 defines bacterial TAM as consisting of an Omp85-family TamA protein in the outer membrane and TamB in the inner membrane in the named Gram-negative example species. `PMID:22466966` The PubMed/Europe PMC abstract for Selkrig et al. 2012 reports TamB as TAM's inner-membrane protein partner.

Taxonomic distribution

NCBITaxon:2 Bacteria — VARIABLE: GO:0097347 scopes TAM to Gram-negative bacteria, so the periplasm-spanning TamA/TamB complex is represented as a variable bacterial secretion complex rather than a universal bacterial structure. [GO:0097347]

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral TamA and TamB family grounding before replacing the reviewed-label-only TAM constituents. GO:0097347 and the TAM discovery paper support TamA and TamB as constituents, but TamA belongs to the broad Omp85 family and the first pass did not verify exact InterPro, Pfam, or NCBIfam accessions specific to the TAM partners.
CURATION_TODO (OPEN): Curate a TAM function row only after deciding whether the record should use a narrow autotransporter biogenesis wording or a broader adhesin-protein secretion wording. GO:0097347 labels TAM as a protein secretion complex, while the definition paper discovered it through efficient secretion of autotransporter adhesins; the first record therefore avoids overclaiming a generic type V secretion function.

Evidence

GO:0097347 Gene Ontology cellular-component term for the TAM protein secretion complex.
PMID:22466966 The PubMed/Europe PMC abstract for Selkrig et al. 2012 reports the translocation and assembly module and its TamA/TamB composition in Citrobacter rodentium, Salmonella enterica, and Escherichia coli.
DOI:10.1038/nsmb.2261 NCBI and Europe PMC metadata verify DOI 10.1038/nsmb.2261 as the DOI for the Selkrig et al. 2012 discovery paper cited by the GO:0097347 definition PMID.

Curation history

2026-09-29T04:50:32Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-29T04:51:17Z codex · EXPANDED_RECORD — Added GO synonymy, protein-containing-complex parentage, reviewed-label-only TamA/TamB constituents, bacterial taxonomic scope, GO/PubMed/DOI evidence, and open TAM component and function boundary discussions.
2026-09-29T05:05:24Z codex · EXPANDED_RECORD — Bound Selkrig et al. 2012 evidence notes to the public PubMed/Europe PMC abstract and DOI metadata checked during the PR review.

Source: data/structures/secretion_system/tam_protein_secretion_complex.yaml