id: Pfam:PF22479
pfam_id: PF22479
name: Cyanophage baseplate Pam3 plug gp18
short_name: Pam3_gp18
seed_status: EX_DUF
characterization_status: UNSCORED
curation_status: SEEDED
source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/PF22479
counters:
  proteins: 1235
  matches: 1235
  proteomes: 1081
  taxa: 2192
  structures: 9
  alphafold_models: 507
  domain_architectures: 6
provenance:
  snapshot_id: interpro-pfam-duf-2026-10-10
  path: data/worklists/interpro-pfam-duf-2026-10-10.json
  sha256: 17fb625876c9326ed284263a47bcd84e0d7844a31c040dc06cd2260c36f1c383
  generated_at: '2026-10-10T07:44:21.614711Z'
  source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/
interpro_id: InterPro:IPR054252
description: 'This family, previously known as DUF6983, represents Cyanophage baseplate Pam3 plug gp18
  and related proteins. Gp18 has structural similarity to a component of the baseplate Complex for Myoviridae
  Phage XM1. The cyanophage Pam3 has a substantially simpler molecular organisation than the prototypical,
  contractile-tail bacteriophage T4, but it retains the essential elements required for DNA injection.
  The baseplate of Pam3 contains six protein components: the trimeric spike gp20, the trimeric hub gp19,
  the baseplate wedge (six heterotriplexes of gp22-gp23), the plug of six gp18 monomers, and the fibers
  (12 trimers of gp24) [[cite:PUB00154413]]. The plug gp18 consists of two-layered beta-sheets and a C-terminal
  alpha-helix, resembling the immunoglobin fold. Each plug monomer is embedded between the two C-terminal
  helices of the tube initiator, forming a ''plug'' to fix the core helical bundle of the wedge onto the
  hub [[cite:PUB00154413]]'