id: Pfam:PF18967
pfam_id: PF18967
name: Pycsar effector protein domain
short_name: PycTM
seed_status: EX_DUF
characterization_status: UNSCORED
curation_status: SEEDED
source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/PF18967
counters:
  proteins: 4373
  matches: 4373
  proteomes: 3328
  taxa: 4875
  structures: 0
  alphafold_models: 2626
  domain_architectures: 11
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:IPR043760
description: Pycsar (pyrimidine cyclase system for antiphage resistance) provides immunity against bacteriophage
  and consists of a pyrimidine cyclase (PycC), which synthesizes cyclic nucleotides in response to infection,
  and an effector protein. Cyclic nucleotides serve as specific second messenger signals, which activate
  the adjacent effector, leading to bacterial cell death and abortive phage infection [[cite:PUB00100705]].
  This entry represents a domain found in the effector protein from Pycsar system. Structure prediction
  suggests it may form a homohexameric complex. This domain is found either standalone or in combination
  with HD domain [pfam:PF01966].