id: Pfam:PF17262
pfam_id: PF17262
name: Cas6b C-terminal domain
short_name: Cas6b_C
seed_status: EX_DUF
characterization_status: UNSCORED
curation_status: SEEDED
source_url: https://www.ebi.ac.uk/interpro/api/entry/pfam/PF17262
counters:
  proteins: 251
  matches: 251
  proteomes: 213
  taxa: 538
  structures: 2
  alphafold_models: 202
  domain_architectures: 2
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:IPR020209
description: Clustered, regularly interspaced, short palindromic repeat (CRISPR) loci play a pivotal role
  in the prokaryotic host defense system against invading genetic materials. The CRISPR loci are transcribed
  to produce CRISPR RNAs (crRNAs), which form interference complexes with CRISPR-associated (Cas) proteins
  to target the invading nucleic acid for degradation [[cite:PUB00085375]]. Four Cas proteins (Cas5, Cas6b,
  Cas7 and Cas8b) are proposed to form a Type I-B Cascade complex that mediates the antiviral defense
  [[cite:PUB00085160]]. This is the C-terminal domain found in Cas6b proteins. Cas6b is a member of Cas6
  RNA processing endoribonucleases found in bacteria and archaea whose RNA substrates have a wide range
  of structural features. Cocrystal structures of Cas6 from Methanococcus maripaludis (MmCas6b) bound
  with its repeat RNA revealed a dual-site binding structure and a cleavage site conformation poised for
  phosphodiester bond breakage [[cite:PUB00085376]].