{"metadata":{"accession":"PF24729","entry_id":null,"type":"domain","go_terms":null,"source_database":"pfam","member_databases":null,"integrated":"IPR056098","hierarchy":null,"name":{"name":"Acb2/Tad1, hairpin domain","short":"Acb2_Tad1_hairpin"},"description":[{"text":"<p>This domain, previously known as DUF7681, is found in phage proteins including Anti-CBASS protein 2 (Acb2) and Thoeris anti-defense 1 (Tad1). It folds into an alpha-helical hairpin that is found either standalone (in Acb2) or in combination with a four-stranded antiparallel beta-sheet domain (in Tad1) [[cite:PUB00153173],[cite:PUB00156031],[cite:PUB00156032]]. Prokaryotic anti-phage immune systems use TIR and cGAS-like enzymes to produce 1-3-glycocyclic ADP-ribose; and cyclic dinucleotide and trinucleotide signalling molecules, respectively, which limit phage replication. The Thoeris anti-defence proteins Tad1 and Tad2 are both pronged inhibitors and antagonise immunity alongside Anti-CBASS protein 2. These proteins achieve anti-cyclic-oligonucleotide-based anti-phage signalling system (anti-CBASS) activity by sequestering a considerable amount of cyclic nucleotides. Each of these proteins is using distinct binding pockets. The residues conserved in Tad1 and Acb2 are located near these binding sites [[cite:PUB00156032],[cite:PUB00156033]].</p>","llm":false,"checked":false,"updated":false}],"wikipedia":null,"literature":{"PUB00156033":{"PMID":38103556,"ISBN":null,"volume":"84","issue":"2","year":2024,"title":"Phage anti-CBASS protein simultaneously sequesters cyclic trinucleotides and dinucleotides.","URL":null,"raw_pages":"375-385.e7","medline_journal":"Mol Cell","ISO_journal":"Mol Cell","authors":["Cao X","Xiao Y","Huiting E","Cao X","Li D","Ren J","Fedorova I","Wang H","Guan L","Wang Y","Li L","Bondy-Denomy J","Feng Y."],"DOI_URL":"https://doi.org/10.1016/j.molcel.2023.11.026"},"PUB00156031":{"PMID":36174646,"ISBN":null,"volume":"611","issue":"7935","year":2022,"title":"Viruses inhibit TIR gcADPR signalling to overcome bacterial defence.","URL":null,"raw_pages":"326-331","medline_journal":"Nature","ISO_journal":"Nature","authors":["Leavitt A","Yirmiya E","Amitai G","Lu A","Garb J","Herbst E","Morehouse BR","Hobbs SJ","Antine SP","Sun ZJ","Kranzusch PJ","Sorek R."],"DOI_URL":"https://doi.org/10.1038/s41586-022-05375-9"},"PUB00156032":{"PMID":39478223,"ISBN":null,"volume":null,"issue":null,"year":2024,"title":"Single phage proteins sequester signals from TIR and cGAS-like enzymes.","URL":null,"raw_pages":null,"medline_journal":"Nature","ISO_journal":"Nature","authors":["Li D","Xiao Y","Fedorova I","Xiong W","Wang Y","Liu X","Huiting E","Ren J","Gao Z","Zhao X","Cao X","Zhang Y","Bondy-Denomy J","Feng Y."],"DOI_URL":"https://doi.org/10.1038/s41586-024-08122-4"},"PUB00153173":{"PMID":36848932,"ISBN":null,"volume":"616","issue":"7956","year":2023,"title":"Ubiquitin-like conjugation by bacterial cGAS enhances anti-phage defence.","URL":null,"raw_pages":"326-331","medline_journal":"Nature","ISO_journal":"Nature","authors":["Jenson JM","Li T","Du F","Ea CK","Chen ZJ."],"DOI_URL":"https://doi.org/10.1038/s41586-023-05862-7"}},"set_info":null,"overlaps_with":null,"counters":{"subfamilies":0,"domain_architectures":7,"interactions":0,"matches":832,"pathways":0,"proteins":831,"proteomes":784,"sets":0,"structural_models":{"alphafold":333},"structures":20,"taxa":1869},"entry_annotations":{"hmm":0,"logo":0,"alignment:seed":156,"alignment:full":436},"cross_references":{},"is_llm":false,"is_reviewed_llm":false,"is_updated_llm":false,"representative_structure":{"accession":"7uq2","name":"Vs.4 from T4 phage in complex with cGAMP"}}}