{"doi":"10.1126/science.adx6053","title":"Deazaguanylation is a nucleobase-protein conjugation required for type IV CBASS immunity","abstract":"7-Deazapurines are nucleobase analogs essential for nucleic acid modifications in nearly all cellular life. In this study, we discovered a role for 7-deazapurines in protein modification within type IV cyclic oligonucleotide-based antiviral signaling system (CBASS) antiphage defense and defined functions for CBASS ancillary proteins Cap9 and Cap10 in nucleobase-protein conjugation. A structure of Cap10 revealed a transfer RNA transglycosylase family enzyme remodeled to bind a partner cGAS/DncV-like nucleotidyltransferase that is modified with an N-terminal 7-amido-7-deazaguanine (NDG) nucleobase. A structure of Cap9 explained how this QueC-like enzyme co-opts a 7-deazapurine biosynthetic reaction to install NDG. We show that Cap9, Cap10, and protein deazaguanylation are essential for host defense against phage infection. Our results define a 7-deazapurine protein modification and explain how nucleobase biosynthetic machinery has been repurposed for antiviral immunity.","journal":"Science","year":2025,"id":531727,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":4,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9669,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":884339,"name":"Patrick Pfaff","orcid":"0000-0002-9761-2497","position":1,"is_corresponding":false},{"id":136624,"name":"Joao A. Paulo","orcid":"0000-0002-4291-413X","position":2,"is_corresponding":false},{"id":107041,"name":"Steven P. Gygi","orcid":"0000-0001-7626-0034","position":3,"is_corresponding":false},{"id":1361,"name":"Kevan M. Shokat","orcid":"0000-0001-8590-7741","position":4,"is_corresponding":false},{"id":230272,"name":"Philip J. Kranzusch","orcid":"0000-0002-4943-733X","position":5,"is_corresponding":false},{"id":872980,"name":"Douglas R. Wassarman","orcid":"0000-0002-6922-9378","position":0,"is_corresponding":true}],"reference_count":51,"raw_metadata":null,"created_at":"2026-07-19T02:51:18.928280Z","pmid":"40997174","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}