{"doi":"10.1016/j.chom.2021.09.002","title":"Prophages encode phage-defense systems with cognate self-immunity","abstract":"Temperate phages are pervasive in bacterial genomes, existing as vertically inherited islands termed prophages. Prophages are vulnerable to predation of their host bacterium by exogenous phages. Here, we identify BstA, a family of prophage-encoded phage-defense proteins in diverse Gram-negative bacteria. BstA localizes to sites of exogenous phage DNA replication and mediates abortive infection, suppressing the competing phage epidemic. During lytic replication, the BstA-encoding prophage is not itself inhibited by BstA due to self-immunity conferred by the anti-BstA (aba) element, a short stretch of DNA within the bstA locus. Inhibition of phage replication by distinct BstA proteins from Salmonella, Klebsiella, and Escherichia prophages is generally interchangeable, but each possesses a cognate aba element. The specificity of the aba element ensures that immunity is exclusive to the replicating prophage, preventing exploitation by variant BstA-encoding phages. The BstA protein allows prophages to defend host cells against exogenous phage attack without sacrificing the ability to replicate lytically.","journal":"Cell Host & Microbe","year":2021,"id":148074,"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":137,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9533,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":555890,"name":"Nicolas Wenner","orcid":"0000-0001-6257-9423","position":1,"is_corresponding":false},{"id":555891,"name":"Charles L. Dulberger","orcid":"0000-0002-1334-5468","position":2,"is_corresponding":false},{"id":555892,"name":"Ella V. Rodwell","orcid":"0000-0002-6358-6542","position":3,"is_corresponding":false},{"id":556661,"name":"Arthur Bowers-Barnard","orcid":null,"position":4,"is_corresponding":false},{"id":89646,"name":"Natalia Quinones-Olvera","orcid":"0000-0002-4612-6819","position":5,"is_corresponding":false},{"id":555893,"name":"Daniel J. Rigden","orcid":"0000-0002-7565-8937","position":6,"is_corresponding":false},{"id":247777,"name":"Eric J. Rubin","orcid":"0000-0001-5120-962X","position":7,"is_corresponding":false},{"id":295159,"name":"Ethan C. Garner","orcid":"0000-0003-0141-3555","position":8,"is_corresponding":false},{"id":276820,"name":"Michael Baym","orcid":"0000-0003-1303-5598","position":9,"is_corresponding":false},{"id":555894,"name":"Jay C. D. Hinton","orcid":"0000-0003-2671-6026","position":10,"is_corresponding":false},{"id":555889,"name":"Siân V. Owen","orcid":"0000-0001-5330-3177","position":0,"is_corresponding":true}],"reference_count":89,"raw_metadata":null,"created_at":"2026-07-18T23:42:41.063423Z","pmid":"34597593","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":[]}